The authors acknowledge The Netherlands Organization for Scientific research (NWO ECHO-STIP Grant 717.013.005, NWO VIDI Grant 723.014.006) for the financial support.

1. Synthesis of Core-shell Silica Particles
Note: Silica particles are synthesized according to the following procedure, which is based on the St&#246;ber method24,25.
<ol>
	<li>Synthesis of fluorescent silica seeds
	<ol>
		<li>Dissolve 105 mg (0.27 mmol) of fluorescein-isothiocyanate in 5 ml of ethanol.</li>
		<li>Add 100 &#181;l of (3-aminopropyl) triethoxysilane (APTES, 0.43 mmol) to the previous solution.</li>
		<li>Sonicate the solution during 5 min and let it react overnight under an argon atmosphere at room temperature while stirring. The dye-functionalized APTES complex is used without purification.</li>
		<li>In a 1 L round-bottom flask mix 2.5 ml of the dye-functionalized APTES with 25 ml of ammonia (25% in water) and 250 ml of ethanol.</li>
		<li>Add 10 ml of tetraethylorthosilicate (TEOS) under the meniscus of the previous reaction mixture with the help of a glass pipette while stirring with a magnetic stirrer.</li>
		<li>Similarly, after 5 hr, add another 1.75 ml of TEOS and stir the mixture overnight under an argon atmosphere.</li>
		<li>Pour the dispersion into several 45 ml tubes.</li>
		<li>Centrifuge the tubes (350 x g, 30 min), remove the supernatant and add 30 ml of fresh ethanol in each tube. Sonicate the new dispersions for 3 min, and centrifuge again to remove the supernatant. Repeat these washing steps 3 times.</li>
		<li>Keep the fluorescent seeds in ethanol in a concentration of about 13.6 mg/ml and in the dark (avoid exposure to light).</li>
		<li>Prepare non-fluorescent seeds following the same procedure omitting the addition of the fluorescent dye. 
		Note: Following this procedure, seeds of about 100 nm in radius are obtained.</li>
	</ol>
	</li>
	<li>Synthesis of core-shell silica particles
	<ol>
		<li>Fill a 1 L round-bottom flask with 51 ml of ethanol, 17 ml of deionized water, 3.4 ml of ammonia (25% in water) and 4 ml of the seed dispersion (54.4 mg of fluorescent seeds approximately).</li>
		<li>Fill a plastic syringe with 5 ml of TEOS and 10 ml of ethanol.</li>
		<li>Fill a second plastic syringe with 1.34 ml of ammonia (25% in water), 3.4 ml of deionized water and 10.25 ml of ethanol.</li>
		<li>Connect both syringes to the round-bottom flask with plastic tubing.</li>
		<li>Equip the flask with an argon flow and a magnetic stirrer. The argon inlet has to be next to the outlet of the second syringe to avoid contact between ammonia gases from the TEOS droplets to prevent secondary nucleation.</li>
		<li>Add the content of both syringes at the same time at 1.7 ml/hr using peristaltic pumps while stirring the mixture. Ensure to obtain free falling droplets to avoid gliding on the walls and therefore secondary nucleation.</li>
		<li>Stop the addition after 7 hr to obtain core-shell particles of approximately 300 nm in radius.</li>
		<li>Pour the content of the flask into several 45 ml tubes.</li>
		<li>Centrifuge the tubes (350 x g, 30 min), remove the supernatant and add 30 ml of fresh ethanol in each tube. Sonicate the new dispersion for 3 min, and centrifuge again to remove the supernatant. Repeat these washing steps 3 times.</li>
		<li>Keep the core-shell particles in ethanol and in the dark (avoid exposure to light).</li>
		<li>Prepare non-fluorescent silica particles following the same procedure but using the non-fluorescent seeds.</li>
	</ol>
	</li>
</ol>
2. Functionalization of Silica Colloids
<ol>
	<li>Synthesis of NVOC-functionalized colloids
	<ol>
		<li>Disperse 10 mg of core-shell silica particles in 1 ml of ethanol together with 12 mg (0.03 mmol) of the NVOC-C11-OH molecule and 31 mg (0.11 mmol) of stearyl alcohol in a 50 ml round-bottom flask (resulting in a 20/80 NVOC-C11-OH/stearyl alcohol molar ratio).</li>
		<li>Sonicate the mixture for 10 min to ensure that all molecules are dissolved and the particles are well dispersed.</li>
		<li>Add to the mixture a magnetic stirrer bar and evaporate the ethanol with a steady stream of argon at room temperature. Before proceeding, ensure that there is no ethanol left, otherwise it could react with the silanol groups of the particles. To check whether the ethanol is completely evaporated pay attention to the temperature of the bottom of the flask. If it feels cold, ethanol is not yet completely evaporated.</li>
		<li>Heat the flask up to 180 &#176;C for 6 hr under continuous stirring and under a steady stream of argon22.</li>
		<li>Let the flask cool down to room temperature.</li>
		<li>Add 3 ml of CHCl3 into the flask and sonicate for 5 min (or until all the solid content has been dissolved or dispersed).</li>
		<li>Centrifuge the dispersion (2,600 x g, 4 min), remove the supernatant and add fresh CHCl3. Sonicate the new dispersion for 3 min, and centrifuge again to remove the supernatant. Repeat these washing steps 6 times.</li>
		<li>Dry the particles at 70 &#176;C in vacuo overnight and store them in a desiccator.</li>
	</ol>
	</li>
	<li>Synthesis of BTA-colloids
	<ol>
		<li>Disperse 10 mg of particles functionalized with a 20/80 molar ratio of NVOC-C11-OH/stearyl alcohol in 3 ml of CHCl3.</li>
		<li>Irradiate the dispersion in a UV-oven (&#955;max=354 nm) for 1 hr to cleave the NVOC group. Ensure that the deprotection is homogeneous on the surface of the particles by stirring the dispersion gently with a magnetic stirrer while deprotecting. This yields the amine-functionalized particles (Figure 1a).</li>
		<li>Dissolve 9 mg of the benzene-1,3,5-tricarboxamide derivative (BTA, 0.01 mmol), 8.7 &#181;l of N,N-diisopropylethylamine (DIPEA, 0.05 mmol) and 5.2 mg of (benzotriazol-1-yloxy)tripyrrolidinophosphonium hexafluorophosphate (PyBOP, 0.01 mmol) in 1 ml of CHCl3.</li>
		<li>Add the solution to the amine- functionalized particle dispersion and stir overnight at room temperature and under an argon atmosphere.</li>
		<li>Centrifuge the dispersion (2,600 x g, 4 min), remove the supernatant and add 3 ml of fresh CHCl3. Sonicate the new dispersion for 3 min, and centrifuge again to remove the supernatant. Repeat these washing steps 6 times.</li>
		<li>Dry the particles at 70 &#176;C in vacuo for 48 hr and store them in a desiccator.</li>
	</ol>
	</li>
</ol>
3. Static Light Scattering Measurements (SLS)
Note: Use non-fluorescent particles, since the fluorescent core absorbs light of the same wavelength as the incident laser light of conventional light scattering equipment.
<ol>
	<li>Functionalize 10 mg of non-fluorescent silica particles with stearyl alcohol only (no NVOC-C11-OH) following the procedure described in section 2.1.</li>
	<li>Prepare 500 &#956;l of a dispersion of 0.033 mg/ml of non-functionalized particles in water and another one of 2 mg/ml of the stearyl alcohol-coated particles in cyclohexane.</li>
	<li>Sonicate both dispersions for at least 20 min to ensure that the particles are well dispersed.</li>
	<li>Measure the scattered intensity of both dispersions, the solvents and the reference solvent from 30&#176; to 120&#176; in steps of 5&#176;.</li>
	<li>Plot the intensity of the sample (Isample) as a function of q 
	(Equation 1) q = 4&#960;nsolventsin(&#952;/2)/&#955;o 
	with the scattering angle &#952;, the refractive index of the solvent nsolvent and the wavelength of the laser &#955;o.</li>
	<li>Fit the data to the following equation using software (e.g., Origin) 
	(Equation 2) Isample = CP(qR) 
	where C is a constant and the form factor P(qR) is given by 
	(Equation 3)<img alt="Equation 3" src="/files/ftp_upload/53934/53934eq3.jpg" /> 
	 
