| dc.description.abstract | Personal treatment has been a new medical trend recently. Based on the analysis of gene information, professional healthcare could give every individual a precise medical treatment. From the perspective of clinical diagnosis, if we could combine gene chip technology and a huge gene database, we would obtain the gene information immediately. However, there are still numerous problems in gene chip technology, such as the instability and the cost of fluorescent label, the sensitivity of gene chip. Silicon nanowire field effect transistor (SiNWFET) could be a huge potential for next generation detection platform due to its high sensitivity, label-free technique, and high response time…etc. However, the environmental ionic concentration would influence the sensitivity of SiNWFET when we detect the electronic signals of duplex formation. According to the previous studies in our lab, by neutralizing site-specific phosphate backbone with methyl phosphotriester (MPTE) inter-nucleoside linkage(s), we improved the electronic signals of SiNWFET when DNA/DNA hybridization under low ionic concentration.
The probe density on gene chip which fabricated with spotting method is lower than those fabricated with in situ synthesis that developed by Affymetrix. In order to have a more precise gene information on clinical diagnosis, there must be higher dense probes on microarray, which is called high throughput microarray. Therefore, in this study, we use (R,S)-1-(3,4-methylenedioxy-6-nitrophenyl)ethyl chloroformate (MeNPOC-Cl) as the raw material to develop novel deoxynucleosides for in situ synthesized oligonucleotides, which contain site-specific methyl phosphotriester (MPTE) inter-nucleoside linkage(s), on SiNWFET. Using 2-step nucleophilic reactions, 5’-MeNPOC-2’-deoxynucleoside p-methoxy phosphoramidite can be synthesized and can be qualitative analyzed with 600MHz NMR and ESI-QTOF-MS, but so far, we cannot get the pure products due to their instability. In addition, we characterized these deoxynucleosides by UV spectrum and MASS spectrum after solution phase illumination test, and try to synthesize dinucleotide in solution phase.
Eventually, 5’-MeNPOC-2’-deoxynucleoside p-methoxy phosphoramidite can be synthesized. In the future, if we could improve the purification method for the desired products, we aim to fabricate a high-throughput FET-based DNA microarray with these novel deoxynucleosides by in situ synthesis method and provide a more precise gene information on clinical diagnosis. | en_US |