Name: production of near-infrared sensitive, core-shell vaccine delivery platform
Uploaded: 2020-10-20T12:30:00
Description: Watch this Scientific Journal Video about Production of Near-Infrared Sensitive, Core-Shell Vaccine Delivery Platform at JoVE.com

We would like to thank Dr. Bryan E. Tomlin affiliated with the elemental analysis lab within the department of chemistry at TAMU who assisted with the neutron activation analysis (NAA).

1. Polycaprolacyone triacrylate (PCLTA) synthesis
<ol>
	<li>Dry 3.2 mL of 400 Da polycaprolacyone (PCL) triol overnight at 50 &#176;C in an open 200 mL round bottom flask and K2CO3 in a glass vial at 90 &#176;C.</li>
	<li>Mix the triol with 6.4 mL of dichloromethane (DCM) and 4.246 g of potassium carbonate (K2CO3) under argon.</li>
	<li>Mix 2.72 mL of acryloyl chloride in 27.2 mL of DCM and add dropwise to the reaction mixture in the flask over 5 min.</li>
	<li>Cover the reac...

<ol>
	<li>. Global Immunization: Worldwide Disease Incidence Available from: <a target="_blank" href="https://www.chop.edu/centers-programs/vaccine-education-center/global-immunization/diseases-and-vaccines-world-view">https://www.chop.edu/centers-programs/vaccine-education-center/global-immunization/diseases-and-vaccines-world-view</a> (2018)</li><li>Paul, A., Bera, M., Gupta, P., Singh, N. D. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=o-Hydroxycinnamate+for+sequential+photouncaging+of+two+different+functional+groups+and+its+application+in+releasing+cosmeceuticals.">o-Hydroxycinnamate for sequential photouncaging of two different functional groups and its application in releasing cosmeceuticals.</a> Organic and Biomolecular Chemistry. 17 (33), 7689-7693 (2019).</li><li>Kumari, A., Yadav, S. K., Yadav, S. 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+polymeric+nanoparticles+based+drug+delivery+systems.">Biodegradable polymeric nanoparticles based drug delivery systems.</a> Colloids and Surfaces B: Biointerfaces. 75 (1), 1-18 (2010).</li><li>Dai, C., Wang, B., Zhao, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Microencapsulation+peptide+and+protein+drugs+delivery+system.">Microencapsulation peptide and protein drugs delivery system.</a> Colloids and Surfaces B: Biointerfaces. 41 (2-3), 117-120 (2005).</li><li>Souery, W. N., 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=Controlling+and+quantifying+the+stability+of+amino+acid-based+cargo+within+polymeric+delivery+systems.">Controlling and quantifying the stability of amino acid-based cargo within polymeric delivery systems.</a> Journal of Control Release. 300, 102-113 (2019).</li><li>Wang, W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Advanced+protein+formulations.">Advanced protein formulations.</a> Protein Science. 24 (7), 1031-1039 (2015).</li><li>Lee, J., 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=An+ultraviolet-curable,+core-shell+vaccine+formed+via+phase+separation.">An ultraviolet-curable, core-shell vaccine formed via phase separation.</a> Journal of Biomedical Materials Research Part A. , (2019).</li><li>Kittler, S., Hickey, S. G., Wolff, T., Eychm&#252;ller, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Easy+and+Fast+Phase+Transfer+of+CTAB+Stabilised+Gold+Nanoparticles+from+Water+to+Organic+Phase.">Easy and Fast Phase Transfer of CTAB Stabilised Gold Nanoparticles from Water to Organic Phase.</a> Zeitschrift f&#252;r Physikalische Chemie. 229, 235 (2015).</li><li>Soliman, M. G., Pelaz, B., Parak, W. J., del Pino, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Phase+Transfer+and+Polymer+Coating+Methods+toward+Improving+the+Stability+of+Metallic+Nanoparticles+for+Biological+Applications.">Phase Transfer and Polymer Coating Methods toward Improving the Stability of Metallic Nanoparticles for Biological Applications.