	wherein the average radius of the spherical colloids is R.</li>
	<li>Extract R from the fits for each dispersion.</li>
	<li>Calculate the Rayleigh Ratio (R&#952;), which is an absolute measure for the intensity of the scattered light, according to the following equation, for each &#952;. 
	(Equation 4)<img alt="Equation 4" src="/files/ftp_upload/53934/53934eq4.jpg" />&#160; 
	 
	with the intensity of the sample, the solvent and the reference, Isample, Isolvent and Ireference respectively, the refractive index of the solvent and the reference nsolvent and nreference, correspondingly, and the Rayleigh Ratio of the reference Rreference. Here use toluene as a reference, such that nwater = 1.332, ntoluene = 1.497, ncyclohexane = 1.426; Rtoluene = 2.74x10-3 m-1 26.</li>
	<li>Compute the average refractive index of the colloids (ncolloids) from R&#952; and Equation 5. 
	(Equation 5)<img alt="Equation 5" src="/files/ftp_upload/53934/53934eq5.jpg" />&#160; 
	 
	with the number of particles per volume N, the volume of a particle vparticle given by vparticle =4/3&#960;R3, and assuming that the structure factor S(q)~1, which is the limit of non-interacting particles.</li>
</ol>
4. Quantification of the Number of Active Sites Per Particle
Note: Use small particles of 13 nm in radius (with a larger surface-to-volume ratio).
<ol>
	<li>Functionalize small commercially available particles with a 20/80 molar ratio of NVOC-C11-OH/stearyl alcohol following the procedure described in Section 2.1.</li>
	<li>Disperse 20 mg of the small, functionalized particles in 1 ml CHCl3 and irradiate the dispersion in a UV-oven (&#955;max=354 nm) for 1 hr to cleave the NVOC group. Stir the dispersion gently with a magnetic stirrer bar while deprotecting. In this manner the colloids do not sediment and their surface remains exposed to the UV light, hence ensuring homogeneous deprotection.</li>
	<li>Spin down the resulting amine-functionalized particles (3,400 x g, 10 min) and remove the supernatant.</li>
	<li>Dry the particles at 70 &#176;C for 2 hr.</li>
	<li>Dissolve 0.50 mg of succinimidyl 3-(2-pyridyldithio)propionate (SPDP, 0.0016 mmol) in 200 &#181;l of dimethylformamide (DMF).</li>
	<li>Add the SPDP solution to the 20 mg of the dried amine-functionalized particles and vortex the system for 30 min. Within this time, all available primary amines on the colloids have reacted with the SPDP.</li>
	<li>Wash the particles with 1 ml of DMF for 6 times (or until no free SPDP is detected in the supernatant by UV-Vis spectroscopy at &#955;=375 nm). In the last washing step try to remove as much supernatant as possible.</li>
	<li>Dissolve 0.53 mg of dithiothreitol (DTT, 0.0034 mmol) in 50 &#181;l of DMF. Add the DTT solution to the particles and vortex the dispersion for 30 min. Within this time the pyridine-2-thione group is cleaved.</li>
	<li>Determine the absorbance of the free pyridine-2-thione liberated in the supernatant at &#955;=293 nm with a microvolume UV-Vis spectrophotometer.</li>
	<li>Construct a calibration curve to determine the extinction coefficient &#603; (~12.1x103 M-1cm-1) of the pyridine-2-thione in DMF by measuring the absorbance of a dilution series of different known amounts of SPDP with an excess of DTT.</li>
	<li>Calculate the concentration of pyridine-2-thione, Cp2t, which is cleaved from the particles using the Lambert-Beer law: 
	(Equation 6) Abs = Cp2t &#949; l&#160;&#160;&#160;&#160; 
	with the molar concentration of pyridine-2-thione Cp2t, the extinction coefficient &#603; and the path length l.</li>
	<li>Calculate the number of active sites (amines) per particle with the following equation 
	(Equation 7)<img alt="Equation 7" src="/files/ftp_upload/53934/53934eq7.jpg" />&#160;&#160; &#160; &#160; &#160;&#160; &#160; 
	with the mass of one particle Mparticle that is Mparticle = 4/3&#960;R3&#961;, with &#961;=1.295 g/cm3, the total weighted mass of particles Mtotal (20 mg) and the total volume Vtotal (50 &#181;l). This equation assumes that all available amines react with the SPDP and the DTT reduces all SPDP molecules attached to the particles.</li>
</ol>
5. Monitor Colloidal Assembly by Confocal Microscopy
Note: Use core-shell silica particles (with a fluorescent core and a non-fluorescent shell).
<ol>
	<li>Prepare 400 &#181;l of a dispersion of 0.1 wt% of BTA-functionalized particles in cyclohexane and sonicate the sample for 20 min.</li>
	<li>Irradiate the sample vial in the UV oven (&#955;max = 354 nm) to cleave off the o-nitrobenzyl group of the BTA. Take 25 &#181;l aliquots at different times of irradiation, for example from 0 up to 30 min, to monitor the clustering process.</li>
	<li>Place the different aliquots on different glass slides with the help of a spacer and close the chambers with a cover slip (chamber size is 13 mm diameter &#215; 0.12 mm height). After closing the chamber, turn the cover slip upside down to let the particles sediment and adsorb onto the glass, which facilitates the imaging.</li>
	<li>Take several images of each sample with the confocal microscope as soon as possible after sample preparation for each irradiation time.</li>
</ol>
6. Image Analysis
<ol>
	<li>Quantification of the number of singlets with ImageJ 
	Note: All commands used to write the script are described in the ImageJ manual: 
	http://imagej.nih.gov/ij/docs/guide/user-guide.pdf
	<ol>
		<li>Smooth the confocal images to remove isolated pixels from the edges and fill small holes running the &#34;Smooth&#34; function.</li>
		<li>Given that only the cores are fluorescent, dilate the bright areas until the edge of the particles that belong to the same cluster touch and particles merge. Do this using the &#34;Dilate&#34; filter. With particles with approximately 180 nm shell thickness, and pictures with a resolution of 0.02 &#181;m/pixel, two dilation steps are enough.</li>
		<li>Convert the images into a binary picture running the &#34;Make binary&#34; function.</li>
		<li>Set the scale by running the tool &#34;&#34;Set Scale&#8230;&#34;, distance=1 known=0.02 pixel=1 unit=um&#34;&#34; for pictures taken with a resolution of 0.02 &#181;m/pixel for instance.</li>
		<li>Apply a threshold size to discriminate noise and out-of-focus particles from in-of-focus particles. For instance, with pictures taken with a resolution of 0.02 &#181;m/pixel, all areas smaller than 0.2 pixels are ruled out. Do this using the &#34;Analyze particles&#8230;&#34;, &#34;size=0.2-Infinity&#34; command.</li>
		<li>Create an all.jpg image and an all.txt file with the size of all bright areas in the image (clusters and singlets) by using the commands &#34;&#34;results&#34;, _all.txt&#34;&#34; and &#34;&#34;JPEG&#34;, &#34;all&#34;&#34;.</li>
		<li>Assume that all bright areas between 0.2 and 0.7 pixels in size and with a circularity (circularity = 4 &#960; Area/Perimeter2) between 0.7 and 1.0 are singlets running the command &#34;Analyze particles&#8230;&#34;, &#34;circularity=0.7-1.0&#34;.</li>
		<li>Create a singlets.jpg image and a singlets.txt file with the information of all bright areas that are singlets by using the commands &#34;&#34;results&#34;, _singlets.txt&#34;&#34; and &#34;&#34;JPEG&#34;, &#34;singlets&#34;&#34;.</li>
	</ol>
	</li>
	<li>Process the information with Matlab
	<ol>
		<li>Read the singlet .txt file and calculate the average size of a singlet per picture (Asinglet).</li>
		<li>Use the average size of a singlet to compute the number of particles per cluster (Adoublet=2Asinglet, Atriplet=3Asinglet &#8230;) and the total number of particles in the picture from the other all.txt file.</li>
		<li>Calculate the fraction of particles in singlets for each exposure time: fsinglets = number singlets/total particles</li>
		<li>Calculate the fraction of doublets, triplets, etc.: fdoublets= 2*number of doublets/total particles, etc.</li>
	</ol>
	</li>
</ol>

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Controlled growth reaction and continuous production process.</a> J. Eur. Ceram. Soc. 14 (3), 205-214 (1994).</li><li>Wu, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Correlations+between+the+Rayleigh+ratio+and+the+wavelength+for+toluene+and+benzene.">Correlations between the Rayleigh ratio and the wavelength for toluene and benzene.</a> Chem. Phys. 367 (1), 44-47 (2010).</li></ol>

The authors have nothing to disclose.

When cyclohexane, with a refractive index of 1.426, is used as a solvent to disperse the BTA-colloids, van der Waals interactions are very weak, since the refractive indices of colloids and solvent are nearly the same. Note that the concentration of functionalized colloids used for the SLS experiments in cyclohexane is much higher compared to the bare silica colloids in water. This is necessary to obtain a sufficiently strong scattering due to the low contrast as the refractive indices are almost matched. Trace amounts o...

