Ultra-sensitive protein detection based on nanoparticles embedded on polymer brush

• Main Author: Genji Srinivasulu, Yuvasri
• Other Authors: School of Chemical and Biomedical Engineering
• Format: Theses and Dissertations
• Language: English
• Published: 2014
• Subjects: DRNTU::Engineering
• Online Access: http://hdl.handle.net/10356/61112
• Institution: Nanyang Technological University

The ultra-sensitive protein detection is the major need of today‟s bioworld as protein serves as the biomarker of existing or newly developing diseases. Many advancements are made in the field of proteomics and clinical diagnostics towards protein detection and one such advancement is the use of nanotechnology. Nanoparticles used for biomolecular detection is mainly due to its size and unique properties. With higher historical importance, gold nanoparticles are mostly used in the sensing platform and act as an excellent scaffold for the fabrication of novel biological sensors. The majority of nanoparticle-based colorimetric protein detection are done in the solution phase. But there arises several drawbacks of solution phase diagnostic methods including the aggregation of nanoparticles, non-specific interaction with non-target molecules and lack of sensitivity for the coloured samples. To avoid these, physical immobilization of nanoparticles on a solid substrate found to be a better alternative.Though solid phase detection prevents aggregation of nanoparticles , formation of protein corona blocks its ultra-sensitivity and specificity of detection. To overcome this problem, many works are done to immobilize nanoparticles on non-fouling polymer brush, which serves as a stable solid platform for ultrasensitive protein detection. POEGMA found to be superior from other types of anti-fouling polymer brush because of its biocompatibility, thermo-responsive behavior and extreme mechanical and chemical robustness. Thus, implemented a novel and unique strategy of cluster formation of small sized nanoparticles that are embedded on POEGMA polymer brush for femtomolar detection of protein in undiluted human serum. The objective of this study is to see how heating can trigger the formation of cluster and how that can be used for ultra-sensitive detection. From various trials, obtained lower limit of detection with higher dynamic range and good ultra-sensitivity of the sensor at much reduced cost.