Name: synthesis of biocompatible liquid crystal elastomer foams as cell scaffolds for 3d spatial cell cultures
Uploaded: 2017-04-11T15:00:00
Description: Watch this Scientific Journal Video about Synthesis of Biocompatible Liquid Crystal Elastomer Foams as Cell Scaffolds for 3D Spatial Cell Cultures at JoVE.com

The authors would like to thank Kent State University (collaborative research grant and support for the Regenerative Medicine Initiative at Kent State &#8722; ReMedIKS) for the financial support of this project.

NOTE: The following steps for the 3D LCE foam-like preparation using the 3-arm star block copolymer are shown in Figure 1. For nuclear magnetic resonance (NMR) characterization, the spectra are recorded in deuterated chloroform (CDCl3) at room temperature on a Bruker DMX 400-MHz instrument and internally referenced residual peaks at 7.26. Fourier transform infrared (FT-IR) spectra are recorded using a Bruker Vector 33 FT-IR spectrometer using attenuated total reflectance mode. ...

<ol>
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Liquid crystalline elastomers have recently been studied as biocompatible cell scaffolds due to their stimuli responsiveness. They have been proven to be ideal platforms as cell scaffolds. However, an important factor to keep in mind when preparing and designing a new LCE scaffold is porosity. The incorporation of leachable solids23 or gases does not always result in homogeneous porosity or fully interconnected pores. The use of a metal template that can be etched out not only offers the opportuni...

There are several examples of biological and biocompatible synthetic materials designed for application in cell studies and for tissue regeneration aiming at cell attachment and proliferation1,2,3,4,5. There have been a few examples of biocompatible materials, known as liquid crystal elastomers (LCEs), that could respond to external stimuli with anisotropic molecular ordering6,7. LCEs are stimuli-responsive materials that combine the mechanical and elastic properties of elastomers with the optical functionality and molecular ordering of liquid crystals8,9. LCEs can experience changes in shape, mechanical deformation, elastic behavior, and optical properties in response to external stimuli (i.e., heat, stress, light, etc.)10,11,12,13,14,15,16. Earlier studies have shown that liquid crystals (LCs) can sense the growth and orientation of cells4,17. It is possible then to assume that LCEs may be suitable for biologically and medically relevant applications, including cell scaffolding and alignment. We have previously reported the preparation of smectic biocompatible, biodegradable, cast-molded, and thin LCEs films featuring a &#34;Swiss-cheese type&#34; porous morphology6,18. We also prepared nematic biocompatible LCEs with globular morphology as scaffolds for cell growth19,20. Our work was aimed at tuning the mechanical properties of the materials to match those of the tissue of interest21. Also, these studies focus on understanding elastomer-cell interactions, as well as cellular response when the elastomers are subject to external stimuli.
The main challenges were in part to tailor the porosity of the LCEs to allow for cell attachment and permeation through the elastomer matrix and for better mass transport. The porosity of these thin films6 allowed for cell permeation through the bulk of the matrix, but not all pores were fully interconnected or had a more regular (homogeneous) pore size. We then reported on biocompatible nematic LCE elastomers with globular morphologies. These nematic elastomers allowed for the attachment and proliferation of cells, but the pore size ranged only from 10-30 &#181;m, which prevented or limited the use of these elastomers with a wider variety of cell lines19,20.
Previous work by Kung et al. relating to the formation of graphene foams using a &#34;sacrificial&#34; metal template showed that the obtained graphene foam had a very regular porous morphology dictated by the chosen metal template22. This methodology offers full control of porosity and pore size. At the same time, the malleability and flexibility of the metal template allow for the formation of different template shapes prior to foam preparation. Other techniques, such as material leaching23, gas templating24, or electro-spun fibers25,26 also offer the potential for the preparation of porous materials, but they are more time consuming and, in some cases, the pore size is limited to only a few micrometers. Foam-like 3D LCEs prepared using metal templates allow for a higher cell load; an improved proliferation rate; co-culturing; and, last but not least, better mass transport management (i.e., nutrients, gases, and waste) to ensure full tissue development27. Foam-like 3D LCEs also appear to improve cell alignment; this is most likely in relation to the LC pendants sensing cell growth and cell orientation. The presence of LC moieties within the LCE appears to enhance cell alignment with respect to cell location within the LCE scaffold. Cells align within the struts of the LCE, while no clear orientation is observed where the struts join together (junctions)27.
Overall, our LCE cell scaffold platform as a cell support medium offers opportunities to tune the elastomer morphology and elastic properties and to specifically direct the alignment of (individual) cell types to create an ordered, spatial arrangements of cells similar to living systems. Apart from providing a scaffold capable of sustaining and directing long-term cellular growth and proliferation, LCEs also allow for dynamic experiments, where cell orientation and interactions may be modified on the fly.