Mesostructured colloidal materials find widespread application in science and technology, as model systems for fundamental studies on atomic and molecular materials1,2, as photonic materials3,4, as drug delivery systems5,6, as coatings7 and in lithography for surface patterning8,9. Since lyophobic colloids are metastable materials that eventually aggregate irreversibly due to the omnipresent van der Waals interactions, their manipulation into specific target structures is notoriously difficult. Numerous strategies have been developed to control colloidal self-assembly including the use of additives to tune the electrostatic10,11 or depletion interactions12,13, or external triggers such as magnetic14 or electric15 fields. A sophisticated alternative strategy to achieve control over the structure, dynamics and mechanics of these systems is their functionalization with molecules interacting through specific and directional forces. Supramolecular chemistry offers a comprehensive toolbox of small molecules exhibiting site-specific, directional and strong yet reversible interactions, which can be modulated in strength by solvent polarity, temperature and light16. Since their properties have been studied extensively in bulk and in solution, these molecules are attractive candidates to structure soft materials into exotic phases in a predictable manner. Despite the clear potential of such an integrated approach to orchestrate colloidal assembly via supramolecular chemistry, these disciplines have rarely interfaced to tailor the properties of mesostructured colloidal materials17,18.
A solid platform of supramolecular colloids must fulfill three main requirements. Firstly, coupling of the supramolecular moiety should be done under mild-conditions to prevent degradation. Secondly, surface forces at separations larger than direct contact should be dominated by the tethered motifs, which means that uncoated colloids should nearly exclusively interact via excluded-volume interactions. Therefore, the physico-chemical properties of the colloids should be tailored to suppress other interactions inherent in colloidal systems, such as van der Waals or electrostatic forces. Thirdly, characterization should allow for an unequivocal attribution of the assembly to the presence of the supramolecular moieties. To meet these three prerequisites, a robust two-step synthesis of supramolecular colloids was developed (Figure 1a). In a first step, hydrophobic NVOC-functionalized silica particles are prepared for dispersion in cyclohexane. The NVOC group can be easily cleaved, yielding amine-functionalized particles. The high reactivity of amines enables straightforward post-functionalization with the desired supramolecular moiety using a wide range of mild reaction conditions. Herein, we prepare supramolecular colloids by functionalization of silica beads with stearyl alcohol and a benzene-1,3,5-tricarboxamide (BTA) derivative20. The stearyl alcohol plays several important roles: it makes the colloids organophilic and it introduces short-range steric repulsions which aids to reduce the nonspecific interaction between colloids21,22. van der Waals forces are further reduced because of the close match between the refractive index of the colloids and the solvent23. Light-and thermoresponsive short-range attractive surface forces are generated by incorporation of o-nitrobenzyl protected BTAs20. O-nitrobenzyl moiety is a photo-cleavable group that blocks the formation of hydrogen bonds between adjacent BTAs when incorporated on the amides in the discotics (Figure 1b). Upon photocleavage by UV-light, the BTA in solution is able to recognize and interact with identical BTA molecules through a 3-fold hydrogen bond array, with a binding strength that is strongly temperature dependent17. Since the van der Waals attractions are minimal for stearyl coated silica particles in cyclohexane as well as light- and temperature-independent, the observed stimuli-responsive colloidal assembly must be BTA-mediated.
This detailed video demonstrates how to synthesize and characterize supramolecular colloids and how to study their self-assembly upon UV-irradiation by confocal microscopy. In addition, a simple image analysis protocol to distinguish colloidal singlets from clustered colloids and to determine the amount of colloids per clusters is reported. The versatility of the synthetic strategy allows to readily vary particle size, surface coverage as well as the introduced binding moiety, which opens up new avenues for the development of a large family of colloidal building blocks for mesostructured advanced materials.

<table border="0" cellpadding="0" cellspacing="0" width="1805">
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:524px;">APTES</td>
			<td style="width:128px;">Sigma-Aldrich</td>
			<td style="width:119px;"></td>
			<td style="width:1035px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:524px;">FTIC</td>
			<td style="width:128px;">Sigma-Aldrich</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:524px;">TEOS</td>
			<td style="width:128px;">Sigma-Aldrich</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:524px;">LUDOX AS-40</td>
			<td style="width:128px;">Sigma-Aldrich</td>
			<td style="width:119px;"></td>
			<td>Silica particles of 13 nm in radius</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:524px;">MilliQ</td>
			<td style="width:128px;">---</td>
			<td style="width:119px;">---</td>
