Name: development of an in vitro ocular platform to test contact lenses
Uploaded: 2016-04-06T15:00:00
Description: Watch this Scientific Journal Video about Development of an In Vitro Ocular Platform to Test Contact Lenses at JoVE.com

The authors would like to acknowledge our funding source NSERC 20/20 Network for the Development of Advanced Ophthalmic Materials.

All experiments were completed in accordance and compliance with all relevant guidelines outlined by the University of Waterloo&#39;s animal research ethics committee. The bovine eyes are generously donated from a local abattoir.
1. Eye Model
<ol>
	<li>Design and Production of Molds13
	<ol>
		<li>Design the eye models according to the average physiological dimensions of human adult eyes.13</li>
		<li>Leave a gap of 250 &#181;m between the eyeball and the eyelid pieces of the eye model. Desi...

<ol>
	<li>Phan, C. M., Subbaraman, L. N., Jones, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+vitro+drug+release+of+natamycin+from+beta-cyclodextrin+and+2-hydroxypropyl-beta-cyclodextrin-functionalized+contact+lens+materials.">In vitro drug release of natamycin from beta-cyclodextrin and 2-hydroxypropyl-beta-cyclodextrin-functionalized contact lens materials.</a> J Biomater Sci Polym Ed. 25, 1907-1919 (2014).</li><li>Peng, C. C., Kim, J., Chauhan, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Extended+delivery+of+hydrophilic+drugs+from+silicone-hydrogel+contact+lenses+containing+vitamin+E+diffusion+barriers.">Extended delivery of hydrophilic drugs from silicone-hydrogel contact lenses containing vitamin E diffusion barriers.</a> Biomaterials. 31, 4032-4047 (2010).</li><li>Hui, A., Willcox, M., Jones, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+vitro+and+in+vivo+evaluation+of+novel+ciprofloxacin-releasing+silicone+hydrogel+contact+lenses.">In vitro and in vivo evaluation of novel ciprofloxacin-releasing silicone hydrogel contact lenses.</a> Invest Ophthalmol Vis Sci. 55, 4896-4904 (2014).</li><li>Boone, A., Hui, A., Jones, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Uptake+and+release+of+dexamethasone+phosphate+from+silicone+hydrogel+and+group+I,+II,+and+IV+hydrogel+contact+lenses.">Uptake and release of dexamethasone phosphate from silicone hydrogel and group I, II, and IV hydrogel contact lenses.</a> Eye Contact Lens. 35, 260-267 (2009).</li><li>Lorentz, H., Heynen, M., Trieu, D., Hagedorn, S. J., Jones, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+impact+of+tear+film+components+on+in+vitro+lipid+uptake.">The impact of tear film components on in vitro lipid uptake.</a> Optom Vis Sci. 89, 856-867 (2012).</li><li>Hall, B., Phan, C. M., Subbaraman, L., Jones, L. W., Forrest, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Extraction+versus+in+situ+techniques+for+measuring+surface-adsorbed+lysozyme.">Extraction versus in situ techniques for measuring surface-adsorbed lysozyme.</a> Optom Vis Sci. 91, 1062-1070 (2014).</li><li>Mishima, S., Gasset, A., Klyce, S. D., Baum, J. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Determination+of+tear+volume+and+tear+flow.">Determination of tear volume and tear flow.</a> Invest Ophthalmol Vis Sci. 5, 264-276 (1966).</li><li>Nichols, J. 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=The+TFOS+international+workshop+on+contact+lens+discomfort:+executive+summary.">The TFOS international workshop on contact lens discomfort: executive summary.</a> Invest Ophthalmol Vis Sci. 54, 7-13 (2013).</li><li>Peng, C. C., Burke, M. T., Carbia, B. E., Plummer, C., Chauhan, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Extended+drug+delivery+by+contact+lenses+for+glaucoma+therapy.">Extended drug delivery by contact lenses for glaucoma therapy.</a> J Control Release. 162, 152-158 (2012).</li><li>Faschinger, C., Mossbock, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Continuous+24+h+monitoring+of+changes+in+intraocular+pressure+with+the+wireless+contact+lens+sensor+Triggerfish.+First+results+in+patients.">Continuous 24 h monitoring of changes in intraocular pressure with the wireless contact lens sensor Triggerfish. First results in patients.</a> Der Ophthalmologe : Zeitschrift der Deutschen Ophthalmologischen Gesellschaft. 107, 918-922 (2010).</li><li>Shaw, A. J., Davis, B. A., Collins, M. J., Carney, L. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+technique+to+measure+eyelid+pressure+using+piezoresistive+sensors.">A technique to measure eyelid pressure using piezoresistive sensors.</a> IEEE transactions on bio-medical engineering. 56, 2512-2517 (2009).</li><li>Liao, Y. T., Yao, H. F., Lingley, A., Parviz, B., Otis, B. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+3-mu+W+CMOS+glucose+sensor+for+wireless+contact-lens+tear+glucose+monitoring.">A 3-mu W CMOS glucose sensor for wireless contact-lens tear glucose monitoring.</a> Ieee J Solid-St Circ. 47, 335-344 (2012).</li><li>Coster, D. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Cornea. , (2002).