</a> Chemistry of Materials. 27 (3), 990-997 (2015).</li><li>Arun Kumar, S., Good, J., Hendrix, D., Yoo, E., Kim, D., Deo, K. A., Jhan, Y. Y., Gaharwar, A. K., Bishop, C. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Nanoengineered+Light-Activatable+Polybubbles+for+On?Demand+Therapeutic+Delivery.">Nanoengineered Light-Activatable Polybubbles for On?Demand Therapeutic Delivery.</a> Adv. Funct. Mater. , 2003579 (2020).</li><li>Wuthrich, P., Ng, S. Y., Fritzinger, B. K., Roskos, K. V., Heller, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Pulsatile+and+delayed+release+of+lysozyme+from+ointment-like+poly(ortho+esters).">Pulsatile and delayed release of lysozyme from ointment-like poly(ortho esters).</a> Journal of Controlled Release. 21 (1), 191-200 (1992).</li><li>Wang, W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Instability,+stabilization,+and+formulation+of+liquid+protein+pharmaceuticals.">Instability, stabilization, and formulation of liquid protein pharmaceuticals.</a> International Journal of Pharmaceutics. 185 (2), 129-188 (1999).</li><li>Wong, D. Y., Hollister, S. J., Krebsbach, P. H., Nosrat, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Poly(epsilon-caprolactone)+and+poly+(L-lactic-co-glycolic+acid)+degradable+polymer+sponges+attenuate+astrocyte+response+and+lesion+growth+in+acute+traumatic+brain+injury.">Poly(epsilon-caprolactone) and poly (L-lactic-co-glycolic acid) degradable polymer sponges attenuate astrocyte response and lesion growth in acute traumatic brain injury.</a> Tissue Engineering. 13 (10), 2515-2523 (2007).</li><li>Davoodi, P., 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=Drug+delivery+systems+for+programmed+and+on-demand+release.">Drug delivery systems for programmed and on-demand release.</a> Advanced Drug Delivery Reviews. 132, 104-138 (2018).</li><li>Huang, Y. C., Lei, K. F., Liaw, J. W., Tsai, S. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+influence+of+laser+intensity+activated+plasmonic+gold+nanoparticle-generated+photothermal+effects+on+cellular+morphology+and+viability:+a+real-time,+long-term+tracking+and+monitoring+system.">The influence of laser intensity activated plasmonic gold nanoparticle-generated photothermal effects on cellular morphology and viability: a real-time, long-term tracking and monitoring system.</a> Photochemical and Photobiological Sciences. 18 (6), 1419-1429 (2019).</li><li>Link, S., Burda, C., Nikoobakht, B., El-Sayed, M. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Laser-Induced+Shape+Changes+of+Colloidal+Gold+Nanorods+Using+Femtosecond+and+Nanosecond+Laser+Pulses.">Laser-Induced Shape Changes of Colloidal Gold Nanorods Using Femtosecond and Nanosecond Laser Pulses.</a> The Journal of Physical Chemistry B. 104 (26), 6152-6163 (2000).</li><li>. Chlorine Available from: <a target="_blank" href="https://www.epa.gov/sites/production/files/2016-09/documents/chlorine.pdf">https://www.epa.gov/sites/production/files/2016-09/documents/chlorine.pdf</a> (2000)</li></ol>

Current technologies and challenges 
Emulsion-based micro- and nanoparticles have been commonly used as drug delivery carriers. Although release kinetics of the cargo from these devices have been extensively studied, controlling burst release kinetics has been a major challenge11. Cargo versatility and functionality is also limited in emulsion-based systems owing to the exposure of cargo to excess aqueous and organic solvents. Protein-based cargo are often not compatible with...

