Continuous Wavelet Transforms for the Simultaneous Quantitative Analysis and Dissolution Testing of Lamivudine–Zidovudine Tablets

Abstract

Dissolution testing has a very vital importance for a quality control test and prediction of the in vivo behavior of the oral dosage formulation. This requires the use of a powerful analytical method to get reliable, accurate and precise results for the dissolution experiments. In this context, new signal processing approaches, continuous wavelet transforms (CWTs) were improved for the simultaneous quantitative estimation and dissolution testing of lamivudine (LAM) and zidovudine (ZID) in a tablet dosage form. The CWT approaches are based on the application of the continuous wavelet functions to the absorption spectra-data vectors of LAM and ZID in the wavelet domain. After applying many wavelet functions, the families consisting of Mexican hat wavelet with the scaling factor a 256, Symlets wavelet with the scaling factor a 512 and the order of 5 and Daubechies wavelet at the scale factor a 450 and the order of 10 were found to be suitable for the quantitative determination of the mentioned drugs. These wavelet applications were named as mexh-CWT, sym5-CWT and db10-CWT methods. Calibration graphs for LAM and ZID in the working range of 2.0-50.0 µg/mL and 2.0-60.0 µg/mL were obtained measuring the mexh-CWT, sym5-CWT and db10-CWT amplitudes at the wavelength points corresponding to zero crossing points. The validity and applicability of the improved mexh-CWT, sym5-CWT and db10-CWT approaches was carried out by the analysis of the synthetic mixtures containing the analyzed drugs. Simultaneous determination of LAM and ZID in tablets was accomplished by the proposed CWT methods and their dissolution profiles were graphically explored. Key words continuous wavelet transform; determination; dissolution testing; anti-human immunodeficiency virus (HIV) drug; tabletLamivudine (LAM), chemically named (2R,cis)-4-amino-1-(2-hydroxymethyl-1,3-oxathiolan-5-yl)-(1H)-pyrimidin-2-one or (−)-2′,3′-dideoxy, 3′-thiacytidine (3TC) is the (−)-enantiomer of a dideoxy analogue of cytidine. LAM has been used for the treatment of infections with the human immunodeficiency viruses (HIVs) and chronic hepatitis B viruses. LAM is phosphorylated to its active 5′-triphosphate metabolite (LAM triphosphate). The principal mode of action of LAM triphosphate is inhibition of reverse transcriptase via DNA chain termination after incorporation of the nucleoside analogue. LAM triphosphate is a weak inhibitor of mammalian DNA polymerases-α, -β and mitochondrial DNA polymerase-γ LAM is often given in combination whit zidovudine (ZID) in order to provide desirable therapy. ZID or azidothymidine (AZT) has been used for the treatment of HIV/AIDS infectiousness. Its chemical name is 3′-azido-3′-deoxythymidine. ZID is phosphorylated to its active 5′-triphosphate metabolite (ZID triphosphate). ZID triphosphate is inhibition of reverse transcriptase via DNA chain termination after incorporation of the nucleoside analogue. ZID triphosphate is a weak inhibitor of the mammalian DNA polymerase-α and mitochondrial DNA polymerase-γ and has been reported to be incorp...

Bioequivalence and Pharmacokinetics Study of Two Zidovudine/Lamivudine Tablets in Chinese Healthy Volunteers

“…Many methods have been developed to simultaneously and quantitatively detect the concentrations of zidovudine and lamivudine in biological samples and drugs due to the long history of these 2 drugs in research and clinical use. These analytical methods include high-performance liquid chromatography, 10,11 continuous wavelet transforms, 12 high-performance thin-layer chromatography, 13 and liquid chromatography-tandem mass spectrometry. 14 Compared with existing techniques, our method was simpler, more sensitive, and also rapid; sample detection took only 3.3 and 2.5 minutes for zidovudine and lamivudine, respectively.…”

Using Both Classical and Chemometric Chromatographic Measurements to Quantify and Monitor the in‐vitro Dissolution Profiles of Lamivudine and Zidovudine in Combined Tablets

“…Various analytical methods were also reported for the analysis of LAM and ZID such as UV spectroscopic [10][11][12][13][14][15] and chromatographic studies. [10,13,[16][17][18][19][20][21] With cited reference to the literature, it is reasonable to state that HPLC outperformed UV spectroscopy in analyzing these antiretrovirals in the mixtures also containing other pharmaceutical ingredients.…”

Comparative Application of PLS and PCR Methods to Simultaneous Quantitative Estimation and Simultaneous Dissolution Test of Zidovudine - Lamivudine Tablets

“…A review of the literature shows that various conventional analytical methods including spectrophotometry, [1][2][3][4][5] high performance thin layer chromatography, 4 high performance liquid chromatography, [4][5][6][7][8][9][10][11][12][13] high performance liquid chromatography-mass spectrometry 14 and signal processing method 15 were reported for the analysis of ZID and LAM or their combination with other drugs in tablets, human serum and in drug dissolution studies.…”