A Simple Quartz Crystal Microbalance Nucleic Acid Sensor for Detection of Telomerase

Abstract

A simple, fast, inexpensive sensitive/selective nucleic acid sensor based on the quartz crystal microbalance system (QCM) was developed for the detection of telomerase. A specially designed oligonucleotide probe, that is complementary to the template region of the telomerase enzyme, was immobilized onto the silver electrodes of piezoelectric crystals with polyethyleneimine adhesion cross-linked with glutaraldehyde. Optimum coating and immobilization conditions were determined. The QCM nucleic acid sensor was used for the detection of telomerase enzyme in human cervix carcinoma cell (HeLa) lysates. A significant difference between the telomerase negative cells (BHK) from HeLa cells, which was used for qualitative and quantitative detection of telomerase. An almost a linear correlation with the protein concentration was obtained with a R 2 value of 0.9621. The linear correlation coefficients (R2) for HeLa and BHK cell lysate obtained by applying Langmuir adsorption model, were 0.9630 and 0.9766, respectively. Telomerase activity was confirmed by stretch-PCR and fluorometric (F)-TRAP within HeLa extracts. The results obtained both with the QCM system developed in this study and F-TRAP method applied is significantly correlated (r = 0.968, p<0.001).

Plasma Polymerized Films for Mass Sensitive Biosensors

“…Conventional methods used during the detection of these markers have some drawbacks arisen from a series of time-consuming procedure requirement and the usage of complex devices including separative techniques coupled to various detectors such as GC, HPLC, MS, UV and etc. when compared with biosensors [6,[8][9]. Additionally, trained personnel are needed to operate time-consuming and complex conventional systems.…”

“…Many polymeric layers such as cellulose acetate, polyurethane, polystyrene, polyethylene amine, polybutyl methacrylate, polyvinyl formal/ethylal, polyvinylalcohol, and polyethyleneimine have been used for the creation of interface for immobilization of bioreceptor [15][16][17][18][19][20][21][22]. Additionally, many coating methods like silanization, immobilization on the pre-coated crystal, entrapment, or cross-linking methods are used to immobilize bioreceptor such as antibody, aptamer and nucleic acids onto the quartz crystal [6,16,[18][19][20][22][23][24]. However, at the end of these techniques, thicker films are obtained on the crystals' surfaces which diminishes performance by mass overload, and create a harsh environment, which reduces biological activity.…”

Highly sensitive gold-overoxidized polypyrrole nanocomposite immunosensor for antitransglutaminase antibody

“…In immunosensor technology, a secondary label is often required to amplify the microscopic changes accompanying the target–analyte complex formation. 2–7 This article describes a simple and direct procedure for construction of a label-free anti-tTG antibody immunosensor. The experimental procedure consists of gold nanoparticles (AuNP) electrochemically deposited 8–10 onto overoxidized polypyrrole (OPPy), which provides a pertinent substrate for binding high amount of protein.…”