Brij 52

BRT was kindly supplied by Orchidia pharmaceutical company, Obour, Egypt. L-α-phosphatidylcholine from soya bean type IV-S (enzymatic), Cholesterol, Brij 52, Dialysis membrane 12,000–14,000 molecular weight cut off were purchased from Sigma-Aldrich Co. (Darmstadt, Germany). Span 60 (Sorbitan monostearate) was purchased from SD fine chemicals, Mumbai, India . Ethyl alcohol (95%), Tween 80, methanol, sodium chloride, sodium bicarbonate, disodium hydrogen phosphate, potassium dihydrogen orthophosphate, and anhydrous calcium chloride were purchased from El Nasr pharmaceutical company (Cairo, Egypt). The market eye drops Alphagan^®P (batch no. 95184) manufactured by Allergan (Allergan Inc., Irvine, CA) was purchased to be used in comparative studies.

Piroxicam (PX) was a kind gift from Medical Union Pharmaceutical (MUP) Co., Egypt. Tween^® 80 (polyethylene sorbitan monooleate), Span^® 80 (Sorbitan monooleate), Brij 52^® (Polyethylene glycol hexadecyl ether, Polyoxyethylene (2) cetyl ether) and cellulose membrane dialysis bag were purchased from Sigma-Aldrich Chemie GmbH, Steinheim, Germany. Freund's complete adjuvant (CFA) was obtained from Difco Laboratories, Detroit, MI, USA. Captex^® GTO was a kind donation from Abitec Corporation, Janesville, USA. Di-methyl sulfoxide (DMSO) was obtained from Merck KGaA, Darmstadt, Germany. Di-sodium hydrogen orthophosphate anhydrous (Minimum Assay Acidimetric 98%), sodium di-hydrogen orthophosphate-1-hydrate (Minimum Assay 98%) and sodium chloride were obtained from ADWIC, Egypt. PURASORB^® PDLG 7502 (75/25 DL-lactide/glycolide copolymer) was a kind gift From Corbion Co., Netherlands. Gelatin was purchased from Alnasr Co., Egypt. Eudragit^® RL 100 (N,N-dimethylmethanamine;2-methylprop-2-enoic acid) was obtained from Evonik Operations GmbH, Germany