Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Title: Ultrathin Growth of SiO2 Shells on Fluorescent High-Temperature High-Pressure Nanodiamonds Institution: San Jose State University, Department of Chemistry Authors: Andres Arreola, Anida Len, Perla Sandoval, Abraham Wolcott Abstract: Early cancer detection is needed to ensure life-saving cancer therapies can be implemented. Improved diagnostics are important for ovarian and pancreatic cell lines, in which late stage detection is common. We aim to develop new biolabeling and biosensing tools based on high-pressure, high-temperature (HPHT) fluorescent nanodiamonds (FNDs). FNDs are an attractive tool for cancer detection because of their comparable size to antibodies, surface tunability, and lack of photobleaching. Specifically, our goals are to investigate the fundamental properties of FNDs’ surface chemistry using silica functionalization and produce high ND-conjugate yields. Previous work revealed that the surface of oxidized HPHT NDs had an alcohol (-OH) rich surface and silica (SiO2) based chemistry has been used in this study to grow ultrathin shells. Tetraethylorthosilicate (TEOS) is hydrolyzed to Si(OH)4 which leads to a nucleophilic attack by an alcohol groups on the ND surface producing a silyl ether bond (C-O-Si) that primes the surface for further SiO2 growth. Silica shell thickness is controlled by adjusting reaction times. Size and surface features of our particles were determined by dynamic light scattering (DLS) and atomic force microscopy (AFM), while surface characterization was determined by Fourier transform infrared (FTIR) spectroscopy. Further determination of composition will be accomplished through energy dispersive X-ray spectroscopy (EDS). Future work includes grafting polyethylene glycol and amine moieties for colloidal stabilization and bioconjugation to cancer-specific antibodies.