Name: cn-gelfree - clear native gel-eluted liquid fraction entrapment electrophoresis
Uploaded: 2016-02-29T14:00:00
Description: Watch this Scientific Journal Video about CN-GELFrEE - Clear Native Gel-eluted Liquid Fraction Entrapment Electrophoresis at JoVE.com

The W. M. Keck Foundation generously provided funding for this work. This material is based upon work supported by FAPERJ research grant 100.039/2014 from the government of Rio de Janeiro State - Brazil for R.D.M., Science Without Borders scholarship 88888.075416/2013-00 from the Coordination for the Improvement of Higher Education Personnel, under the government of Brazil, for H.S.S., the National Science Foundation Graduate Research Fellowship under fellowship number 2014171659 for O.S.S., and by CNPq research grant 202011/2012-7 from the government of Brazil for L.H.F.D.V. P.C.H. is a recipient of a Northwestern University&#39;s Chemistry of Life Processes Institute Postdoctoral Fellowship Award.

Note: This video protocol is based on an associated publication9. Specific reagents, material and equipment necessary to perform all the steps described in this protocol are listed in the materials section. The recipes and information for preparation of all required solutions are itemized in Table 1.
1. Pouring of Gradient Tube Gels
<ol>
	<li>Assembling the Casting System
	<ol>
		<li>Using a flame-heated razor blade or scalpel, cut a 20 ml serological pipette alon...

<ol>
	<li>Alberts, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+Cell+as+a+Collection+of+Protein+Machines:+Preparing+the+Next+Generation+of+Molecular+Biologists.">The Cell as a Collection of Protein Machines: Preparing the Next Generation of Molecular Biologists.</a> Cell. 92 (3), 291-294 (1998).</li><li>Gingras, A. C., Gstaiger, M., Raught, B., Aebersold, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Analysis+of+protein+complexes+using+mass+spectrometry.">Analysis of protein complexes using mass spectrometry.</a> Nat. Rev. Mol. Cell Biol. 8 (8), 645-654 (2007).</li><li>Gavin, A. C., B&#246;sche, M., 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=Functional+organization+of+the+yeast+proteome+by+systematic+analysis+of+protein+complexes.">Functional organization of the yeast proteome by systematic analysis of protein complexes.</a> Nature. 415 (6868), 141-147 (2002).</li><li>Puig, O., Caspary, F., 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=The+Tandem+Affinity+Purification+(TAP)+Method:+A+General+Procedure+of+Protein+Complex+Purification.">The Tandem Affinity Purification (TAP) Method: A General Procedure of Protein Complex Purification.</a> Methods. 24 (3), 218-229 (2001).</li><li>Cremer, K. D., Hulle, M. V., 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=Fractionation+of+vanadium+complexes+in+serum,+packed+cells+and+tissues+of+Wistar+rats+by+means+of+gel+filtration+and+anion-exchange+chromatography.">Fractionation of vanadium complexes in serum, packed cells and tissues of Wistar rats by means of gel filtration and anion-exchange chromatography.</a> JBIC J. Biol. Inorg. Chem. 7 (7-8), 884-890 (2002).</li><li>Tanese, N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Small-Scale+Density+Gradient+Sedimentation+to+Separate+and+Analyze+Multiprotein+Complexes.">Small-Scale Density Gradient Sedimentation to Separate and Analyze Multiprotein Complexes.</a> Methods. 12 (3), 224-234 (1997).</li><li>Bunai, K., Yamane, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effectiveness+and+limitation+of+two-dimensional+gel+electrophoresis+in+bacterial+membrane+protein+proteomics+and+perspectives.">Effectiveness and limitation of two-dimensional gel electrophoresis in bacterial membrane protein proteomics and perspectives.</a> J. Chromatogr. B. 815 (1-2), 227-236 (2005).</li><li>Wittig, I., Sch&#228;gger, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Advantages+and+limitations+of+clear-native+PAGE.">Advantages and limitations of clear-native PAGE.</a> PROTEOMICS. 5 (17), 4338-4346 (2005).</li><li>Skinner, O. S., Do Vale, L. H. F., 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=Native+GELFrEE:+A+New+Separation+Technique+for+Biomolecular+Assemblies.">Native GELFrEE: A New Separation Technique for Biomolecular Assemblies.</a> Anal. Chem. 87 (5), 3032-3038 (2015).</li><li>Nijtmans, L. G. J., Henderson, N. S., Holt, I. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Blue+Native+electrophoresis+to+study+mitochondrial+and+other+protein+complexes.">Blue Native electrophoresis to study mitochondrial and other protein complexes.</a> Methods. 26 (4), 327-334 (2002).</li><li>Tran, J. C., Doucette, A. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Gel-Eluted+Liquid+Fraction+Entrapment+Electrophoresis:+An+Electrophoretic+Method+for+Broad+Molecular+Weight+Range+Proteome+Separation.">Gel-Eluted Liquid Fraction Entrapment Electrophoresis: An Electrophoretic Method for Broad Molecular Weight Range Proteome Separation.</a> Anal. Chem. 80 (5), 1568-1573 (2008).</li><li>Smith, P. K., Krohn, R. I., 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=Measurement+of+protein+using+bicinchoninic+acid.">Measurement of protein using bicinchoninic acid.</a> Anal. Biochem. 150 (1), 76-85 (1985).</li></ol>

