Scanning electrochemical microscopy (SECM) experiments were undertaken to study the EC’mechanism, e.g. where a product of the electrode reaction reacts to regenerate the starting material. Digital simulations of the two dimensional SECM were carried out and the results tested with the known EC’ system of Fe(CN)6 / cysteine for validation. The results were then used in SECM experiments with Ru(p...

In this report, we demonstrate that self-aggregation is an intrinsic problem of bifunctional organocatalysts, especially in the case when the substrates do not have functional groups which are able to bind strongly with catalyst. Due to their self-association phenomena, the enantioselectivity of bifunctional catalysts dramatically decreases with increasing catalyst concentration or decreasing t...

DNA threading intercalators are a unique class of intercalating agents, albeit little biophysical information is available on their intercalative actions. Herein, the intercalative effects of nogalamycin, which is a naturally-occurring DNA threading intercalator, have been investigated by high-resolution atomic force microscopy (AFM) and spectroscopy (AFS). The results have been compared with t...

A nonlabeling voltammetric detection method for DNA hybridization has been developed, in which [Fe(CN)(6)](3-) in solution can readily approach an electrode surface covered with a charge-compensated DNA duplex layer and thus provides a strong redox-sensing current. Charge compensation for negative charges on the DNA backbone has been specifically accomplished on DNA duplexes by discouraging non...

HL-60/AMSA is a human leukemia cell line that is SOto 100-fold more resistant to the cytotoxic actions of the topoisomerase II-reactive intercalator amsacrine than is its drug-sensitive 111-hi) parent line. Previously, we have shown that the topoisomerase II from HL-60/AMSA is also resistant to inhibition by amsacrine and other intercalating agents. We therefore sought the molecular basis for t...

During replication and recombination, two DNA duplexes lie side by side. We have developed reagents that might be used to probe structure during these critical processes; they contain two intercalating groups connected by a rigid linker that forces those groups to point in opposite directions. If their stereochemistry proves appropriate, such structure-specific agents should intercalate specifi...

Introduction: Owing to its optimal nuclear properties, ready availability, low cost and favorable dosimetry, Tc continues to be the ideal radioisotope for medical imaging applications. Most of the bifunctional chelators reported for Tc complexation, suffer from tedious labeling protocols and undesired physicochemical properties. On the other hand, bifunctional chelators based on tetraamine fram...

The design, synthesis, and catalytic application of a highly enantioselective and indefinitely stable polymer-supported Cinchona-based bifunctional sulfonamide is reported.

A new class of bifunctional organocatalyst promotes the chemoselective reduction of diketone electrophiles at catalytic loadings in the presence of an inorganic co-reductant.