Photoelectroanalytical Detection of Adrenaline Based on DNA and TiO2 Nanoparticles Sensitized with Bis(ethylenedithio)tetrathiafulvalene Exploiting LED Light

Abstract

In this study, a photoelectroanalytical sensor for determination of adrenaline based on deoxyribonucleic acid (DNA) and anatase titanium dioxide (TiO 2 ) nanoparticles sensitized with bis(ethylenedithio)tetrathiafulvalene (BEDT-TTF) was developed, which we henceforward call BEDT-TTF/DNA/TiO 2 /ITO. The photoelectroanalytical sensor showed high photocurrent to adrenaline under visible light emitting diode (LED) light irradiation in comparison to each component of the composite material. Under optimized conditions, the BEDT-TTF/DNA/TiO 2 /ITO sensor shows a linear response range from 10 nmol L -1 up to 100 µmol L -1 with a sensitivity of 8.1 nA L µmol -1 and limit of detection of 1 nmol L -1 for the detection of adrenaline. The photoelectrochemical sensor showed high photocurrent to adrenaline in comparison to photocurrent response to ascorbic acid and uric acid. The BEDT-TTF/DNA/TiO 2 /ITO photoelectrochemical sensor was successfully applied to urine samples, with recovery values between 96 and 106%. Keywords: adrenaline, photoelectrochemical sensor, visible LED light, deoxyribonucleic acid IntroductionAdrenaline, also known as epinephrine, is one of the most important message transfer compound in the mammalian central nervous system, which exist as an organic cation in the nervous tissue and the biological body fluid. 1 The level of adrenaline in the body affects a series of actions of the nervous system including the regulation of blood pressure, heart rate, lipolysis, immune response and glycogen metabolism. 2 In addition, adrenaline has been advocated during early cardiopulmonary resuscitation, early defibrillation and early advanced care in cardiac arrest for decades. 3 Therefore, the quantification of adrenaline in biological samples is of high interest nowadays. Urine represents one of the most easily attainable and, consequently, very common samples in adrenaline clinical analysis and diagnostics. The levels of adrenaline in biological fluids such as urine depends on the age and condition of the patient. 4 For healthy people, for example, the physiological concentration of adrenaline found in urine samples are in nanomolar level (22-109 nmol L -1 ). 5A number of analytical methodologies have been proposed for determination of adrenaline such as fluorimetric, 6 spectrophotometric, 7 enzymatic radioimmunoassay, 8 gas chromatography, 9 high performance liquid chromatography, 10 capillary electrophoresis 11 and electrochemical methods. [12][13][14][15] Despite the high number of analytical methods for adrenaline determination, most of them suffer from some disadvantages such as high cost, long analysis time, extensive sample pretreatment based on derivatization, extraction and purification as well as demands for highly trained users. The fluorometric and radioenzymatic assays are presently the most widely used techniques for the estimation of plasma, urine and tissue adrenaline. The fluorometric assay lacks specificity and sensitivity. The radioenzymatic assay is significantly more sensitive and specific...

Determination of Solubility of 4-(2-Hydroxyethyl)-1-piperazineethanesulfonic Acid and its Sodium Salt in Acetonitrile and Voltammetric Investigation of Sulphonamide Drugs in Different Solvents in Their Absence and Presence

“…This buffer was used in a vast number of studies. In many intra-and extracellular electrochemical studies it served as an appropriate choice [1][2][3][4] and in protein based detection applications [5,6].…”