La(OH)3 Multi-Walled Carbon Nanotube/Carbon Paste-Based Sensing Approach for the Detection of Uric Acid—A Product of Environmentally Stressed Cells

Abstract

This paper aims to develop an amperometric, non-enzymatic sensor for detecting and quantifying UA as an alert signal induced by allergens with protease activity in human cell lines (HEK293 and HeLa). Uric acid (UA) has been classified as a damage-associated molecular pattern (DAMP) molecule that serves a physiological purpose inside the cell, while outside the cell it can be an indicator of cell damage. Cell damage or stress can be caused by different health problems or by environmental irritants, such as allergens. We can act and prevent the events that generate stress by determining the extent to which cells are under stress. Amperometric calibration measurements were performed with a carbon paste electrode modified with La(OH)3@MWCNT, at the potential of 0.3 V. The calibration curve was constructed in a linear operating range from 0.67 μM to 121 μM UA. The proposed sensor displayed good reproducibility with an RSD of 3.65% calculated for five subsequent measurements, and a low detection limit of 64.28 nM, determined using the 3 S/m method. Interference studies and the real sample analysis of allergen-treated cell lines proved that the proposed sensing platform possesses excellent sensitivity, reproducibility, and stability. Therefore, it can potentially be used to evaluate stress factors in medical research and clinical practice.

Electrochemical Determination of Morphine in Urine Samples by Tailoring FeWO4/CPE Sensor

“…The electrochemical method gives us a possibility of real-time and on-site analysis, where equipment is not expensive and is easy to handle [ 8 , 9 , 10 ]. In addition, with the development of nanomaterials, we obtain the ability to synthesize a large number of high-performance electrochemical sensors in order to create the most sensitive and selective sensors for a specific analyte [ 8 , 11 , 12 , 13 , 14 , 15 ].…”

“…The electrochemical method gives us a possibility of real-time and on-site analysis, where equipment is not expensive and is easy to handle [ 8 , 9 , 10 ]. In addition, with the development of nanomaterials, we obtain the ability to synthesize a large number of high-performance electrochemical sensors in order to create the most sensitive and selective sensors for a specific analyte [ 8 , 11 , 12 , 13 , 14 , 15 ]. Over the years, many electrochemical sensors based on glassy carbon electrodes [ 8 , 10 , 13 , 14 , 16 ], platinum electrodes, and carbon-based electrodes have been developed [ 9 , 10 , 11 , 12 , 17 , 18 , 19 ].…”

“…In addition, with the development of nanomaterials, we obtain the ability to synthesize a large number of high-performance electrochemical sensors in order to create the most sensitive and selective sensors for a specific analyte [ 8 , 11 , 12 , 13 , 14 , 15 ]. Over the years, many electrochemical sensors based on glassy carbon electrodes [ 8 , 10 , 13 , 14 , 16 ], platinum electrodes, and carbon-based electrodes have been developed [ 9 , 10 , 11 , 12 , 17 , 18 , 19 ]. As modifiers for the electrochemical detection of MORPH, some of the following modifiers were used: cobalt–hexacyanoferrate particles, indium tin oxide modified with Prussian dye, carbon nanotubes and chitosan, palladium aluminum, multiwall nanotubes, and graphene dope [ 5 , 6 , 7 , 20 , 21 ].…”

Microspherical Titanium-Phosphorus Double Oxide: Hierarchical Structure Development for Sensing Applications

“…For the electrode characterization, a 5 mM mixture of K 3 [Fe(CN) 6 ] /K 4 [Fe(CN) 6 ] (1:1) in 0.1 M KCl was used as a testing solution, and electrochemical impedance spectroscopy (EIS) in the range of 10 mHz to 10 kHz and cyclic voltammetry (CV) in the potential range of −0.5 V to 1.2 V at a scan rate of 50 mV/s, were employed. For the development of analytical procedures, square wave voltammetry was used [ 31 ].…”

“…Percentages were calculated as part of graphite powder only, while the percentage of oil was always constant at 20%. After homogenization of the mixture, the home made Teflon body was filled with carbon paste, and the surface of the electrode was cleaned with paper and used without additional purification [ 31 , 32 ].…”