Liquid-liquid extraction of enzymatically synthesized functional RNA oligonucleotides using reverse micelles with a DNA-surfactant.

We successfully implemented solvent extraction of short, single-stranded RNA using reverse micelles (water-in-oil microemulsions) with a DNA-surfactant. A thrombin-binding RNA aptamer was enzymatically synthesized and purified by extraction using the reverse micellar system. The extracted RNA aptamer retained thrombin-binding activity after the extraction procedure.

Conjugation of DNA with protein using His-tag chemistry and its application to the aptamer-based detection system.

We propose a novel method to prepare a DNA-protein conjugate using histidine-tag (His-tag) chemistry. Oligo-DNA was modified with nitrilotriacetate (NTA), which has high affinity to a His-tag on recombinant protein via the complexation of Ni(2+). Investigations using a microplate which displayed a complementary DNA-strand revealed that a NTA-modified DNA-protein conjugate was formed and immobilized in the presence of Ni(2+) on the microplate.

Sequence-selective extraction of single-stranded DNA using DNA-functionalized reverse micelles.

We report here sequence-specific liquid/liquid extraction of single-stranded DNA using reverse micelles (water-in-oil microemulsions), in which hybridization between a DNA-surfactant and a target DNA having a complementary sequence allows selective transport of the target DNA to an organic phase from a mixture of DNA oligonucleotides.

Masking oligonucleotides improve sensitivity of mutation detection based on guanine quenching.

Guanine quenching of a fluorescence-labeled DNA probe is a powerful tool for detecting a mutation in a targeted site of a DNA strand. However, a different guanine adjacent to a targeted site can interfere with detection of a point mutation, resulting in unsatisfactory sensitivity. In the current study, we developed a simple method to improve sensitivity of the guanine quenching method using a masking DNA oligonucleotide.