CN-GELFrEE is derived from the clear native (CN) PAGE buffer system that uses a mixture of anionic and neutral detergents as carrier molecules9 for molecular-weight-based protein fractionation through a gel matrix. The application of CN-GELFrEE to a native mouse heart protein extract generated low complexity fractions with discrete bandwidths while maintaining non-covalent interactions of biomolecular assemblies. Comparison of fractions between CN-PAGE and reducing SDS-PAGE slab gels showed mass shifts that de...

The majority of biological processes happening within a cell are thought to be carried out by protein assemblies rather than single proteins1. Consequently, in order to elucidate the specific biological role of a protein subunit in a cell it is necessary to understand its structural interactions with other proteins or ligands in complexes2. However, studying proteins natively, maintaining their non-covalent interactions and activity, remains challenging. One of the shortcomings of native protein studies is a suitable native separation technique that is compatible with various downstream protein analysis techniques. Therefore, recent interest in separation techniques capable of characterizing non-covalent assemblies of biomolecules has increased sharply3.
Protein separation techniques are imperative to biochemistry, biophysics and various other studies. Current native separation techniques have intrinsic deficiencies that reduce compatibility with downstream analyses, such as low resolution, low throughput, loss to precipitation, and the requirement of large amounts of initial sample. Tandem affinity purification is commonly used for protein interaction studies, but it has to be carried out separately for each protein target, causing it to be incompatible with high-throughput analysis4. Size exclusion chromatography5, selective precipitation with ion affinity chromatography5 and density-gradient separation6 all have provided native separations, but are inherently low-resolution techniques and require high initial sample amounts.
Alternatively, gel-based techniques, such as Blue Native (BN) and Clear Native (CN) PAGE (either 1-D or 2-D), display high-resolution separation. Furthermore, contrasting with other techniques mentioned, both native PAGE separations maintain solubility and native conformation of a broad range of macromolecule species, including hydrophobic proteins. This capability further broadens the proteome coverage reached by these methods7,8 and is achieved through different chemistry between CN and BN-PAGE. CN-PAGE commonly relies on soft charged detergents as carrier molecules, replacing the Coomassie Blue dye in BN-PAGE. BN-PAGE, although associated with higher resolution, has caveats such as reduced enzymatic activity in the separated proteins8 and Coomassie molecule adduct formation, the latter being greatly prejudicial to downstream MS analyses9. Both these methods, however, are traditionally associated with low recovery and narrow proteome coverage due to staining and gel extraction limitations7.
For the study of denatured proteins, there are several techniques that maintain macromolecule solubility while performing high-resolution fractionation with high protein recovery and that are compatible with diverse post-separation protein analysis techniques. Gel-Eluted Liquid Fraction Entrapment Electrophoresis (GELFrEE) is one of the fractionation techniques that fit all these characteristics. This method is largely applied in high-throughput top-down proteomics studies, indicating that it is fast and versatile. In GELFrEE, proteins are denatured and separated based on molecular weight through a tubular gel matrix, the porosity of which can be varied based on sample requirements and the desired fractionation results. Fractions are eluted in liquid phase, thus reducing the recovery limitations associated with SDS-PAGE while maintaining high resolution. Fraction aliquots can then be analyzed by 1-D PAGE for molecular-weight bandwidth selection11. There is high demand for the advantages associated with GELFrEE in native separation techniques. The method described herein, Clear Native GELFrEE (CN-GELFrEE), is a native adaptation of GELFrEE. In order to be compatible with a broad spectrum of macromolecules in their native state, this method relies not only on the soft CN-PAGE chemistry, but also on a porosity gradient separation, which reduces protein precipitation by eliminating the harsh transition between porosities present in discontinuous gel systems9. When applied to fractionate protein complexes extracted from mouse heart, eluted fractions displayed high recovery and a high-resolution separation of a wide range of molecular weights was obtained. Further, the resulting fractions are compatible with most downstream biochemical and biophysical protein analyses.