Limited immunization coverage results in the death of 3 million people specifically caused by vaccine-preventable diseases1. Inadequate storage and transportation conditions lead to wastage of functional vaccines and thus contribute to reduced global immunization. In addition, incomplete vaccination due to not adhering to the required vaccine schedules also causes limited vaccine coverage, specifically in developing countries2. Multiple visits to medical personnel are required within the recommended period for receiving booster shots, thus limiting the percentage of population with complete vaccination. Hence, there is a need for developing novel strategies for controlled vaccine delivery to circumvent these challenges.
Current efforts towards developing vaccine delivery technologies include emulsion-based polymeric systems3,4. However, cargo is often exposed to greater quantity of organic solvent that can potentially cause aggregation and denaturation, specifically in the context of protein-based cargo5,6. We have developed a novel vaccine delivery platform, &#34;polybubbles&#34;, that can potentially house multiple cargo compartments while minimizing the volume of cargo that is exposed to solvent7. For example, in our polybubble core-shell platform, one cargo pocket of diameter 0.38 mm (SEM) is injected in the center of a 1 mm polybubble. In this case, surface area of cargo exposed to organic solvent would be approximately 0.453 mm2. After considering the packing density of spheres (microparticles) within a sphere (cargo depot), the actual volume of microparticles (10 &#181;m in diameter) that could fit in the depot is 0.17 mm3. The volume of one microparticle is 5.24x10-8 mm3 and thus number of particles microparticles that can fit the depot is ~3.2x106 particles. If each microparticle has 20 cargo pockets (as a result of double-emulsion) of 0.25 &#181;m diameter, then the surface area of cargo exposed to organic solvent is 1274 mm2. Cargo depot within the polybubble thus would have ~2800-fold less surface area exposed to organic solvent compared to that of organic solvent-exposed cargo in microparticles. Our polyester-based platform can thus potentially reduce the quantity of cargo exposed to organic solvent which can otherwise cause cargo aggregation and instability.
Polybubbles are formed based on phase-separation principle where the polyester in organic phase is injected into an aqueous solution resulting in a spherical bubble. Cargo in the aqueous phase can then be injected in the center of the polybubble. Another cargo compartment can potentially be achieved within the polybubble by mixing a different cargo with the polymer shell. The polybubble at this stage will be malleable and will then be cured to result in a solid polybubble structure with cargo in the middle. Spherical polybubbles were chosen over other geometrical shapes to increase the cargo capacity within the polybubble while minimizing the overall size of the polybubble. Polybubbles with cargo in the center were chosen to demonstrate delayed burst release. Polybubbles were also incorporated with near infrared (NIR)- sensitive (i.e., theranostic-enabling) agent, namely gold nanorods (AuNR), to cause increase in temperature of the polybubbles. This effect could potentially facilitate faster degradation and could be used for controlling kinetics in future applications. In this paper, we describe our approach to form and characterize polybubbles, to achieve delayed burst release from the polybubbles, and to incorporate AuNR within the polybubbles to cause NIR-activation.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>1-Step Ultra Tetramethylbezidine (TMB)-Enzyme-Linked Immunosorbent Assay (ELISA) Substrate Solution</td>
