ElectroSens Platform with a Polyelectrolyte-Based Carbon Fiber Sensor for Point-of-Care Analysis of Zn in Blood and Urine

Abstract

In this paper, we describe an electrochemical sensing platform—ElectroSens—for the detection of Zn based on self-assembled polyelectrolyte multilayers on the carbon fiber (CF) electrode surface. The CF-extended surface facilitates the usage of a small volume electrochemical cell (1 mL) without stirring. This approach allows making a low-cost three-electrode platform. Working electrode modification with layer-by-layer assembly of polyethyleneimine (PEI), poly(sodium 4-styrenesulfonate) (PSS), and mercury nitrate layers eliminates solution toxicity and provides stable stripping voltammetry measurements. The stable, robust, sustainable, and even reusable Ag/AgCl reference electrode consists of adsorbed 32 PEI-KCl/PSS-KCl bilayers on the CF/silver paste separated from the outer solution by a polyvinyl chloride membrane. The polyelectrolyte-based sensor interface prevents adsorption of protein molecules from biological liquids on the CF surface that leads to a sensitivity increase of up to 2.2 μA/M for Zn 2+ detection and provides a low limit of detection of 4.6 × 10 –8 M. The linear range for Zn detection is 1 × 10 –7 to 1 × 10 –5 M. A portable potentiostat connected via wireless to a smartphone with an android-based software is also provided. The ElectroSens demonstrates reproducibility and repeatability of data for the detection of Zn in blood and urine without the digestion step.

Determination of sodium and potassium ions in patients with SARS-Cov-2 disease by ion-selective electrodes based on polyelectrolyte complexes as a pseudo-liquid contact phase

“…Previous studies have shown the possibility of immobilizing polyelectrolyte nanolayers on the surface of a carbon ber. 31 This study demonstrates a new interface: hydrophobic carbon berhydrophilic layers of polyelectrolyteshydrophobic ionselective membrane. This interface enables to propose the potential method of correlation for COVID-19 with electrochemical measurements using ion-selective electrodes to determine the sodium and potassium ion concentration change in urine and blood serum (Fig.…”

“…32 Previously, we have developed a portative platform based on a carbon ber electrode for Zn detection in blood and urine samples. 31 We afforded the carbon ber electrode as a substrate for the ion-selective electrode with pseudo-liquid junction. Previous studies have shown the possibility of immobilizing polyelectrolyte nanolayers on the surface of a carbon ber.…”

Nanoparticles in Polyelectrolyte Multilayer Layer-by-Layer (LbL) Films and Capsules—Key Enabling Components of Hybrid Coatings

“…Photocatalytic reduction [107] of noble metal particles on titania core [95] leads to dual-wavelength responsiveness: in the UV to near-IR regions of electromagnetic spectrum. It is possible to regulate photocatalytically (auto-catalytic) waves of enzymatic reactions [108], switch biofilm fluorescence [109], build a platform for a chemical logic device [110], and perform sustainable diagnostics [111][112][113]. The trend in the field of encapsulated systems is to combine different functions in one capsule matrix.…”

Determination of Uric Acid in Artificial Saliva with Compact AMP3291 Reader and Au Nanoparticles Modified Electrode

“…[10,11]. Considering that custom sensing platforms allow setting the specific parameters for a defined analyte (e.g., time, current, applied potential), a variety of electronic systems with ECS have been developed for decentralized measurements of glucose [12], H 2 O 2 [13], dopamine [14], progesterone [15], cortisol [16], zinc [17] and diagnosis of celiac disease [18].…”

“…In the second design stage, the electronic input is linked to microcontroller (MCU) platforms like Arduino, ESP32 [14] or Raspberry Pi [19] to perform digitalization of the acquired signals, synchronize functions and configure internal operational parameters. The MCU also controls the mechanisms to store and present the acquired data by using USB communication protocols to a computer [24], wireless connection [14,18] or even cloud database [17]. Following this general approach, custom equipment has been developed in a simple and compact format to perform electrochemical techniques such as cyclic voltammetry (CV) [16,25], differential pulse voltammetry (DPV) [13,24] and amperometry (AMP) [7,12].…”