The development of a novel urea sensor using polypyrrole

Abstract

a b s t r a c tThe urease enzyme (Urs) was successfully incorporated into a polypyrrole film (PPy) in one simple electropolymerisation step. The films were formed using different dopant anions. The polypyrrole-urease-chloride film (PPy-Urs-Cl) was deposited from a simple chloride dopant, and the polypyrrole-urease-sulfonated-␤-cyclodextrin (PPy-Urs-SCD) was formed using a sulfonated-␤-cyclodextrin (SCD) dopant. The presence of the Urs within the polymer film was evident from the fibrous morphology, observed in the SEM micrographs, and the presence of nickel, arising from the active site of the urease enzyme. The sensing ability of the films and their enzyme-free counterparts (i.e., PPy-Cl and PPy-SCD) towards urea was investigated. The dopant anion plays an important role in the sensitivity of the polymer films towards urea. The PPy-Urs-SCD film has a superior sensitivity of 5.79 C M −1 compared to 0.76 C M −1 for the PPy-Urs-Cl polymer film. Furthermore, the negative groups on the SCD eliminate interference from common interfering compounds, such as ascorbic acid.

The incorporation and controlled release of dopamine from a sulfonated β–cyclodextrin–doped conducting polymer

“…Polypyrrole has been doped with anionic CDs to give conducting polymer matrices that exhibit cation exchange properties as the large cyclodextrin is immobile and is not lost on reduction of the polymer [21,22]. These CD-doped polypyrrole films have been used in the electrochemical detection of dopamine [23] and urea [24,25].…”

A high-performance nonenzymatic piezoelectric sensor based on molecularly imprinted transparent TiO2 film for detection of urea

“…Therefore, it is very important to monitor the level of urea to determine the health of the livers and kidneys in the human body. In the past years, some analytical methods have been developed for urea detection, such as enzymatic assay (Hamilton and Breslin, 2014;Yang and Zhang, 2013;Siqueira et al, 2014;Lin et al, 2013), gas chromatography (Kessler and Siekmann, 1999), calorimetry (Francis et al, 2002), high-performance liquid chromatography , fluorimetry (Roch-Ramel, 1967), surface plasmon resonance (Verma and Gupta, 2014) and electrochemistry (Mondal and Sangaranarayanan, 2013;Srivastava et al, 2012). Despite many advances in urea detection, many of these methods still do not meet the growing demand for more sensitive and selective detection of urea.…”

Self-Assembly of Gold Nanoparticles on Gold Core-Induced Polypyrrole Nanohybrids for Electrochemical Sensor of Dopamine

“…[7][8][9] Polypyrrole (PPy), as one of the most promising CPs because of its ease of synthesis, good redox properties, high conductivity and excellent environmental stability, 10 has wider potential applications in sensors and electric devices. [11][12][13][14][15] Metallic nanoparticles (MNPs), such as gold nanoparticles (AuNPs), due to their unique structure and fascinating properties such as high e®ective surface area, strong adsorption ability, good biocompatibility and conductivity, have been extensively used to fabricate di®erent kinds of sensors. [16][17][18][19][20][21] It was found that the conductivity and sensing behavior of CPs could be further improved by embedding MNPs into polymer matrix to form a CP-MNP composite.…”