Name: nanosponge tunability in size and crosslinking density
Uploaded: 2017-08-04T11:30:00
Description: Watch this Scientific Journal Video about Nanosponge Tunability in Size and Crosslinking Density at JoVE.com

LK is thankful for funding from the National Science Foundation Graduate Research Fellowship Program (DGE-1445197) and Vanderbilt University Chemistry Department. LK and EH would like to thank the funding for the Osiris TEM instrument (NSF EPS 1004083).

1. Synthesis and Characterization of AVL
<ol>
	<li>Place a magnetic stir bar inside a 2 neck 500 mL round bottom flask (Flask 1) and seal with an appropriate sized rubber septum and steel wire. Flame dry the flask to remove moisture by purging with nitrogen gas connected through an inlet needle and open outlet needle in the septum, while using a butane flame torch to gently heat the outside of the flask by moving the flame along the surface.
	<ol>
		<li>Continue heating the entire flask by running the ...

<ol>
	<li>van der Ende, A. E., Sathiyakumar, V., Diaz, R., Hallahan, D. E., Harth, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Linear+release+nanoparticle+devices+for+advanced+targeted+cancer+therapies+with+increased+efficacy.">Linear release nanoparticle devices for advanced targeted cancer therapies with increased efficacy.</a> Polym Chem. 1 (1), 93 (2010).</li><li>Sharma, S., Parmar, A., Kori, S., Sandhir, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=PLGA-based+nanoparticles:+A+new+paradigm+in+biomedical+applications.">PLGA-based nanoparticles: A new paradigm in biomedical applications.</a> Trends Anal Chem. 80, 30-40 (2016).</li><li>Cao, L. B., Zeng, S., Zhao, W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Highly+Stable+PEGylated+Poly(lactic-co-glycolic+acid)+(PLGA)+Nanoparticles+for+the+Effective+Delivery+of+Docetaxel+in+Prostate+Cancers.">Highly Stable PEGylated Poly(lactic-co-glycolic acid) (PLGA) Nanoparticles for the Effective Delivery of Docetaxel in Prostate Cancers.</a> Nanoscale Res Lett. 11 (1), 305 (2016).</li><li>Chelopo, M. P., Kalombo, L., Wesley-Smith, J., Grobler, A., Hayeshi, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+fabrication+and+characterization+of+a+PLGA+nanoparticle-Pheroid&#174;+combined+drug+delivery+system.">The fabrication and characterization of a PLGA nanoparticle-Pheroid&#174; combined drug delivery system.</a> J Mater Sci. 52 (6), 3133-3145 (2016).</li><li>Guan, Q., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Preparation,+in+vitro+and+in+vivo+evaluation+of+mPEG-PLGA+nanoparticles+co-loaded+with+syringopicroside+and+hydroxytyrosol.">Preparation, in vitro and in vivo evaluation of mPEG-PLGA nanoparticles co-loaded with syringopicroside and hydroxytyrosol.</a> J Mater Sci Mater Med. 27 (2), 24 (2016).</li><li>Cannava, C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Nanospheres+based+on+PLGA/amphiphilic+cyclodextrin+assemblies+as+potential+enhancers+of+Methylene+Blue+neuroprotective+effect.">Nanospheres based on PLGA/amphiphilic cyclodextrin assemblies as potential enhancers of Methylene Blue neuroprotective effect.</a> RSC Adv. 6, 16720-16729 (2016).</li><li>Locatelli, E., Franchini, M. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Biodegradable+PLGA-b-PEG+polymeric+nanoparticles:+synthesis,+properties,+and+nanomedical+applications+as+drug+delivery+system.">Biodegradable PLGA-b-PEG polymeric nanoparticles: synthesis, properties, and nanomedical applications as drug delivery system.</a> J Nanopart Res. 14 (12), (2012).</li><li>van der Ende, A. E., Croce, T., Hamilton, S., Sathiyakumar, V., Harth, E. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Tailored+polyester+nanoparticles:+post-modification+with+dendritic+transporter+and+targeting+units+via+reductive+amination+and+thiol-ene+chemistry.">Tailored polyester nanoparticles: post-modification with dendritic transporter and targeting units via reductive amination and thiol-ene chemistry.</a> Soft Matter. 5 (7), 1417 (2009).</li><li>Lockhart, J. N., Stevens, D. M., Beezer, D. B., Kravitz, A., Harth, E. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dual+drug+delivery+of+tamoxifen+and+quercetin:+Regulated+metabolism+for+anticancer+treatment+with+nanosponges.">Dual drug delivery of tamoxifen and quercetin: Regulated metabolism for anticancer treatment with nanosponges.</a> J Control Release. 220 (Pt. B), 751-757 (2015).</li><li>Shriner, R. L., Hermann, C. K. F., Morrill, T. C., Curtin, D. Y., Fuson, R. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> The Systematic Identification of Organic Compounds. , (2004).</li><li>Derome, A. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Modern NMR Techniques for Chemistry Research. , (1987).</li><li>Williams, D. B., Barry Carter, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Transmission Electron Microscopy: A Textbook for Materials Science. , (2009).</li><li>van der Ende, A. E., Kravitz, E. J., Harth, E. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Approach+to+Formation+of+Multifunctional+Polyester+Particles+in+Controlled+Nanoscopic+Dimensions.">Approach to Formation of Multifunctional Polyester Particles in Controlled Nanoscopic Dimensions.</a> J Am Chem. Soc. 130 (27), 8706-8713 (2008).</li><li>Stevens, D. M., Watson, H. A., LeBlanc, M. A., Wang, R. Y., Chou, J., Bauer, W. S., Harth, E. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Practical+polymerization+of+functionalized+lactones+and+carbonates+with+Sn(OTf)2+in+metal+catalysed+ring-+opening+polymerization+methods.">Practical polymerization of functionalized lactones and carbonates with Sn(OTf)2 in metal catalysed ring- opening polymerization methods.</a> Polym Chem. 4, 2470-2474 (2013).</li></ol>

