Pvp k 29 32

Albumin from chicken egg white lyophilised powder (referred as OVAlbumin, OVA, lyophilised powder, ≥ 98%), bovine serum albumin (BSA), phosphate-buffered saline (PBS, pH = 7.4) tablets, sodium chloride (NaCl) and PVA (31–50 kDa) were purchased from Sigma-Aldrich (Dorset, UK). HA (sodium hyaluronate, 200–400 kDa) was obtained from Kewpie Corporation (Tokyo, Japan). PVP K-29/32 (58 kDa) and K-90 (360 kDa) were purchased from Ashland (Kidderminster, UK). Glycerol, AnalaR NORMAPUR, 99.5% was obtained from VWR International (Leicestershire, UK). All other chemicals were of analytical reagent grade.

TAF (also known as GS-7340) was provided by Gilead Sciences, Inc. TAF and TFV and their stable isotopically labelled (SIL) internal standards (TFV-d6 and TAF-d5) were obtained from Toronto Research Chemicals (Canada). Poly(vinylpyrrolidone) (PVP K29-32; and PVP K90) was provided by Ashland (Kidderminster, UK). Poly(vinyl alcohol) (PVA 9–10 ​kDa) and solvents methanol ≥99.9%, dimethyl sulfoxide (DMSO), tetrahydrofuran (THF) inhibitor-free ≥ 99.9% and acetonitrile (ACN) ​≥ ​99.9% (all HPLC grade), ammonium acetate ≥98%, and Acetic acid ≥99.7% were purchased from Sigma-Aldrich, St. Louis, USA. Two different types of poly(d,l-lactide-co-glycolide) (PLGA) were used, a low viscosity PLGA, Purasorb® PDLG 7502 with a lactide:glycolide ratio of 75:25 and ester end (Purac®, Corbion, Netherlands) (LV-PLGA) and a high viscosity PLGA with a lactide:glycolide ratio of 75:25 and ester end (Viatel® DLG 7503 ​E) (HV-PLGA). Both PLGAs were a donation from Ashland (Kidderminster, UK). All other reagents used in this work were of analytical grade and purchased from Sigma-Aldrich. Elga purified water was used in all cases (Purelab option® Elga LabWater, High Wycombe, UK).