			<td style="width:1035px;">18.2 M&#937;&#183;cm at 25 &#176;C</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:524px;">Ethanol</td>
			<td style="width:128px;">SolvaChrom</td>
			<td style="width:119px;"></td>
			<td style="width:1035px;">---</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:524px;">Ammonia (25% in water)</td>
			<td style="width:128px;">Sigma-Aldrich</td>
			<td style="width:119px;"></td>
			<td style="width:1035px;">---</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:524px;">Chloroform</td>
			<td style="width:128px;">SolvaChrom</td>
			<td style="width:119px;"></td>
			<td style="width:1035px;">---</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:524px;">Cyclohexane</td>
			<td style="width:128px;">Sigma-Aldrich</td>
			<td style="width:119px;"></td>
			<td style="width:1035px;">---</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:524px;">Dimethylformamide (DMF)</td>
			<td style="width:128px;">Sigma-Aldrich</td>
			<td style="width:119px;"></td>
			<td style="width:1035px;">---</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:524px;">Stearyl alcohol</td>
			<td style="width:128px;">Sigma-Aldrich</td>
			<td style="width:119px;"></td>
			<td style="width:1035px;">---</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">N,N-Diisopropylethylamine (DIPEA)</td>
			<td style="width:128px;">Sigma-Aldrich</td>
			<td style="width:119px;"></td>
			<td style="width:1035px;">---</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Benzotriazol-1-yl-oxytripyrrolidinophosphonium hexafluorophosphate (PyBOP)</td>
			<td style="width:128px;">Sigma-Aldrich</td>
			<td style="width:119px;"></td>
			<td style="width:1035px;">---</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Succinimidyl 3-(2-pyridyldithio)propionate (SPDP)</td>
			<td style="width:128px;">Sigma-Aldrich</td>
			<td style="width:119px;"></td>
			<td style="width:1035px;">---</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Dithiothreitol (DTT)&#160;</td>
			<td style="width:128px;">Sigma-Aldrich</td>
			<td style="width:119px;"></td>
			<td style="width:1035px;">---</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:524px;">NVOC-C11-OH</td>
			<td style="width:128px;">Synthesized</td>
			<td style="width:119px;">---</td>
			<td style="width:1035px;">I. de Feijter, 2014 Responsive materials from adaptive supramolecular constructs, Doctoral thesis, Technical University of Eindhoven, The Netherlands</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:524px;">BTA</td>
			<td style="width:128px;">Synthesized</td>
			<td style="width:119px;">---</td>
			<td style="width:1035px;">I. de Feijter, 2014 Responsive materials from adaptive supramolecular constructs, Doctoral thesis, Technical University of Eindhoven, The Netherlands</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:524px;">Centrifuge</td>
			<td style="width:128px;">Thermo Scientific</td>
			<td style="width:119px;"></td>
			<td>Heraeus Megafuge 1.0</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:524px;">Ultrasound bath</td>
			<td style="width:128px;">VWR</td>
			<td style="width:119px;"></td>
			<td>Ultrasonic cleaner</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Peristaltic pumps</td>
			<td>Harvard Apparatus</td>
			<td></td>
			<td>PHD Ultra Syringe Pump</td>
		</tr>
		<tr height="25">
			<td height="25" style="height:25px;width:524px;">UV-oven</td>
			<td style="width:128px;">Luzchem</td>
			<td style="width:119px;"></td>
			<td>LZC-a V UV reactor equipped with 8x8 UVA light bulbs (&#955;max=354 nm)</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:524px;">Stirrer-heating plate</td>
			<td style="width:128px;">Heidolph</td>
			<td style="width:119px;"></td>
			<td>MR-Hei Standard</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:524px;">Light Scattering</td>
			<td style="width:128px;">ALV</td>
			<td style="width:119px;"></td>
			<td>CGS-3 MD-4 compact goniometer system, equipped with a Multiple Tau digital real time correlator (ALV-7004) and a solid-state laser (&#955;=532 nm, 40 mW)</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">UV-Vis spectrophotometer</td>
			<td style="width:128px;">Thermo Scientific</td>
			<td style="width:119px;"></td>
			<td>NanoDrop 1000 Spectrophotometer</td>
		</tr>
		<tr height="25">
			<td height="25" style="height:25px;">Confocal microscope</td>
			<td style="width:128px;">Nikon</td>
			<td style="width:119px;"></td>
			<td>Ti Eclipse with an argon laser with &#955;excitation=488 nm</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:524px;">Slide spacers</td>
			<td style="width:128px;">Sigma-Aldrich</td>
			<td style="width:119px;"></td>
			<td>Grace BioLabs Secure seal imaging spacer (1 well, diam. &#215; thickness 13 mm &#215; 0.12 mm)</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:524px;">Syringes</td>
			<td style="width:128px;">BD Plastipak</td>
			<td style="width:119px;"></td>
			<td>20 mL syringe</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:524px;">Plastic tubing</td>
			<td style="width:128px;">SCI</td>
			<td style="width:119px;">BB31695-PE/5</td>
			<td>Ethylene oxide gas sterilizable micro medical tubing</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:524px;">Pulsating vortex mixer</td>
			<td style="width:128px;">VWR</td>
			<td style="width:119px;"></td>
			<td>Electrical: 120V, 50/60Hz, 150W Speed Range: 500&#8211;3000 rpm</td>
		</tr>
	</tbody>
</table>