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	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:291px;">1H, 1H, 2H, 2H-perfluorooctyltriethoxysilane</td>
			<td style="width:148px;">Alfa Aesar</td>
			<td style="width:132px;">L16606</td>
			<td style="width:153px;">Silanizing agent</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">2-bis(4-hydroxy-cyclohexyl)propane</td>
			<td>TCI</td>
			<td><a href="http://www.tcichemicals.com/eshop/en/us/commodity/B0928/">B0928</a></td>
			<td>Reagent</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">2-chlorohexanone&#160;</td>
			<td>Alfa Aesar</td>
			<td>A18613</td>
			<td>Reagent</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">2-heptanone&#160;</td>
			<td>Sigma Aldrich</td>
			<td>W254401</td>
			<td>Solvent</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">2-propanol&#160;</td>
			<td>Sigma Aldrich</td>
			<td>278475</td>
			<td>Solvent</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">3-chloroperbenzoic acid, m-CPBA</td>
			<td>Sigma Aldrich</td>
			<td>273031</td>
			<td>Reagent</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">4-dimethylaminopyridine</td>
			<td>Alfa Aesar</td>
			<td>A13016</td>
			<td>Reagent</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">4&#39;,6-diamidino-2-phenylindole, DAPI&#160;</td>
			<td>Invitrogen</td>
			<td>D1306</td>
			<td>Nuclear Stain</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">5-hexynoic acid&#160;</td>
			<td>Alfa Aesar</td>
			<td>B25132-06</td>
			<td>Reagent</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Acetic acid</td>
			<td>VWR</td>
			<td>36289</td>
			<td>Solvent</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Acetone</td>
			<td>Sigma Aldrich</td>
			<td>34850</td>
			<td>Solvent</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Alcohol 200 proof ACS Grade&#160;</td>
			<td>VWR</td>
			<td>71001-866</td>
			<td>Reagent</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Benzene</td>
			<td>Alfa Aesar</td>
			<td>AA33290</td>
			<td>Solvent</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">&#949;-caprolactone&#160;</td>
			<td>Alfa Aesar</td>
			<td>A10299-0E</td>
			<td>Reagent</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Chloroform</td>
			<td>VWR</td>
			<td>BDH1109</td>
			<td>Solvent</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Cholesterol</td>
			<td>Sigma Aldrich</td>
			<td>C8503</td>
			<td>Reagent</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Chromium(VI) oxide</td>
			<td>Sigma Aldrich</td>
			<td>232653</td>
			<td>Reagent</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Copper (I) iodide</td>
			<td>Strem Chemicals</td>
			<td>100211-060</td>
			<td>Reagent</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">D,L-Lactide&#160;</td>
			<td>Alfa Aesar</td>
			<td>L09026</td>
			<td>Reagent</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Dichloromethane</td>
			<td>Sigma Aldrich</td>
			<td>320269</td>
			<td>Solvent</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Diethyl ether&#160;</td>
			<td>Emd Millipore</td>
			<td>EX0190</td>
			<td>Solvent</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">N,N-Dimethylformamide</td>
			<td>Sigma Aldrich</td>
			<td>270547</td>
			<td>Solvent</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Dulbecco&#8217;s modified Eagle medium, DEME&#160;</td>
			<td>CORNING Cellgo</td>
			<td>10-013</td>
			<td>Cell Media</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Ethanol</td>
			<td>Alfa Aesar</td>
			<td>33361</td>
			<td>Solvent</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Formaldehyde&#160;</td>
			<td>SIGMA Life Science</td>
			<td>F8775</td>
			<td>Fixative</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Fetal bovine serum, FBS&#160;</td>
			<td>HyClone</td>
			<td>SH30071.01</td>
			<td>Media Component</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Filter paper, Grade 415, qualitative, crepe</td>
			<td>VWR</td>
			<td>28320</td>
			<td>Filtration</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Glycerol</td>
			<td>Sigma Aldrich</td>
			<td>G5516</td>
			<td>Central node (3-arm)</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Hexamethylene diisocyanate, HDI</td>
			<td>Sigma Aldrich</td>
			<td>52649</td>
			<td>Crosslinker</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Iron(III) chloride&#160;</td>
			<td>Alfa Aesar</td>
			<td>12357</td>
			<td>Etching agent</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Isopropyl alcohol</td>
			<td>VWR</td>
			<td>BDH1133</td>
			<td>Solvent</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Methanol</td>
			<td>Alfa Aesar</td>
			<td>L13255</td>
			<td>Solvent</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">N,N&#39;-dicyclohexylcarbodiimide</td>
			<td>Aldrich</td>
			<td>D80002</td>
			<td>Solvent</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">N,N-Dimethylformamide</td>
			<td>Sigma Aldrich</td>
			<td>270547</td>
			<td>Solvent</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Nickel metal template</td>
			<td>American Elements</td>
			<td>Ni-860</td>
			<td>Foam template</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Neuroblastomas cells (SH-SY5Y)</td>
			<td>ATCC</td>
			<td>CRL-2266</td>
			<td>Cell line</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Penicillin streptomycin&#160;</td>
			<td>Thermo SCIENTIFIC</td>
			<td>15140122</td>
			<td>Antibiotics</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Polyethylene glycol 2000, PEG</td>
			<td>Alfa Aesar</td>
			<td>B22181</td>
			<td>Reagent</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Sodium azide&#160;</td>
			<td>VWR</td>
			<td>97064-646</td>
			<td>Reagent</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Sodium bicarbonate</td>
			<td>AMRESCO</td>
			<td>865</td>
			<td>Drying salt</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Sodium chloride</td>
			<td>BDH</td>
			<td>BDH9286</td>
			<td>Drying salt</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Sodium phosphate dibasic heptahydrate</td>
			<td>Fisher Scientific</td>
			<td>S-374</td>
			<td>Drying salt</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Sodium phosphate monobasic monohydrate</td>
			<td>Sigma Aldrich</td>
			<td>S9638</td>
			<td>Drying salt</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Sodium sulfate</td>
			<td>Sigma Aldrich</td>
			<td>239313</td>
			<td>Drying salt</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Tetrahydrofuran</td>
			<td>Alfa Aesar</td>
			<td>41819</td>
			<td>Solvent</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Thiosulfate de sodium</td>
			<td>AMRESCO</td>
			<td>393</td>
			<td>Drying salt</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Tin(II) 2-ethylhexanoate</td>
			<td>Aldrich</td>
			<td>S3252</td>
			<td>Reagent</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Toluene&#160;</td>
			<td>Alfa Aesar</td>
			<td>22903</td>
			<td>Solvent</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Triethylamine</td>
			<td>Sigma Aldrich</td>
			<td>471283</td>
			<td>Reagent</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Trypsin&#160;</td>
			<td>HyClone</td>
			<td>SH30042.01</td>
			<td>Cell Detachment</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Olympus FV1000</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
	</tbody>
</table>

