Biosensors microarray applications

These conditions are met in most practical situations, in micro- and even nanobiodevice applications. For instance, the high density of DNA molecules is required to increase the sensitivity of the device long DNA molecules are commonly (but not exclusively) used as target molecules in e.g., biosensors, microarrays and microPCR devices single DNA species used as targets translate in lack of complementarity and most substrates, (e.g., glass, polymers) for micro/nanobiodevices are amorphous. The critical difference between the self-assembled and amorphous DNA layers, which leads to the polymerlike character of the latter, is the lack of complementarity between adjacent strands. Still, as with polymers, the DNA chains have to have a consider-... 

Bioresorbable polymers, 3 735-740 Bioselective adsorption, 6 387 Biosensors, 3 794-815 14 154 22 269 affinity DNA biosensors, 3 805-808 affinity immunosensors, 3 800-805 applications, 3 812-813 biomimetic sensors, 3 809-810 catalytic, 3 796-799 cellulose ester applications, 5 408 comparison with microarrays, J6 38It evolution of, 16 380-381 production by thick-film technology, 3 810-812... 

With the increasing interest in and application of DNA and protein microarrays, biosensors, cell surface interactions, and biomedical implants, various systems and strategies for the immobilization and patterning of biomolecules have been developed and some have become well established. A wide diversity of chemical methods for biomolecule immobilization on inorganic substrates has been implemented by different research groups. Often, the choice of the method is a compromise between effectiveness, cost, and technology. In consideration of stability and durability of the attached biomolecules, certainly, the covalent attachment has to be preferred. 

Among numerous reported applications of genosensors for DNA hybridization as few examples, one can refer to a disposable DNA sensor for detection of hepatitis B virus genome DNA,145 biosensor systems for homeland security using DNA microarrays,146 and DNA electrochemical biosensor with conducting polymer film and nanocomposite as matrices for detection of HIV DNA sequences.147... 

C. R., Fabrication and characterization of 3D hydrogel microarrays to measnre antigenicity and antibody functionality for biosensor applications. Biosens. Bioelectron., 20(4), 753-764, 2004. 

The third advantage, the chemical stability of DNA aptamers, can solve the main problem of protein-based biosensors. The chemical and physical instability of protein-based biosensors is always claimed in practical use, and this limits the range of biosensor application. However, DNA is chemically stable. It is stable within the pH range 2 to 12 and is thermally renaturable Even if it is denatured at 100°C, it is refolded at room temperature. Even RNA aptamers can gain stability upon 1 modification therefore, aptamers have the potential to enhance the applicability of biosensors in practical contexts. Additionally, aptamers can be immobilized onto substrates using DNA microarray fabrication technology, and aptamer microarrays can be created. 

In recent years, the microarrays based on killifish complementary DNA (cDNA) and algae Synechocystis cDNA have been constructed in order to evaluate environmental stresses at the levels of genes [53-55]. The application and development of such microarrays (against a variety of environmental pollutants) may result in rapid and easy detection of pollutants. However, such microarray technology requires a lab-based specific device. In order to use it as the DNA biosensor, downsizing of the whole system is required. Success of such downsizing may make it possible to do on-site assessment. 

---