A label-free biosensor based on gold nanoshell monolayers for monitoring biomolecular interactions in diluted whole blood.
Gold nanoshells (GNSs) were self-assembled on the surface of transparent glasses modified with 3-aminopropyltrimethoxysilane (APTES) to form GNS self-assembled monolayers (SAMs). Because the localized surface plasmon resonance (LSPR) of GNSs can be controlled in the near-infrared (NIR) region of the spectrum, where the optical transmission through tissue and whole blood is optimal, GNSs would be used as an effective signal transduction in whole blood. Accordingly, after modified with cystamine and biotin-NHS (N-hydroxy succinimide), GNS SAMs were used as a novel optical biosensor for real-time detection of streptavidin-biotin interactions in diluted human whole blood within short assay time, without any sample purification/separation. An UV-vis-NIR spectrophotometer was used to monitor the absorbance changes at 730 nm as a function of time for different concentrations of streptavidin in 20% whole blood, and the results showed that the biosensor displayed low detection limit of approximately 3 microg/mL and wide dynamic range of approximately 3-50 microg/mL. This approach provides an opportunity to construct LSPR biosensor for protein sensing and cellular analysis in diluted whole blood.
Wang
Yi
Y
State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing, PR China.
Qian
Weiping
W
Tan
Yong
Y
Ding
Shaohua
S
D015374:Biosensing Techniques / Q000295:instrumentation* / Q000379:methods; D001798:Blood Proteins / Q000378:metabolism*; D020099:Coated Materials, Biocompatible / Q000737:chemistry; D004867:Equipment Design; D019544:Equipment Failure Analysis; D006046:Gold / Q000737:chemistry*; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure; D025941:Protein Interaction Mapping / Q000295:instrumentation* / Q000379:methods; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013194:Staining and Labeling; D020349:Surface Plasmon Resonance / Q000295:instrumentation* / Q000379:methods
D001798:Blood Proteins; D020099:Coated Materials, Biocompatible; D006046:Gold