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Bose S, Phan CM, Rizwan M, Tse JW, Yim E, Jones L. Fabrication and Characterization of an Enzyme-Triggered, Therapeutic-Releasing Hydrogel Bandage Contact Lens Material. Pharmaceutics 2023; 16:26. [PMID: 38258038 PMCID: PMC10819205 DOI: 10.3390/pharmaceutics16010026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2023] [Revised: 12/19/2023] [Accepted: 12/21/2023] [Indexed: 01/24/2024] Open
Abstract
PURPOSE The purpose of this study was to develop an enzyme-triggered, therapeutic-releasing bandage contact lens material using a unique gelatin methacrylate formulation (GelMA+). METHODS Two GelMA+ formulations, 20% w/v, and 30% w/v concentrations, were prepared through UV polymerization. The physical properties of the material, including porosity, tensile strain, and swelling ratio, were characterized. The enzymatic degradation of the material was assessed in the presence of matrix metalloproteinase-9 (MMP-9) at concentrations ranging from 0 to 300 µg/mL. Cell viability, cell growth, and cytotoxicity on the GelMA+ gels were evaluated using the AlamarBlueTM assay and the LIVE/DEADTM Viability/Cytotoxicity kit staining with immortalized human corneal epithelial cells over 5 days. For drug release analysis, the 30% w/v gels were loaded with 3 µg of bovine lactoferrin (BLF) as a model drug, and its release was examined over 5 days under various MMP-9 concentrations. RESULTS The 30% w/v GelMA+ demonstrated higher crosslinking density, increased tensile strength, smaller pore size, and lower swelling ratio (p < 0.05). In contrast, the 20% w/v GelMA+ degraded at a significantly faster rate (p < 0.001), reaching almost complete degradation within 48 h in the presence of 300 µg/mL of MMP-9. No signs of cytotoxic effects were observed in the live/dead staining assay for either concentration after 5 days. However, the 30% w/v GelMA+ exhibited significantly higher cell viability (p < 0.05). The 30% w/v GelMA+ demonstrated sustained release of the BLF over 5 days. The release rate of BLF increased significantly with higher concentrations of MMP-9 (p < 0.001), corresponding to the degradation rate of the gels. DISCUSSION The release of BLF from GelMA+ gels was driven by a combination of diffusion and degradation of the material by MMP-9 enzymes. This work demonstrated that a GelMA+-based material that releases a therapeutic agent can be triggered by enzymes found in the tear fluid.
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Affiliation(s)
- Susmita Bose
- Centre for Ocular Research & Education (CORE), School of Optometry and Vision Science, University of Waterloo, 200 University Avenue West, Waterloo, ON N2L 3G1, Canada; (S.B.); (L.J.)
| | - Chau-Minh Phan
- Centre for Ocular Research & Education (CORE), School of Optometry and Vision Science, University of Waterloo, 200 University Avenue West, Waterloo, ON N2L 3G1, Canada; (S.B.); (L.J.)
- Centre for Eye and Vision Research (CEVR), 17W Hong Kong Science Park, Hong Kong, China
| | - Muhammad Rizwan
- Chemical Engineering, University of Waterloo, 200 University Avenue West, Waterloo, ON N2L 3G1, Canada; (M.R.); (J.W.T.); (E.Y.)
| | - John Waylon Tse
- Chemical Engineering, University of Waterloo, 200 University Avenue West, Waterloo, ON N2L 3G1, Canada; (M.R.); (J.W.T.); (E.Y.)
| | - Evelyn Yim
- Chemical Engineering, University of Waterloo, 200 University Avenue West, Waterloo, ON N2L 3G1, Canada; (M.R.); (J.W.T.); (E.Y.)
| | - Lyndon Jones
- Centre for Ocular Research & Education (CORE), School of Optometry and Vision Science, University of Waterloo, 200 University Avenue West, Waterloo, ON N2L 3G1, Canada; (S.B.); (L.J.)
- Centre for Eye and Vision Research (CEVR), 17W Hong Kong Science Park, Hong Kong, China
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Liu LC, Chen YH, Lu DW. Overview of Recent Advances in Nano-Based Ocular Drug Delivery. Int J Mol Sci 2023; 24:15352. [PMID: 37895032 PMCID: PMC10607833 DOI: 10.3390/ijms242015352] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Revised: 10/12/2023] [Accepted: 10/17/2023] [Indexed: 10/29/2023] Open
Abstract
Ocular diseases profoundly impact patients' vision and overall quality of life globally. However, effective ocular drug delivery presents formidable challenges within clinical pharmacology and biomaterial science, primarily due to the intricate anatomical and physiological barriers unique to the eye. In this comprehensive review, we aim to shed light on the anatomical and physiological features of the eye, emphasizing the natural barriers it presents to drug administration. Our goal is to provide a thorough overview of various characteristics inherent to each nano-based drug delivery system. These encompass nanomicelles, nanoparticles, nanosuspensions, nanoemulsions, microemulsions, nanofibers, dendrimers, liposomes, niosomes, nanowafers, contact lenses, hydrogels, microneedles, and innovative gene therapy approaches employing nano-based ocular delivery techniques. We delve into the biology and methodology of these systems, introducing their clinical applications over the past decade. Furthermore, we discuss the advantages and challenges illuminated by recent studies. While nano-based drug delivery systems for ophthalmic formulations are gaining increasing attention, further research is imperative to address potential safety and toxicity concerns.
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Affiliation(s)
| | | | - Da-Wen Lu
- Department of Ophthalmology, Tri-Service General Hospital, National Defense Medical Center, Taipei 11490, Taiwan; (L.-C.L.); (Y.-H.C.)
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3
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Torun H, Fazla B, Arman S, Ozdalgic B, Yetisen AK, Tasoglu S. Microfluidic contact lenses for ocular diagnostics and drug delivery. NANO SELECT 2022. [DOI: 10.1002/nano.202200202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Affiliation(s)
- Hulya Torun
- Graduate School of Sciences and Engineering Koc University Istanbul Turkey
- Koc University Research Center for Translational Medicine Koc University Istanbul Turkey
| | - Bartu Fazla
- Graduate School of Sciences and Engineering Koc University Istanbul Turkey
| | - Samaneh Arman
- Graduate School of Sciences and Engineering Koc University Istanbul Turkey
| | - Berin Ozdalgic
- Koc University Research Center for Translational Medicine Koc University Istanbul Turkey
- Department of Mechanical Engineering, Engineering Faculty Koc University Istanbul Turkey
- Division of Opticianry, The School of Medical Services and Techniques Dogus University Istanbul Turkey
| | - Ali K. Yetisen
- Department of Chemical Engineering Imperial College London London UK
| | - Savas Tasoglu
- Koc University Research Center for Translational Medicine Koc University Istanbul Turkey
- Department of Mechanical Engineering, Engineering Faculty Koc University Istanbul Turkey
- Arcelik Research Center for Creative Industries (KUAR) Koc University Istanbul Turkey
- Institute of Biomedical Engineering Bogazici University Istanbul Turkey
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Pereira-da-Mota AF, Phan CM, Concheiro A, Jones L, Alvarez-Lorenzo C. Testing drug release from medicated contact lenses: The missing link to predict in vivo performance. J Control Release 2022; 343:672-702. [DOI: 10.1016/j.jconrel.2022.02.014] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Revised: 02/09/2022] [Accepted: 02/10/2022] [Indexed: 12/13/2022]
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Chang WH, Liu PY, Lin DE, Jiang YT, Lu CJ, Hsu YHH. Dynamic Protein Adsorption-Desorption Analysis of Contact Lenses in a Three-Dimensional-Printed Eye Model. Macromol Res 2022. [DOI: 10.1007/s13233-022-0003-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Tuft S, Somerville TF, Li JPO, Neal T, De S, Horsburgh MJ, Fothergill JL, Foulkes D, Kaye S. Bacterial keratitis: identifying the areas of clinical uncertainty. Prog Retin Eye Res 2021; 89:101031. [PMID: 34915112 DOI: 10.1016/j.preteyeres.2021.101031] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Revised: 11/24/2021] [Accepted: 11/29/2021] [Indexed: 12/12/2022]
Abstract
Bacterial keratitis is a common corneal infection that is treated with topical antimicrobials. By the time of presentation there may already be severe visual loss from corneal ulceration and opacity, which may persist despite treatment. There are significant differences in the associated risk factors and the bacterial isolates between high income and low- or middle-income countries, so that general management guidelines may not be appropriate. Although the diagnosis of bacterial keratitis may seem intuitive there are multiple uncertainties about the criteria that are used, which impacts the interpretation of investigations and recruitment to clinical studies. Importantly, the concept that bacterial keratitis can only be confirmed by culture ignores the approximately 50% of cases clinically consistent with bacterial keratitis in which investigations are negative. The aetiology of these culture-negative cases is unknown. Currently, the estimation of bacterial susceptibility to antimicrobials is based on data from systemic administration and achievable serum or tissue concentrations, rather than relevant corneal concentrations and biological activity in the cornea. The provision to the clinician of minimum inhibitory concentrations of the antimicrobials for the isolated bacteria would be an important step forward. An increase in the prevalence of antimicrobial resistance is a concern, but the effect this has on disease outcomes is yet unclear. Virulence factors are not routinely assessed although they may affect the pathogenicity of bacteria within species and affect outcomes. New technologies have been developed to detect and kill bacteria, and their application to bacterial keratitis is discussed. In this review we present the multiple areas of clinical uncertainty that hamper research and the clinical management of bacterial keratitis, and we address some of the assumptions and dogma that have become established in the literature.
