Stability-indicating determination of rebamipide in the presence of its acid degradation products.

Four sensitive and precise stability-indicating methods for the determination of rebamipide (REB) in the presence of its acid-degradation products and in a pharmaceutical formulation were developed and validated. Method A used the first derivative of the ratio spectra (1DD) spectrophotometric method by measuring the peak amplitude at 249.4 nm (maximum) and at 259 nm (minimum), and at the total peak amplitude (from 249.

Validated chromatographic methods for determination of perindopril and amlodipine in pharmaceutical formulation in the presence of their degradation products.

Two specific, sensitive, and precise stability-indicating chromatographic methods have been developed, optimized and validated for determination of perindopril arginin (PER) and amlodipine besylate (AML) in their mixtures and in the presence of their degradation products. The first method was based on thin-layer chromatography (TLC) combined with densitometric determination of the separated bands. Adequate separation was achieved using silica gel 60 F254 TLC plates and ethyl acetate-methanol-toluene-ammonia solution, 33% (6.

Comparative study of 2-hydroxy propyl beta cyclodextrin and calixarene as ionophores in potentiometric ion-selective electrodes for neostigmine bromide.

Three novel neostigmine bromide (NEO) selective electrodes were investigated with 2-nitrophenyl octyl ether as a plasticiser in a polymeric matrix of polyvinyl chloride (PVC). Sensor 1 was fabricated using tetrakis(4-chlorophenyl)borate (TpClPB) as an anionic exchanger without incorporation of an ionophore. Sensor 2 used 2-hydroxy propyl β-cyclodextrin as an ionophore while sensor 3 was constructed using 4-sulfocalix-8-arene as an ionophore.

Stability-indicating spectrophotometric and spectrodensitometric methods for the determination of diacerein in the presence of its degradation product.

Three sensitive, selective, and precise stability-indicating methods for the determination of the novel osteoarthritis drug, diacerein (DIA) in the presence of its alkaline degradation product (active metabolite, rhein) and in pharmaceutical formulation were developed and validated. The first method is a first derivative (D(1) ) spectrophotometric one, which allows the determination of DIA in the presence of its degradate at 322 nm (corresponding to zero crossing of the degradate) over a concentration range of 4-40 µg/mL with mean percentage recovery 100.21 ± 0.

Spectrophotometric and spectrodensitometric methods for the determination of rivastigmine hydrogen tartrate in presence of its degradation product.

Three sensitive, selective and precise stability-indicating methods for the determination of the anti-Alzheimer's drug, rivastigmine hydrogen tartrate (RIV) in the presence of its alkaline degradation product (major metabolite, NAP 226-90) and in pharmaceutical formulation were developed and validated. The first method is a second derivative (D(2)) spectrophotometric one, which allows the determination of RIV in the presence of its degradate at 262 nm (corresponding to zero crossing of the degradate) over a concentration range of 50-500 microg/ml with mean percentage recovery 100.18 +/- 0.