Obtaining reproducible nanosponge sizes is vital in drug delivery applications. Multiple parameters in polymerization and nanosponge synthesis affect the size and crosslink density of the resulting particle. Three important parameters were identified in our analysis: polymer molecular weight, epoxide pendant functionality, and crosslinker equivalents. In order to produce a range of molecular weights and epoxide functionalities for nanosponge synthesis, the stoichiometry of the VL-co-AVL copolymer must be altered...

Precisely tuning the size and crosslinking density of nanoparticles based on intermolecular crosslinking is of great importance to influence and guide the drug release profile of these nanosystems1. Designing nanosponge tunability, i.e., preparing particles of different network densities, is reliant upon the pendant functionality of the precursor polymer and the equivalents of the hydrophilic crosslinker incorporated. In this approach, the concentration of the precursor and crosslinker in the solvent is important to form nanoparticles of a discrete size rather than a bulk gel. Utilizing quantitative nuclear magnetic resonance spectroscopy (NMR) as a characterization technique allows for the precise determination of incorporated pendant functionality and polymer molecular weight. Once nanoparticles are formed, they can be concentrated and solubilized in organics without having the character of a nanogel.
Recent work in nanoparticle drug delivery has focused on the use of poly(lactic-co-glycolic acid) (PLGA) self-assembled nanoparticles2,3,4,5,6. PLGA has degradable ester linkages which make it suitable for drug delivery applications and is often combined with poly(ethylene glycol) (PEG) due to its stealth properties7. However, due to the self-assembled nature of PLGA particle formation, the particles cannot be solubilized in organics for further functionalization. In contrast to PLGA nanoparticles, the proposed method provides covalent crosslinking forming a nanoparticle with defined sizes and morphology, which are stable in organics and degrade in aqueous solutions1. Advantages of this approach are the ability to further chemically functionalize the surface of the nanosponge8, and its stability in organic solvents can be used for the post-loading of the particles with pharmaceutical compounds1,9. With this method, encapsulation of hydrophobic small molecules can be achieved by precipitation into aqueous media. The hydrophobicity of the polyester backbone together with the hydrophilic short crosslinker gives these particles an amorphous character at body temperature. Furthermore, after drug loading, the particle can form fine suspensions in aqueous media to be readily injected in vivo. It is our goal in this work to evaluate the parameters for the synthesis of these polyester nanosponges and determine those which are vitally important to the design and control of size and morphology.

