An extended-gate field-effect-transistor (FET) sensor with a gold-sensing electrode, to which a gold-thiol bond could easily be applied, was developed for DNA detection. Because the gold electrode is located in a different area from the FET, it can be operated without a light-shielding box by masking only the FET. However, when the FET sensor is used in an aqueous solution, fluctuation of the i...

We report a strategy for the reagentless transduction of DNA hybridization into a readily detectable electrochemical signal by means of a conformational change analogous to the optical molecular beacon approach. The strategy involves an electroactive, ferrocene-tagged DNA stem-loop structure that self-assembles onto a gold electrode by means of facile gold-thiol chemistry. Hybridization induces...

Pyrene derivatives can be incorporated into nucleic acid analogs in order to obtain switchable probes or supramolecular architectures. In this paper, peptide nucleic acids (PNAs) containing 1 to 3 1-pyreneacetic acid units (PNA1-6) with a sequence with prevalence of pyrimidine bases, complementary to cystic fibrosis W1282X point mutation were synthesized. These compounds showed sequence-selecti...

Nucleic acids contain severa' characteristic structural features: a chiral center adjacent to the base, a stereoregular, hydrophilic poly(phosphate-ribose) backbone which is negatively charged at neutral pH, and a helical secondary structure arising from conformational preferences enforced by base-stacking. We have prepared and studied several synthetic polynucleotide analogs having linear poly...

Kunjin virus is a member of the Flavivirus genus and is an Australian variant of West Nile virus. The C-terminal domain of the Kunjin virus NS3 protein displays helicase activity. The protein is thought to separate daughter and template RNA strands, assisting the initiation of replication by unwinding RNA secondary structure in the 3' nontranslated region. Expression, purification and prelimina...

A series of substituted phenanthridine derivatives has been synthesized by converting the amines at the 3- and 8-positions of ethidium bromide into guanidine, pyrrole, urea, and various substituted ureas. The resulting derivatives exhibit unique spectral properties that change upon binding nucleic acids. The compounds were analyzed for their ability to inhibit the HIV-1 Rev-Rev Response Element...

The sensitivity of PCR for the amplification of target nucleic acid sequences in clinical diagnostics may often be reduced due to the presence of inhibitory factors. Hemolytic serum contains a number of PCR inhibitors, one of which is hemin. In this study we have found that conventional methods of DNA extraction were not sufficient for the removal of PCR-inhibitory compounds in hemolytic serum....

Mutant huntingtin (HTT) protein causes Huntington disease (HD), an incurable neurological disorder. Silencing mutant HTT using nucleic acids would eliminate the root cause of HD. Developing nucleic acid drugs is challenging, and an ideal clinical approach to gene silencing would combine the simplicity of single-stranded antisense oligonucleotides with the efficiency of RNAi. Here, we describe R...

Compounds that are covalent analogues of nucleic acid base pairs of normal, long, and short C1' to C1' dimensions [B. Devadas and N.J. Leonard (1990) J. Am. Chem. Soc., 112, 3125-3135.] have been added to the oligodeoxyribonucleotide d(A)6 with bacteriophage T4 RNA ligase as a prelude to placing them at defined loci within nucleic acid duplexes. Analogue cross sections that represent a normal W...