Strategies for preparation of oligonucleotide biochips and their applications

In the last few years, DNA-microarray technology has emerged as a powerful tool for gene discovery, detection of mutations, and mapping. Here, we have developed a simple and efficient single-step method for immobilization of phosphoryl-, mercaptoalkyl-, thiophosphoryl- and aminooxyalkylated oligonucleotides onto an epoxylated glass surface. It resulted in higher immobilization and hybridization efficiency in comparison to those obtained with the standard method. The probes immobilized were found to be stable over a range of temperature and pH, suggesting that the chemistry could be used in integrated PCR/microarray devices. Also the immobilized spots were found to be of superior quality in terms of spot morphology, homogeneity and signal reproducibility. The constructed microarrays were successfully used for the discrimination of nucleotide mismatches and detection of bacterial diseases.