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Ranjani Nellore

Publications and source records attributed to Ranjani Nellore.

2 recordsLinked to original sources

High-performance liquid chromatography method development and validation for simultaneous determination of five model compounds, antipyrine, metoprolol, ketoprofen, furosemide and phenol red, as a tool for the standardization of rat in situ intestinal permeability studies using timed wavelength detection.

A simple, precise, accurate and rugged reversed-phase high-performance liquid chromatography (HPLC) method has been developed and validated for the simultaneous determination of five permeability model compounds, viz. antipyrine, metoprolol, ketoprofen, furosemide and phenol red. The method was intended to standardize rat in situ single-pass intestinal perfusion studies to assess the intestinal permeability of drugs in the market as well as new chemical entities. Optimum resolution was achieved by gradient elution on a Symmetry Shield C-18 analytical column with the mobile phase consisting of a mixture of aqueous potassium dihydrogen orthophosphate (pH 5.5; 0.01 m) and methanol at a flow rate of 1.5 mL/min. The retention times of antipyrine, metoprolol, ketoprofen, phenol red and furosemide were about 9, 12, 13, 16 and 17 min, respectively. Data acquisition was carried out using a photo diode array detector in the wavelength range 210-600 nm. Extraction of chromatograms was carried out by timed wavelength. Data obtained in all studies indicated that the method was suitable for the intended purpose. The validated method was found to be linear and precise in the working range. Suitability of storage under various conditions and freeze/thaw impact at cold temperature were established to ensure complete sample recovery without any stability issues. Recovery very close to the spiked amounts indicated that the method was highly accurate and suitable for use on routine basis.

Animals↗

Pre-clinical and clinical evaluation of solution and soft gelatin capsule formulations for a BCS class 3 compound with atypical physicochemical properties.

R1481 is a sub-type selective muscarinic receptor antagonist with the potential treatment of overactive bladder. R1481 presents two challenges for drug development. The first is the viscous semi-solid nature of the active pharmaceutical ingredient (API). The second challenge is the poor oral bioavailability of this water soluble, metabolically stable compound due to low intestinal permeability, and the P-glycoprotein (P-gp) efflux mechanism. Vitamin E TPGS is reported by others to enhance bioavailability by increasing the solubility of active compounds and by inhibiting P-gp in the intestine. In this report, compatibility of R1481 in Capmul MCM-based formulations with and without vitamin E TPGS is summarized. Review of accelerated stability studies of oral formulations led to the identification of a soft gelatin capsule formulation using neat Capmul MCM as an acceptable formulation for Phase 1 clinical studies. Soft gelatin capsules (5 mg strength) were manufactured with and without the addition of vitamin E TPGS. Clinical data show that vitamin E TPGS does not improve systemic exposure of R1481 in humans.

Adult↗