synthesis and characterization of supramolecular colloids

Control over colloidal assembly is of utmost importance for the development of functional colloidal materials with tailored structural and mechanical properties for applications in photonics, drug delivery and coating technology. Here we present a new family of colloidal building blocks, coined supramolecular colloids, whose self-assembly is controlled through surface-functionalization with a benzene-1,3,5-tricarboxamide (BTA) derived supramolecular moiety. Such BTAs interact via directional, strong, yet reversible hydrogen-bonds with other identical BTAs. Herein, a protocol is presented that describes how to couple these BTAs to colloids and how to quantify the number of coupling sites, which determines the multivalency of the supramolecular colloids. Light scattering measurements show that the refractive index of the colloids is almost matched with that of the solvent, which strongly reduces the van der Waals forces between the colloids. Before photo-activation, the colloids remain well dispersed, as the BTAs are equipped with a photo-labile group that blocks the formation of hydrogen-bonds. Controlled deprotection with UV-light activates the short-range hydrogen-bonds between the BTAs, which triggers the colloidal self-assembly. The evolution from the dispersed state to the clustered state is monitored by confocal microscopy. These results are further quantified by image analysis with simple routines using ImageJ and Matlab. This merger of supramolecular chemistry and colloidal science offers a direct route towards light- and thermo-responsive colloidal assembly encoded in the surface-grafted monolayer.

&#160;Given that the two-step procedure used to synthesize the supramolecular colloids (Figure 1a), couples the BTA- derivatives (Figure 1b) in a second step at room temperature and in mild-reaction conditions, its stability is ensured.
<img alt="Figure 1" src="/files/ftp_upload/53934/53934fig1.jpg" /> 
Figure 1. Scheme of the synthesis of supramolecular colloids. A) Coupli...

Watch this Scientific Journal Video about Synthesis and Characterization of Supramolecular Colloids at JoVE.com

Synthesis and Characterization of Supramolecular Colloids

A protocol for the synthesis and characterization of colloids coated with supramolecular moieties is described. These supramolecular colloids undergo self-assembly upon the activation of the hydrogen-bonds between the surface-anchored molecules by UV-light.

Control over colloidal assembly is of utmost importance for the development of functional colloidal materials with tailored structural and mechanical ...

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9.6K 조회수.  Eindhoven University of Technology. A protocol for the synthesis and characterization of colloids coated with supramolecular moieties is described. These supramolecular colloids undergo self-assembly upon the activation of the hydrogen-bonds between the surface-anchored molecules by UV-light.

비디오: Synthesis and Characterization of Supramolecular Colloids

Split-and-pool Synthesis and Characterization of Peptide Tertiary Amide Library

Peptidomimetics are great sources of protein ligands. The oligomeric nature of these compounds enables us to access large synthetic libraries on solid phase by using combinatorial chemistry. One of the most well studied classes of peptidomimetics is peptoids. Peptoids are easy to synthesize and have been shown to be proteolysis-resistant and cell-permeable. Over the past decade, many useful protein ligands have been identified through screening of peptoid libraries. However, most of the ligands identified from peptoid libraries do not display high affinity, with rare exceptions. This may be due, in part, to the lack of chiral centers and conformational constraints in peptoid molecules. Recently, we described a new synthetic route to access peptide tertiary amides (PTAs). PTAs are a superfamily of peptidomimetics that include but are not limited to peptides, peptoids and N-methylated peptides. With side chains on both &#945;-carbon and main chain nitrogen atoms, the conformation of these molecules are greatly constrained by sterical hindrance and allylic 1,3 strain. (Figure 1) Our study suggests that these PTA molecules are highly structured in solution and can be used to identify protein ligands. We believe that these molecules can be a future source of high-affinity protein ligands. Here we describe the synthetic method combining the power of both split-and-pool and sub-monomer strategies to synthesize a sample one-bead one-compound (OBOC) library of PTAs.

