Combined application of continuous wavelet transform-zero crossing technique in the simultaneous spectrophotometric determination of perindopril and indapamid in tablets

Quimica nova

Pektaş¹  , Gözde¹  Dinç, Erdal² 

[1] Ankara University, Ankara, Turkey;Çankaya University, Ankara, Turkey

关键词: continuous wavelet transform;    zero crossing technique;    perindopril.;   

DOI  :  10.1590/S0100-40422009000600010

学科分类：化学（综合）

来源: Sociedade Brasileira de Quimica

【 摘 要 】

Signal processingmethods based on the combined use of the continuous wavelet transform(CWT) and zero-crossing technique were applied to the simultaneous spectrophotometricdetermination of perindopril (PER) and indapamide (IND) in tablets. These signalprocessing methods do not require any priory separation step. Initially, variouswavelet families were tested to identify the optimum signal processing givingthe best recovery results. From this procedure, the Haar and Biorthogonal1.5continuous wavelet transform (HAAR-CWT and BIOR1.5-CWT, respectively) were foundsuitable for the analysis of the related compounds. After transformation ofthe absorbance vectors by using HAAR-CWT and BIOR1.5-CWT, the CWT-coefficientswere drawn as a graph versus wavelength and then the HAAR-CWT and BIOR1.5-CWTspectra were obtained. Calibration graphs for PER and IND were obtained by measuringthe CWT amplitudes at 231.1 and 291.0 nm in the HAAR-CWT spectra and at 228.5and 246.8 nm in BIOR1.5-CWT spectra, respectively. In order to compare the performanceof HAAR-CWT and BIOR1.5-CWT approaches, derivative spectrophotometric (DS) methodand HPLC as comparison methods, were applied to the PER-IND samples. In thisDS method, first derivative absorbance values at 221.6 for PER and 282.7 nmfor IND were used to obtain the calibration graphs. The validation of the CWTand DS signal processing methods was carried out by using the recovery studyand standard addition technique. In the following step, these methods were successfullyapplied to the commercial tablets containing PER and IND compounds and goodaccuracy and precision were reported for the experimental results obtained byall proposed signal processing methods.

【 授权许可】

CC BY