Tenofovir4 Case Study

INTRODUCTION: Efavirenz5 (S)-6chloro(cyclopropylethylethynyl-1,4-(trifluoromethyl)-2H-1-benzoxazin-2-one) non-nucleoside reverse transcriptase inhibitor (NNRTI) and is used as part of highly active antiretroviral therapy (HAART) for treatment of human immunodeficiency virus (HIV). Emtricitabine5 is chemically 4-amino-5-fluoro-1-[(2R,5S)-2-(hydroxymethyl)-1,3-oxathiolan-5-yl]-2-(1H)-pyrimidon a nucleoside reverse transcriptase inhibitor (NRTI). The drug works by inhibiting reverse transcriptase, the enzyme that copies HIV RNA into new viral DNA. Tenofovir5 is [{1R)-2-(6-amino-9Hupurin-9-yl-1-methylethoxy} methyl] phosphonic acid. Tenofovir is a nucleoside analog reverse transcriptase inhibitor (NRTI).
Literature survey reveals that chromatographic methods were not reported for related combination dosage form of Efavirenz, Emtricitabine and Tenofovir disoproxil.

Filtered the solution through 0.45 µm nylon filter
Buffer having pH 3.70 used as Mobile phase A and mixture of methanol, acetonitrile and tetrahydrofuran (50: 50: 2 v/v/v) were used as Mobile phase B.
Diluent: Prepared a mixture of buffer and methanol (80: 20 v/v).
Placebo preparation (Placebo I):
Weighed accurately and transferred 255 mg of placebo to a 100 mL volumetric flask. Add 40 mL of methanol and sonicated for 10 mins and add about 30 mL of diluent and again sonicate for 15 mins. Allow to equilibrate at room temperature (RT) and dilute to volume with diluent. Filter the solution through 0.45 µm nylon filter (25 mm) by discarding first few mL of the filtrate.
Placebo containing Emtricitabine (Placebo