Adsorption voltammetry of nandrolone phenylpropionate

Abstract

The electrochemical behavior of nandrolone phenylpropionate (NP) at a hanging mercury drop electrode (HMDE) was investigated. The adsorption phenomena were observed by linear sweep voltammetry in NaOH. The electrode reaction was found to be a totally irreversible reduction of the adsorbed Np. In 1 x m o m NaOH, the detection limit and the linear range are 5 x lo-'' and 8 x 10-'"-5 x lO-'rnol/L, respectively. The relative standard deviation of the method is 1.6 % for 1.7 x molL NP. The method was applied to the determination of NP in clinical ampuls.Keywords: Voltammetry, Adsorption, Nandrolone phenylpropionate, Trace analysis Nandrolone phenylpropionate (NP) is a A4-3-ketosteroid drug common used as anabolic agent for improving the nitrogen retention in humans suffering from protein-consuming diseases. The improved nitrogen retention results in additional build-up of muscles under the conditions of modem power-training. To prevent these harmful effect on athletes, and for ethical reasons, the International Olympic Committee (IOC) has blacklisted all anabolic drugs [l]. This drug has also been listed in the detection roll by the IOC [2]. High performance liquid chromatography [3] and spectrophotometry [4, 51 have been applied to determine NP.Adsorption voltammetry is a new electroanalytical technique which is well suited to the determination of trace amounts of organic compounds and inorganic complexes 16, 71. Numerous articles concerning this method have been published [7]. Owing to the higher accumulation effect, adsorption voltammetry has significantly higher sensitivity compared with polarography, voltammetry and other methods. Up to now, the adsorption-voltammetric determination of NP has not been reported.In this study the adsorption voltammetry of NP at a hanging mercury electrode (HMDE) was developed. A linear relationship holds between the peak height and the concentration of NP in the concentration range 8 x 10-"-5 x m o m with good precision.The limit of detection is 5 x 10-lOmol/L for an accumulation time of 600 s. The method has been applied to the determination of NP in clinical ampuls. Adsorptive and voltammetric characteristics of NP:In 1 x I 0-7 m o m NaOH solution, no reduction peak appears on the adsorption voltammogram over the potential range from -1 .O to -1.8 V. When a micromolar level of NP is added to this solution, a very sensitive reduction peak appears at about -1.66V (Fig. 1). It seems clear that this sensitive peak results from reduction of NP. It was found that NP can be reduced at the mercury electrode in NaOH, KCI, HOAc + NaOAc, NH3 + N h C l and NH3 solutions.The highest peak current occurs in the NaOH solution. The concentration of NaOH affects noticeably the peak current of reduction of the adsorbed NP. The peak current reaches a maximum value when the concentration of NaOH is 1 ~l O -~m o l / L . So

Electrochemical Sensor for Anti-Doping in Athletes

“…9 ND boosts muscle strength and endurance by increasing testosterone and endogenous testosterone levels, and it was most probably used as a doping medication in sports in the 1960s. Many analysis techniques for identifying and analyzing ND amounts in biofluids and clinical specimens have been explored as a result, including liquid chromatography, 10 mass spectrometry, 11 gas chromatography, 12 capillary electrophoresis, 13 spectrophotometry, 14 electrochemical methods, 15,16,17,18 Raman spectroscopy, 19 near-Infrared Spectroscopy 20 and enzyme-linked immunosorbent assay kit (ELISA). 21 When it came to detecting anabolic steroids for clinical samples, electrochemical methods surpassed the others in respect of selectivity and sensitivity.…”