Tween 80

Prednisone powder was purchased from Skyrun (Taizhou, China). Microcrystalline Cellulose (Comprecel^® M102 D+) was purchased from Mingtai chemicals (Taoyuan Hsien, Taiwan). Eudragit^® RL 30 D was donated by Rohm Pharma (Darmstadt, Germany). Sodium starch glycolate, talc, magnesium stearate, Tween^® 80 were donated by Aspen Pharmacare (Port Elizabeth, South Africa). Polyethylene Glycol (PEG) 400 was purchased from Merck chemicals (Johannesburg, South Africa). Hydrochlorothiazide was purchased from Skyrun (Taizhou, China). HPLC far UV grade acetonitrile (ROMIL-SpS^™) was purchased from Microsep (Port Elizabeth, South Africa). The HPLC grade water used for analyses was prepared using a Milli-Q^® Academic A10 water purification system (Millipore^®, Bedford, MA, USA), consisting of an Ionex^® ion-exchange cartridge and a quantum EX-ultrapore organex cartridge, which was fitted with a 0.22 μm Millipak^® 40 sterile filter (Millipore^®, Bedford, MA, USA).

EFV was donated by Adcock Ingram^® Limited (Johannesburg, Gauteng, South Africa). Glyceryl monostearate (GM) and Tween^® 80 were purchased from Aspen^® Pharmacare (Port Elizabeth, Eastern Cape, South Africa). Transcutol^® HP (THP) was donated by Gattefossé SAS (Gattefossé SAS, Saint-Priest Cedex, France). Sodium lauryl sulphate (SLS) was purchased from Sigma Aldrich Chemical Co. (Milwaukee, WI, USA). HPLC-grade water was obtained from a Milli-RO^® 15 water purification system (Millipore^®, Bedford, MA, USA).