The Effect of Photoinitiator Concentration on the Physicochemical Properties of Hydrogel Contact Lenses

Abstract:

Hydrogel soft contact lenses have been investigated as delivery systems for ophthalmic drug products in response to the need for more efficient ophthalmic drug delivery systems. Ocular drugs delivered via eye drops have a low residence time in the eye resulting in as low as 5% bioavailability of the therapeutic agent. This study investigates the effect of varying concentrations of the photoinitiator diphenyl (2,4,6-trimethylbenzoyl)-phosphine oxide (TPO) on the physicochemical properties of hydrogel soft contact lenses for ophthalmic drug delivery purposes. Contact lens samples were synthesised via photopolymerisation with a range of initiator concentration. Gel fraction and swelling results indicated that increasing the photoinitiator concentration increased the efficiency of the gel network and reduced the water content of contact lens samples. Fourier transform infra-red spectroscopy (FTIR) analysis was employed to confirm polymerisation of the lenses and also indicated the presence of residual photoinitiator in lenses with higher TPO concentrations.

• Periodical: Applied Mechanics and Materials (Volume 679)
• Pages: 118-127
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.679.118
• Online since: October 2014
• Authors: Deirdre M. McElroy, Luke M. Geever, Clement L. Higginbotham, Sinead M. Devery
• Keywords: Contact Lenses, Hydrogels, Hydroxyethyl Methacrylate, N-Vinyl-2-pyrrolidinone, Photoinitiator

References

[1] L. Xinming, C. Yingde, A. W. Lloyd, S. V. Mikhalovsky, S. R. Sandeman, C. A. Howel, L. Liewen, Polymeric hydrogels for novel contact lens-based ophthalmic drug delivery systems: A review: Contact Lens and Anterior Eye (2008) v. 31, pp.57-64.

DOI: 10.1016/j.clae.2007.09.002

[2] H. Hiratani, C. Alvarez-Lorenzo, The nature of backbone monomers determines the performance of imprinted soft contact lenses as timolol drug delivery systems: Biomaterials (2004) v. 25, pp.1105-1113.

DOI: 10.1016/s0142-9612(03)00622-7

[3] H.J. Jung, A. Chauhan, Temperature sensitive contact lenses for triggered ophthalmic drug delivery: Biomaterials (2012) v. 33, pp.2289-2300.

DOI: 10.1016/j.biomaterials.2011.10.076

[4] E.M. del Amo, A. Urtti, Current and future ophthalmic drug delivery systems: A shift to the posterior segment: Drug Discovery Today (2008) v. 13, pp.135-143.

DOI: 10.1016/j.drudis.2007.11.002

[5] C. -C., Li, A. Chauhan, Modeling ophthalmic drug delivery by soaked contact lenses: Ind. Eng. Chem. Res. (2006) v. 45, pp.3718-3734.

DOI: 10.1021/ie0507934

[6] C. -C. Peng, M. T. Burke, B. E. Carbia, C. Plummer, A. Chauhan, Extended drug delivery by contact lenses for glaucoma therapy: Journal of Controlled Release (2012) v. 162, pp.152-158.

DOI: 10.1016/j.jconrel.2012.06.017

[7] X. -Z. Zhang, D. -Q. Wu, and C. -C. Chu, Synthesis, characterization and controlled drug release of thermosensitive IPN-PNIPAAm hydrogels: Biomaterials (2004) v. 25, pp.3793-3805.

DOI: 10.1016/j.biomaterials.2003.10.065

[8] R. C. Peterson, J. S. Wolffsohn, J. Nick, L. Winterton, J. Lally, Clinical performance of daily disposable soft contact lenses using sustained release technology: Contact Lens and Anterior Eye (2006) v. 29, pp.127-134.

DOI: 10.1016/j.clae.2006.03.004

[9] H. Gupta, M. Aqil, Contact lenses in ocular therapeutics: Drug Discovery Today (2012) v. 17, pp.522-527.

DOI: 10.1016/j.drudis.2012.01.014

[10] R. Garhwal, S. F. Shady, E. J. Ellis, J. Y. Ellis, C. D. Leahy, S. P. McCarthy, K. S. Crawford, P. Gaines, Sustained Ocular Delivery of Ciprofloxacin Using Nanospheres and Conventional Contact Lens Materials: Investigative Ophthalmology & Visual Science (2012).