synthesis of biocompatible liquid crystal elastomer foams as cell scaffolds for 3d spatial cell cultures

Here, we present a step-by-step preparation of a 3D, biodegradable, foam-like cell scaffold. These scaffolds were prepared by cross-linking star block co-polymers featuring cholesterol units as side-chain pendant groups, resulting in smectic-A (SmA) liquid crystal elastomers (LCEs). Foam-like scaffolds, prepared using metal templates, feature interconnected microchannels, making them suitable as 3D cell culture scaffolds. The combined properties of the regular structure of the metal foam and of the elastomer result in a 3D cell scaffold that promotes not only higher cell proliferation compared to conventional porous templated films, but also better management of mass transport (i.e., nutrients, gases, waste, etc.). The nature of the metal template allows for the easy manipulation of foam shapes (i.e., rolls or films) and for the preparation of scaffolds of different pore sizes for different cell studies while preserving the interconnected porous nature of the template. The etching process does not affect the chemistry of the elastomers, preserving their biocompatible and biodegradable nature. We show that these smectic LCEs, when grown for extensive time periods, enable the study of clinically relevant and complex tissue constructs while promoting the growth and proliferation of cells.

This report shows the preparation method of a porous 3D LCE as a scaffold for cell culture using a nickel metal template. The obtained 3D LCE demonstrates a complex interconnected channel network that allows for easy cell infiltration, as well as more suitable mass transport27. It was found that cells are able to fully penetrate the interconnected channel network and are also able to align within the LCE. Here, a metal nickel foam (99% Ni, density of 860 g/cm2...

Watch this Scientific Journal Video about Synthesis of Biocompatible Liquid Crystal Elastomer Foams as Cell Scaffolds for 3D Spatial Cell Cultures at JoVE.com

Synthesis of Biocompatible Liquid Crystal Elastomer Foams as Cell Scaffolds for 3D Spatial Cell Cultures

This study presents a methodology to prepare 3D, biodegradable, foam-like cell scaffolds based on biocompatible side-chain liquid crystal elastomers (LCEs). Confocal microscopy experiments show that foam-like LCEs allow for cell attachment, proliferation, and the spontaneous alignment of C2C12s myoblasts.

Here, we present a step-by-step preparation of a 3D, biodegradable, foam-like cell scaffold. These scaffolds were prepared by cross-linking star block ...

