Biomedical subjects

Kosuke Mukumoto

Publications and source records attributed to Kosuke Mukumoto.

7 recordsLinked to original sources

PubMed2007

Direct modification of mRNA by ferrocenyl carbodiimide and its application to electrochemical detection of mRNA.

Ferrocenyl carbodiimide (1) could be used for the direct labeling of synthetic RNA and expressed mRNA in vitro with the electrochemically active ferrocene moieties. These RNAs modified by 1 could be detected electrochemically coupled with a DNA probe-immobilized electrode. After hybridization of 1.1 Kb mRNA modified by 1 with the DNA probe-immobilized electrode, the peak charge observed by an Osteryoung square wave voltammetry (SWV) measurement correlated well with the concentration of mRNA, having a detection limit at the sub nanogram level.

Carbodiimides↗

PubMed2006

Electrochemical detection of DNase I activity.

DNase I in one microl of the water could quantitate electrochemically with the detection limit of 0.01 units (ca. 20 pg) by using the ferrocenyl oligonucleotide-immobilized electrode prepared by thiolated oligonucleotide and ferrocenyl carbodiimide as a simple labeling reagent of redox unit.

Carbodiimides↗

PubMed2006

Electrochemical SNP detection.

Detection of mismatched base on a DNA duplex, which is important for the search of the heterozygote, achieved by the comparison with the reactivity of ferrocenylcarbodiimide (1) developed by our group. Mismatched thymine base on the 30-meric DNA duplex as a model of SNPs in lipoprotein lipase (LPL) gene, could react with 1 in 20 mM borate buffer (pH 8.5) and 0.1 M NaCl containing 20% DMSO at 37 degrees C. DNA duplex modified by 1 in the mismatched thymine bases could be detected by its shifted migration time in microTAS electrophoresis.

Base Pair Mismatch↗

PubMed2006

Preparation of carbodiimide-terminated dithiolane self-assembly monolayers as a new DNA-immobilization method.

A carbodiimide derivative having a dithiolane part at its terminus was designed and synthesized for use to construct carbodiimide-coated self-assembly monolayers (SAMs) on a gold surface with 6-mercaptohexanol (6MH). When treated with poly(dT), poly(dA), or poly(dA)poly(dT), only poly(dT) was immobilized on the surface of the SAMs through a specific reaction of the free imino moiety of thymine (T) with the carbodiimide moiety. The carbodiimide-covered SAM treated with probe DNA was tested in hybridization with sample DNA. Its hybridization efficiency was estimated by ferrocenylnaphthalene diimide (FND), described previously and the result revealed that the carbodiimide-covered SAM electrode can immobilize a DNA probe through the thymine moiety not involved in base pairing. The resulting electrode was capable of hybridizing with the target DNA, as proven by an increased current response of FND.

Carbodiimides↗

PubMed2005

Investigation of ferrocenyl carbodiimide (FCDI) in the modification reaction of nucleic acids.

Ferrocenyl carbodiimide (FCDI) was allowed to react with thymine or guanine bases of single stranded DNA in borate buffer (pH 9.5) at 37 degrees C for a short period of time. The reactivity of FCDI with the guanine bases was smaller than that with the thymine ones and the prolongation of the reaction time resulted in a lower yield. The reactivity for double stranded oligonucleotide was extremely decreased from that for the single stranded one. One base mismatched double stranded oligonucleotides could react with FCDI, albeit slowly. These results suggested that the reactivity of FCDI was variable depending on the kind of bases and the oligonucleotide structure.

Base Pair Mismatch↗

PubMed2004

Synthesis of ferrocenyl carbodiimide as a novel ferrocenyl reagent of single stranded DNA.

Ferrocenyl carbodiimide (FcCDI) was newly synthesized as a ferrocenylation reagent for single stranded DNA. FcCDI could attach to oligodeoxyribonucleotides (ODN) through a covalent bond with thymine and guanine bases. The reactivity of thymine with FcCDI was higher than that of guanine, but independent of their location on the DNA sequence. After a single stranded DNA was treated with FcCDI, resulting ODN could be detected electrochemically by a redox signal deriving from the ferrocenyl moiety with a DNA probe-immobilized electrode. These results suggest that the labeling of DNA with FcCDI can be applied to rapid analysis of electrochemical genosensors.

Carbodiimides↗

PubMed2003

Development of a novel genosensor based on ferrocenyl oligonucleotides.

Two types of ferrocenyl oligonucleotides, Fc1-ODN and Fc2-ODN, carrying a 5'-ATT GCT CAG GGG TAA GGT CAT TAG TTG GAA-3' sequence were allowed to hybridize with the DNA probe carrying a complementary sequence immobilized on the gold electrode to give rise to a redox signal deriving from their ferrocenyl moieties. When a mixture of these oligonucleotides in a proper ratio was used as a model of DNA samples, two redox peaks were observed in one differential pulse voltammogram. The peak currents varied depending on the initial ratio of the two oligonucleotides, suggesting a possibility that this technique may be applied to electrochemical monitoring of gene expression by, for example, the electrochemical differential hybridization, EDH.

Base Sequence↗