<table width="649">
	<tbody>
		<tr height="42">
			<td align="left" height="42" style="width:216px;height:42px;">2,2&#39;-(Ethylenedioxy)bis(ethylamine)</td>
			<td style="width:127px;">Sigma-Aldrich</td>
			<td style="width:119px;">385506-100ML</td>
			<td align="left" style="width:187px;"></td>
		</tr>
		<tr height="21">
			<td align="left" height="21" style="width:216px;height:21px;">3-methyl-1-butanol</td>
			<td style="width:127px;">Sigma-Aldrich</td>
			<td>309435-100ML</td>
			<td align="left" style="width:187px;">anhydrous, &#8805;99%</td>
		</tr>
		<tr height="21">
			<td align="left" height="21" style="width:216px;height:21px;">Acetone</td>
			<td style="width:127px;">Sigma-Aldrich</td>
			<td>179124-4L</td>
			<td align="left" style="width:187px;"></td>
		</tr>
		<tr height="21">
			<td align="left" height="21" style="width:216px;height:21px;">Allyl bromide</td>
			<td style="width:127px;">Sigma-Aldrich</td>
			<td>A29585-5G</td>
			<td align="left" style="width:187px;">&#8805;99%</td>
		</tr>
		<tr height="42">
			<td align="left" height="42" style="width:216px;height:42px;">Ammonium chloride</td>
			<td style="width:127px;">Fisher Scientific</td>
			<td>A661-500</td>
			<td align="left" style="width:187px;">saturated solution in DI water</td>
		</tr>
		<tr height="42">
			<td align="left" height="42" style="width:216px;height:42px;">Cell culture water</td>
			<td style="width:127px;">Sigma-Aldrich</td>
			<td>W3500-500ML</td>
			<td align="left" style="width:187px;">Filtered through 0.45 &#956;m syringe filter</td>
		</tr>
		<tr height="63">
			<td align="left" height="63" style="width:216px;height:63px;">Dichloromethane (DCM)</td>
			<td style="width:127px;">Sigma-Aldrich</td>
			<td>270997-100ML</td>
			<td align="left" style="width:187px;">anhydrous, &#8805;99%, contains 40-150 ppm amylene as stabilizer</td>
		</tr>
		<tr height="21">
			<td align="left" height="21" style="width:216px;height:21px;">Ethyl Acetate</td>
			<td style="width:127px;">Fisher Scientific</td>
			<td>E145SK-4</td>
			<td align="left" style="width:187px;"></td>
		</tr>
		<tr height="21">
			<td align="left" height="21" style="width:216px;height:21px;">EZFlow 0.2 &#956;m Syringe Filter</td>
			<td style="width:127px;">Foxx Life Sciences</td>
			<td>386-2116-OEM</td>
			<td align="left" style="width:187px;">Hydrophillic PTFE, 13 mm</td>
		</tr>
		<tr height="21">
			<td align="left" height="21" style="width:216px;height:21px;">EZFlow 0.45 &#956;m Syringe Filter</td>
			<td style="width:127px;">Foxx Life Sciences</td>
			<td>386-3126-OEM</td>
			<td align="left" style="width:187px;">Hydrophillic PTFE, 25 mm</td>
		</tr>
		<tr height="63">
			<td align="left" height="63" style="width:216px;height:63px;">Fisherbrand Disposable Borosilicate Glass Test Tubes with Plain End</td>
			<td style="width:127px;">Fisher Scientific</td>
			<td>14-961-31</td>
			<td align="left" style="width:187px;"></td>
		</tr>
		<tr height="42">