The goal of this procedure is to prepare biodegradable, three dimensional foam-like cell scaffolds based on biocompatible side chain liquid crystal elastomers. This method can help answer key questions in the liquid crystal and biomedical fields, such as the effects of liquid crystal elastomer properties on cell proliferation and alignment. The main advantage of this method of two dimensional cell scaffolds is it permits the study of spatial cell-cell interactions which is rarely possible in 2D macro environments.Generally, those new to this method will struggle with the tactile compression tests. We first had the idea for this method after having to change the media in hundreds of Petri dishes. We wondered if liquid crystal elastomers could support muscle cells on a 3D network, to eliminate the use of so many Petri dishes.Visual demonstration of this method is critical, as some steps require careful manipulation of chemicals. Further, shaping the metal foam template may be challenging. First, fill a 20 milliliter ampoule with a 2%by volume solution of PFOTES in toluene.Stir the solution in the ampoule for 24 hours to silanize the ampoule interior. Rinse the silanized ampoule with isopropyl alcohol and dry it at 140 degrees celsius for 30 minutes. Place 3.64 grams of distilled epsilon-caprolactone, 0.5 grams of alpha-chloro-epsilon-caprolactone, and 0.25 milliliters of glycerol in the dry ampoule.Vortex the mixture for one minute. Then, add 4.90 grams of DL-lactide to the mixture, and purge the ampoule atmosphere with nitrogen gas for one minute. Cover the ampoule opening with aluminum foil, and heat the mixture at 120 degrees Celsius for about two hours to melt the DL-lactide.Vortex the mixture to disrupt any unmelted solids, and then, add 66 microliters of 10-2-ethylhexanoate to the ampoule, and vortex again. Close the ampoule with aluminum foil and heat the mixture at 120 degrees Celsius for 10 minutes to remelt the DL-lactide. Once the DL-lactide has melted again, vigorously vortex the mixture, and purge the ampoule atmosphere with nitrogen gas.Seal the ampoule with a rubber septum. Insert a needle connected to a vacuum line through the septum, and start the vacuum. Flame-seal the neck of the ampoule, being careful not to melt the rubber stopper.Once the neck is sealed, heat the reaction mixture at 140 degrees Celsius for 48 hours. Then, allow the mixture to cool to room temperature. Break open the ampoule and dissolve the viscous reaction mixture in 10 milliliters of dichloromethane.Transfer the mixture to a separatory funnel. Place a flask containing 100 milliliters of methanol in a dry ice and acetone bath to cool down the methanol to approximately minus 78 degrees Celsius. Once the methanol has cooled down, secure the separatory funnel over the flask.Add the reaction mixture to the cold methanol at a rate of two drops every second. Collect the resulting white precipitate on filter paper. Dry the precipitate in a vacuum oven between 50 and 60 degrees Celsius to obtain the three-arm alpha-chloro SBC product.To prepare the alpha cholesteryl three-arm SBC, the pendant chlorine atom is replaced by an azide. A click reaction with cholesteryl 5-hexynoate results in a pendant cholesteryl as the liquid crystal moiety. To begin preparing the liquid crystal elastomer scaffold, combine 0.75 grams of alpha-cholesteryl three-arm SBC with 0.25 milliliters of HDI and 0.24 milliliters of distilled epsilon-caprolactone.Add to this 60 microliters of 10-2-ethylhexanoate and vortex the mixture. Then, cut out a one centimeter by four centimeter piece of nickel metal foam. Roll the nickel foam into a cylinder one centimeter in diameter and one centimeter tall to form a template for the liquid crystal elastomer foam scaffold.Place the template in a glass vial or aluminum foil enclosure, and pour the liquid crystal elastomer mixture over the template until it is completely covered. Allow the template to sit in the liquid crystal elastomer mixture for two minutes, and then, remove the excess with a pipette. Heat the mixture and template at 80 degrees Celsius overnight.Then, peel away the aluminum foil, or break the glass. Use a razor blade to remove excess liquid crystal elastomer to expose the nickel metal template. Place the foam in a flask and add 70 milliliters of a saturated aqueous solution of iron three chloride.Stir the foam in the solution for three days at room temperature to dissolve the nickel template. Every 24 hours, stir the foam in deionized water for 30 minutes, and then, resume stirring in a fresh iron three chloride solution. After the second day of stirring, perform a tactile compression test on the liquid crystal elastomer foam.Resistance to tactile compression indicates that the nickel template is still present in the foam. After the third day, all nickel template has been eliminated, and the resulting foam appears very soft and easy to fully compress. The nickel template must be