</li><li>Parekh, 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=A+simplified+technique+for+in+situ+excision+of+cornea+and+evisceration+of+retinal+tissue+from+human+ocular+globe.">A simplified technique for in situ excision of cornea and evisceration of retinal tissue from human ocular globe.</a> Journal of visualized experiments : JoVE. , e3765 (2012).</li><li>Way, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Gear+and+pinion.">Gear and pinion.</a> US patent. , (1942).</li><li>Lorentz, H., 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=Contact+lens+physical+properties+and+lipid+deposition+in+a+novel+characterized+artificial+tear+solution.">Contact lens physical properties and lipid deposition in a novel characterized artificial tear solution.</a> Molecular vision. 17, 3392-3405 (2011).</li><li>Furukawa, R. E., Polse, K. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Changes+in+tear+flow+accompanying+aging.">Changes in tear flow accompanying aging.</a> American journal of optometry and physiological optics. 55, 69-74 (1978).</li><li>Bajgrowicz, M., Phan, C. M., Subbaraman, L., Jones, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Release+of+ciprofloxacin+and+moxifloxacin+from+daily+disposable+contact+lenses+from+an+in+vitro+eye+model.">Release of ciprofloxacin and moxifloxacin from daily disposable contact lenses from an in vitro eye model.</a> Invest Ophthalmol Vis Sci. , (2015).</li><li>Luensmann, D., Zhang, F., Subbaraman, L., Sheardown, H., Jones, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Localization+of+lysozyme+sorption+to+conventional+and+silicone+hydrogel+contact+lenses+using+confocal+microscopy.">Localization of lysozyme sorption to conventional and silicone hydrogel contact lenses using confocal microscopy.</a> Current eye research. 34, 683-697 (2009).</li><li>Tieppo, A., Pate, K. M., Byrne, M. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+vitro+controlled+release+of+an+anti-inflammatory+from+daily+disposable+therapeutic+contact+lenses+under+physiological+ocular+tear+flow.">In vitro controlled release of an anti-inflammatory from daily disposable therapeutic contact lenses under physiological ocular tear flow.</a> Eur J Pharm Biopharm. 81, 170-177 (2012).</li><li>Ali, 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=Zero-order+therapeutic+release+from+imprinted+hydrogel+contact+lenses+within+in+vitro+physiological+ocular+tear+flow.">Zero-order therapeutic release from imprinted hydrogel contact lenses within in vitro physiological ocular tear flow.</a> J Control Release. 124, 154-162 (2007).</li><li>White, C. J., McBride, M. K., Pate, K. M., Tieppo, A., Byrne, M. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Extended+release+of+high+molecular+weight+hydroxypropyl+methylcellulose+from+molecularly+imprinted,+extended+wear+silicone+hydrogel+contact+lenses.">Extended release of high molecular weight hydroxypropyl methylcellulose from molecularly imprinted, extended wear silicone hydrogel contact lenses.</a> Biomaterials. 32, 5698-5705 (2011).</li><li>Kaczmarek, J. C., Tieppo, A., White, C. J., Byrne, M. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Adjusting+biomaterial+composition+to+achieve+controlled+multiple-day+release+of+dexamethasone+from+an+extended-wear+silicone+hydrogel+contact+lens.">Adjusting biomaterial composition to achieve controlled multiple-day release of dexamethasone from an extended-wear silicone hydrogel contact lens.</a> J Biomater Sci Polym Ed. 25, 88-100 (2014).</li><li>Mohammadi, S., Postnikoff, C., Wright, A. M., Gorbet, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Design+and+development+of+an+in+vitro+tear+replenishment+system.">Design and development of an in vitro tear replenishment system.</a> Ann Biomed Eng. 42, 1923-1931 (2014).</li><li>Lorentz, H., Heynen, M., Khan, W., Trieu, D., Jones, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+impact+of+intermittent+air+exposure+on+lipid+deposition.">The impact of intermittent air exposure on lipid deposition.</a> Optom Vis Sci. 89, 1574-1581 (2012).</li><li>Peng, C. C., Fajardo, N. P., Razunguzwa, T., Radke, 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=In+vitro+spoilation+of+silicone-hydrogel+soft+contact+lenses+in+a+model-blink+cell.">In vitro spoilation of silicone-hydrogel soft contact lenses in a model-blink cell.</a> Optom Vis Sci. 92, 768-780 (2015).</li><li>Liu, 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=Dissolution+studies+of+poorly+soluble+drug+nanosuspensions+in+non-sink+conditions.">Dissolution studies of poorly soluble drug nanosuspensions in non-sink conditions.</a> AAPS PharmSciTech. 14, 748-756 (2013).</li></ol>

There are three critical steps within the protocol that require special attention: design and production of molds (section 1.1), platform assembly (section 2.2.1-2.2.3), and monitoring the experimental run (section 2.2.4-2.2.7). In terms of the design and production of molds (section 1.1), the eyeball piece should be designed according to the dimensions of a human cornea. However, it may require multiple prototypes of the mold before an eyeball piece can be created that perfectly fits a commercial contact lens (CL). In a...

