An Organic Nanoparticle based High Signal Amplification Immunoassay with Improvement of Nonspecific Binding
- *Corresponding Author:
- Yuan-Cheng Cao
Key Laboratory of Optoelectronic Chemical Materials and Devices of Ministry of Education
Jianghan University, Wuhan 430056, China
Tel: 0086 (0) 27 5125 3048
E-mail: [email protected]
Received Date: April 07, 2014; Accepted Date: June 13, 2014; Published Date: June 17, 2014
Citation: Wang Z, Yuan-Cheng C (2014) An Organic Nanoparticle based High Signal Amplification Immunoassay with Improvement of Nonspecific Binding. J Nanomed Nanotechnol 5:207. doi:10.4172/2157-7439.1000207
Copyright: © 2014 Wang Z, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
A high signal amplification immunoassay method based on Fluorescein Diacetate (FDA) organic nanoparticle was proposed here. FDA nanoparticles were prepared in a ball mill and centrifugation was applied to get the size-uniformed SDS stabilized particle ([email protected]). Further SEM images confirmed the particle size was well dispersed in solution and particle size analysis results showed that the particle size 90% was distributed in the range of 200 nm to 500 nm. Mass Spectrometry results showed that the antibody can directly attach to the [email protected] particles and standard sandwich immunoassay confirmed the bioactivity of the antibody on the [email protected] particle surface ([email protected]). And then Zeta potential test results showed that the blocking reagents BSA and Casein can successfully block the unsatisfied sites on the [email protected] surface, which resulted in the improvement of nonspecific binding and stabilization. Further experiments were carried out using the standard immunoassays which showed the analyte signal can be greatly amplified when Casein was used as block buffer in the immunoassays. The limitation of detection was lower than 10 pg/mL, which is 100 times lower than Cy3 or FITC directly labeled antibody. The improved procedure simplifies previously reported protocols and provides a simple high signal amplification immunoassay.