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Affiliation(s)
- Stephen Tuft
- Moorfields Eye Hospital NHS Foundation Trust, 162 City Road, London, EC1V 2PD, UK.
| | - Tobi F Somerville
- Department of Eye and Vision Sciences, University of Liverpool, 6 West Derby Street, Liverpool, L7 8TX, UK.
| | - Ji-Peng Olivia Li
- Moorfields Eye Hospital NHS Foundation Trust, 162 City Road, London, EC1V 2PD, UK.
| | - Timothy Neal
- Department of Clinical Microbiology, Liverpool Clinical Laboratories, Liverpool University Hospital NHS Foundation Trust, Prescot Street, Liverpool, L7 8XP, UK.
| | - Surjo De
- Department of Clinical Microbiology, University College London Hospitals NHS Foundation Trust, 250 Euston Road, London, NW1 2PG, UK.
| | - Malcolm J Horsburgh
- Department of Infection and Microbiomes, University of Liverpool, Crown Street, Liverpool, L69 7BX, UK.
| | - Joanne L Fothergill
- Department of Eye and Vision Sciences, University of Liverpool, 6 West Derby Street, Liverpool, L7 8TX, UK.
| | - Daniel Foulkes
- Department of Eye and Vision Sciences, University of Liverpool, 6 West Derby Street, Liverpool, L7 8TX, UK.
| | - Stephen Kaye
- Department of Eye and Vision Sciences, University of Liverpool, 6 West Derby Street, Liverpool, L7 8TX, UK.
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Rykowska I, Nowak I, Nowak R. Soft Contact Lenses as Drug Delivery Systems: A Review. Molecules 2021; 26:5577. [PMID: 34577045 PMCID: PMC8472272 DOI: 10.3390/molecules26185577] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Revised: 09/10/2021] [Accepted: 09/11/2021] [Indexed: 02/07/2023] Open
Abstract
This review describes the role of contact lenses as an innovative drug delivery system in treating eye diseases. Current ophthalmic drug delivery systems are inadequate, particularly eye drops, which allow about 95% of the active substance to be lost through tear drainage. According to the literature, many interdisciplinary studies have been carried out on the ability of contact lenses to increase the penetration of topical therapeutic agents. Contact lenses limit drug loss by releasing the medicine into two layers of tears on either side of the contact lens, eventually extending the time of contact with the ocular surface. Thanks to weighted soft contact lenses, a continuous release of the drug over an extended period is possible. This article reviewed the various techniques to deliver medications through contact lenses, examining their advantages and disadvantages. In addition, the potential of drug delivery systems based on contact lenses has been extensively studied.
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Affiliation(s)
- Iwona Rykowska
- Faculty of Chemistry, Adam Mickiewicz University, Uniwersytetu Poznańskiego 8, 61-614 Poznań, Poland;
| | - Iwona Nowak
- Faculty of Chemistry, Adam Mickiewicz University, Uniwersytetu Poznańskiego 8, 61-614 Poznań, Poland;
| | - Rafał Nowak
- Eye Department, J. Strus City Hospital, Szwajcarska 3, 61-285 Poznań, Poland;
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Chan VWY, Phan CM, Ngo W, Jones L. Lysozyme Deposition on Contact Lenses in an In Vitro Blink-Simulation Eye Model Versus a Static Vial Deposition Model. Eye Contact Lens 2021; 47:388-393. [PMID: 33840748 DOI: 10.1097/icl.0000000000000784] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/07/2021] [Indexed: 11/26/2022]
Abstract
PURPOSE To evaluate active lysozyme deposition on daily disposable (DD) contact lenses (CL) using a novel in vitro blink model. METHODS Three conventional hydrogel DD CL materials (etafilcon A, omafilcon A, nelfilcon A) and three silicone hydrogel DD CL materials (delefilcon A, senofilcon A, somofilcon A) were tested. The device blink rate was set to 6 blinks/min with a tear flow rate of 1 μL/min using an artificial tear solution (ATS) containing lysozyme and other typical tear film components. After incubation at 2, 4, or 8 hr, lenses were removed, and lysozyme activity was measured. A separate experiment was conducted with lenses incubated in a static vial containing 480 μL of ATS. RESULTS Etafilcon A deposited significantly higher amounts of active lysozyme (402±102 μg/lens) than other lens materials after 8 hr (P<0.0001). Etafilcon A had a higher amount of active lysozyme using the blink model compared with the static vial (P=0.0435), whereas somofilcon A (P=0.0076) and senofilcon A (P=0.0019) had a higher amount of lysozyme activity in the vial compared with the blink model. CONCLUSION The blink model can be tuned to provide quantitative data that closely mimics ex vivo studies and can be used to model deposition of lysozyme on CL materials.
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Affiliation(s)
- Vivian W Y Chan
- Centre for Ocular Research and Education (CORE) (V.W.Y.C., C.-M.P., W.N., L.J.), School of Optometry and Vision Science, University of Waterloo, Waterloo, ON, Canada ; and Centre for Eye and Vision Research (CEVR) (C.-M.P., W.N., L.J.), Hong Kong, China
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Jones L, Hui A, Phan CM, Read ML, Azar D, Buch J, Ciolino JB, Naroo SA, Pall B, Romond K, Sankaridurg P, Schnider CM, Terry L, Willcox M. CLEAR - Contact lens technologies of the future. Cont Lens Anterior Eye 2021; 44:398-430. [PMID: 33775384 DOI: 10.1016/j.clae.2021.02.007] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Accepted: 02/01/2021] [Indexed: 12/20/2022]
Abstract
Contact lenses in the future will likely have functions other than correction of refractive error. Lenses designed to control the development of myopia are already commercially available. Contact lenses as drug delivery devices and powered through advancements in nanotechnology will open up further opportunities for unique uses of contact lenses. This review examines the use, or potential use, of contact lenses aside from their role to correct refractive error. Contact lenses can be used to detect systemic and ocular surface diseases, treat and manage various ocular conditions and as devices that can correct presbyopia, control the development of myopia or be used for augmented vision. There is also discussion of new developments in contact lens packaging and storage cases. The use of contact lenses as devices to detect systemic disease has mostly focussed on detecting changes to glucose levels in tears for monitoring diabetic control. Glucose can be detected using changes in colour, fluorescence or generation of electric signals by embedded sensors such as boronic acid, concanavalin A or glucose oxidase. Contact lenses that have gained regulatory approval can measure changes in intraocular pressure to monitor glaucoma by measuring small changes in corneal shape. Challenges include integrating sensors into contact lenses and detecting the signals generated. Various techniques are used to optimise uptake and release of the drugs to the ocular surface to treat diseases such as dry eye, glaucoma, infection and allergy. Contact lenses that either mechanically or electronically change their shape are being investigated for the management of presbyopia. Contact lenses that slow the development of myopia are based upon incorporating concentric rings of plus power, peripheral optical zone(s) with add power or non-monotonic variations in power. Various forms of these lenses have shown a reduction in myopia in clinical trials and are available in various markets.
