Determination of azidothymidine and its degradation product thymine in pharmaceutical dosage forms by HPLC and HPTLC densitometry

The 3'-azido-3'-deoxythymidine (AZT, Zidovudine) is an antiproliferative and virostatic drug widely used in human immunodeficiency virus type 1 (HIV-1) infection treatment. With respect to side effects of high doses and a short halflife of AZT, a fast and simple detection method for this agent could be helpful. The aim of our study was to determine AZT levels in natural samples (urine, serum, whole blood, and cell cultures, such as the HaCaT line of keratinocytes) without their mineralization and/or purification, by means of electrochemical methods using hanging mercury drop electrode (HMDE). On this electrode, AZT undergoes irreversible reduction at the peak potential near E p À 1.1 V (vs. Ag/AgCl/3 M KCl). Reduction AZT signals were measured by cyclic voltammetry (CV), differential pulse voltammetry (DPV), square-wave voltammetry (SWV), and constant current chronopotentiometric stripping analysis (CPSA). In phosphate buffer (pH 8) the SWV yielded the best AZT signal with the detection limit of 1 nM. The determination of AZT concentration in biological materials is affected by electroactive components, such as proteins and DNA. For monitoring the influence of these compounds, AZT reduction was performed in the presence of 10 mg/ mL calf thymus ssDNA and/or 100 mg/mL bovine serum albumin. In these cases, the detection limit increased to 0.25 mM. Also studied was the AZT concentration in keratinocyte cells (HaCaT line) during cell cultivation. It has been shown that the SWV may be considered as a useful tool for the determination of AZT concentration in cell cultures, and for monitoring AZT pharmacokinetics.

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“…The absorbance maximums of AZT, DNA, and BSA were 267 nm [18], 260 nm and 280 nm [19], respectively.…”

Section: Uv-vis Spectrophotometric Detectionmentioning

confidence: 99%

“…The concentrations of the AZT, DNA and BSA were measured by UV-vis spectrophotometer (Hewlett Packard, Model 8452A, USA) with a diode array in temperature controlled cell (1 cm). The absorbance maximums of AZT, DNA, and BSA were 267 nm [18], 260 nm and 280 nm [19], respectively.…”

Section: Uv-vis Spectrophotometric Detectionmentioning

confidence: 99%

Determination of Azidothymidine – an Antiproliferative and Virostatic Drug by Square‐Wave Voltammetry

et al. 2004

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“…Purine and pyrimidine derivatives and nucleoside analogues form a biologically and pharmaceutically important group of compounds (Youssef et al, 1989;Gaye-Saye and Aaron, 1994). The nucleoside analogue, azidothymidine, 3'-azido-3'deoxythymidine (AZT, BW A-509 U, Zidovudine, Retrovir®) is used in the treatment of acquired immune deficiency syndrome (AIDS) and AIDS-related complex (ARC) (Tomankova and Sabartova, 1990). Fluorinated pyrimidines and their nucleosides are well known to show a significant cytotoxic activity.…”

Section: Introductionmentioning

confidence: 99%

“…Several analytical procedures have been developed for the analysis and physicochemical investigations (Abdullah, 1996;Stevens et al, 1984) of this group of compounds in pharmaceutical, biological, physiological and other samples. These procedures and techniques include: infrared, UV, SRTP (synchronous room-temperature phosphorescence) spectroscopy (Belikov et al, 1989;Amici et al, 1989;Gaye-Seye and Aaron, 1994), gas, thin layer and liquid chromatography (Simek et al, 1994;Simanov, 1994;Guerrieri et al, 1994;Ashihara et al, 1990;Tomankova and Sabartova, 1990). Their luminescence properties have been investigated extensively, because of the fundamental interest in biochemistry and essential role in photochemical and photophysical processes of nucleic acids (Daniels, 1983).…”

Section: Introductionmentioning

confidence: 99%

Thermoanalytical Behaviour of 2-amino- and 2-oxo- Substituted Pyrimidines

Shah¹,

Al-Darabi²,

Rahman³

et al. 2001

J. of Biological Sciences

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Thermoanalytical behaviour of 2-amino-and 2-oxo-substituted pyrimidines studied in an inert atmosphere (N 2) has been described. The simultaneous TG-DTA profiles recorded over the temperature range of ambient-700EC, with a heating rate programmed at 10EC/ min, indicate fairly resolved mass loss stages and peaks. The thermal stability and degradation pattern of the substituted pyrimidines is discussed.

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