			<td>Thermo scientific</td>
			<td>34028</td>
			<td></td>
		</tr>
		<tr>
			<td>2-Hydroxy-2-methylpropiophenone</td>
			<td>TCI AMERICA</td>
			<td>H0991</td>
			<td></td>
		</tr>
		<tr>
			<td>450 nm Stop Solution for TMB Substrate</td>
			<td>Abcam</td>
			<td>ab17152</td>
			<td></td>
		</tr>
		<tr>
			<td>Acryloyl chloride</td>
			<td>Sigma Aldrich</td>
			<td>A24109-100G</td>
			<td></td>
		</tr>
		<tr>
			<td>Acriflavine</td>
			<td>Chem-Impex International</td>
			<td>22916</td>
			<td></td>
		</tr>
		<tr>
			<td>Anhydrous ethyl ether</td>
			<td>Fisher Chemical</td>
			<td>E138-500</td>
			<td></td>
		</tr>
		<tr>
			<td>Anti-HIV1 gp120 antibody conjugated to horseradish peroxidase (HRP)</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Bovine serum albumin (BSA)</td>
			<td>Fisher BioReagents</td>
			<td>BP9700100</td>
			<td></td>
		</tr>
		<tr>
			<td>BSA-CF488 dye conjugates</td>
			<td>Invitrogen</td>
			<td>A13100</td>
			<td></td>
		</tr>
		<tr>
			<td>Bromosalicylic acid</td>
			<td>Acros Organics</td>
			<td>AC162142500</td>
			<td></td>
		</tr>
		<tr>
			<td>Carboxymethylcellulose (CMC)</td>
			<td>Millipore Sigma</td>
			<td>80502-040</td>
			<td></td>
		</tr>
		<tr>
			<td>Centrimonium bromide (CTAB)</td>
			<td>MP Biomedicals</td>
			<td>ICN19400480</td>
			<td></td>
		</tr>
		<tr>
			<td>Chloroform</td>
			<td>Fisher Chemical</td>
			<td>C2984</td>
			<td></td>
		</tr>
		<tr>
			<td>Coating buffer</td>
			<td>Abcam</td>
			<td>ab210899</td>
			<td></td>
		</tr>
		<tr>
			<td>Dichloromethane (DCM)</td>
			<td>Sigma Aldrich</td>
			<td>270997-1L</td>
			<td></td>
		</tr>
		<tr>
			<td>Diethyl ether</td>
			<td>Fisher Chemical</td>
			<td>E1384</td>
			<td></td>
		</tr>
		<tr>
			<td>Dodeacyl Amine</td>
			<td>Acros Organics</td>
			<td>AC117665000</td>
			<td></td>
		</tr>
		<tr>
			<td>Doxorubicin hydrochloride</td>
			<td>Fisher BioReagents</td>
			<td>BP251610</td>
			<td></td>
		</tr>
		<tr>
			<td>L-ascorbic acid</td>
			<td>Acros Organics</td>
			<td>A61 100</td>
			<td></td>
		</tr>
		<tr>
			<td>Legato 100 Syringe Pump</td>
			<td>KD Scientific</td>
			<td>14 831 212</td>
			<td></td>
		</tr>
		<tr>
			<td>mPEG thiol</td>
			<td>Laysan Bio</td>
			<td>NC0702454</td>
			<td></td>
		</tr>
		<tr>
			<td>Nonfat dry milk</td>
			<td>Andwin Scientific</td>
			<td>NC9022655</td>
			<td></td>
		</tr>
		<tr>
			<td>Potassium carbonate</td>
			<td>Acros Organics</td>
			<td>AC424081000</td>
			<td></td>
		</tr>
		<tr>
			<td>Phosphate saline buffer</td>
			<td>Fisher BioReagents</td>
			<td>BP3991</td>
			<td></td>
		</tr>
		<tr>
			<td>(Poly(caprolactone)</td>
			<td>Sigma Aldrich</td>
			<td>440744-250G</td>
			<td></td>
		</tr>
		<tr>
			<td>(Poly(caprolactone) triol</td>
			<td>Acros Organics</td>
			<td>AC190730250</td>
			<td></td>
		</tr>
		<tr>
			<td>Poly (lactic-co-glycolic acid) diacrylate</td>
			<td>CMTec</td>
			<td>280050</td>
			<td></td>
		</tr>
		<tr>
			<td>Potassium carbonate</td>
			<td>Acros Organics</td>
			<td>AC424081000</td>
			<td></td>
		</tr>
		<tr>
			<td>Recombinant HIV1 gp120 + gp41 protein</td>
			<td>Abcam</td>
			<td>ab49054</td>
			<td></td>
		</tr>
		<tr>
			<td>Silver nitrate</td>
			<td>Acros Organics</td>
			<td>S181 25</td>
			<td></td>
		</tr>
		<tr>
			<td>Sodium borohydride</td>
			<td>Fisher Chemical</td>
			<td>S678 10</td>
			<td></td>
		</tr>
		<tr>
			<td>Tetrachloroauric acid</td>
			<td>Fisher Chemical</td>
			<td>G54 1</td>
			<td></td>
		</tr>
		<tr>
			<td>Trehalose</td>
			<td>Acros Organics</td>
			<td>NC9022655</td>
			<td></td>
		</tr>
		<tr>
			<td>Triethyl amine</td>
			<td>Acros Organics</td>
			<td>AC157910010</td>
			<td></td>
		</tr>
	</tbody>
</table>