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Affiliation(s)
- Lyndon Jones
- Centre for Ocular Research & Education (CORE), School of Optometry & Vision Science, University of Waterloo, Waterloo, Canada; Centre for Eye and Vision Research (CEVR), 17W Hong Kong Science Park, Hong Kong.
| | - Alex Hui
- School of Optometry and Vision Science, UNSW Sydney, Sydney, NSW, Australia
| | - Chau-Minh Phan
- Centre for Ocular Research & Education (CORE), School of Optometry & Vision Science, University of Waterloo, Waterloo, Canada; Centre for Eye and Vision Research (CEVR), 17W Hong Kong Science Park, Hong Kong
| | - Michael L Read
- Eurolens Research, Division of Pharmacy and Optometry, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, UK
| | - Dimitri Azar
- Department of Ophthalmology and Visual Sciences, University of Illinois College of Medicine, Chicago, IL, USA; Verily Life Sciences, San Francisco, CA, USA
| | - John Buch
- Johnson & Johnson Vision Care, Jacksonville, FL, USA
| | - Joseph B Ciolino
- Department of Ophthalmology, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA, USA
| | - Shehzad A Naroo
- College of Health and Life Sciences, Aston University, Birmingham B4 7ET, UK
| | - Brian Pall
- Johnson & Johnson Vision Care, Jacksonville, FL, USA
| | - Kathleen Romond
- Department of Ophthalmology and Visual Sciences, University of Illinois College of Medicine, Chicago, IL, USA
| | - Padmaja Sankaridurg
- School of Optometry and Vision Science, UNSW Sydney, Sydney, NSW, Australia; Brien Holden Vision Institute, Sydney, Australia
| | | | - Louise Terry
- School of Optometry and Vision Sciences, Cardiff University, UK
| | - Mark Willcox
- School of Optometry and Vision Science, UNSW Sydney, Sydney, NSW, Australia
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Phan CM, Shukla M, Walther H, Heynen M, Suh D, Jones L. Development of an In Vitro Blink Model for Ophthalmic Drug Delivery. Pharmaceutics 2021; 13:pharmaceutics13030300. [PMID: 33668884 PMCID: PMC7996515 DOI: 10.3390/pharmaceutics13030300] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Revised: 02/19/2021] [Accepted: 02/21/2021] [Indexed: 02/07/2023] Open
Abstract
Purpose: The purpose of this study was to develop an advanced in vitro blink model that can be used to examine the release of a wide variety of components (for example, topical ophthalmic drugs, comfort-inducing agents) from soft contact lenses. Methods: The model was designed using computer-aided design software and printed using a stereolithography 3D printer. The eyelid and eyeball were synthesized from polyvinyl alcohol and silicone material, respectively. Simulated tear fluid was infused through tubing attached to the eyelid using a syringe pump. With each blink cycle, the eyelid slides and flexes across the eyeball to create an artificial tear film layer. The flow-through fluid was collected using a specialized trough. Two contact lenses, etafilcon A and senofilcon A, were incubated in 2 mL of a water-soluble red dye for 24 h and then placed on the eye model (n = 3). The release of the dye was measured over 24 h using a tear flow rate of 5 µL/min. Results: Approximately 25% of the fluid that flowed over the eye model was lost due to evaporation, nonspecific absorption, and residual dead volume. Senofilcon A absorbed more dye (47.6 ± 2.7 µL) than etafilcon A (22.3 ± 2.0 µL). For etafilcon A, the release of the dye followed a burst-plateau profile in the vial but was sustained in the eye model. For senofilcon A, the release of the dye was sustained in both the vial and the eye model, though more dye was released in the vial (p < 0.05). Overall, the release of the dye from the contact lenses was higher in the vial compared with the eye model (p < 0.05). Conclusion: The blink model developed in this study could be used to measure the release of topical ophthalmic drugs or comfort agents from contact lenses. Simulation of a blink mechanism, an artificial tear film, and nonspecific absorption in an eye model may provide better results than a simple, static vial incubation model.
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Affiliation(s)
- Chau-Minh Phan
- Centre for Ocular Research & Education (CORE), School of Optometry and Vision Science, University of Waterloo, 200 University Avenue West, Waterloo, ON N2L 3G1, Canada; (M.S.); (H.W.); (M.H.); (D.S.); (L.J.)
- Centre for Eye and Vision Research (CEVR), 17W Hong Kong Science Park, Hong Kong
- Correspondence: ; Tel.: +1-519-888-4567 (ext. 37009)
| | - Manish Shukla
- Centre for Ocular Research & Education (CORE), School of Optometry and Vision Science, University of Waterloo, 200 University Avenue West, Waterloo, ON N2L 3G1, Canada; (M.S.); (H.W.); (M.H.); (D.S.); (L.J.)
- Centre for Eye and Vision Research (CEVR), 17W Hong Kong Science Park, Hong Kong
| | - Hendrik Walther
- Centre for Ocular Research & Education (CORE), School of Optometry and Vision Science, University of Waterloo, 200 University Avenue West, Waterloo, ON N2L 3G1, Canada; (M.S.); (H.W.); (M.H.); (D.S.); (L.J.)
| | - Miriam Heynen
- Centre for Ocular Research & Education (CORE), School of Optometry and Vision Science, University of Waterloo, 200 University Avenue West, Waterloo, ON N2L 3G1, Canada; (M.S.); (H.W.); (M.H.); (D.S.); (L.J.)
| | - David Suh
- Centre for Ocular Research & Education (CORE), School of Optometry and Vision Science, University of Waterloo, 200 University Avenue West, Waterloo, ON N2L 3G1, Canada; (M.S.); (H.W.); (M.H.); (D.S.); (L.J.)
| | - Lyndon Jones
- Centre for Ocular Research & Education (CORE), School of Optometry and Vision Science, University of Waterloo, 200 University Avenue West, Waterloo, ON N2L 3G1, Canada; (M.S.); (H.W.); (M.H.); (D.S.); (L.J.)
- Centre for Eye and Vision Research (CEVR), 17W Hong Kong Science Park, Hong Kong
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Phan CM, Qiao H, Yee A, Jones L. Deposition of Fluorescently Tagged Lysozyme on Contact Lenses in a Physiological Blink Model. Eye Contact Lens 2021; 47:127-133. [PMID: 31789754 DOI: 10.1097/icl.0000000000000683] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/02/2019] [Indexed: 11/25/2022]
Abstract
PURPOSE To visualize the deposition of fluorescein isothiocyanate (FITC) lysozyme on daily disposable contact lenses (CLs) using a novel blink model. METHODS Three daily disposable conventional hydrogel CLs (etafilcon A, omafilcon A, and nelfilcon A) and three silicone hydrogel CLs (delefilcon A, senofilcon A, and somofilcon A) were evaluated in the study. The CLs were mounted onto a novel blink model and exposed to an artificial tear solution containing FITC lysozyme for 2 and 10 hr. The flow rate and blink speed were set to 1 μL/min and 6 blinks/min, respectively. After the incubation period, a 5-mm-diameter disc was punched out from the center of the lens and mounted on a microscope slide. The slides were imaged using the Zeiss 510 Meta confocal laser scanning microscope, which scanned the lens from the front to the back surface at 5-μm increments. RESULTS There was an increase in deposition of FITC lysozyme for all lens types with increasing incubation time (P<0.05), with the exception of somofilcon A, which did not show statistical significance between 2 and 10 hr (P>0.05). The conventional hydrogel CLs deposited higher amounts of FITC lysozyme than the silicone hydrogel CLs (P<0.001), with etafilcon A depositing the highest at all time points (P<0.05). Interestingly, at the 2-hr incubation time, most CLs showed a higher amount of deposition at the front surface than the back surface of the lens. In particular, etafilcon A showed preferred deposition at the front surface at all time points. CONCLUSION The results suggest that there is differential deposition at the front surface of the CL, which is exposed to the prelens tear film, compared with the back surface of the CL, which is exposed to the postlens tear film. Therefore, it may be beneficial to design CL materials with differing surface properties for the front and back surfaces of the CL to enhance interactions with the tear film and ocular surface.