completely eliminated.It is important to thoroughly rinse the liquid crystal elastomer foam in iron chloride until it's soft to the touch when a tactile compression test is performed. The liquid crystal elastomer foam scaffold is now ready to be characterized and used. Once the liquid crystal elastomer foam is soft, rinse it with 70%ethanol to sterilize it.To begin the seeding procedure, wash again the liquid crystal elastomer foam scaffolds twice in one milliliter of 70%ethanol to sterilize the elastomer surfaces. Then, irradiate the scaffolds with UV light for 10 minutes. Wash the scaffolds with another one milliliter portion of 70%ethanol.Rinse the scaffolds with one milliliter each of sterile water and phosphate-buffered saline. Load the sterilized liquid crystal elastomer scaffolds into 24-well culture plates. Prepare and count a suspension of the cells of interest in the appropriate cell growth medium with penicillin and streptomycin.Dilute the cell suspension to 1.5 times 10 to the fifth cells per 100 microliters using growth medium. Deposit a drop of diluted cell suspension on top of each liquid crystal elastomer scaffold. Incubate the seeded liquid crystal elastomer scaffolds at 37 degrees Celsius in a 5%CO2 atmosphere for two hours.Add another 0.5 milliliters of growth medium to each scaffold, and continue incubation. Every 48 hours, wash the seeded scaffolds with one milliliter of PBS, and add fresh growth medium. Continue incubating the scaffolds until the cells are ready for microscopy.These smetic LCs enable the study of complex tissue constructs while promoting cell growth and proliferation. In order to maintain cell viability, foams must be sterilized and cleanliness of cultures maintained at all times. To prepare for microscopy, fix the cells on the scaffolds with a solution of 4%paraformaldehyde in PBS for 15 minutes.Soak the samples three times in three milliliters of PBS for five minutes. Place one scaffold sample in an Eppendorf tube. Stain the sample with a solution of 0.1%DAPI in 500 microliters of PBS for 10 minutes.Soak the sample twice in one milliliter of PBS for five minutes. And then, immediately image the sample with confocal microscopy. Acquire image stacks spanning the sample and analyze the data in an image processing program.A three-arm SBC with liquid crystal moieties was cast on a nickel foam template with HDI as the cross-linker. The nickel template was removed by etching to obtain the liquid crystal elastomer foam. Compression deformation testing was periodically performed to monitor the etching process.Once the nickel had been completely dissolved, the compression deformation testing showed a 70%reduction in size when compressed. Upon releasing compression, the liquid crystal elastomer foam consistently recovered its original size and shape. This behavior is attributed to the liquid crystal moieties, as similar elastomer foams lacking the cholesterol epsilon-caprolactone moiety did not recover from compression.SCM of the internal foam morphology showed an interconnected network of hollow foam struts. The regular morphology was attributed to the structure of the nickel foam, indicating that pore size and overall shape can be controlled by selection of an appropriate metal template. The foam was seeded with neuroblastoma cells, which attached to the walls of the network within two days.30 days after seeding, confocal microscopy revealed that the cells extended over the liquid crystal elastomer network, and had formed multiple layers dispersed throughout the elastomer foam. Elongation of cell nuclei was observed, and was correlated to cell alignment. Once mastered, this technique can be done within three to four weeks if performed properly.After watching this video, you should have a good understanding of how to design and prepare liquid crystal elastomer cell scaffolds with specific pore sizes and morphologies. While attempting this procedure, it's important to fully characterize each product and to monitor cell viability and expansion. Further, proper staining technique is important to easily acquire confocal microscopy images.Following this procedure, liquid crystal elastomers can also be exposed to external stimuli, such as stress, or magnetic and electric fields, to answer additional questions about how the anisotropic molecular ordering of the liquid crystal elastomers affects cell response. The implications of this technique apply to the study of disease processes, as it provides a platform to dynamically study the effects of external agents on simulated disease activity, and subsequent repair processes. Though this smectic liquid crystal elastomer foam can provide insight into cell-cell interactions, they can also be used with other materials, such as semiconductor or metal nanostructures.After its development, this technique paved the way for researchers in biomedical fields to design long-term experimental platforms mirroring living systems.

