Biomedical subjects

Akimitsu Okamoto

Publications and source records attributed to Akimitsu Okamoto.

57 records · Page 4Linked to original sources

PubMed2002

Control of photo-induced drug release by the use of conformational change of DNA.

Photo-induced drug release system which was controlled by triplet quenching using the molecular beacon strategy of photoreactive oligodeoxynucleotides (P-ODN) was developed. The strand ends of P-ODN were modified with a phenacyl ester of biotin and naphthalene as photoreactive group and triplet quencher, respectively. Photoirradiation to P-ODN in the presence of complementary DNA caused an efficient release of biotin. In contrast, the biotin release was suppressed in the absence of complementary DNA by the intramolecular triplet quenching in the stem-and-loop structure of P-ODN.

Base Sequence↗

PubMed2002

Development of electrochemically gene-analyzing method using DNA-modified electrodes.

For electrochemical DNA sequencing, several redox-responsive uridines modified at C5 were synthesized and site-specifically incorporated into DNA. Self-assembled DNA monolayers were prepared on a gold electrode using the dsDNA containing modified uridines. By measuring differential pulse voltammetry (DPV) using DNA-modified electrodes, the electrochemical response was strongly affected by the site of the redox-responsive uridine in dsDNA.

DNA↗

PubMedDate not supplied

A dielectric-sensitive fluorescent DNA probe for monitoring polarities on the interior of a DNA-binding protein.

We report a novel fluorescent nucleobase, (DNC)U, for the mapping of the local dielectric properties around DNA. Fluorescence spectra of the nucleoside d(DNC)U showed a significant shift depending on the solvent polarity. This property was used to determine the dielectric constants of the interior of DNA-binding proteins, such as DNA polymerases. We were able to demonstrate that the DNA-binding region of the Klenow fragment is a lower polarity site, as shown by the blue shift of the fluorescence peak originating from (DNC)U.

Base Sequence↗