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Affiliation(s)
- Chau-Minh Phan
- Centre for Ocular Research and Education (CORE), School of Optometry and Vision Science, University of Waterloo, Waterloo, Ontario, Canada
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12
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Fan X, Torres-Luna C, Azadi M, Domszy R, Hu N, Yang A, David AE. Evaluation of commercial soft contact lenses for ocular drug delivery: A review. Acta Biomater 2020; 115:60-74. [PMID: 32853799 DOI: 10.1016/j.actbio.2020.08.025] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Revised: 08/13/2020] [Accepted: 08/18/2020] [Indexed: 02/07/2023]
Abstract
Soft contact lenses have generated growing interest in ocular drug delivery due to their potential to enhance drug bioavailability in ocular tissues. Commercially available soft contact lenses offer several advantages for ocular drug delivery as they are manufactured on a large scale, which guarantees the availability of a consistent and reproducible product, and their favorable safety profile is well-established through broad clinical use. Here we review the rationale for using commercially available soft contact lenses for ocular drug delivery; summarize the evolution of the materials used in contact lens fabrication; and explore various methods used to improve the drug release characteristics and its tissue penetration. While significant progress has been made, several issues still require further attention for the commercial launch of a viable drug-eluting contact lens product, including control of initial burst release, shelf-life stability, and drug loss during processing or storage.
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13
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Khan SA, Lee CS. Recent progress and strategies to develop antimicrobial contact lenses and lens cases for different types of microbial keratitis. Acta Biomater 2020; 113:101-118. [PMID: 32622052 DOI: 10.1016/j.actbio.2020.06.039] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2020] [Revised: 06/24/2020] [Accepted: 06/25/2020] [Indexed: 12/16/2022]
Abstract
Although contact lenses are widely used for vision correction, they are also the primary cause of a number of ocular diseases such as microbial keratitis (MK), etc. and inflammatory events such as infiltrative keratitis (IK), contact lens acute red eye (CLARE), contact lens-induced peripheral ulcer (CLPU), etc. These diseases and infiltrative events often result from microbial contamination of lens care solutions and lens cases that can be exacerbated by unsanitary lens care and extended lens wear. The treatment of microbial biofilms (MBs) on lens cases and contact lenses are complicated and challenging due to their resistance to conventional antimicrobial lens care solutions. More importantly, MK caused by MBs can lead to acute visual damage or even vision impairment. Therefore, the development of lens cases, lens care solutions, and contact lenses with effective antimicrobial performance against MK will contribute to the safe use of contact lenses. This review article summarizes and discusses different chemical approaches for the development of antimicrobial contact lenses and lens cases employing passive surface modifications, antimicrobial peptides, free-radical fabricating agents, quorum sensing quenchers, antibiotics, antifungal drugs and various metals and coatings with antimicrobial nanomaterials. The benefits and shortcomings of these approaches are assessed, and alternative solutions for future developments are discussed.
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Affiliation(s)
- Shakeel Ahmad Khan
- Center of Super-Diamond and Advanced Films (COSDAF), Department of Chemistry, City University of Hong Kong, 83 Tat Chee Avenue, Kowloon, Hong Kong
| | - Chun-Sing Lee
- Center of Super-Diamond and Advanced Films (COSDAF), Department of Chemistry, City University of Hong Kong, 83 Tat Chee Avenue, Kowloon, Hong Kong.
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Horne RR, Rich JT, Bradley MW, Pitt WG. Latanoprost uptake and release from commercial contact lenses. JOURNAL OF BIOMATERIALS SCIENCE-POLYMER EDITION 2019; 31:1-19. [DOI: 10.1080/09205063.2019.1669126] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Affiliation(s)
- Ryan R. Horne
- Chemical Engineering Department, Brigham Young University, Provo, UT, USA
- Carver College of Medicine, University of Iowa, Iowa City, IA, USA
| | - Joseph T. Rich
- Chemical Engineering Department, Brigham Young University, Provo, UT, USA
| | - Matthew W. Bradley
- Chemical Engineering Department, Brigham Young University, Provo, UT, USA
| | - William G. Pitt
- Chemical Engineering Department, Brigham Young University, Provo, UT, USA
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Phan CM, Walther H, Qiao H, Shinde R, Jones L. Development of an Eye Model With a Physiological Blink Mechanism. Transl Vis Sci Technol 2019; 8:1. [PMID: 31534830 PMCID: PMC6727780 DOI: 10.1167/tvst.8.5.1] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2019] [Accepted: 07/04/2019] [Indexed: 01/26/2023] Open
Abstract
Purpose To develop an eye model with a physiological blink mechanism. Methods All parts of the eye model were designed using computer-aided design software. The eyelid consisted of a unique 3D printed structure containing teeth to physically secure a flexible membrane. Both the eyeball and eyelid membrane were synthesized using polyvinyl alcohol (PVA). Four molecular weights of PVA (89–98, 85–124, 130, and 146–186 kDa) were tested at a range of concentrations between 5% and 30% weight/volume. The wettability and water content of these materials were compared with the bovine cornea and sclera. The model was connected to a microfluidic pump, which delivers artificial tear solution (ATS) to the eyelid. A corneal topographer was used to evaluate the tear break-up and tear film regeneration. Results The eyelid flexes and slides across the eyeball during each blink, which ensures direct contact between the two surfaces. When loaded with an ATS, this mechanism evenly spreads the solution over the eyeball to generate an artificial tear film. The artificial tear film in this eye model had a tear break-up time (TBUT) of 5.13 ± 0.09 seconds at 1.4 μL/min flow rate, 6 blinks/min, and <25% humidity. Conclusions This model simulates a physiological blink actuation and an artificial tear film layer. Future studies will examine variations in flow rates and ATS composition to simulate clinical values of TBUT. Translational Relevance The eye model could be used to study in vitro TBUT, tear deposition, and simple drug delivery.
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Affiliation(s)
- Chau-Min Phan
- Centre for Ocular Research & Education (CORE), School of Optometry and Vision Science, University of Waterloo, Waterloo, ON, Canada
| | - Hendri Walther
- Centre for Ocular Research & Education (CORE), School of Optometry and Vision Science, University of Waterloo, Waterloo, ON, Canada
| | - Ha Qiao
- Centre for Ocular Research & Education (CORE), School of Optometry and Vision Science, University of Waterloo, Waterloo, ON, Canada
| | - Ra Shinde
- Manipal Academy of Higher Education, Manipal Institute of Technology, Madhav Nagar, Manipal, Karnataka, India
| | - Lyndo Jones
- Centre for Ocular Research & Education (CORE), School of Optometry and Vision Science, University of Waterloo, Waterloo, ON, Canada
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16
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Pawar V, Bulbake U, Khan W, Srivastava R. Chitosan sponges as a sustained release carrier system for the prophylaxis of orthopedic implant-associated infections. Int J Biol Macromol 2019; 134:100-112. [DOI: 10.1016/j.ijbiomac.2019.04.190] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2019] [Revised: 04/13/2019] [Accepted: 04/29/2019] [Indexed: 12/31/2022]
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17
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Uptake and Release of Polyvinyl Alcohol from Hydrogel Daily Disposable Contact Lenses. Optom Vis Sci 2019; 96:180-186. [DOI: 10.1097/opx.0000000000001351] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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18
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Mulas K, Stefanowicz Z, Oledzka E, Sobczak M. Current state of the polymeric delivery systems of fluoroquinolones – A review. J Control Release 2019; 294:195-215. [DOI: 10.1016/j.jconrel.2018.12.021] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Revised: 12/11/2018] [Accepted: 12/12/2018] [Indexed: 01/29/2023]
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19
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Phan CM, Walther H, Smith RW, Riederer D, Lau C, Osborn Lorenz K, Subbaraman LN, Jones L. Determination of the release of PEG and HPMC from nelfilcon A daily disposable contact lenses using a novel in vitro eye model. JOURNAL OF BIOMATERIALS SCIENCE-POLYMER EDITION 2018; 29:2124-2136. [PMID: 30157706 DOI: 10.1080/09205063.2018.1514192] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
The traditional method to measure release of components from CLs is a vial containing a static volume of PBS (phosphate buffered saline). However, this model does not simulate physiologically relevant tear volume and natural tear flow, air exposure, and mechanical rubbing. These factors can significantly impact release kinetics. We have developed an in vitro eye model (OcuFlow) that simulates these parameters. The aim of the study was to measure the release of PEG (polyethylene glycol), and HPMC (hydroxypropyl methylcellulose) from a daily disposable hydrogel contact lens material (nelfilcon A; Dailies AquaComfort PLUS; DACP;) over 24 hrs using the OcuFlow platform. The elution of PEG and HPMC from DACP lenses was analyzed using LCMS (liquid chromatography mass spectrometry). The release of all wetting agents from the lenses followed a burst release pattern, which occurred within the first 1.5 hrs (P < 0.05). The release of PEG was greater than that of HPMC (P < 0.05). The amount of PEG and HPMC released at any given time was less than 1% of the amount in the blister pack solution. Our results suggest that HPMC and PEG are rapidly released from the CL.