Peptide tertiary amides (PTAs) are a superfamily of peptidomimetics that include but are not limited to peptides, peptoids and N-methylated peptides. Here we describe a synthetic method which combines&#160;both split-and-pool and sub-monomer strategies to synthesize a one-bead one-compound library of PTAs.

분할 및 풀 합성 펩타이드 급 아미드 도서관의 특성

Peptidomimetics are great sources of protein ligands. The oligomeric nature of these compounds enables us to access large synthetic libraries on solid ...

연구

화학

Nucleoside Triphosphates - From Synthesis to Biochemical Characterization

The traditional strategy for the introduction of chemical functionalities is the use of solid-phase synthesis by appending suitably modified phosphoramidite precursors to the nascent chain. However, the conditions used during the synthesis and the restriction to rather short sequences hamper the applicability of this methodology. On the other hand, modified nucleoside triphosphates are activated building blocks that have been employed for the mild introduction of numerous functional groups into nucleic acids, a strategy that paves the way for the use of modified nucleic acids in a wide-ranging palette of practical applications such as functional tagging and generation of ribozymes and DNAzymes. One of the major challenges resides in the intricacy of the methodology leading to the isolation and characterization of these nucleoside analogues.
	
	In this video article, we present a detailed protocol for the synthesis of these modified analogues using phosphorous(III)-based reagents. In addition, the procedure for their biochemical characterization is divulged, with a special emphasis on primer extension reactions and TdT tailing polymerization. This detailed protocol will be of use for the crafting of modified dNTPs and their further use in chemical biology.

The protocol described herein aims to explain and abridge the numerous obstacles in the way of the intricate route leading to modified nucleoside triphosphates. Consequently, this protocol facilitates both the synthesis of these activated building-blocks and their availability for practical applications.

뉴 클레오 사이드 트리 포스페이트 - 합성에서 생화학 적 특성에

The  traditional strategy for the introduction of chemical functionalities is the  use of solid-phase synthesis by appending suitably modified ...

Synthesis and Characterization of Functionalized Metal-organic Frameworks

Metal-organic frameworks have attracted extraordinary amounts of research attention, as they are attractive candidates for numerous industrial and technological applications. Their signature property is their ultrahigh porosity, which however imparts a series of challenges when it comes to both constructing them and working with them. Securing desired MOF chemical and physical functionality by linker/node assembly into a highly porous framework of choice can pose difficulties, as less porous and more thermodynamically stable congeners (e.g., other crystalline polymorphs, catenated analogues) are often preferentially obtained by conventional synthesis methods. Once the desired product is obtained, its characterization often requires specialized techniques that address complications potentially arising from, for example, guest-molecule loss or preferential orientation of microcrystallites. Finally, accessing the large voids inside the MOFs for use in applications that involve gases can be problematic, as frameworks may be subject to collapse during removal of solvent molecules (remnants of solvothermal synthesis). In this paper, we describe synthesis and characterization methods routinely utilized in our lab either to solve or circumvent these issues. The methods include solvent-assisted linker exchange, powder X-ray diffraction in capillaries, and materials activation (cavity evacuation) by supercritical CO2 drying. Finally, we provide a protocol for determining a suitable pressure region for applying the Brunauer-Emmett-Teller analysis to nitrogen isotherms, so as to estimate surface area of MOFs with good accuracy.

Synthesis, activation, and characterization of intentionally designed metal-organic framework materials is challenging, especially when building blocks are incompatible or unwanted polymorphs are thermodynamically favored over desired forms. We describe how applications of solvent-assisted linker exchange, powder X-ray diffraction in capillaries and activation via supercritical CO2 drying, can address some of these challenges.

기능화의 합성 및 특성 금속 - 유기 프레임 워크

Metal-organic frameworks have attracted extraordinary amounts of research attention, as they are attractive candidates for numerous industrial and ...

The Synthesis, Characterization and Reactivity of a Series of Ruthenium N-triphosPh Complexes

Herein we report the synthesis of a tridentate phosphine ligand N(CH2PPh2)3 (N-triphosPh) (1) via a phosphorus based Mannich reaction of the hydroxylmethylene phosphine precursor with ammonia in methanol under a nitrogen atmosphere. The N-triphosPh ligand precipitates from the solution after approximately 1 hr of reflux and can be isolated analytically pure via simple cannula filtration procedure under nitrogen. Reaction of the N-triphosPh ligand with [Ru3(CO)12] under reflux affords a deep red solution that show evolution of CO gas on ligand complexation. Orange crystals of the complex [Ru(CO)2{N(CH2PPh2)3}-&#954;3P] (2) were isolated on cooling to RT. The 31P{1H} NMR spectrum showed a characteristic single peak at lower frequency compared to the free ligand. Reaction of a toluene solution of complex 2 with oxygen resulted in the instantaneous precipitation of the carbonate complex [Ru(CO3)(CO){N(CH2PPh2)3}-&#954;3P] (3) as an air stable orange solid. Subsequent hydrogenation of 3 under 15 bar of hydrogen in a high-pressure reactor gave the dihydride complex [RuH2(CO){N(CH2PPh2)3}-&#954;3P] (4), which was fully characterized by X-ray crystallography and NMR spectroscopy. Complexes 3 and 4 are potentially useful catalyst precursors for a range of hydrogenation reactions, including biomass-derived products such as levulinic acid (LA). Complex 4 was found to cleanly react with LA in the presence of the proton source additive NH4PF6 to give [Ru(CO){N(CH2PPh2)3}-&#954;3P{CH3CO(CH2)2CO2H}-&#954;2O](PF6) (6).

The Synthesis, Characterization and Reactivity of a Series of Ruthenium N-triphosPh Complexes

Ruthenium phosphine complexes are widely used for homogeneous catalytic reactions such as hydrogenations. The synthesis of a series of novel tridentate ruthenium complexes bearing the N-triphos ligand N(CH2PPh2)3 is reported. Additionally, the stoichiometric reaction of a dihydride Ru&#8211;N-triphos complex with levulinic acid is described.

루테늄의 시리즈의 합성, 특성 및 반응성<em&gt; N</em&gt; -triphos<sup&gt; 박사</sup&gt; 단지

Herein we report the synthesis of a tridentate phosphine ligand N(CH2PPh2)3 (N-triphosPh) (1) via a phosphorus based Mannich reaction of the ...

