Surface-initiated reversible polymerization of self-primer oligonucleotides

Abstract

I. Surface-Initiated Reversible Polymerization of Self-Primer Oligonucleotides Due to its coding nature, the many chemical and enzymatic manipulations that it can undergo, and its relative stability, DNA is being used as a bio-chip and microarrays. In this paper, a reproducible method for depositing and immobilizing DNAs of interest on a supporting gold substrate is discussed. The mercapto haxanol (MCH) and HS-ssDNA mixed SAM were carried out to orient the HS-ssDNA perpendicular to the surface. Four types of HS-ssDNAs were acted as self-primer to accelerate overall reaction rate by skip a precursor oligonucleotide formation process in the enzymatic reaction. The polymerization reactions were achieved using Taq DNA polymerase. The d(GCGC) and d(CATG) were performed the polymerization step with TMAC and DMSO to block the aggregation of between charged DNA side chains. The results of digestion process indicate that specific restriction enzymes can digest specific DNA sequence through recognition of specific sequence of DNA polymer. The cleaved DNA strands were again elongated in the same condition of polymerization step. The results of every process were characterized using atomic force microscopy (AFM), contact angle, and Ellisometry. The results suggest that the DNA polymer film would be used reversible biotechnology and modified by functionalization of DNA polymers to change the property of the DNA-tethered surface. II. Formation of λDNA-Templated Porous Silver Shell Here, we report a formation method of DNA-templated porous silver shells via bottom-up approach. The porous silver shell was fabricated via three-step reaction. First, the λDNAs were electrostatically adsorbed onto a glass bead surface by Mg2+ ion bridges. This Mg2+ ion was also acted as a masking ion to reduce nonspecific silver deposition in the metallization step. Second, after the attached λDNAs on the glass bead were crosslinked by UV light (254 nm), silver ions (Au(I)) were electrosta...