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Affiliation(s)
- Chau-Minh Phan
- a Centre for Ocular Research & Education (CORE) - formerly Centre for Contact Lens Research (CCLR) , School of Optometry and Vision Science , Waterloo , ON , Canada
| | - Hendrik Walther
- a Centre for Ocular Research & Education (CORE) - formerly Centre for Contact Lens Research (CCLR) , School of Optometry and Vision Science , Waterloo , ON , Canada
| | - Richard W Smith
- b University of Waterloo Mass Spectrometry Facility, Department of Chemistry , University of Waterloo , Waterloo , ON , Canada
| | | | - Charis Lau
- c Johnson & Johnson Vision , Jacksonville , FL , USA
| | | | - Lakshman N Subbaraman
- a Centre for Ocular Research & Education (CORE) - formerly Centre for Contact Lens Research (CCLR) , School of Optometry and Vision Science , Waterloo , ON , Canada
| | - Lyndon Jones
- a Centre for Ocular Research & Education (CORE) - formerly Centre for Contact Lens Research (CCLR) , School of Optometry and Vision Science , Waterloo , ON , Canada
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20
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Depth Profile Assessment of the Early Phase Deposition of Lysozyme on Soft Contact Lens Materials Using a Novel In Vitro Eye Model. Eye Contact Lens 2018; 44 Suppl 2:S11-S18. [DOI: 10.1097/icl.0000000000000397] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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21
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Zhou S, Hunt KM, Grewal AS, Brothers KM, Dhaliwal DK, Shanks RMQ. Release of Moxifloxacin From Corneal Collagen Shields. Eye Contact Lens 2018; 44 Suppl 2:S143-S147. [PMID: 28945653 PMCID: PMC5862718 DOI: 10.1097/icl.0000000000000421] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVES To investigate the diffusion of moxifloxacin through bandage contact lenses (BCLs) versus corneal collagen shields (CSs), the relative ability of BCLs and CSs to release moxifloxacin, and the potential of release of moxifloxacin from CSs in the clinical setting. METHODS Using an in vitro model, the diffusion of 5% moxifloxacin across BCLs and CSs was compared. Next, the amount of drug release from BCLs and CSs soaked in 0.5% moxifloxacin was measured. Finally, based on a clinical model, CSs were soaked in Vigamox (commercial moxifloxacin) and the total concentration released was detected. Collagen shields remained intact after 24 hr; therefore, enzymatic digestion and mechanical grinding of the CS were performed to determine whether further drug could be released. The concentration of moxifloxacin was measured using a spectrophotometer at set time points up to 24 hr. RESULTS In the diffusion assay, 35.7±10.5% diffused through the BCLs and 36.2±11.8% diffused through the CSs (P=0.77). The absorption assay demonstrated at 120 min, a total of 33.3±6.77 μg/mL was released from BCLs compared with 45.8±5.2 μg/mL from the CSs (P=0.0008). In vitro experiments to simulate clinical application of Vigamox-soaked CS found the concentration of moxifloxacin released of 127.7±7.25 μg/mL in 2 mL of phosphate-buffered saline over 24 hr. CONCLUSIONS Moxifloxacin diffuses through BCLs and CSs at similar rates; however, CSs have greater capacity to absorb and release moxifloxacin compared with BCLs. Vigamox-soaked CSs released 250 μg of moxifloxacin and may be a useful method to prevent endophthalmitis.
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Affiliation(s)
- Siwei Zhou
- Department of Ophthalmology, Ophthalmology Residency Program (S.Z.), University of Pittsburgh Medical Center Pittsburgh, PA; The Charles T. Campbell Ophthalmic Microbiology Laboratory (K.M.H., A.S.G., K.M.B., D.K.D, R.M.Q.S.), UPMC Eye Center, Ophthalmology and Visual Sciences Research Center, Department of Ophthalmology (OVSRC), University of Pittsburgh School of Medicine, Pittsburgh, PA; and Fox Center for Vision Restoration (K.M.B., D.K.D., R.M.Q.S.), Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh PA
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22
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Lin A, Rhee MK, Akpek EK, Amescua G, Farid M, Garcia-Ferrer FJ, Varu DM, Musch DC, Dunn SP, Mah FS. Bacterial Keratitis Preferred Practice Pattern®. Ophthalmology 2018; 126:P1-P55. [PMID: 30366799 DOI: 10.1016/j.ophtha.2018.10.018] [Citation(s) in RCA: 123] [Impact Index Per Article: 20.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2018] [Accepted: 10/05/2018] [Indexed: 10/28/2022] Open
Affiliation(s)
- Amy Lin
- John A. Moran Eye Center, University of Utah, Salt Lake City, Utah, USA
| | - Michelle K Rhee
- Department of Ophthalmology, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Esen K Akpek
- The Wilmer Eye Institute, Johns Hopkins University, Baltimore, Maryland
| | - Guillermo Amescua
- Department of Ophthalmology, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, Florida
| | - Marjan Farid
- Gavin Herbert Eye Institute, Department of Ophthalmology, University of California, Irvine, California
| | | | | | - David C Musch
- Department of Ophthalmology and Visual Sciences, University of Michigan, Ann Arbor, Michigan
| | | | - Francis S Mah
- Departments of Cornea and External Diseases, Scripps Clinic Torrey Pines, La Jolla, California
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23
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Phan CM, Walther H, Riederer D, Lau C, Lorenz KO, Subbaraman LN, Jones L. Analysis of polyvinyl alcohol release from commercially available daily disposable contact lenses using an in vitro eye model. J Biomed Mater Res B Appl Biomater 2018; 107:1662-1668. [PMID: 30325095 PMCID: PMC6587498 DOI: 10.1002/jbm.b.34259] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2018] [Revised: 09/10/2018] [Accepted: 09/23/2018] [Indexed: 11/11/2022]
Abstract
The purpose of this work was to determine the release of polyvinyl alcohol (PVA) from etafilcon A, omafilcon A, and nelfilcon A daily disposable hydrogel contact lenses using a novel in vitro model. PVA is an ocular lubricant that can be found in multiple formulations of artificial tears. Nelfilcon A innately contains PVA, so only the release of PVA from this lens was evaluated. Etafilcon A and omafilcon A lenses were incubated in a PBS solution containing PVA. The release of PVA was evaluated using a novel in vitro blink platform with Milli‐Q water and PBS under various blink conditions and flow rates. Nelfilcon A lenses significantly released more PVA than other lenses at 0.5 and 1.5 h in both PBS and Milli‐Q water (p < 0.001). For nelfilcon A, there was no statistical significance between the release profiles of PVA between the blink and no‐blink conditions, or for the various flow rates (p > 0.05). All tested groups and lenses showed a burst release within the first 4.5 h and rapidly plateaued thereafter. The current study demonstrates that releasable PVA (whether through uptake or through being inherently available from the material) is loosely bound on hydrogel lenses, and the majority is released within 4.5 h. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 107B: 1662–1668, 2019.
