Nucleic acid immobilization

Nucleic acids. Immobilized polynucleotides can be used to extract nucleic acid binding proteins as well as complementary strands of nucleic acids. 

A typical DNA array fabrication and application process involves three major steps. First, nucleic acids (the capture sequences or probes) are immobilized at discrete positions on surface activated substrates. Secondly, the resulting array is hybridized with a complex mixture of fluorescently labelled nucleic acids (the target), and thirdly subsequent to hybridization, the fluorescent markers are detected using a high-resolution scanning laser that quantifies the interaction. This chapter focuses on the first of these processes and provides the reader with an overview of substrates, surface activation methods and dehvery systems available for nucleic acid immobilization. 

J. Wang, X. Cai, G. Rivas, H. Shiraishi and N. Dontha, Nucleic-acid immobilization, recognition and detection at chronopotentiometric DNA chips, Biosens. Bioelectron., 12 (1997) 587-599. 

Regardless of the type of immobilization, it is now clear that the local environment of the immobilized nucleic acids is a key determinant of their binding activity [5,6]. Optimization of nucleic acid immobilization chemistry can concurrently alter the sensitivity and speed of the particular sensor methodology. Factors such as immobilization density [5,6], interaction with the substrate [7,8] probe nature [2,4,5,9] and sample processing have been demonstrated to have direct effects on the analytical figures of merit. 

Nucleic acid immobilization including preliminary adsorption and desorption studies and then covalent binding... 

The quality and reliability of microarray results largely depend on the quality and consistency of both the substrate and the reagents used to manufacture and process the arrays, but also on the considerable variation in the experimentalist s skills. A number of different substances have been tested as the solid support for nucleic acid immobilization [7,8], but glass slides are generally favored for DNA and oligonucleotide microarrays [9-11]. Optimal... 

The nucleic acid immobilization chemistry involved is detailed and presented together with the bead arraying or the bead immobilization systems, respectively. 

Fig. 2 Nucleic acid immobilization, (a) Immobilization of 5 -amino-C6 modified probes onto amino modified beads, (b) Grafting of biotinylated probes after the immobilization of avidin via reductive amination onto sepharose beads (3 xm)...

Fig. 4 Nucleic acid immobilization. Immobilization of 5 -amino-C6 modified probes onto (a) carboxylate modified latex beads (1 im) via carbodiimide reaction and (b) Cyanogen bromide (CNBr) activated Sepharose beads (100 un). (0 cyclic structure, e.g. dicyclo-hexylcarbodiimide)...

Fig. 5 Nucleic acid immobilization onto (a) silica 60 nm particles, (b) amino terminated 0.31 xm latex beads and (c) poly(T) modified Dynabeads . MPTS 3-mercapto-propyltrimethoxysilane. (

Fig. 9 Nucleic acid immobilization onto (a) gold nanoparticles via thiolated probe, (b) 10 nm silica beads via glutaraldehyde reaction...

X.H., Fernandes, J.R., Grant, D.H., Ozsoz, M., Beglieter, A., and Mowat, M. (1997) Mismatch sensitive hybridization detection by peptide nucleic acids immobilized on a quartz crystal microbalance. Analytical Chemistry, 69 (24), 5200-5202. 

Enzyme (and nucleic acid) immobilization This application of NPs is the one that is discussed in the present chapter. Various types of enzymes can be immobilized onto NPs [176]. Functionalization of NPs with co-factors (as NAD+) facilitates the biocatalysis from enzymes that need the presence of a cofactor (as lactate dehydrogenase or glucose oxidase) [188]. 

Okahata Y, Matsunobu Y, Ijiro K, Mukae M, Murakami MK (1992) Hybridization of nucleic acids immobilized on a quartz crystal microbalance. J Am Chem Soc 114 8299-8300... 

Prabhakar N, Singh H, Malhotra BD (2008) Nucleic acid immobilized polypyrrole-polyvinylsulphonate film for Mycobacterium tuberculosis detection. Electroehem Commun 10 821-826... 

Fujita, S. Kagiyama, N. Momiyama, M. Kondo, Y Nishiyauchi, M. Fluorometric detection of substances like nucleic acids immobilized on solid carriers. Jpn. Kokai Tokkyo Koho JP 09152433,1997. 

There is currently a growing demand of genetic information in molecular medicine, or for genotyping of individuals in forensic applications, but also in analytical chemistry applied in particular to the preservation of food safety and environment quality. Typical biosensors consist of a nucleic acid immobilized at discrete positions on surface activated slides and constituting the probe, and a sample in which the target is among a complex mixture of fluorescently labelled nucleic acids. The supramolecular interaction resulting... 

---