<table border="0" cellpadding="0" cellspacing="0" width="820">
	<tbody>
		<tr height="21">
			<td colspan="4" height="21" style="height:21px;width:820px;">Reagents</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:276px;">30% acrylamide/bis solution, 37.5:1</td>
			<td style="width:176px;">Bio-Rad</td>
			<td style="width:119px;">161-0158</td>
			<td style="width:249px;">This solution is neurotoxic.</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:276px;">6-aminohexanoic acid (&#949;-aminocaproic acid)</td>
			<td style="width:176px;">Sigma-Aldrich</td>
			<td style="width:119px;">A2504</td>
			<td style="width:249px;">This chemical is an irritant.</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:276px;">Ammonium persulfate (APS)</td>
			<td style="width:176px;">Fisher Scientific</td>
			<td style="width:119px;">7727-54-0</td>
			<td style="width:249px;">This chemical is flammable, toxic, and corrosive.</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:276px;">Coomassie blue G250</td>
			<td style="width:176px;">Bio-Rad</td>
			<td style="width:119px;">161-0406</td>
			<td style="width:249px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:276px;">Dodecylmaltoside</td>
			<td style="width:176px;">Sigma-Aldrich</td>
			<td style="width:119px;">D4641</td>
			<td style="width:249px;">This chemical is an irritant.</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:276px;">Ethylene glycol tetraacetic acid (EGTA)</td>
			<td style="width:176px;">FLUKA</td>
			<td style="width:119px;">3777</td>
			<td style="width:249px;">This chemical is toxic.</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:276px;">Ethylenediamine tetraacetic acid (EDTA)</td>
			<td style="width:176px;">Fisher Scientific</td>
			<td style="width:119px;">BP120</td>
			<td style="width:249px;">This chemical is toxic.</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:276px;">Glycerol</td>
			<td style="width:176px;">Fisher Scientific</td>
			<td style="width:119px;">56-81-5</td>
			<td style="width:249px;"></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:276px;">Imidazole</td>
			<td style="width:176px;">Sigma-Aldrich</td>
			<td style="width:119px;">I2399</td>
			<td style="width:249px;"></td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:276px;">Liquid nitrogen</td>
			<td style="width:176px;">Any supplier</td>
			<td style="width:119px;">n/a</td>
			<td style="width:249px;">Store liquid nitrogen in containers 
			designed for low-temperature 
			liquids</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:276px;">Mouse heart</td>
			<td style="width:176px;">Bioreclamation LLC</td>
			<td style="width:119px;">MSE-HEART</td>
			<td style="width:249px;"></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:276px;">n-butanol</td>
			<td style="width:176px;">Fisher Scientific</td>
			<td style="width:119px;">71-36-3</td>
			<td style="width:249px;">This chemical is flammable and toxic.</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:276px;">Ponceau S</td>
			<td style="width:176px;">Sigma-Aldrich</td>
			<td style="width:119px;">BP103</td>
			<td style="width:249px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:276px;">Protease Inhibitor Cocktail</td>
			<td style="width:176px;">Thermo Fisher Scientific</td>
			<td style="width:119px;">78430</td>
			<td style="width:249px;">This chemical is toxic.</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:276px;">Sodium deoxycholate</td>
			<td style="width:176px;">Sigma-Aldrich</td>
			<td style="width:119px;">30970</td>
			<td style="width:249px;">This chemical is an irritant.</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:276px;">Sucrose</td>
			<td style="width:176px;">JTBaker</td>
			<td style="width:119px;">4097</td>
			<td style="width:249px;"></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:276px;">Tetramethylethylenediamine (TEMED)</td>
			<td style="width:176px;">Bio-Rad</td>
			<td style="width:119px;">161-0800</td>
			<td style="width:249px;">This chemical flammable and irritant.</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:276px;">Tris-HCl</td>
			<td style="width:176px;">Amresco</td>
			<td style="width:119px;">M151</td>
			<td style="width:249px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:276px;">Trycine</td>
			<td style="width:176px;">Bio-Rad</td>