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Affiliation(s)
- Chau-Minh Phan
- Centre for Ocular Research & Education (CORE) - formerly Centre for Contact Lens Research (CCLR), School of Optometry and Vision Science, University of Waterloo, Waterloo, Ontario, N2L 3G1, Canada
| | - Hendrik Walther
- Centre for Ocular Research & Education (CORE) - formerly Centre for Contact Lens Research (CCLR), School of Optometry and Vision Science, University of Waterloo, Waterloo, Ontario, N2L 3G1, Canada
| | | | - Charis Lau
- Johnson & Johnson Vision, Inc, Jacksonville, Florida
| | | | - Lakshman Nagapatnam Subbaraman
- Centre for Ocular Research & Education (CORE) - formerly Centre for Contact Lens Research (CCLR), School of Optometry and Vision Science, University of Waterloo, Waterloo, Ontario, N2L 3G1, Canada
| | - Lyndon Jones
- Centre for Ocular Research & Education (CORE) - formerly Centre for Contact Lens Research (CCLR), School of Optometry and Vision Science, University of Waterloo, Waterloo, Ontario, N2L 3G1, Canada
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24
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Lim SH, Kathuria H, Tan JJY, Kang L. 3D printed drug delivery and testing systems - a passing fad or the future? Adv Drug Deliv Rev 2018; 132:139-168. [PMID: 29778901 DOI: 10.1016/j.addr.2018.05.006] [Citation(s) in RCA: 130] [Impact Index Per Article: 21.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2017] [Revised: 04/12/2018] [Accepted: 05/12/2018] [Indexed: 12/23/2022]
Abstract
The US Food and Drug Administration approval of the first 3D printed tablet in 2015 has ignited growing interest in 3D printing, or additive manufacturing (AM), for drug delivery and testing systems. Beyond just a novel method for rapid prototyping, AM provides key advantages over traditional manufacturing of drug delivery and testing systems. These includes the ability to fabricate complex geometries to achieve variable drug release kinetics; ease of personalising pharmacotherapy for patient and lowering the cost for fabricating personalised dosages. Furthermore, AM allows fabrication of complex and micron-sized tissue scaffolds and models for drug testing systems that closely resemble in vivo conditions. However, there are several limitations such as regulatory concerns that may impede the progression to market. Here, we provide an overview of the advantages of AM drug delivery and testing, as compared to traditional manufacturing techniques. Also, we discuss the key challenges and future directions for AM enabled pharmaceutical applications.
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Affiliation(s)
- Seng Han Lim
- Department of Pharmacy, National University of Singapore, 18 Science Drive 4, Block S4A, Level 3, 117543, Singapore
| | - Himanshu Kathuria
- Department of Pharmacy, National University of Singapore, 18 Science Drive 4, Block S4A, Level 3, 117543, Singapore
| | - Justin Jia Yao Tan
- Department of Pharmacy, National University of Singapore, 18 Science Drive 4, Block S4A, Level 3, 117543, Singapore
| | - Lifeng Kang
- School of Pharmacy, University of Sydney, Pharmacy and Bank Building A15, NSW 2006, Australia.
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25
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Contact lenses with dual drug delivery for the treatment of bacterial conjunctivitis. Int J Pharm 2018; 548:139-150. [PMID: 29960036 DOI: 10.1016/j.ijpharm.2018.06.059] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2018] [Revised: 06/26/2018] [Accepted: 06/26/2018] [Indexed: 12/21/2022]
Abstract
Currently, bacterial conjunctivitis is treated by frequent administration of antibiotic eye drop solutions, which is tedious and patient noncompliant. Contact lenses could be ideal medical devices to sustain the release of ophthalmic drugs, but the incorporation of the latter can alter the optical and physical properties of the lenses. In addition, many contact lens users have reported the pink eye syndrome, making them unsuitable as ocular medical devices. In the present study, we have designed a novel type of lenses containing semi-circular rings loaded with moxifloxacin HCl (a broad spectrum antibiotic) and hyaluronic acid (a comfort agent), respectively, in order to treat bacterial conjunctivitis without altering the critical lens properties. The drug loaded rings were implanted separately within the periphery of the contact lenses using the modified cast moulding technology. The atomic force microscopy report showed an average roughness of 22.27 nm for the implant lens, which was significantly lower in comparison to the marketed Freshlook® (116.27 nm) contact lens. The major amount of moxifloxacin HCl was leached (68.16-74.55%) during the monomer extraction and wet sterilization (autoclave) steps; hence the lenses were terminally sterilized by radiation and packaged under dry condition (dehydrated). The in vitro release data showed release for moxifloxacin HCl and hyaluronic acid up to 96 h. The in vivo drug release studies showed significant improvement [>MIC for Staphylococcus aureus] in the drug residence time in comparison to the eye drop therapy. The in vivo efficacy study in the staphylococcus aureus induced conjunctivitis showed equivalent healing effect with the single implant contact lens in comparison to the frequent high dose eye drop therapy. The study demonstrated the successful application of the implantation technology to co-deliver moxifloxacin HCl and hyaluronic acid from the contact lenses for the extended period of time to treat conjunctivitis.
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26
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A comprehensive review on contact lens for ophthalmic drug delivery. J Control Release 2018; 281:97-118. [PMID: 29782944 DOI: 10.1016/j.jconrel.2018.05.020] [Citation(s) in RCA: 97] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Revised: 05/16/2018] [Accepted: 05/17/2018] [Indexed: 12/18/2022]
Abstract
With the prevalence of electronic devices and an aging population, the number of people affected with eye disease is increasing year by year. In spite of a large number of eye drops on the market, most of them do not perform sufficiently, due to rapid clearance mechanisms and ocular barriers. To enhance drug delivery to the eye, a number of novel formulations for ocular diseases have been investigated over recent decades, aiming to increase drug retention and permeation while also allowing for sustained drug release over prolonged periods. The contact lens, initially used to correct visual acuity and beautify female eyes, is one such novel formulation with outstanding potential. Recently, contact lenses have been extensively used for ocular drug delivery to enhance ocular bioavailability and reduce side effects, and are particularly suitable for the treatment of chronic diseases, and thus are of interest to ophthalmic scientists. This review summarizes contact lens classification, methods of preparation, strategies for integrating drugs into lenses, in vitro and in vivo studies, and clinical applications. This review also discusses the current state of ocular drug therapy and provides an outlook for future therapeutic opportunities in the field of ocular drug delivery.
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Phan CM, Weber S, Mueller J, Yee A, Jones L. A Rapid Extraction Method to Quantify Drug Uptake in Contact Lenses. Transl Vis Sci Technol 2018; 7:11. [PMID: 29600119 PMCID: PMC5868858 DOI: 10.1167/tvst.7.2.11] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2017] [Accepted: 02/06/2018] [Indexed: 11/29/2022] Open
Abstract
Purpose To develop a simple extraction procedure to quantify the uptake of four topical ocular pharmaceutical drugs into contact lenses (CLs). Methods Four silicone hydrogel (SH) CLs (balafilcon A, senofilcon A, lotrafilcon B, comfilcon B) and four conventional hydrogel (CH) CLs (nesofilcon A, hilafilcon B, nelfilcon A, etafilcon A) were evaluated. The drugs studied were natamycin, moxifloxacin, timolol maleate, and ketotifen fumarate. For drug incubation, three CLs of each type were placed in 1 mL of 1 mg/mL drug-loading solution for 24 hours. The lenses were then extracted in 2 mL methanol for 2 hours. This process was repeated to obtain a total of three extraction cycles. Detection of natamycin, moxifloxacin, ketotifen fumarate, and timolol maleate were measured by absorbance at 305, 287, 297, and 295 nm, respectively. Results The majority of the drugs were extracted after the first extraction cycle (P < 0.001). For moxifloxacin and timolol, CH CLs had higher drug uptake than SH CLs (P < 0.05). There were no differences in drug uptake between CH CLs and SH CLs for natamycin and ketotifen (P > 0.05). Conclusions This study provides a simple approach to determine drug uptake into CLs. This method can also be modified, such as changing the extraction time, extraction cycles, or extraction solvent to better suit other drugs and CL combinations. Translational Relevance There is considerable interest in using CLs for ocular drug delivery. Accurately quantifying drug uptake on CLs has been a challenge. Hence, this study provides a simple method to quantify drug uptake in CLs.
