Cantilever nanobiosensor using tyrosinase to detect atrazine in liquid medium

Abstract

The aim of this study was to develop a cantilever nanobiosensor for atrazine detection in liquid medium by immobilising the biological recognition element (tyrosinase vegetal extract) on its surface with self-assembled monolayers using gold, 16-mercaptohexadecanoic acid, 1-ethyl-3-[3-dimethylaminopropyl] carbodiimide hydrochloride/n-hydroxysuccinimide. Cantilever nanobiosensors presented a surface compression tension increase when atrazine concentrations were increased, with a limit of detection and limit of quantification of 7.754 ppb (parts per billion) and 22.792 ppb, respectively. From the voltage results obtained, the evaluation of atrazine contamination in river and drinking water were very close to those of the reference sample and ultrapure water, demonstrating the ability of the cantilever nanobiosensor to distinguish different water samples and different concentrations of atrazine. Cantilever nanosensor surface functionalization was characterised by combining polarisation modulation infrared reflection-absorption spectroscopy and atomic force microscopy and indicating film thickness in nanometric scale (80.2 ± 0.4 nm). Thus, the cantilever nanobiosensor developed for this study using low cost tyrosinase vegetal extract was adequate for atrazine detection, a potential tool in the environmental field.

Beyond biology: alternative uses of cantilever-based technologies

“…This system worked also for detecting atrazine, the second most used herbicide, an environmental contaminant and a xenobiotic. 185 In this case, although the atrazine detector was developed by the same approach, the cantilevers were functionalized with tyrosinase, extracted from bananas. Similarly, synthetic hapten conjugated with bovine serum albumin (BSA) was covalently immobilized onto a cantilever to detect dichlorodiphenyltrichloroethane (DDT).…”

Mathematical Model of a Nanosensor Based on Optical Tweezers

“…To fulfill condition (19) at n = 2.3, n0 = 1.33 and T = = 293 K, the laser radiation power (in watts) must be related to the particle radius (in meters) by the ratio 24 3 1, 3 10 P a − ≥ ⋅ . For a = 10 nm, a power P = 1.3 W is required, and for 100 nm -1.3 mW.…”

“…In one of the first, if not the first, optical nanosensors, a nanoparticle moved with optical tweezers was associated with fluorescein, and it was determined from the shift of its fluorescence spectrum that the pH of water is different near the wall of a glass vessel and in-depth [12]. In later versions of optical nanosensors, in addition to fluorescence, the violation of the total internal reflection of light and the formation of an evanescent field [13,14], localized surface plasmon resonance [15,16], surfaceenhanced Raman light scattering [17,18], and opticalmechanical phenomena [19,20] began to use.…”

Cantilever Nanobiosensor Functionalized with Tyrosinase for Detection of Estrone and β-estradiol in Water

“…2c) showed groupings with irregularities, being more abundant in EDC/NHS layer. As 16-MHD acid has a long-chain molecule [15,16], its deposition increased the surface roughness. This increase was also observed when the mixture of EDC/NHS crosslinking agents was added and occurred due to the changes in the functional groups exposed on the surface.…”