Synthesis, Characterization, and Functionalization of Hybrid Au/CdS and Au/ZnS Core/Shell Nanoparticles

Plasmonic nanoparticles are an attractive material for light harvesting applications due to their easily modified surface, high surface area and large extinction coefficients which can be tuned across the visible spectrum. Research into the plasmonic enhancement of optical transitions has become popular, due to the possibility of altering and in some cases improving photo-absorption or emission properties of nearby chromophores such as molecular dyes or quantum dots. The electric field of the plasmon can couple with the excitation dipole of a chromophore, perturbing the electronic states involved in the transition and leading to increased absorption and emission rates. These enhancements can also be negated at close distances by energy transfer mechanism, making the spatial arrangement of the two species critical. Ultimately, enhancement of light harvesting efficiency in plasmonic solar cells could lead to thinner and, therefore, lower cost devices. The development of hybrid core/shell particles could offer a solution to this issue. The addition of a dielectric spacer between a gold nanoparticles and a chromophore is the proposed method to control the exciton plasmon coupling strength and thereby balance losses with the plasmonic gains. A detailed procedure for the coating of gold nanoparticles with CdS and ZnS semiconductor shells is presented. The nanoparticles show high uniformity with size control in both the core gold particles and shell species allowing for a more accurate investigation into the plasmonic enhancement of external chromophores.

The synthesis of uniform gold nanoparticles coated with semiconductor shells of CdS or ZnS is performed. The semiconductor coating is conducted by first depositing a silver sulfide shell and exchanging the silver cations for zinc or cadmium cations.

합성, 특성 및 하이브리드 금 / CD 및 금 /은 ZnS 코어 / 쉘 나노 입자의 작용 화

Plasmonic nanoparticles are an attractive material for light harvesting applications due to their easily modified surface, high surface area and large ...

Preparation of Carbon Nanosheets at Room Temperature

Amphiphilic molecules equipped with a reactive, carbon-rich "oligoyne" segment consisting of conjugated carbon-carbon triple bonds self-assemble into defined aggregates in aqueous media and at the air-water interface. In the aggregated state, the oligoynes can then be carbonized under mild conditions while preserving the morphology and the embedded chemical functionalization. This novel approach provides direct access to functionalized carbon nanomaterials. In this article, we present a synthetic approach that allows us to prepare hexayne carboxylate amphiphiles as carbon-rich siblings of typical fatty acid esters through a series of repeated bromination and Negishi-type cross-coupling reactions. The obtained compounds are designed to self-assemble into monolayers at the air-water interface, and we show how this can be achieved in a Langmuir trough. Thus, compression of the molecules at the air-water interface triggers the film formation and leads to a densely packed layer of the molecules. The complete carbonization of the films at the air-water interface is then accomplished by cross-linking of the hexayne layer at room temperature, using UV irradiation as a mild external stimulus. The changes in the layer during this process can be monitored with the help of infrared reflection-absorption spectroscopy and Brewster angle microscopy. Moreover, a transfer of the carbonized films onto solid substrates by the Langmuir-Blodgett technique has enabled us to prove that they were carbon nanosheets with lateral dimensions on the order of centimeters.

We present the synthesis of an amphiphilic hexayne and its use in the preparation of carbon nanosheets at the air-water interface from a self-assembled monolayer of these reactive, carbon-rich molecular precursors.

실내 온도에서 탄소 나노 시트의 제조

Amphiphilic molecules equipped with a reactive, carbon-rich "oligoyne" segment consisting of conjugated carbon-carbon triple bonds self-assemble into ...

Synthesis of Cyclic Polymers and Characterization of Their Diffusive Motion in the Melt State at the Single Molecule Level

We demonstrate a method for the synthesis of cyclic polymers and a protocol for characterizing their diffusive motion in a melt state at the single molecule level. An electrostatic self-assembly and covalent fixation (ESA-CF) process is used for the synthesis of the cyclic poly(tetrahydrofuran) (poly(THF)). The diffusive motion of individual cyclic polymer chains in a melt state is visualized using single molecule fluorescence imaging by incorporating a fluorophore unit in the cyclic chains. The diffusive motion of the chains is quantitatively characterized by means of a combination of mean-squared displacement (MSD) analysis and a cumulative distribution function (CDF) analysis. The cyclic polymer exhibits multiple-mode diffusion which is distinct from its linear counterpart. The results demonstrate that the diffusional heterogeneity of polymers that is often hidden behind ensemble averaging can be revealed by the efficient synthesis of the cyclic polymers using the ESA-CF process and the quantitative analysis of the diffusive motion at the single molecule level using the MSD and CDF analyses.

A protocol for the synthesis and characterization of diffusive motion of cyclic polymers at the single molecule level is presented.

단일 분자 수준에서 순환 고분자의 합성 및 용융 상태에서 그들의 확산 운동의 특성

We demonstrate a method for the synthesis of cyclic polymers and a protocol for characterizing their diffusive motion in a melt state at the single ...

Synthesis and Characterization of Fe-doped Aluminosilicate Nanotubes with Enhanced Electron Conductive Properties

The goal of the protocol is to synthesize Fe-doped aluminosilicate nanotubes of the imogolite type with the formula (OH)3Al2-xFexO3SiOH. Doping with Fe aims at lowering the band gap of imogolite, an insulator with the chemical formula (OH)3Al2O3SiOH, and at modifying its adsorption properties towards azo-dyes, an important class of organic pollutants of both wastewater and groundwater.
Fe-doped nanotubes are obtained in two ways: by direct synthesis, where FeCl3 is added to an aqueous mixture of the Si and Al precursors, and by post-synthesis loading, where preformed nanotubes are put in contact with a FeCl3&#8226;6H2O aqueous solution. In both synthesis methods, isomorphic substitution of Al3+ by Fe3+ occurs, preserving the nanotube structure. Isomorphic substitution is indeed limited to a mass fraction of ~1.0% Fe, since at a higher Fe content (i.e., a mass fraction of 1.4% Fe), Fe2O3 clusters form, especially when the loading procedure is adopted. The physicochemical properties of the materials are studied by means of X-ray powder diffraction (XRD), N2 sorption isotherms at -196 &#176;C, high resolution transmission electron microscopy (HRTEM), diffuse reflectance (DR) UV-Vis spectroscopy, and &#950;-potential measurements. The most relevant result is the possibility to replace Al3+ ions (located on the outer surface of the nanotubes) by post-synthesis loading on preformed imogolite without perturbing the delicate hydrolysis equilibria occurring during nanotube formation. During the loading procedure, an anionic exchange occurs, where Al3+ ions on the outer surface of the nanotubes are replaced by Fe3+ ions. In Fe-doped aluminosilicate nanotubes, isomorphic substitution of Al3+ by Fe3+ is found to affect the band gap of doped imogolite. Nonetheless, Fe3+ sites on the outer surface of nanotubes are able to coordinate organic moieties, like the azo-dye Acid Orange 7, through a ligand-displacement mechanism occurring in an aqueous solution.

