American Journal of PharmTech Research AJPTR 2249-3387 undefined AJPTR025391 Estimation of Bosentan Monohydrate in Tablet Dosage Forms by a New RP-HPLC Method Rao T. Nageswara T.B.Patrudu T.B.Patrudu Raghubabu K. Nagachandrudu S. Reddy D. Sreenivasulu3 and and E.G Sreenivasula Department of Engineering Chemistry, Andhra University, Visakhapatnam, AP, India. Department of Engineering Chemistry, GITAM University, Hyderabad, AP, India. SV University, Tirupathi, AP, India. S.K.University, Anantapur, AP, India. 10 01 2012 2 5

A Simple, Sensitive, and rapid reverse phase high performance liquid chromatographic method has been developed for the determination of Bosentan monohydrate in bulk and tablet Dosage Forms. Chromatographic separation was achieved on a Zorbax SB-Phenyl (150×4.6 mm), 3.5 µm make: Aglient column with a 30:70 mixture of 0.02M sodium dihydrogen phosphate and HPLC grade Methanol as mobile phase, detection was at 225 nm, oven temperature is 30°C, injection volume is 20µL, flow rate is 1.5 mL/min and the expected retention of Bosentan monohydrate peak is about 5.2 minutes. Response was a linear function of concentration in the range 2-0.01 µg/mL for Bosentan monohydrate; correlation coefficiencent was 0.9999, respectively.LOD and LOQ for Bosentan monohydrate were found 0.01 µg/mL and 0.03 µg/mL based on signal to noise ratio(S/N). Accuracy (recoveries 90-98%) and reproducibility were found to satisfactory. Key words: Bosentan monohydrate, S/N ratio, RP-HPLC method and validation.

 Bosentan monohydrate S/N ratio RP-HPLC method and validation.