Autor: |
Amin AS; Department of Chemistry, Faculty of Science, Benha University, Benha, Egypt. asamin2002@hotmail.com, Ahmed IS, Dessouki HA, Gouda EA |
Jazyk: |
angličtina |
Zdroj: |
Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy [Spectrochim Acta A Mol Biomol Spectrosc] 2003 Mar 01; Vol. 59 (4), pp. 695-703. |
DOI: |
10.1016/s1386-1425(02)00226-3 |
Abstrakt: |
Three simple, accurate and sensitive colorimetric methods (A, B and C) for the determination of ranitidine HCl (RHCl) in bulk sample, in dosage forms and in the presence of its oxidative degradates are described. The first method A is based on the oxidation of the drug by N-bromosuccinimide (NBS) and determination of the unreacted NBS by measurement of the decrease in absorbance of amaranth dye (AM) at a suitable lambda(max)=520 nm. The methods B and C involve the addition of excess Ce(4+) and determination of the unreacted oxidant by decrease the red color of chromotrope 2R (C2R) at a suitable lambda(max)=528 nm for method B or decrease the orange pink color of rhodamine 6G (Rh6G) at a suitable lambda(max)=526 nm for method C. Regression analysis of Beer-Lambert plots showed good correlation in the concentration ranges 0.2-3.6, 0.1-2.8 and 0.1-2.6 microg ml(-1) for methods A, B and C, respectively. The apparent molar absorptivity. Sandell sensitivity, detection and quantitation limits were calculated. For more accurate results, Ringbom optimum concentration ranges were 0.3-3.4, 0.2-2.6 and 0.2-2.4 microg ml(-1) for methods A, B and C, respectively. Analyzing pure and dosage forms containing RHCl tested the validity of the proposed methods. The relative standard deviations were =1.38 with recoveries 98.9-101.0%. |
Databáze: |
MEDLINE |
Externí odkaz: |
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