Research

JoVE Journal

Bioengineering

Alginate Microcapsule as a 3D Platform for Propagation and Differentiation of Human Embryonic Stem Cells (hESC) to Different Lineages

Alginate Microcapsule as a 3D Platform for Propagation and Differentiation of Human Embryonic Stem Cells hESC to Different Lineages

Human embryonic stem cells (hESC) are emerging as an attractive alternative source for cell replacement therapy since they can be expanded in culture ...

Preparation of 3D Fibrin Scaffolds for Stem Cell Culture Applications

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Self-reporting Scaffolds for 3-Dimensional Cell Culture

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Fabrication of Mechanically Tunable and Bioactive Metal Scaffolds for Biomedical Applications

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Alternating Magnetic Field-Responsive Hybrid Gelatin Microgels for Controlled Drug Release

Magnetically-responsive nano/micro-engineered biomaterials that enable a tightly controlled, on-demand drug delivery have been developed as new types of ...

Preparation of Monodomain Liquid Crystal Elastomers and Liquid Crystal Elastomer Nanocomposites

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Micropatterning and Assembly of 3D Microvessels

In vitro platforms to study endothelial cells and vascular biology are largely limited to 2D endothelial cell culture, flow chambers with polymer or glass ...

Fabrication of Extracellular Matrix-derived Foams and Microcarriers as Tissue-specific Cell Culture and Delivery Platforms

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A Microcontroller Operated Device for the Generation of Liquid Extracts from Conventional Cigarette Smoke and Electronic Cigarette Aerosol

Electronic cigarettes are the most popular tobacco product among middle and high schoolers and are the most popular alternative tobacco product among ...

3D Analysis of Multi-cellular Responses to Chemoattractant Gradients

Various limitations of 2D cell culture systems have sparked interest in 3D cell culture and analysis platforms, which would better mimic the spatial and ...