Dielectrophoresis-Based Protein Enrichment for a Highly Sensitive Immunoassay Using Ag/SiO2 Nanorod Arrays
| Autor: | Zhen Cao, Junxue Fu, Yang Liu, Fan Bai, Yu Zhu, Shengxin Song, Xin Chen, Shurong Dong |
|---|---|
| Rok vydání: | 2018 |
| Předmět: |
Detection limit
Chromatography Materials science Nanostructure medicine.diagnostic_test biology 010401 analytical chemistry 02 engineering and technology General Chemistry Dielectrophoresis 021001 nanoscience & nanotechnology 01 natural sciences Fluorescence 0104 chemical sciences Biomaterials Immunoassay Electrode medicine biology.protein General Materials Science Nanorod Bovine serum albumin 0210 nano-technology Biotechnology |
| Zdroj: | Small. 14:1703265 |
| ISSN: | 1613-6810 |
| DOI: | 10.1002/smll.201703265 |
| Popis: | A nanoscale insulator-based dielectrophoresis (iDEP) technique is developed for rapid enrichment of proteins and highly sensitive immunoassays. Dense arrays of nanorods (NDs) by oblique angle deposition create a super high electric field gradient of 2.6 × 1024 V2 m-3 and the concomitant strong dielectrophoresis force successfully traps small proteins at a bias as low as 5 V. 1800-fold enrichment of bovine serum albumin protein at a remarkable rate of up to 180-fold s-1 is achieved using oxide coated Ag nanorod arrays with pre-patterned sawtooth electrodes. Based on this system, an ultrasensitive immunoassay of mouse immunoglobulin G is demonstrated with a reduction in the limit of detection from 5.8 ng mL-1 (37.6 pM) down to 275.3 fg mL-1 (1.8 f M), compared with identical assays performed on glass plates. This methodology is also applied to detect a cancer biomarker prostate-specific antigen spiked in human serum with a detection limit of 2.6 ng mL-1 . This high sensitivity results from rapid biomarker enrichment and metal enhanced fluorescence through the integration of nanostructures. The concentrated proteins also accelerate binding kinetics and enable signal saturation within 1 min. Given the easy fabrication process, this nanoscale iDEP system provides a highly sensitive detection platform for point-of-care diagnostics. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Plný text