			<td align="left" height="42" style="width:216px;height:42px;">Fisherbrand Microcentrifuge Tubes</td>
			<td style="width:127px;">Fisher Scientific</td>
			<td>14-666-318</td>
			<td align="left" style="width:187px;">1.5 mL</td>
		</tr>
		<tr height="63">
			<td align="left" height="63" style="width:216px;height:63px;">Hamilton Microliter Syringe, 100 &#956;L</td>
			<td style="width:127px;">Hamilton Company</td>
			<td>80600</td>
			<td align="left" style="width:187px;">Model 710 N SYR, Cemented NDL, 22s ga, 2 in, point style 2</td>
		</tr>
		<tr height="63">
			<td align="left" height="63" style="width:216px;height:63px;">Hexamethylphosphoramide</td>
			<td style="width:127px;">Sigma-Aldrich</td>
			<td>H11602-100G</td>
			<td align="left" style="width:187px;">&#8805;99%, contains &#8804;1000 ppm propylene oxide as stabilizer</td>
		</tr>
		<tr height="21">
			<td align="left" height="21" style="width:216px;height:21px;">Hexanes</td>
			<td style="width:127px;">Fisher Scientific</td>
			<td>H292-4</td>
			<td align="left" style="width:187px;"></td>
		</tr>
		<tr height="21">
			<td align="left" height="21" style="width:216px;height:21px;">Magnesium sulfate anhydrous</td>
			<td style="width:127px;">Fisher Scientific</td>
			<td>M65-500</td>
			<td align="left" style="width:187px;"></td>
		</tr>
		<tr height="42">
			<td align="left" height="42" style="width:216px;height:42px;">Meta-chloroperoxybenzoic acid</td>
			<td style="width:127px;">Sigma-Aldrich</td>
			<td>273031-100G</td>
			<td align="left" style="width:187px;">Purified to &#8805;99% by buffer wash</td>
		</tr>
		<tr height="21">
			<td align="left" height="21" style="width:216px;height:21px;">Methanol (MeOH)</td>
			<td style="width:127px;">Sigma-Aldrich</td>
			<td>322415-100ML</td>
			<td align="left" style="width:187px;">anhydrous, &#8805;99%</td>
		</tr>
		<tr height="21">
			<td align="left" height="21" style="width:216px;height:21px;">N-butyllithium solution</td>
			<td style="width:127px;">Sigma-Aldrich</td>
			<td>230707-100ML</td>
			<td align="left" style="width:187px;">2.5 M in hexanes</td>
		</tr>
		<tr height="21">
			<td align="left" height="21" style="width:216px;height:21px;">N,N-diisopropylethylamine</td>
			<td style="width:127px;">Sigma-Aldrich</td>
			<td>550043-500ML</td>
			<td align="left" style="width:187px;">&#8805;99%</td>
		</tr>
		<tr height="21">
			<td align="left" height="21" style="width:216px;height:21px;">Parafilm M</td>
			<td style="width:127px;">Sigma-Aldrich</td>
			<td>P7793-1EA</td>
			<td align="left" style="width:187px;"></td>
		</tr>
		<tr height="42">
			<td align="left" height="42" style="width:216px;height:42px;">PELCO Pro Reverse (Self-Closing) Tweezers</td>
			<td style="width:127px;">Ted Pella, Inc.</td>
			<td>5375-NM</td>
			<td align="left" style="width:187px;"></td>
		</tr>
		<tr height="21">
			<td align="left" height="21" style="width:216px;height:21px;">Phosphotungstic acid hydrate</td>