production of near-infrared sensitive, core-shell vaccine delivery platform

Vaccine delivery strategies that can limit the exposure of cargo to organic solvent while enabling novel release profiles are crucial for improving immunization coverage worldwide. Here, a novel injectable, ultraviolet- curable and delayed burst release- enabling vaccine delivery platform called polybubbles is introduced. Cargo was injected into polyester-based polybubbles that were formed in 10% carboxymethycellulose -based aqueous solution. This paper includes protocols to maintain spherical shape of the polybubbles and optimize cargo placement and retention to maximize the amount of cargo within the polybubbles. To ensure safety, chlorinated solvent content within the polybubbles were analyzed using neutron activation analysis. Release studies were conducted with small molecules as cargo within the polybubble to confirm delayed burst release. To further show the potential for on-demand delivery of the cargo, gold nanorods were mixed within the polymer shell to enable near-infrared laser activation.

Polybubbles were extensively characterized using SEM and NAA. Cargo was successfully centered to result in a delayed burst release. Polybubbles were also successfully laser-activated because of the presence of AuNRs within the polybubbles.
Polybubble characterization 
Polybubbles injected in an aqueous solution without CMC resulted in a flattened polybubble due to their contact with the bottom of the glass ...

Watch this Scientific Journal Video about Production of Near-Infrared Sensitive, Core-Shell Vaccine Delivery Platform at JoVE.com

Production of Near-Infrared Sensitive, Core-Shell Vaccine Delivery Platform

This article describes the protocols used to produce a novel vaccine delivery platform, &#34;polybubbles,&#34; to enable delayed burst release. Polyesters including poly(lactic-co-glycolic acid) and polycaprolactone were used to form the polybubbles and small molecules and antigen were used as cargo.

Vaccine delivery strategies that can limit the exposure of cargo to organic solvent while enabling novel release profiles are crucial for improving ...

