Electrochemically Pretreated Sensor Based on Screen-Printed Carbon Modified with Pb Nanoparticles for Determination of Testosterone

Abstract

Testosterone (TST), despite its good properties, may be harmful to the human organism and the environment. Therefore, monitoring biological fluids and environmental samples is important. An electrochemically pretreated screen-printed carbon sensor modified with Pb nanoparticles (pSPCE/PbNPs) was successfully prepared and used for the determination of TST. The surface morphology and electrochemical properties of unmodified and modified sensors were characterized by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), scanning and transmission electron microscopy (SEM and TEM), and energy-dispersive X-ray spectroscopy (EDS). Selective determinations of TST at the pSPCE/PbNPs were carried out by differential pulse adsorptive stripping voltammetry (DPAdSV, EPb dep.and TST acc. of −1.1 V, t Pb dep.and TST acc. of 120 s, ΔEA of 50 mV, ν of 175 mV s−1, and tm of 5 ms) in a solution containing 0.075 mol L−1 acetate buffer of pH = 4.6 ± 0.1, and 7.5 × 10−5 mol L−1 Pb(NO3)2. The analytical signal obtained at the potential around −1.42 V (vs. silver pseudo-reference electrode) is related to the reduction process of TST adsorbed onto the electrode surface. The use of pSPCE/PbNPs allows obtaining a very low limit of TST detection (2.2 × 10−12 mol L−1) and wide linear ranges of the calibration graph (1.0 × 10−11–1.0 × 10−10, 1.0 × 10−10–2.0 × 10−9, and 2.0 × 10−9–2.0 × 10−8 mol L−1). The pSPCE/PbNPs were successfully applied for the determination of TST in reference material of human urine and wastewater purified in a sewage treatment plant without preliminary preparation.

Electrochemical testosterone biosensor based on pencil graphite electrode electrodeposited with copper oxide nanoparticles

“…A comparison between the proposed sensor platform and previously reported sensors is provided in table 2. When compared to voltammetric methods utilizing on adsorptive stripping strategy [2,4,6,7,31], it becomes evident that the CuONP/PGE exhibits high sensitivity towards TST detection without the requirement of any surfactants like CTAB (cetyltrimethylammonium bromide) for enhancing analytical signal.…”

“…The major physiological conditions associated with either high or low levels of TST in the blood include type-2 diabetes, coronary artery disease, osteoporosis, kidney stone, and prostate cancer. Moreover, TST is also utilized as a medication to treating some diseases, such as breast cancer and menorrhagia in females and hypogonadism in males [4,5].…”

“…The TST level has been traditionally monitored by techniques such as mass spectrometry, tandem mass spectrometry, high-performance liquid chromatography, gas-liquid chromatography/mass spectrometry and enzyme-linked immunosorbent assay [1,4,10]. However, these methods require sophisticated and expensive instrumentation, highly trained laboratory staff, time-consuming and complicated sample pretreatment procedures, leading to significant delays between sample collection and obtaining results.…”

“…Recent studies in the literature have focused on enhancing the sensitivity of the electrochemical sensor through electrode modifications [14]. For instance, various approaches have been explored, including the decoration of the working electrode surface with conducting mediators [15,16] such as magnetic nanoparticles [10], metallic nanoparticles [4,17], metal oxide nanoparticles [3], conducting film [1,7,18,19], or carbon nanotubes [5] to more sensitive detection of TST.…”

The Influence of Graphene Oxide Composition on Properties of Surface-Modified Metal Electrodes

“…The recorded response results from direct transformation of the desired chemical information (concentration, activity) into a current signal (potential, current, resistance, or capacity), according to the selected method. Voltammetry is considered as one of the most sensitive electroanalytical methods, suitable for the determination of trace amounts of many metals and compounds in clinical, industrial, and environmental samples [ 1 , 2 , 3 , 4 ]. Various voltammetric techniques provide a wealth of chemical, electrochemical, and physical information, such as quantitative analysis, diffusion and reaction rate constants, and number of electrons involved in redox reactions [ 5 , 6 ].…”