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Affiliation(s)
- Chau-Minh Phan
- Centre for Ocular Research and Education, School of Optometry and Vision Science, University of Waterloo, Waterloo, Ontario, Canada
| | - Sarah Weber
- Ernst-Abbe-Hochschule Jena University of Applied Sciences, Jena, Germany
| | - Jennifer Mueller
- Ernst-Abbe-Hochschule Jena University of Applied Sciences, Jena, Germany
| | - Alan Yee
- Centre for Ocular Research and Education, School of Optometry and Vision Science, University of Waterloo, Waterloo, Ontario, Canada
| | - Lyndon Jones
- Centre for Ocular Research and Education, School of Optometry and Vision Science, University of Waterloo, Waterloo, Ontario, Canada
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Prina E, Mistry P, Sidney LE, Yang J, Wildman RD, Bertolin M, Breda C, Ferrari B, Barbaro V, Hopkinson A, Dua HS, Ferrari S, Rose FRAJ. 3D Microfabricated Scaffolds and Microfluidic Devices for Ocular Surface Replacement: a Review. Stem Cell Rev Rep 2018; 13:430-441. [PMID: 28573367 DOI: 10.1007/s12015-017-9740-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
In recent years, there has been increased research interest in generating corneal substitutes, either for use in the clinic or as in vitro corneal models. The advancement of 3D microfabrication technologies has allowed the reconstruction of the native microarchitecture that controls epithelial cell adhesion, migration and differentiation. In addition, such technology has allowed the inclusion of a dynamic fluid flow that better mimics the physiology of the native cornea. We review the latest innovative products in development in this field, from 3D microfabricated hydrogels to microfluidic devices.
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Affiliation(s)
- Elisabetta Prina
- Division of Regenerative Medicine and Cellular Therapies, School of Pharmacy, Centre for Biomolecular Sciences, University of Nottingham, Nottingham, UK
| | - Pritesh Mistry
- Division of Regenerative Medicine and Cellular Therapies, School of Pharmacy, Centre for Biomolecular Sciences, University of Nottingham, Nottingham, UK
| | - Laura E Sidney
- Academic Ophthalmology, Division of Clinical Neuroscience, University of Nottingham, Nottingham, UK
| | - Jing Yang
- Division of Regenerative Medicine and Cellular Therapies, School of Pharmacy, Centre for Biomolecular Sciences, University of Nottingham, Nottingham, UK
| | - Ricky D Wildman
- Faculty of Engineering, University of Nottingham, Nottingham, UK
| | - Marina Bertolin
- Fondazione Banca degli Occhi del Veneto, c/o Padiglione G. Rama - Via Paccagnella 11, 30174 Zelarino, Venice, Italy
| | - Claudia Breda
- Fondazione Banca degli Occhi del Veneto, c/o Padiglione G. Rama - Via Paccagnella 11, 30174 Zelarino, Venice, Italy
| | - Barbara Ferrari
- Fondazione Banca degli Occhi del Veneto, c/o Padiglione G. Rama - Via Paccagnella 11, 30174 Zelarino, Venice, Italy
| | - Vanessa Barbaro
- Fondazione Banca degli Occhi del Veneto, c/o Padiglione G. Rama - Via Paccagnella 11, 30174 Zelarino, Venice, Italy
| | - Andrew Hopkinson
- Academic Ophthalmology, Division of Clinical Neuroscience, University of Nottingham, Nottingham, UK
| | - Harminder S Dua
- Academic Ophthalmology, Division of Clinical Neuroscience, University of Nottingham, Nottingham, UK
| | - Stefano Ferrari
- Fondazione Banca degli Occhi del Veneto, c/o Padiglione G. Rama - Via Paccagnella 11, 30174 Zelarino, Venice, Italy.
| | - Felicity R A J Rose
- Division of Regenerative Medicine and Cellular Therapies, School of Pharmacy, Centre for Biomolecular Sciences, University of Nottingham, Nottingham, UK
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Hui A. Contact lenses for ophthalmic drug delivery. Clin Exp Optom 2018; 100:494-512. [PMID: 28940532 DOI: 10.1111/cxo.12592] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Revised: 07/03/2017] [Accepted: 07/03/2017] [Indexed: 01/28/2023] Open
Abstract
Contact lenses as a means to deliver pharmaceuticals to the eye have seen a significant increase in research interest in the past few years. This review will detail the in vitro experiments which have investigated use of these contact lenses in the context of the desired pharmacological treatment goals in the management of infectious, inflammatory, allergic and glaucomatous diseases of the eye. The techniques researchers have employed to modify and tailor drug release rates from these materials, including the use of vitamin E diffusion barriers, modified ionicity, molecular imprinting and incorporation of drug reservoirs, will be discussed, as well as their impact on drug release kinetics. Finally, the demonstration of the feasibility of these materials when applied in vivo in animal models as well as in humans with and without disease will be presented and their results discussed relating to their implications for the future of the field.
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Affiliation(s)
- Alex Hui
- School of Optometry and Vision Science, The University of New South Wales, Sydney, New South Wales, Australia
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30
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Lim WS, Chen K, Chong TW, Xiong GM, Birch WR, Pan J, Lee BH, Er PS, Salvekar AV, Venkatraman SS, Huang Y. A bilayer swellable drug-eluting ureteric stent: Localized drug delivery to treat urothelial diseases. Biomaterials 2018; 165:25-38. [PMID: 29501967 DOI: 10.1016/j.biomaterials.2018.02.035] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2017] [Revised: 02/14/2018] [Accepted: 02/18/2018] [Indexed: 10/18/2022]
Abstract
A bilayer swellable drug-eluting ureteric stent (BSDEUS) is engineered and implemented, as a sustained drug delivery platform technology that enhances localized drug delivery to the highly impermeable urothelium, for the treatment of urothelial diseases such as strictures and carcinomas. On deployment, the device swells to co-apt with the ureteric wall and ensure drug availability to these tissues. BSDEUS consists of a stent spray-coated with a polymeric drug containing polylactic acid-co-caprolactone (PLC) layer which is overlaid by a swellable polyethylene glycol diacrylate (PEGDA) based hydrogel. In-vitro quantification of released drug demonstrated a tunable time-profile, indicating sustained delivery over 1-month. The PEGDA hydrogel overlayer enhanced drug release and transport into explanted porcine ureteric tissues ex-vivo, under a simulated dynamic fluid flow. A preliminary pilot in-vivo feasibility study, in a porcine model, demonstrated that the swollen hydrogel co-apts with the urothelium and thus enables localized drug delivery to the target tissue section. Kidney functions remained unaffected and device did not result in either hydronephrosis or systemic toxicity. This successful engineering of a bilayer coated stent prototype, demonstrates its feasibility, thus offering a unique solution for drug-based urological therapy.
