Issue 21, 2022

High sensitivity label-free detection of HER2 using an Al–GaN/GaN high electron mobility transistor-based biosensor

Abstract

This work reports rapid, label-free and specific detection of the HER2 antigen using a gallium nitride (GaN) high electron mobility transistor (HEMT). Thiol-based chemistry has been utilized to immobilize the corresponding HER2 antibody in the sensing area of the sensor. The formation of a gold–sulfur complex has been confirmed through Raman spectroscopy, giving a peak at around a wavelength of 260 cm−1. Fourier transform infrared spectroscopy and atomic force microscopy (AFM) also reveal the functionalization of thiol and free carboxylic groups. On-chip enzyme-linked immunosorbent assay has been utilized to confirm immobilization of antibody receptors on the sensing area surface, followed by current–voltage measurement. Morphology of the sensing area using AFM and electrical characterization of the sensor have been recorded before and after each functionalization process step. The sensor shows detection of the HER2 antigen in a broad range of 0.7 pg ml−1 to 10 μg ml−1i.e., (5 × 10−15 to 6 × 10−8 M). A long-time study and reusability aspect of the sensor have also been investigated that show good viability of the sensor. For the first time, a three-binding-site model based on the Langmuir isotherm has been developed for HER2 detection using GaN-HEMTs with three dissociation constants, i.e., 7 × 10−10, 8.8 × 10−11, and 7.2 × 10−9 M, respectively.

Graphical abstract: High sensitivity label-free detection of HER2 using an Al–GaN/GaN high electron mobility transistor-based biosensor

Article information

Article type
Paper
Submitted
14 apr 2022
Accepted
26 aug 2022
First published
29 aug 2022

Lab Chip, 2022,22, 4129-4140

High sensitivity label-free detection of HER2 using an Al–GaN/GaN high electron mobility transistor-based biosensor

S. Mishra, P. Kachhawa, A. K. Jain, R. R. Thakur and N. Chaturvedi, Lab Chip, 2022, 22, 4129 DOI: 10.1039/D2LC00349J

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements