The Use of a Polyphenoloxidase Biosensor Obtained from the Fruit of Jurubeba (Solanum paniculatum L.) in the Determination of Paracetamol and Other Phenolic Drugs

Abstract

The vegetable kingdom is a wide source of a diverse variety of enzymes with broad biotechnological applications. Among the main classes of plant enzymes, the polyphenol oxidases, which convert phenolic compounds to the related quinones, have been successfully used for biosensor development. The oxidation products from such enzymes can be electrochemically reduced, and the sensing is easily achieved by amperometric transducers. In this work, the polyphenoloxidases were extracted from jurubeba (Solanum paniculatum L.) fruits, and the extract was used to construct a carbon paste-based biosensor for pharmaceutical analysis and applications. The assay optimization was performed using a 0.1 mM catechol probe, taking into account the amount of enzymatic extract (50 or 200 μL) and the optimum pH (3.0 to 9.0) as well as some electrochemical differential pulse voltammetric (DPV) parameters (e.g., pulse amplitude, pulse range, pulse width, scan rate). Under optimized conditions, the biosensor was evaluated for the quantitative determination of acetaminophen, acetylsalicylic acid, methyldopa, and ascorbic acid. The best performance was obtained for acetaminophen, which responded linearly in the range between 5 and 245 μM (R = 0.9994), presenting a limit of detection of 3 μM and suitable repeatability ranging between 1.52% and 1.74% relative standard deviation (RSD).

Development of a Polyphenol Oxidase Biosensor from Jenipapo Fruit Extract (Genipa americana L.) and Determination of Phenolic Compounds in Textile Industrial Effluents

“…The best response was obtained with 100 μL JeEE, which corresponds to an enzymatic activity of 593 U/mg proteins. It was clear that higher concentrations of crude vegetal extract lead to saturation, therefore hindering further detection and decreasing sensitivity ( Figure 2 B), and this event was previously reported in the literature [ 26 ]. The best pH was of 7.0 ( Figure 2 C).…”

“…The biological function of PPOs is strictly related to their capacity to reversibly bond to oxygen through a copper (Cu 2+ ) active site, thus either oxidizing catechol to quinone or reducing quinone to catechol. These events are potential dependent and involve electron transfer, which is thereby detected in methods such as DPV [ 25 , 26 ].…”

“…The oxidation of catechol can be assessed through an anodic scan, whereas the reduction of quinone to catechol is detected through a cathodic scan [ 25 , 26 ]. The aforementioned redox processes are represented below ( Scheme 1 ).…”

Nanostructured TiO2 Carbon Paste Based Sensor for Determination of Methyldopa

“…Indeed, the low consumption of reagents, cheapness of electrochemical apparatus, combined with good sensibility, broad applicability, and suitable selectivity are some of the main attractive features of this method. Moreover, both sensibility and selectivity can be improved by changes in electrode matrix composition [12,13,14,15,16,17,18,19,20,21].…”

“…Literature reports the use of several sensing materials in the determination of anti-hypertensive drugs such as methyldopa. Amongst these electrodic devices, the most used are boron doped diamond [22,23] and glassy carbon electrode (GCE) [21,22,23,24]. Albeit widely explored in analytical studies, diamond-based electrodes are unpractical due to their high cost, while GCE may not provide adequate reproducibility hence electrode surface fouling.…”