This protocol can help maintain the cargo stability, which can be both small molecules and proteins, through the use of the polybubble, which can in turn reduce the carbon interactions with the solvent. This novel technique can be used to improve vaccine coverage in the developing countries as vaccine functionalities can often be compromised due to inefficient transportation and storage facilities. To fabricate the polybubbles, first use a one milliliter transfer pipette to add 800 microliters of 10%CMC into a 0.92 milliliter glass vial.To synthesize PCLTA, mix 1, 000 grams per milliliter of 14 kilodalton PCL in 200 microliters of DCM. To synthesize PLGADA, mix 1, 000 grams per milliliter of five kilodalton PLGADA into 200 microliters of chloroform. Mix photoinitiator with the polymer mixture of interest at a 0.005 to 1 ratio and load 200 microliters of the resulting solution into a one milliliter glass syringe mounted on a syringe pump connected to a dispensing stainless steel tube with an inner diameter of 0.016 inch.Using a micro motor to control the forward and backward motion of the polymer tube, inject the polymer into the 10%CMC in the glass vial to form the polybubbles and cure the polybubbles under ultraviolet light at a 254 nanometer wavelength for 60 seconds at two watts per square centimeter, then flash freeze the polybubbles in liquid nitrogen for 30 seconds and lyophilize the carriers overnight at 0.01 millibar vacuum in minus 85 degrees Celsius. For centering of the cargo of interest within a polybubble, mix the cargo with 5%CMC in a rotator overnight to increase the viscosity of the cargo before manually injecting two microliters of the cargo mixture into the polybubble. When all of the cargo has been injected, re-cure, flash freeze, and lyophilize the injected polybubble as just demonstrated.The next morning, use forceps to separate the polybubble from the dried CMC and wash the polybubble with deionized water to remove any residual CMC. Then cut the polybubble in half and image the halves by confocal microscopy to ensure that the cargo is centered. For small molecule cargo release, incubate the polybubbles with centered acriflavine in 400 microliters of PBS at 37 degrees Celsius for the appropriate incubation length.At each experimental time point, collect the supernatant and add 400 microliters of fresh PBS to the vial. Then use a plate reader to quantify the fluorescence intensity of the collected supernatant. For near-infrared activation, mix the polymer solution with hydrophobicized gold nano rods at a one to nine ratio and add photo initiator at a 0.005 to 1 ratio.Inject the resulting mixture into a 0.92 milliliter glass vial containing 800 microliters of 10%CMC and cure the polybubbles under ultraviolet light as demonstrated. After flash freezing and lyophilization as demonstrated, wash the polybubbles with deionized water and incubate the carriers in 400 microliters of PBS at 37 degrees Celsius for the appropriate incubation period. At the end of the incubation, obtain a forward looking infrared image of the polybubble before and after activating the polybubbles with an 801 nanometer near-infrared laser at eight amps for five minutes three times a week for four weeks for PLGADA polybubbles and 14 weeks for PCL-PCLTA polybubbles.At each experimental time point, collect the supernatant and add 400 microliters of fresh PBS to the vial. Then calculate the temperature differences between the polybubbles before and after laser activation based on the temperature values from the forward looking infrared images. The addition of 10%CMC-based aqueous solution results in a complete polybubble suspension for a successful maintenance of the polybubble sphericity.Cargo injection into the polybubble in the absence of CMC results in leakage and a consequent lack of cargo retention within the polybubble. To address this leakage, the viscosity of the PCLTA can be increased using potassium carbonate isolated after end capping polycaprolactone with triacrylate and the viscosity of the cargo can be increased by mixing the cargo with 5%CMC. The viscosity of the PLGADA polybubbles is sufficient to facilitate centering of the cargo and does not require modulation via potassium carbonate.Note that no statistically significant difference in the binding efficiency of the antibody is observed after mixing HIV gp120/41 antigen with and without trehalose before polybubble injection. Delayed burst releases are observed in PLGADA polybubbles with acriflavine in the middle on day 19 for polybubbles incubated at 37 degrees Celsius and on day five for polybubbles incubated at 50 degrees Celsius. In addition, PLGADA polybubbles and PCL and PCLTA polybubbles containing gold nano rods can be successfully laser-activated multiple times.When forming the polybubbles, please take care to protect the reagents from the light and also to use the solutions immediately. After developing this technology, we also wanted to explore automating this process to the scale up the polybubble production.

Research

JoVE Journal

Biology

Technical Demonstration of Whole Genome Array Comparative Genomic Hybridization

Array comparative genomic hybridization (array CGH) is a method for detecting gains and losses of DNA segments or gene dosage in the genome 1.  Recent ...

Exploring Cognitive Functions in Babies, Children &amp; Adults with Near Infrared Spectroscopy

Exploring Cognitive Functions in Babies, Children & Adults with Near Infrared Spectroscopy

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A Convenient and General Expression Platform for the Production of Secreted Proteins from Human Cells

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The MultiBac Protein Complex Production Platform at the EMBL

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A Strategy for Sensitive, Large Scale Quantitative Metabolomics

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Phosphopeptide Analysis of Rodent Epididymal Spermatozoa

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gDNA Enrichment by a Transposase-based Technology for NGS Analysis of the Whole Sequence of BRCA1, BRCA2, and 9 Genes Involved in DNA Damage Repair

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Method for the Assessment of Effects of a Range of Wavelengths and Intensities of Red/near-infrared Light Therapy on Oxidative Stress In Vitro

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Red/near-infrared light therapy (R/NIR-LT), delivered by laser or light emitting diode (LED), improves functional and morphological outcomes in a range of ...

Near Infrared (NIr) Light Increases Expression of a Marker of Mitochondrial Function in the Mouse Vestibular Sensory Epithelium

Near Infrared NIr Light Increases Expression of a Marker of Mitochondrial Function in the Mouse Vestibular Sensory Epithelium

Strategies for attenuating decline in balance function with increasing age are predominantly focused on physical therapies including balance tasks and ...

Enrichment of Extracellular Matrix Proteins from Tissues and Digestion into Peptides for Mass Spectrometry Analysis

The extracellular matrix (ECM) is a complex meshwork of cross-linked proteins that provides biophysical and biochemical cues that are major regulators of ...