Methyl trypsin loaded poly(D,L-lactide-coglycolide) nanoparticles for contact lens care.
The need of an enzymatic cleaner for soft contact lens care with an improved ocular safety and stability profile led us to evaluate the use of nanoparticles (NPs) of poly(D,L-lactide-coglycolide) (PLGA) and methyl trypsin (MT). NPs were prepared by double emulsion-solvent evaporation technique. A factorial design was performed to select the lactic acid proportion in the copolymer and conditions of the second sonication. The increment in proportion of lactic acid provided higher particle size results. When the time of second sonication was decreased, the entrapment efficiency (EE) increased. PLGA 50:50 NPs were chosen for further development since PLGA 50:50H NPs settled fast with different particle size in the sediment and PLGA 75:25 NPs led to form aggregates. The addition of glycerol to the NPs provided the highest EE of MT (>90%) while the addition of Tetronic 1304 promoted the fast release of enzyme initially and decreased the zeta potential (zeta) up to neutral values after gamma irradiation. NPs are expected to be effective as a lens care cleaner after 3 days or even longer with a very low quantity of enzyme released. Formulations showed an acceptable irritation ocular tolerance after in vitro HET-CAM test and in vivo Draize test.
Faculty of Pharmacy and Institute of Nanoscience and Nanotechnology, Department of Physical Chemistry, Barcelona, Spain. nuriajr@hotmail.com
N
N
Jimenez
J
J
Galan
A
A
Vallet
M A
MA
Egea
M L
ML
Garcia
D000818:Animals; D002642:Chick Embryo; D049033:Chorioallantoic Membrane / Q000187:drug effects; D018639:Contact Lens Solutions / Q000008:administration & dosage / Q000009:adverse effects / Q000737:chemistry*; D004337:Drug Carriers / Q000008:administration & dosage / Q000009:adverse effects / Q000138:chemical synthesis*; D004339:Drug Compounding / Q000379:methods; D004355:Drug Stability; D004655:Emulsions / Q000008:administration & dosage / Q000737:chemistry; D005123:Eye / Q000187:drug effects; D019344:Lactic Acid / Q000008:administration & dosage / Q000737:chemistry*; D008297:Male; D053758:Nanoparticles / Q000008:administration & dosage / Q000737:chemistry*; D036103:Nanotechnology / Q000379:methods; D010316:Particle Size; D011100:Polyglycolic Acid / Q000008:administration & dosage / Q000737:chemistry*; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011817:Rabbits; D013499:Surface Properties; D014357:Trypsin / Q000008:administration & dosage / Q000009:adverse effects / Q000737:chemistry*
D018639:Contact Lens Solutions; D004337:Drug Carriers; D004655:Emulsions; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid; D014357:Trypsin