Two significant areas of interest within the contact lens (CL) arena include discomfort and the development of novel CL applications. Elucidating the mechanisms underlying CL discomfort is an issue that has eluded the field for decades.8 The development of novel, functional CLs, such as drug-delivery devices1,3,9 and biosensors,10-12 is an area of growing interest, with substantial potential markets. In both circumstances, a sophisticated in vitro model would provide relevant information to assist with selecting appropriate lens materials or design characteristics during the development phase. Unfortunately, current in vitro models for evaluating CLs and other eye related applications are relatively crude and unsophisticated. Traditionally, in vitro CL studies evaluating tear film deposition or drug delivery are performed in static, large volume vials containing a fixed fluid volume, which greatly exceeds physiological amounts. Furthermore, this simple model lacks the natural tear flow component and the blinking reflex, both of which are defining factors of the ocular environment.
The development of a sophisticated, physiologically relevant eye &#34;model&#34; will necessitate a multi-disciplinary approach and require substantial in vivo validation. For these reasons, the fundamental framework for our in vitro eye model is highly versatile, such that the model can be continually improved through future upgrades and modulations. To date, the model is capable of simulating tear volume, tear flow, mechanical wear and air exposure. The aim is to create an in vitro model that will provide meaningful results, which is predictive and complimentary to in vivo and ex vivo observations.

<table border="0" cellpadding="0" cellspacing="0" width="1129">
	<tbody>
		<tr height="42">
			<td height="42" style="height:42px;width:281px;">Arduino Uno R3 (Atmega328 - assembled)</td>
			<td style="width:125px;">Adafruit</td>
			<td style="width:451px;">50</td>
			<td style="width:273px;">Board</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:281px;">Stepper motor</td>
			<td style="width:125px;">Adafruit</td>
			<td style="width:451px;">324</td>
			<td>Motor and Motor shield</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:281px;">Equal Leg Coupler 1.6mm 1/16&#34;</td>
			<td style="width:125px;">VWR</td>
			<td style="width:451px;">CA11009-280</td>
			<td>50 pcs of tube connector</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:281px;">Tubing PT/SIL 1/16&#34;x1/8&#34;</td>
			<td style="width:125px;">VWR</td>
			<td style="width:451px;">16211-316</td>
			<td>Case of 50feet</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:281px;">PDMS</td>
			<td style="width:125px;">Dow Corning</td>
			<td style="width:451px;">Sylgard 184 Solar Cell Encapsulation</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:281px;">Agarose, Type 1-A, low EEO</td>
			<td style="width:125px;">Sigma-Aldrich</td>
			<td style="width:451px;">A0169-25G</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:281px;">PHD UltraTM</td>
			<td style="width:125px;">Harvard Apparatus</td>
			<td style="width:451px;">703006</td>
			<td>MicroFluidic Pump</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:281px;">Bovine cornea</td>
			<td style="width:125px;">Cargill, Guelph/ON</td>
			<td style="width:451px;"></td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:281px;">Soldidworks</td>
			<td style="width:125px;">Dassault Systemes</td>
			<td style="width:451px;"></td>
			<td>Software</td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:281px;">3-D printing</td>
			<td style="width:125px;">University of Waterloo - 3D Print Centre</td>
			<td style="width:451px;"></td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:281px;">Dissection tools</td>
			<td style="width:125px;">Fine Science Tools</td>
			<td style="width:451px;"></td>
			<td>General dissection tools</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:281px;">Medium 199</td>
			<td style="width:125px;">Sigma-Aldrich</td>
			<td style="width:451px;"></td>
			<td>Culture medium storage for cornea</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:281px;">Fetal bovine serum</td>
			<td style="width:125px;">Thermo Fisher</td>
			<td style="width:451px;"></td>
			<td>Add to culture medium, 3% total volume</td>
		</tr>
	</tbody>
</table>