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Affiliation(s)
- Wei Shan Lim
- School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639798, Singapore; Institute of Materials Research and Engineering, Agency for Science, Technology and Research (A*STAR), 2 Fusionopolis Way Innovis, Singapore, 138634, Singapore; Sino-Singapore International Joint Research Institute, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639798, Singapore.
| | - Kenneth Chen
- Department of Urology, Singapore General Hospital, 20 College Road, Singapore, 169856, Singapore.
| | - Tsung Wen Chong
- Department of Urology, Singapore General Hospital, 20 College Road, Singapore, 169856, Singapore
| | - Gordon Minru Xiong
- School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639798, Singapore
| | - William R Birch
- Institute of Materials Research and Engineering, Agency for Science, Technology and Research (A*STAR), 2 Fusionopolis Way Innovis, Singapore, 138634, Singapore
| | - Jisheng Pan
- Institute of Materials Research and Engineering, Agency for Science, Technology and Research (A*STAR), 2 Fusionopolis Way Innovis, Singapore, 138634, Singapore
| | - Bae Hoon Lee
- School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639798, Singapore; School of Biomedical Engineering, School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, Wenzhou, 325027, China; Wenzhou Institute of Biomaterials and Engineering, CNITECH, CAS, Wenzhou, 325001, China
| | - Pei Shan Er
- School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639798, Singapore
| | - Abhijit Vijay Salvekar
- School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639798, Singapore
| | - Subbu S Venkatraman
- School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639798, Singapore; Sino-Singapore International Joint Research Institute, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639798, Singapore.
| | - Yingying Huang
- School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639798, Singapore; Sino-Singapore International Joint Research Institute, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639798, Singapore.
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Thermosensitive hydrogel as an in situ gelling antimicrobial ocular dressing. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2017; 78:203-209. [DOI: 10.1016/j.msec.2017.04.065] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2017] [Revised: 04/07/2017] [Accepted: 04/12/2017] [Indexed: 01/12/2023]
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Sharma A, Taniguchi J. Review: Emerging strategies for antimicrobial drug delivery to the ocular surface: Implications for infectious keratitis. Ocul Surf 2017; 15:670-679. [PMID: 28602948 DOI: 10.1016/j.jtos.2017.06.001] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Revised: 04/06/2017] [Accepted: 06/02/2017] [Indexed: 12/27/2022]
Abstract
Infectious keratitis is a medical emergency that can cause severe visual morbidity if not treated promptly. Depending upon the causative microorganism, effective management of infectious keratitis requires frequent application of antibacterial, antifungal, or antiviral eye drops, which may have low bioavailability, undesirable side effects, and poor patient compliance. Ocular formulations of antimicrobials that can increase corneal permeation and provide extended presence on ocular surface are being developed. Such formulations include nanoparticles, mucoadhesives, in situ forming hydrogels, and contact lenses. Testing of these formulations in in vitro models and ex vivo excised corneas, and in vivo rabbit testing have demonstrated increased bioavailability and extended presence on the cornea. Many of these formulations have also demonstrated success in treating infectious keratitis in animal models. However, the majority of studies have evaluated fluoroquinolone antibacterials, and more studies are needed to test the delivery of antifungal drugs. Moreover, additional efficacy data in animal models and future studies in humans to determine the duration of inhibitory concentrations of these antimicrobials in tear fluid will be required to prove the effectiveness of these formulations for clinical management of infectious keratitis.
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Affiliation(s)
- Ajay Sharma
- Department of Biomedical and Pharmaceutical Sciences, Chapman University School of Pharmacy, Chapman University, Irvine, CA, USA.
| | - Jonathan Taniguchi
- Department of Biomedical and Pharmaceutical Sciences, Chapman University School of Pharmacy, Chapman University, Irvine, CA, USA
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Fernández-Ferreiro A, Silva-Rodríguez J, Otero-Espinar FJ, González-Barcia M, Lamas MJ, Ruibal A, Luaces-Rodríguez A, Vieites-Prado A, Lema I, Herranz M, Gómez-Lado N, Blanco-Mendez J, Gil-Martínez M, Pardo M, Moscoso A, Cortes J, Sánchez-Martínez M, Pardo-Montero J, Aguiar P. In vivo eye surface residence determination by high-resolution scintigraphy of a novel ion-sensitive hydrogel based on gellan gum and kappa-carrageenan. Eur J Pharm Biopharm 2017; 114:317-323. [DOI: 10.1016/j.ejpb.2017.01.023] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2016] [Revised: 01/12/2017] [Accepted: 01/17/2017] [Indexed: 02/02/2023]
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Extended Ciprofloxacin Release Using Vitamin E Diffusion Barrier From Commercial Silicone-Based Soft Contact Lenses. Eye Contact Lens 2017; 43:103-109. [DOI: 10.1097/icl.0000000000000245] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Phan CM, Bajgrowicz-Cieslak M, Subbaraman LN, Jones L. Release of Moxifloxacin from Contact Lenses Using an In Vitro Eye Model: Impact of Artificial Tear Fluid Composition and Mechanical Rubbing. Transl Vis Sci Technol 2016; 5:3. [PMID: 27847690 PMCID: PMC5106195 DOI: 10.1167/tvst.5.6.3] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2016] [Accepted: 09/10/2016] [Indexed: 11/24/2022] Open
Abstract
PURPOSE The aim of this study was to evaluate and compare the release of moxifloxacin from a variety of daily disposable (DD) contact lenses (CLs) under various conditions using a novel in vitro eye model. METHODS Four commercially available DD conventional hydrogel (CH) CLs (nelfilcon A, omafilcon A, etafilcon A, and ocufilcon B) and three silicone hydrogel (SH) CLs (somofilcon A, narafilcon A, and delefilcon A) were evaluated. These lenses were incubated in moxifloxacin for 24 hours. The release of the drug was measured using a novel in vitro model in three experimental conditions: (1) phosphate buffered saline (PBS); (2) artificial tear solution (ATS) containing a variety of proteins and lipids; and (3) ATS with mechanical rubbing produced by the device. RESULTS Overall, CH CLs had a higher drug release than SH CLs (P < 0.05) under all conditions. Typically, a higher drug release was observed in PBS than ATS (P < 0.05). For CH, drug release was found to be higher in ATS with rubbing than PBS or ATS (P < 0.05). For most lens types, ATS with rubbing produced higher drug release than ATS alone (P < 0.05). Generally, the release kinetics for all conditions were sustained over the 24-hour testing period, and no burst release was observed (P < 0.05). CONCLUSIONS Moxifloxacin release from a CL into ATS is lower when compared to release into PBS. When mechanical rubbing is introduced, the amount of drugs released is increased. TRANSLATIONAL RELEVANCE Results suggest that sophisticated in vitro models are necessary to adequately model on-eye drug release from CL materials.
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Affiliation(s)
- Chau-Minh Phan
- Centre for Contact Lens Research, School of Optometry and Vision Science, Waterloo, Ontario, Canada
| | - Magdalena Bajgrowicz-Cieslak
- Department of Mechanics, Material Science and Engineering, Wroclaw University of Science and Technology, Wroclaw, Poland
| | - Lakshman N. Subbaraman
- Centre for Contact Lens Research, School of Optometry and Vision Science, Waterloo, Ontario, Canada
| | - Lyndon Jones
- Centre for Contact Lens Research, School of Optometry and Vision Science, Waterloo, Ontario, Canada
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Pimenta AFR, Valente A, Pereira JMC, Pereira JCF, Filipe HP, Mata JLG, Colaço R, Saramago B, Serro AP. Simulation of the hydrodynamic conditions of the eye to better reproduce the drug release from hydrogel contact lenses: experiments and modeling. Drug Deliv Transl Res 2016; 6:755-762. [DOI: 10.1007/s13346-016-0303-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Phan CM, Walther H, Gao H, Rossy J, Subbaraman LN, Jones L. Development of an In Vitro Ocular Platform to Test Contact Lenses. J Vis Exp 2016:e53907. [PMID: 27078088 DOI: 10.3791/53907] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Currently, in vitro evaluations of contact lenses (CLs) for drug delivery are typically performed in large volume vials, which fail to mimic physiological tear volumes. 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.
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Affiliation(s)
- Chau-Minh Phan
- School of Optometry and Vision Science, University of Waterloo;
| | - Hendrik Walther
- School of Optometry and Vision Science, University of Waterloo
| | | | - Jordan Rossy
- School of Optometry and Vision Science, University of Waterloo
| | | | - Lyndon Jones
- School of Optometry and Vision Science, University of Waterloo
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