			<td style="width:127px;">Alfa Aesar</td>
			<td>40116</td>
			<td align="left" style="width:187px;"></td>
		</tr>
		<tr height="21">
			<td align="left" height="21" style="width:216px;height:21px;">Q55 Sonicator</td>
			<td style="width:127px;">Qsonica</td>
			<td>Q55-110</td>
			<td align="left" style="width:187px;">55 Watts, 20 kHz</td>
		</tr>
		<tr height="21">
			<td align="left" height="21" style="width:216px;height:21px;">SiliaMetS Cysteine</td>
			<td style="width:127px;">Silicycle</td>
			<td>R80530B-10g</td>
			<td align="left" style="width:187px;"></td>
		</tr>
		<tr height="21">
			<td align="left" height="21" style="width:216px;height:21px;">SnakeSkin Dialysis Clips</td>
			<td style="width:127px;">Thermo Scientific</td>
			<td>68011</td>
			<td align="left" style="width:187px;"></td>
		</tr>
		<tr height="42">
			<td align="left" height="42" style="width:216px;height:42px;">SnakeSkin Dialysis Tubing, 10K MWCO</td>
			<td style="width:127px;">Thermo Scientific</td>
			<td>68100</td>
			<td align="left" style="width:187px;"></td>
		</tr>
		<tr height="42">
			<td align="left" height="42" style="width:216px;height:42px;">Sodium bicarbonate</td>
			<td style="width:127px;">Fisher Scientific</td>
			<td>5233-500</td>
			<td align="left" style="width:187px;">saturated solution in DI water</td>
		</tr>
		<tr height="84">
			<td align="left" height="84" style="width:216px;height:84px;">TEM grid</td>
			<td style="width:127px;">Ted Pella, Inc.</td>
			<td>01822-F</td>
			<td align="left" style="width:187px;">Ultrathin Carbon Type-A, 400 mesh, Copper, approx. grid hole size: 42&#181;m</td>
		</tr>
		<tr height="42">
			<td align="left" height="42" style="width:216px;height:42px;">Tetrahydrofuran (THF)</td>
			<td style="width:127px;">Sigma-Aldrich</td>
			<td>401757-1L</td>
			<td align="left" style="width:187px;">Anhydrous, &#8805;99.9%, inhibitor-free</td>
		</tr>
		<tr height="42">
			<td align="left" height="42" style="width:216px;height:42px;">Tin(II) trifluoromethanesulfonate</td>
			<td style="width:127px;">Sigma-Aldrich</td>
			<td>388122-1G</td>
			<td align="left" style="width:187px;"></td>
		</tr>
		<tr height="42">
			<td align="left" height="42" style="width:216px;height:42px;">Vortex-Genie 2</td>
			<td style="width:127px;">Scientific Industries</td>
			<td>SI-0236</td>
			<td align="left" style="width:187px;"></td>
		</tr>
		<tr height="21">
			<td align="left" height="21" style="width:216px;height:21px;">Whatman Filter Paper, Grade 1</td>
			<td style="width:127px;">Fisher Scientific</td>
			<td>09-805H</td>
			<td align="left" style="width:187px;">Circles, 185 mm</td>
		</tr>
		<tr height="42">
			<td align="left" height="42" style="width:216px;height:42px;">&#948;-valerolactone</td>
			<td style="width:127px;">Sigma-Aldrich</td>
			<td>389579-100ML</td>
			<td align="left" style="width:187px;">Purified by vacuum distillation</td>
		</tr>
	</tbody>
</table>