development of an in vitro ocular platform to test contact lenses

Currently, in vitro evaluations of contact lenses (CLs) for drug delivery are typically performed in large volume vials,1-6 which fail to mimic physiological tear volumes.7 The traditional model also lacks the natural tear flow component and the blinking reflex, both of which are defining factors of the ocular environment. The development of a novel model is described in this study, which consists of a unique 2-piece design, eyeball and eyelid piece, capable of mimicking physiological tear volume. The models are created from 3-D printed molds (Polytetrafluoroethylene or Teflon molds), which can be used to generate eye models from various polymers, such as polydimethylsiloxane (PDMS) and agar. Further modifications to the eye pieces, such as the integration of an explanted human or animal cornea or human corneal construct, will permit for more complex in vitro ocular studies. A commercial microfluidic syringe pump is integrated with the platform to emulate physiological tear secretion. Air exposure and mechanical wear are achieved using two mechanical actuators, of which one moves the eyelid piece laterally, and the other moves the eyeballeyepiece circularly. The model has been used to evaluate CLs for drug delivery and deposition of tear components on CLs.

The synthesized eye molds obtained from the machine shop and from 3-D printing are shown in Figure 1. These molds can be used with a variety of polymers, such as PDMS and agarose, to produce eyepieces with the desired properties. The motioned assembly of the eye model platform with a microfluidic syringe pump is shown in Figure 2. The platform simulates mechanical wear via the rotation of the eyeball piece, and air exposure through the lateral in and out ...

Watch this Scientific Journal Video about Development of an In Vitro Ocular Platform to Test Contact Lenses at JoVE.com

Development of an In Vitro Ocular Platform to Test Contact Lenses

Current in vitro models for evaluating contact lenses (CLs) and other eye-related applications are severely limited. The presented ocular platform simulates physiological tear flow, tear volume, air exposure and mechanical wear. This system is highly versatile and can be applied to various in vitro analyses with CLs.

Development of an In Vitro Ocular Platform to Test Contact Lenses

Currently, in vitro evaluations of contact lenses (CLs) for drug delivery are typically performed in large volume vials,1-6 which fail to mimic ...

Research

JoVE Journal

Bioengineering

Tissue Engineering of a Human 3D in vitro Tumor Test System

Tissue Engineering of a Human 3D in vitro Tumor Test System

Cancer is one of the leading causes of death worldwide.  Current therapeutic strategies are predominantly developed in 2D culture  systems, which ...

Development of Amelogenin-chitosan Hydrogel for In Vitro Enamel Regrowth with a Dense Interface

Development of Amelogenin-chitosan Hydrogel for In Vitro Enamel Regrowth with a Dense Interface

Biomimetic enamel reconstruction is a significant topic in material science and dentistry as a novel approach for the treatment of dental caries or ...

Eye Irritation Test (EIT) for Hazard Identification of Eye Irritating Chemicals using Reconstructed Human Cornea-like Epithelial (RhCE) Tissue Model

Eye Irritation Test EIT for Hazard Identification of Eye Irritating Chemicals using Reconstructed Human Cornea-like Epithelial RhCE Tissue Model

To comply with the Seventh Amendment to the EU Cosmetics Directive and EU REACH legislation, validated non-animal alternative methods for reliable and ...

In Vitro Model of Physiological and Pathological Blood Flow with Application to Investigations of Vascular Cell Remodeling

In Vitro Model of Physiological and Pathological Blood Flow with Application to Investigations of Vascular Cell Remodeling

Vascular disease is a common cause of death within the United States. Herein, we present a method to examine the contribution of flow dynamics towards ...

An In Vitro Organ Culture Model of the Murine Intervertebral Disc

An In Vitro Organ Culture Model of the Murine Intervertebral Disc

Intervertebral disc (IVD) degeneration is a significant contributor to low back pain. The IVD is a fibrocartilaginous joint that serves to transmit and ...

Assembly and Tracking of Microbial Community Development within a Microwell Array Platform

The development of microbial communities depends on a combination of complex deterministic and stochastic factors that can dramatically alter the spatial ...

Development of an Electrochemical DNA Biosensor to Detect a Foodborne Pathogen

Vibrio parahaemolyticus (V. parahaemolyticus) is a common foodborne pathogen that contributes to a large proportion of public health problems globally, ...

An Ultrahigh-throughput Microfluidic Platform for Single-cell Genome Sequencing

Sequencing technologies have undergone a paradigm shift from bulk to single-cell resolution in response to an evolving understanding of the role of ...

Rodent Behavioral Testing to Assess Functional Deficits Caused by Microelectrode Implantation in the Rat Motor Cortex

Medical devices implanted in the brain hold tremendous potential. As part of a Brain Machine Interface (BMI) system, intracortical microelectrodes ...

Advanced 3D Liver Models for In vitro Genotoxicity Testing Following Long-Term Nanomaterial Exposure

Due to the rapid development and implementation of a diverse array of engineered nanomaterials (ENM), exposure to ENM is inevitable and the development of ...