Discipline: Nanoscience
Subcategory: Materials Science
Monique Farrell - Norfolk State University
Co-Author(s): G. Rutherford and A. K. Pradhan, Center for Materials Research, Norfolk State University, Norfolk, VA
Aggregation of gold nanoparticles in gold colloidal solutions can be induced via the introduction of an aminosilane or a change in pH and may affect the stability and optical properties of these nanomaterials. Specifically, methodical changes in the absorbance spectra can be exploited as a visible detection method for target anayltes. To decrease costs associated with medical diagnostics, visual methods of detection that do not rely on large instrumentation and analysis are needed. Therefore, this paper preliminarily investigates the possibility for visual biosensing of bovine serum albumin utilizing concentration dependent induced aggregation of gold nanoparticles via 3-aminopropyl triethoxysilane. Large systematic red shifts in the absorbance spectra of gold nanoparticles coupled with bovine serum albumin in the presence of the aminosilane were observed. These shifts correspond to visual color changes in the solution as a function of the protein concentration. Photoluminescence emission intensity increases as a function of the concentration of protein present in solution, when exposed to the aminosilane. Morphological studies attribute the changes observed in absorbance due to aggregation of samples as opposed to particle growth. Dynamic light scattering results indicate micron scale aggregation in samples that produced visual color changes. Utilizing this method, the visual detection of 4.6E-10 M bovine serum albumin was observed. Preliminary studies suggest a simple and yet effective in solution detection method of biological analytes that inhibit aggregation of gold nanoparticles.
Not SubmittedFunder Acknowledgement(s): This work is supported by the NSF-CREST (CNBMD) Grant number HRD 1036494 and NSF-IGERT.
Faculty Advisor: Aswini Pradhan, apradhan@nsu.edu