Peg 4000

UC781 was supplied by CONRAD. PVA, Polyethylene glycol (PEG) 400, PEG 600, glycerin, and propylene glycol were purchased from Spectrum (New Brunswick, NJ). PEG 4000 was supplied by the Dow Chemical Company (Midland, MI), and hydroxypropyl methylcellulose (HPMC K4M; Methocel^®) was supplied by Colorcon (Harleysville, PA). Woman's Condom samples were provided by PATH (manufactured by Dahua). A MilliQ (Millipore; Milford, MA) water filtration system operating at 18.2 MΩcm was used for water.

Custom synthesis of EFdA was carried out by Life Chemicals (Burlington, ON, Canada) and CSIC was synthesized by Dalton Laboratories (Toronto, ON, Canada). The drugs were >95% pure as assessed by HPLC/MS and NMR according to the suppliers. DMSO, McCoy’s 5A medium and fetal bovine serum (FBS) were obtained from Fisher Scientific (Pittsburgh, PA, US). PBS (pH 7.4) and penicillin-streptomycin were purchased from Mediatech Inc (Manassas, VA, US). Polyvinyl alcohol (PVA), Pullulan, (2-hydroxypropyl)-β-cyclodextrin (HP-β-CD), glycerin and PEG 400 were purchased from Spectrum (Gardena, CA, US). PEG 4000 and hydroxypropyl methyl cellulose E5 (HPMC E5) were obtained from Dow Chemical Company (Midland, MI, US). MTT, cremophor RH 40, bovine serum albumin (BSA) and methyl-β-cyclodextrin (M-β-CD) were purchased from Sigma-Aldrich (St. Louis, MO, USA). Pluronic F127 was kindly provided by BASF Ltd. (NJ, US). All other chemicals were analytical grade. Ultrapure water was obtained in-house from a MilliQ water purification system.