DOI: 10.1167/iovs.11-8215

[11] H.J. Jung, M. Abou-Jaoude, B. E. Carbia, C. Plummer, A. Chauhan, Glaucoma therapy by extended release of timolol from nanoparticle loaded silicone-hydrogel contact lenses: Journal of Controlled Release (2013) v. 165, pp.82-89.

DOI: 10.1016/j.jconrel.2012.10.010

[12] H. Hiratani, C. Alvarez-Lorenzo, Timolol uptake and release by imprinted soft contact lenses made of N, N-diethylacrylamide and methacrylic acid: Journal of Controlled Release (2002) v. 83, pp.223-230.

DOI: 10.1016/s0168-3659(02)00213-4

[13] P.C. Nicolson, J. Vogt, Soft contact lens polymers: an evolution, Biomaterials (2001) Dec; 22(24): 3273-83.

DOI: 10.1016/s0142-9612(01)00165-x

[14] M. Hamidi, A. Azadi, P. Rafiei, Hydrogel nanoparticles in drug delivery: Advanced Drug Delivery Reviews (2008) v. 60, pp.1638-1649.

DOI: 10.1016/j.addr.2008.08.002

[15] P. Chhabra, R. Gupta, G. Suri, M. Tyagi, G. Seshadri, S. Sabharwal, U. K. Niyogi, R.K. Khandal, Studies on Development of Polymeric Materials Using Gamma Irradiation for Contact and Intraocular Lenses: International Journal of Polymer Science (2009).

DOI: 10.1155/2009/906904

[16] F. Yañez, A. Concheiro, C. Alvarez-Lorenzo, Macromolecule release and smoothness of semi-interpenetrating PVP–pHEMA networks for comfortable soft contact lenses: European Journal of Pharmaceutics and Biopharmaceutics (2008) v. 69, pp.1094-1103.

DOI: 10.1016/j.ejpb.2008.01.023

[17] M. Paul, H.B. Park, B. D Freeman, A. Roy, J.E. McGrath, J.S. Riffle, Synthesis and crosslinking of partially disulfonated poly(arylene ether sulfone) random copolymers as candidates for chlorine resistant reverse osmosis membranes, Polymer 49 (2008).

DOI: 10.1016/j.polymer.2008.02.039

[18] C. Soykan, A. Delibas, and R. Coskun, Copolymers of N-(4-bromophenyl)-2-methacrylamide with 2-hydroxyethyl methacrylate: eXPRESS Polymer Letters (2007) v. 1, pp.594-603.

DOI: 10.3144/expresspolymlett.2007.81

[19] S.L.J. Tomić, M. M. Mićić, J. M. Filipović, E. H. Suljovrujić, Synthesis, characterization and controlled release of cephalexin drug from smart poly(2-hydroxyethyl methacrylate/poly(alkylene glycol)(meth)acrylates hydrogels: Chemical Engineering Journal (2010).

DOI: 10.1016/j.cej.2010.03.089

[20] European Commission Regulation No 1272/2008 of 16 December (2008).

[21] F. Fornasiero, M. Ung, C. J. Radke, J. M. Prausnitz, Glass-transition temperatures for soft-contact-lens materials. Dependence on water content: Polymer (2005) v. 46, pp.4845-4852.

DOI: 10.1016/j.polymer.2005.03.084

[22] Q. Garrett, B. Laycock, and R. W. Garrett, Hydrogel lens monomer constituents modulate protein sorption: Investigative  Ophthalmology & Visual Science (2000) v. 41, pp.1687-1695.

[23] M.S. Lord, M. H. Stenzel, A. Simmons, and B. K. Milthorpe, The effect of charged groups on protein interactions with poly(HEMA) hydrogels: Biomaterials (2006) v. 27, pp.567-575.

DOI: 10.1016/j.biomaterials.2005.06.010

[24] L. Santos, D. Rodrigues, M. Lira, M. Real Oliveira, R. Oliveira, E. Vilar, J. Azeredo, Bacterial adhesion to worn silicone hydrogel contact lenses.: Optom Vis Sci (2008) v. 85, pp.520-524.

DOI: 10.1097/opx.0b013e31817c92f3