ISSN print edition: 0366-6352
ISSN electronic edition: 1336-9075
Registr. No.: MK SR 9/7
Sensitive determination of nitrogenous hydrochloride drugs via their reaction with ammonium molybdate
Suling Feng and Limin Guo
College of Chemistry and Environmental Science, Henan Normal University, Xinxiang, 453007, China
Received: 3 October 2007 Revised: 14 December 2007 Accepted: 21 December 2007
Abstract: In a hydrochloric acid medium, benzhexol hydrochloride, cyproheptadine hydrochloride, and maprotiline hydrochloride, can react
with ammonium molybdate to form ion-association complexes by virtue of electrostatic attraction and hydrophobic interaction
which result in a significant enhancement of the resonance light scattering intensity. The maximum scattering wavelengths
were found at 364 nm, 364 nm, and 381 nm for benzhexol hydrochloride, cyproheptadine hydrochloride, and maprotiline hydrochloride
systems, respectively. Spectral characteristics of the three systems, influencing factors, and optimum conditions were investigated.
The reason of resonance light-scattering enhancement and the mechanism of interactions between the drugs and ammonium molybdate
were also discussed. Based on the linear relationship between the enhanced intensity of resonance light scattering and the
concentration of drugs, a highly sensitive method for the determination of the three drugs was developed, the detection limits
being 0.0110 μmol L−1, 0.0038 μmol L−1, and 0.0155 μmol L−1 for benzhexol hydrochloride, cyproheptadine hydrochloride, and maprotiline hydrochloride, respectively. The method was successfully
applied to the determination of the investigated drugs in pharmaceutical, serum, and urine samples.
Keywords: resonance light scattering - ammonium molybdate - benzhexol hydrochloride - cyproheptadine hydrochloride - maprotiline hydrochloride - absorption spectra
Full paper is available at www.springerlink.com.
Chemical Papers 62 (4) 350–357 (2008)