Here, we present a protocol to synthesize and characterize Fe-doped aluminosilicate nanotubes. The materials are obtained by either sol-gel synthesis upon addition of FeCl3&#8226;6H2O to the mixture containing the Si and Al precursors or by post-synthesis ionic exchange of preformed aluminosilicate nanotubes.

향상된 전자 전도성 특성을 가진 철 - 도핑 된 알루미 노 실리케이트 나노 튜브의 합성 및 특성

The goal of the protocol is to synthesize Fe-doped aluminosilicate nanotubes of the imogolite type with the formula (OH)3Al2-xFexO3SiOH. Doping with Fe ...

Phase Behavior of Charged Vesicles Under Symmetric and Asymmetric Solution Conditions Monitored with Fluorescence Microscopy

Phase-separated giant unilamellar vesicles (GUVs) exhibiting coexisting liquid-ordered and liquid-disordered domains are a common biophysical tool to investigate the lipid raft hypothesis. Numerous studies, however, neglect the impact of physiological solution conditions. On that account, the current work presents the effect of high-salinity buffer and trans-membrane solution asymmetry on liquid-liquid phase separation in charged GUVs grown from dioleylphosphatidylglycerol, egg sphingomyelin, and cholesterol. The effects were studied under isothermal and varying temperature conditions.
We describe equipment and experimental strategies applicable for monitoring the stability of coexisting liquid domains in charged vesicles under symmetric and asymmetric high-salinity solution conditions. This includes an approach to prepare charged multicomponent GUVs in high-salinity buffer at high temperatures. The protocol entails the option to perform a partial exchange of the external solution by a simple dilution step while minimizing the vesicle dilution. An alternative approach is presented utilizing a microfluidic device that allows for a complete external solution exchange. The solution effects on phase separation were also studied under varying temperatures. To this end, we present the basic design and utility of an in-house built temperature control chamber. Furthermore, we reflect on the assessment of the GUV phase state, pitfalls associated with it and how to circumvent them.

Experiments on phase separated giant unilamellar vesicles (GUVs) frequently neglect physiological solution conditions. This work presents approaches to study the effect of high-salinity buffer on liquid-liquid phase separation in charged multicomponent GUVs as a function of trans-membrane solution asymmetry and temperature.

형광 현미경 검사 법으로 모니터링 하는 대칭 및 비대칭 솔루션 조건에서 충전된 Vesicles의 위상 동작

Phase-separated giant unilamellar vesicles (GUVs) exhibiting coexisting liquid-ordered and liquid-disordered domains are a common biophysical tool to ...

Protocol for the Solid-phase Synthesis of Oligomers of RNA Containing a 2'-O-thiophenylmethyl Modification and Characterization via Circular Dichroism

Solid-phase synthesis has been used to obtain canonical and modified polymers of nucleic acids, specifically of DNA or RNA, which has made it a popular methodology for applications in various fields and for different research purposes. The procedure described herein focuses on the synthesis, purification, and characterization of dodecamers of RNA 5&#39;-[CUA CGG AAU CAU]-3&#39; containing zero, one, or two modifications located at the C2&#39;-O-position. The probes are based on 2-thiophenylmethyl groups, incorporated into RNA nucleotides via standard organic synthesis and introduced into the corresponding oligonucleotides via their respective phosphoramidites. This report makes use of phosphoramidite chemistry via the four canonical nucleobases (Uridine (U), Cytosine (C), Guanosine (G), Adenosine (A)), as well as 2-thiophenylmethyl functionalized nucleotides modified at the 2&#39;-O-position; however, the methodology is amenable for a large variety of modifications that have been developed over the years. The oligonucleotides were synthesized on a controlled-pore glass (CPG) support followed by cleavage from the resin and deprotection under standard conditions, i.e., a mixture of ammonia and methylamine (AMA) followed by hydrogen fluoride/triethylamine/N-methylpyrrolidinone. The corresponding oligonucleotides were purified via polyacrylamide electrophoresis (20% denaturing) followed by elution, desalting, and isolation via reversed-phase chromatography (Sep-pak, C18-column). Quantification and structural parameters were assessed via ultraviolet-visible (UV-vis) and circular dichroism (CD) photometric analysis, respectively. This report aims to serve as a resource and guide for beginner and expert researchers interested in embarking in this field. It is expected to serve as a work-in-progress as new technologies and methodologies are developed. The description of the methodologies and techniques within this document correspond to a DNA/RNA synthesizer (refurbished and purchased in 2013) that uses phosphoramidite chemistry.

Protocol for the Solid-phase Synthesis of Oligomers of RNA Containing a 2'-O-thiophenylmethyl Modification and Characterization via Circular Dichroism

This article provides a detailed procedure on the solid-phase synthesis, purification, and characterization of dodecamers of RNA modified at the C2&#39;-O-position. UV-vis and circular dichroism photometric analyses are used to quantify and characterize structural aspects, i.e., single-strands or double-strands.

2&#39;- 포스 핀 올리고 뉴클레오타이드를 함유하는 올리고머의 고상 합성을위한 프로토콜<em&gt; O</em&gt; 원형 이색 성을 통한 - 티오 페닐 메틸 변형 및 특성 분석

Solid-phase synthesis has been used to obtain canonical and modified polymers of nucleic acids, specifically of DNA or RNA, which has made it a popular ...