Hpmc e5

Darunavir Ethanolate, Ritonavir, and Atazanavir Sulphate were received as a gift sample from Ranbaxy Research Laboratory (Gurgaon, India). Soluplus, Kolliphor TPGS (d-alpha-tocopheryl polyethylene glycol 1000 succinate), and Poloxamer 188 were obtained from BASF (Ludwigshafen, Germany). PVP K30 (Polyvinylpyrrolidone K30) was obtained from ISP (New Jersey, USA) and HPMC E5 (hydroxypropyl methylcellulose) from Dow Chemical Company (Michigan, USA). Diethyl ether and ethanol were obtained from Merck (Mumbai, India). SIF (Simulated Intestinal Fluid) powder was from Phares AG (Basel, Switzerland). Other chemicals and reagents used were from SD Fine Chemicals, Ltd. (Mumbai, India), and Qualigens Fine Chemical (Mumbai, India) and were of analytical grade. All drug solutions and buffer solutions were freshly prepared before use.

The feedstock solution was prepared by dissolving either a 1/9/0.5 or 1/3/0.15 weight ratio of FLU (Shaanxi Hanjiang Pharmaceutical Group, Hanzhong City, China)/polymer/Vitamin E d-α-tocopheryl polyethylene glycol 1000 succinate (TPGS; Barentz NV, Zaventem, Belgium) in 1/9 (wt./wt.) 98%-100% formic acid (FA; Merck, Overijse, Belgium)/dichloromethane (DCM; Merck). The selected polymers were either hydroxypropylmethylcellulose (HPMC E5; Dow Chemical, Terneuzen, The Netherlands) or polyvinylpyrrolidone-vinyl acetate 64 (PVP VA 64; Kollidon^®64, BASF, Ludwigshaven, Germany). A Büchi 290 (Flawil, Switzerland) equipped with an inert loop was used to spray dry in closed loop conditions with an inlet and outlet temperature of 65°C and 45°C, respectively, and a spray rate of 8 g/min under nitrogen flow. The damp powder was removed from the collector and dried ≤20 h in a vacuum oven (Heraeus, Liederkerke, Belgium) set to 45°C and 200 mbar under nitrogen flow. To investigate the influence of drying time, the 1/3/0.15, FLU/HPMC E5/Vit. E TPGS was also dried for 5 days under the same conditions.