Hacer Azak

Synthesis of an amine-functionalized naphthalene-containing conducting polymer as a matrix for biomolecule immobilization

N-functionalized dithienopyrroles (DTP-NH2) were synthesized and electropolymerized onto a graphite electrode as a novel conducting polymer matrix for biomolecule immobilization. 1H-NMR and 13C-NMR were utilized to investigate the characteristics of the monomer. After that, glucose oxidase (GOx) was immobilized onto the amino-functionalised matrix by means of glutaraldehyde. The surface morphologies of both DTP-NH2 and DTP-NH2–GOx were visualised by using SEM and fluorescence microscopy. The chronoamperometric signals of the electrochemical DTP-NH2–GOx biosensors were measured by monitoring the O2 consumption during an enzymatic reaction in the presence of glucose at −0.7 V. After the optimization of the pH and scan number of the polymer deposition in batch mode, the DTP-NH2–GOx biosensor was also tested in Flow Injection Analysis (FIA) mode. The DTP-NH2–GOx biosensors had a very good linearity between 0.05 and 1.0 mM, and between 0.1 and 2.5 mM for glucose in batch and FIA modes, respectively. Finally, it was applied for glucose analysis in real samples where commercial glucose kits were used as the reference method to verify the data obtained with the proposed biosensor.

Synthesis of 1,4-bis(indolin-1-ylmethyl)benzene derivatives and their structure-activity relationships for the interaction of human carbonic anhydrase isoforms I and II.

Several 1,4-bis(indolin-1-ylmethyl)benzene-based compounds containing substituents such as five, six and seven cyclic derivatives on indeno part (9a-c) were prepared and tested against two members of the pH regulatory enzyme family, carbonic anhydrase (CA). The inhibitory potencies of the compounds at the human isoforms hCA I and hCA II targets were analyzed and KI values were calculated. KI values of compounds for hCA I and hCA II human isozymes were measured in the range of 39.3-42.6μM and 0.17-0.29μM, respectively. The structurally related compound indole was also tested in order to understand the structure-activity relationship. Most of the compounds showed good CA inhibitory efficacy. In silico docking studies of these derivatives within hCA I and II were also carried out and results are supported the kinetic assays.

A novel immobilization matrix for the biosensing of phenol: self assembled monolayers of calixarenes

Abstract Aim: The development of calixarene based phenol biosensor. Methods: This study describes the application of a calixarene derivative, 5,17-diamino-25,27-bis(3-thiol-1-oxypropane)-26,28-dihydroxycalix[4]arene (HS-Calix-NH2) which has both amino and thiol functionalities, in the practical surface modifications for biomolecule binding. The structure of HS-Calix-NH2 allows easy interaction with Au surface and one-step biomolecule immobilization. Self-assembled monolayers (SAMs) of p-amino-functionalized mercaptoalkylcalixarene (HS-Calix-NH2) were formed onto the Au electrode. Then, Laccase (Lac) enzyme was immobilized onto the modified surface by crosslinking with glutaraldehyde (GA). Resulted electrode (HS-Calix-NH2/Lac) was used for the electrochemical analysis of phenolic compounds at −50 mV. Results: The linearity was observed in the range of 0.1–100 μM and 1.0–100 μM for catechol and phenol, respectively. The potential use of the biosensor was investigated for phenol analysis in artificial samples which simulate the industrial waste water, which is highly acidic and composed of concentrated salt, without needing any sample pre-treatment step. Conclusion: The prepared Lac biosensor has a potential for rapid, selective and easy detection of phenolic contaminations in samples.