			<td style="width:119px;">161-071</td>
			<td style="width:249px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:276px;">Name</td>
			<td style="width:176px;">Company</td>
			<td style="width:119px;">Catalog Number</td>
			<td>Comments</td>
		</tr>
		<tr height="21">
			<td colspan="4" height="21" style="height:21px;width:820px;">Equipment</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:276px;">Gradient mixer</td>
			<td style="width:176px;">Hoefer</td>
			<td style="width:119px;">SG15</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:276px;">Magnetic stir&#160;</td>
			<td style="width:176px;">Any supplier</td>
			<td style="width:119px;">n/a</td>
			<td style="width:249px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:276px;">Magnetic bars&#160;</td>
			<td style="width:176px;">Any supplier</td>
			<td style="width:119px;">n/a</td>
			<td style="width:249px;">Small enough to fit inside the gradiet mixer chambers.</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:276px;">Power supply</td>
			<td style="width:176px;">Bio-Rad</td>
			<td style="width:119px;">164-5056</td>
			<td>Voltage up to 1,500 V</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:276px;">Refrigerated centrifugue</td>
			<td style="width:176px;">Eppendorf</td>
			<td style="width:119px;">022622552</td>
			<td>Up to 15,000 x g</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:276px;">Name</td>
			<td style="width:176px;">Company</td>
			<td style="width:119px;">Catalog Number</td>
			<td>Comments</td>
		</tr>
		<tr height="21">
			<td colspan="4" height="21" style="height:21px;width:820px;">Materials</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:276px;">15 mL conical tube</td>
			<td style="width:176px;">Any supplier</td>
			<td style="width:119px;">n/a</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:276px;">30-kDa-MWCO ultra centrifugal filter</td>
			<td style="width:176px;">Millipore</td>
			<td style="width:119px;">UFC503096</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:276px;">Flexible tubing</td>
			<td style="width:176px;">Saint-Gobain</td>
			<td>B000FOV1J0</td>
			<td>Approximately 1 m length</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:276px;">Ice bucket</td>
			<td style="width:176px;">Any supplier</td>
			<td style="width:119px;">n/a</td>
			<td></td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:276px;">Liquid/air metallic or plastic valve. (e.g. aquarium air/water flow control lever valve)</td>
			<td style="width:176px;">Any supplier&#160;</td>
			<td style="width:119px;">n/a</td>
			<td style="width:249px;">Aquarium valves are compatible.</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:276px;">Mortar and pestle</td>
			<td style="width:176px;">Any supplier</td>
			<td style="width:119px;">n/a</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:276px;">Native PAGE 3-12% T slab gel</td>
			<td style="width:176px;">Invitrogen</td>
			<td>BN1003</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:276px;">Parafilm</td>
			<td style="width:176px;">Bemis</td>
			<td style="width:119px;">PM-996</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:276px;">Petri dish</td>
			<td style="width:176px;">Fisher Scientific</td>
			<td style="width:119px;">08-757-13</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:276px;">Protein low bind tube 1.5 mL</td>
			<td style="width:176px;">Eppendorf</td>
			<td>022431081</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:276px;">Razor blade</td>
			<td style="width:176px;">IDL Tools</td>
			<td style="width:119px;">TE05-091C</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:276px;">Regenerated cellulose dialysis tubing 3,500 MWCO</td>
			<td style="width:176px;">Fisher Scientific</td>
			<td style="width:119px;">21-152-9</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:276px;">SDS-PAGE slab gel for any kDa</td>
			<td style="width:176px;">Bio-Rad</td>
			<td style="width:119px;">456-9036</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:276px;">Serological pipets (25 ml)</td>
			<td style="width:176px;">VWR</td>
			<td style="width:119px;">89130-900</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:276px;">Syringe (10 ml)</td>
			<td style="width:176px;">Any supplier</td>
			<td style="width:119px;">n/a</td>
			<td></td>
		</tr>
	</tbody>
</table>

