A Molecularly Imprinted Electrochemical Gas Sensor to Sense Butylated Hydroxytoluene in Air

Abstract

Alzheimer’s disease (AD) is a neurodegenerative disease, which affects millions of people worldwide. Curing this disease has not gained much success so far. Exhaled breath gas analysis offers an inexpensive, noninvasive, and immediate method for detecting a large number of diseases, including AD. In this paper, a new method is proposed to detect butylated hydroxytoluene (BHT) in the air, which is one of the chemicals found in the breath print of AD patients. A three-layer sensor was formed through deposition of a thin layer of graphene onto a glassy carbon substrate. Selective binding of the analyte was facilitated by electrochemically initiated polymerization of a solution containing the desired target molecule. Subsequent polymerization and removal of the analyte yielded a layer of polypyrrole, a conductive polymer, on top of the sensor containing molecularly imprinted cavities selective for the target molecule. Two sets of sensors have been developed. First, the graphene sensor has been fabricated with a layer of reduced graphene oxide (RGO) and tested over 5–100 part per million (ppm). For the second batch, Prussian blue was added to graphene before polymerization, mainly for enhancing the electrochemical properties. The sensor was tested over 0.02-1 parts per billion (ppb) level of concentration while the sensor resistance has been monitored.

Paper-Based Platform with an In Situ Molecularly Imprinted Polymer for β-Amyloid

“…Milli-Q laboratory grade ultrapure water (conductivity <0.1 μS/cm) was used to prepare all solutions, and all buffer solutions were prepared in PBS (1.0 × 10 –2 mol/L, pH 7.36). Potassium hexacyanoferrate III (K 3 [Fe­(CN) 6 ]) and potassium hexacyanoferrate II (K 4 [Fe­(CN) 6 ]) trihydrate were purchased from Riedel-de Häen; PBS was purchased from Amresco; potassium chloride (KCl) and oxalic acid dihydrate were purchased from Merck; ethanol absolute (99.5%) was purchased from PanReac; EDOT 97% was purchased from Alfa Aesar; FBS and ATP 96% were purchased from Acros Organics; β-amyloid − human (≥95%) was purchased from GenScript; and trypsin solution 10×, O PDA, BSA, Crea, and Glu were purchased from Sigma-Aldrich.…”

“…Their monomer of choice was aniline, for being stable and easily electropolymerized, much alike phenylenediamine. Emam et al 37 opted for pyrrole, whose electropolymerization conditions are well studied because their MIP-based sensor was very innovative by diagnosing AD in a noninvasive method through the breath of the patient. It is important to highlight that the previously described MIP biosensors, devoted to Aβ-42, may be developed to target other biomarkers circulating in the blood, including Aβ-42 derivatives, most recently established as highly significant in terms of AD.…”

“…Their monomer of choice was aniline, for being stable and easily electropolymerized, much alike phenylenediamine. Emam et al . opted for pyrrole, whose electropolymerization conditions are well studied because their MIP-based sensor was very innovative by diagnosing AD in a noninvasive method through the breath of the patient.…”

Preparation and applications of electrochemical chemosensors based on carbon-nanomaterial-modified molecularly imprinted polymers

“…With regard to the electrochemical sensing of nonelectroactive targets, redox probes are often used for signal outputs. Redox probes include the frequently used [Fe(CN) 6 ] 3−/2− , 136,138,158,159 Prussian blue (PB), 120,121,135,179 N 2 H 4 ·H 2 O, 173 etc. Wang et al reported a 3D MIP electrochemical sensor based on PB-mediated amplification together with signal enhancement of ordered CKM-3 for the quantification of MTMC.…”

Síntese e caracterização de filmes nanocompósitos de óxido de grafeno reduzido, nanotubos de carbono e azul da Prússia para a determinação de peróxido de hidrogênio e cloro ativo

“…Em 1994 Karyakin e colaboradores demonstraram um eletrodo modificado com AP como uma ferramenta poderosa para a detecção de peróxido de hidrogênio em baixos valores de potencial. 44 Desde então, o AP e seus análogos vem sendo estudados como possíveis sensores para uma série de moléculas além do peróxido, como sulfito, 50 K + e Na + , 28 pesticidas, 51 colesterol, 52 BHT, 53 glicose, 54 rutina, 55…”