Development and Validation of Chromatographic Methods for Simultaneous Estimation of Aspirin and Pantoprazole Sodium in Pure and Mixture Form.

This technique is employed for the simultaneous quantification of aspirin (ASP) and pantoprazole sodium in both pure powder form and formulations. The high performance liquid chromatography (HPLC) method uses a C-18 column (250 mm × 4.6 mm, 5 µm) with a mobile phase consisting of 0.05 M disodium hydrogen phosphate and methanol in a 40:60% v/v ratio. The flow rate is maintained at 1.0 mL/min. On a layer of silica gel 60F254 with an aluminum backing, the high performance thin layer chromatography (HPTLC) separation was carried out with ethyl acetate and methanol (8: 1.5 v/v) as the mobile phase. With a mean recovery of 100.54% and 99.55% for ASP and PNT, respectively, quantification was accomplished using the HPLC method with UV detection at 286 nm over the concentration range of 0.1-0.6 g/mL for PNT and 0.4-2.4 g/mL for ASP. With a mean recovery of 99.44% and 99.01% for ASP and PNT, respectively, quantification was achieved using the HPTLC method with UV detection at 298 nm over the concentration range of 400-2400 ng/spot for ASP and 100-600 ng/spot for PNT, respectively. The methods can be used for the simultaneous determination of ASP and PNT in pure powder form and formulations as they are simple, accurate and sensitive.

Simultaneous Quantitative Analysis of Six Proton-Pump Inhibitors with a Single Marker and Evaluation of Stability of Investigated Drugs in Polypropylene Syringes for Continuous Infusion Use.

OBJECTIVE: We developed and validated a simple, convenient and reproducible method for simultaneous estimation of six proton-pump inhibitors (PPIs), omeprazole (OPZ), esomeprazole (EOPZ), lansoprazole (LPZ), pantoprazole (PPZ), rabeprazole (RPZ) and ilaprazole (IPZ) in pharmaceutical dosage forms by a single marker. Meanwhile, the stability of the cited PPIs in 0.9% sodium chloride injection stored in polypropylene syringes up to 48 hours for continuous infusion use was investigated. MATERIALS AND METHODS: The chromatographic separation was achieved on an InterSustain® C18 column (150 × 4.6 mm, 5 µm). The isocratic mobile phase made up of 0.05 M potassium dihydrogen phosphate buffer (pH 4.0): acetonitrile (65:35, v/v) was pumped through the column at a temperature maintained at 30°C and a flow rate of 1.0 mL/min. The relative retention time, UV spectral similarity and relative correction factors between OPZ and the other five PPIs were calculated and investigated using the quantitative analysis of multi-components with a single marker (QAMS) method. The stability study examined physical parameters, pH values and drug concentrations of the PPIs mixtures. RESULTS: Under these conditions, all cited PPIs were separated simultaneously at a retention time of 6.0, 7.3, 7.3, 9.9, 12.5 and 13.9 min for RPZ, OPZ, EOPZ, IPZ, PPZ and LPZ, respectively, with a total run time less than 20.0 min. Comparative analysis results indicated that there were no significant differences observed between the QAMS method and the external standard method. The percentage of initial concentration of each PPI gradually decreased during the storage time. CONCLUSION: The proposed method, which is selective, economical and accurate, was applied successfully for determination of the cited PPIs in their respective pharmaceutical dosage forms. Admixtures of OPZ, EOPZ, PPZ, IPZ in 0.9% sodium chloride injection were stable for 24 hours and LPZ, RPZ in 0.9% sodium chloride injection were stable for 8 hours in polypropylene syringes.

A Sensitive, Simple and Direct Determination of Pantoprazole Based on a "Turn off-on" Fluorescence Nanosensor by Using Terbium-1,10-phenanthroline-silver Nanoparticles.

A new sensitive, simple, rapid, reliable and selective fluorometric method for the determination of pantoprazole (PAN) in human plasma and a pharmaceutical formulation has been developed. This technique is based on a quenching effect of silver nanoparticles (AgNPs) on the emission intensity of a fluorescent probe, terbium(III)-1,10-phenantroline (Tb(III)-phen) complex (due to a fluorescence resonance energy transfer (FRET) phenomenon between the Tb(III)-phen complex and AgNPs), and then restoring the fluorescence intensity of the Tb(III)-phen-AgNPs system upon the addition of PAN (turn off-on process). The effects of various factors on the proposed method including time, temperature, pH, order of the addition of various reagents and the concentration of AgNPs were investigated. Under the optimal conditions, a good linear relationship between the enhanced emission intensity of the Tb(III)-phen-AgNPs system and the PAN concentration was observed in the range of (10 - 1000) × 10-8 M. The limit of detection (LOD) and the limit of quantitation (LOQ) were 7.2 × 10-8 and 24.2 × 10-8 M, respectively. Also, the interferences of some common interfering species on the fluorescence intensity of the system were investigated. This simple and sensitive method was successfully applied for the determination of PAN in spiked human plasma samples and in its capsule formulation. The analytical recoveries were in the range of 88.54 - 101.33 and 90.07 - 98.85%, respectively.