cn-gelfree - clear native gel-eluted liquid fraction entrapment electrophoresis

Protein complexes perform an array of crucial cellular functions. Elucidating their non-covalent interactions and dynamics is paramount for understanding the role of complexes in biological systems. While the direct characterization of biomolecular assemblies has become increasingly important in recent years, native fractionation techniques that are compatible with downstream analysis techniques, including mass spectrometry, are necessary to further expand these studies. Nevertheless, the field lacks a high-throughput, wide-range, high-recovery separation method for native protein assemblies. Here, we present clear native gel-eluted liquid fraction entrapment electrophoresis (CN-GELFrEE), which is a novel separation modality for non-covalent protein assemblies. CN-GELFrEE separation performance was demonstrated by fractionating complexes extracted from mouse heart. Fractions were collected over 2 hr and displayed discrete bands ranging from ~30 to 500 kDa. A consistent pattern of increasing molecular weight bandwidths was observed, each ranging ~100 kDa. Further, subsequent reanalysis of native fractions via SDS-PAGE showed molecular-weight shifts consistent with the denaturation of protein complexes. Therefore, CN-GELFrEE was proved to offer the ability to perform high-resolution and high-recovery native separations on protein complexes from a large molecular weight range, providing fractions that are compatible with downstream protein analyses.

200 &#181;g of proteins extracted from cryogenically ground mouse hearts were fractionated natively into 14 fractions of 150 &#181;l each, using the CN-GELFrEE method in a 1-12% T gel tube. An aliquot of 10 &#181;l of each fraction was run on a CN-PAGE slab gel and silver stained. A clear depiction of the fractionation and resolution obtained with CN-GELFrEE fractionation is shown in Figure 2A. Fractions were collected over two hours and the gel assay shows a consistent p...

Watch this Scientific Journal Video about CN-GELFrEE - Clear Native Gel-eluted Liquid Fraction Entrapment Electrophoresis at JoVE.com

CN-GELFrEE - Clear Native Gel-eluted Liquid Fraction Entrapment Electrophoresis

This protocol describes how to prepare and perform clear native gel-eluted liquid fraction entrapment electrophoresis (CN-GELFrEE), a native separation technique for non-covalent biomolecular assemblies and proteins from heterogeneous samples that is compatible with various downstream protein analysis techniques.

Protein complexes perform an array of crucial cellular functions. Elucidating their non-covalent interactions and dynamics is paramount for understanding ...

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In situ imaging and elemental analysis of boehmite (AlOOH) particles in water is realized using the System for Analysis at the Liquid Vacuum Interface ...

Liquid-cell Transmission Electron Microscopy for Tracking Self-assembly of Nanoparticles

Drying a nanoparticle dispersion is a versatile way to create self-assembled structures of nanoparticles, but the mechanism of this process is not fully ...

Novel Techniques for Observing Structural Dynamics of Photoresponsive Liquid Crystals

We discuss in this article the experimental measurements of the molecules in liquid crystal (LC) phase using the time-resolved infrared (IR) vibrational ...

Microfluidic Preparation of Liquid Crystalline Elastomer Actuators

This paper focuses on the microfluidic process (and its parameters) to prepare actuating particles from liquid crystalline elastomers. The preparation ...

Large-scale Top-down Proteomics Using Capillary Zone Electrophoresis Tandem Mass Spectrometry

Capillary zone electrophoresis-electrospray ionization-tandem mass spectrometry (CZE-ESI-MS/MS) has been recognized as a useful tool for top-down ...

High-throughput and Comprehensive Drug Surveillance Using Multisegment Injection-Capillary Electrophoresis-Mass Spectrometry

New analytical methods are urgently needed to enable high-throughput, yet comprehensive drug screening, given an alarming opioid and prescription drug ...