nanosponge tunability in size and crosslinking density

We describe a protocol for the synthesis of linear polyesters containing pendant epoxide functionality and their incorporation into a nanosponge with controlled dimensions. This approach begins with synthesis of a functionalized lactone which is key to the pendant functionalization of the resulting polymer. Valerolactone (VL) and allyl-valerolactone (AVL) are then copolymerized using ring-opening polymerization. Post-polymerization modification is then used to install an epoxide moiety on some or all of the pendant allyl groups. Epoxy-amine chemistry is employed to form nanoparticles in a dilute solution of both polymer and small molecule diamine crosslinker based on the desired nanosponge size and crosslinking density. Nanosponge sizes can be characterized by transmission electron microscopy (TEM) imaging to determine the dimension and distribution. This method provides a pathway by which highly tunable polyesters can create tunable nanoparticles, which can be used for small molecule drug encapsulation. Due to the nature of the backbone, these particles are hydrolytically and enzymatically degradable for a controlled release of a wide range of hydrophobic small molecules.

To evaluate the relationship between the synthesis parameters of the nanosponge and its resultant size, the concentration and pendant functionality of each polymer precursor is important. In Figure 1, a successfulsynthetic scheme of nanosponges is carried out under reflux conditions after incorporating both precursor polymer and diamine crosslinker in DCM for 12 h. The concentration of epoxides in the solution is also critical to forming discrete particles. O...

Watch this Scientific Journal Video about Nanosponge Tunability in Size and Crosslinking Density at JoVE.com

Nanosponge Tunability in Size and Crosslinking Density

This article describes a process for tuning the size and crosslinking density of covalently crosslinked nanoparticles from linear polyesters containing pendant functionality. By tailoring synthesis parameters (polymer molecular weight, pendant functionality incorporation, and crosslinker equivalents), a desired nanoparticle size and crosslinking density can be achieved for drug delivery applications.

We describe a protocol for the synthesis of linear polyesters containing pendant epoxide functionality and their incorporation into a nanosponge with ...

Research

Education

JoVE Journal

JoVE Core

Organic Chemistry

Chemistry

Unit 1

Ethers, Epoxides, Sulfides

SCIENTISTS IN ACTION

A Simple Method for the Size Controlled Synthesis of Stable Oligomeric Clusters of Gold Nanoparticles under Ambient Conditions

Reducing dilute aqueous HAuCl4 with sodium thiocyanate (NaSCN) under alkaline conditions produces 2 to 3 nm diameter nanoparticles. Stable grape-like ...

Radiolabeling and Quantification of Cellular Levels of Phosphoinositides by High Performance Liquid Chromatography-coupled Flow Scintillation

Phosphoinositides (PtdInsPs) are essential signaling lipids responsible for recruiting specific effectors and conferring organelles with molecular ...

Flow-pattern Guided Fabrication of High-density Barcode Antibody Microarray

Antibody microarray as a well-developed technology is currently challenged by a few other established or emerging high-throughput technologies. In this ...

Standards for Quantitative Metalloproteomic Analysis Using Size Exclusion ICP-MS

Metals are essential for protein function as cofactors to catalyze chemical reactions. Disruption of metal homeostasis is implicated in a number of ...

Sequencing of Plant Wall Heteroxylans Using Enzymic, Chemical (Methylation) and Physical (Mass Spectrometry, Nuclear Magnetic Resonance) Techniques

Sequencing of Plant Wall Heteroxylans Using Enzymic, Chemical Methylation and Physical Mass Spectrometry, Nuclear Magnetic Resonance Techniques

This protocol describes the specific techniques used for the characterization of reducing end (RE) and internal region glycosyl sequence(s) of ...

Measurement of Particle Size Distribution in Turbid Solutions by Dynamic Light Scattering Microscopy

A protocol for measuring polydispersity of concentrated polymer solutions using dynamic light scattering is described. Dynamic light scattering is a ...

DNA-magnetic Particle Binding Analysis by Dynamic and Electrophoretic Light Scattering

Isolation of DNA using magnetic particles is a field of high importance in biotechnology and molecular biology research. This protocol describes the ...

Optimizing the Genetic Incorporation of Chemical Probes into GPCRs for Photo-crosslinking Mapping and Bioorthogonal Chemistry in Live Mammalian Cells

The genetic incorporation of non-canonical amino acids (ncAAs) via amber stop codon suppression is a powerful technique to install artificial probes and ...

Bio-inspired Polydopamine Surface Modification of Nanodiamonds and Its Reduction of Silver Nanoparticles

Surface functionalization of nanodiamonds (NDs) is still challenging due to the diversity of functional groups on the ND surfaces. Here, we demonstrate a ...

Multiscale Sampling of a Heterogeneous Water/Metal Catalyst Interface using Density Functional Theory and Force-Field Molecular Dynamics

A significant number of heterogeneously-catalyzed chemical processes occur under liquid conditions, but simulating catalyst function under such conditions ...