Biomedical subjects

Ju Han Bok

Publications and source records attributed to Ju Han Bok.

3 recordsLinked to original sources

PubMed2005

A fluoride-selective PCT chemosensor based on formation of a static pyrene excimer.

[reaction: see text] Calixarene-based fluorescent chemosensor 1 with two fluorogenic pyrene units conjugated to amide groups as guest recognition sites is synthesized. Complexation of F(-) by 1 causes a red shift of its absorption band to 400 nm (Deltalambda = 54 nm) and a blue shift of the excimer emission to 470 nm (Deltalambda = 12 nm) together with enhanced fluorescence intensity. The blue-shifted excimer emission is attributed to a pyrene dimer formed in the ground state, a so-called static excimer.

Calixarenes↗

PubMed2005

An excimer emission approach for patterned fluorescent imaging.

Selective removal of t-Boc protecting groups in a polymer film imbedded, pyrene-containing calixarene derivative results in the generation of a patterned fluorescence image without employing wet developing processes.

Journal Article↗

PubMed2004

A series of tetrahomodioxacalix[4]biscrown-n. Syntheses, crystal structures, and metal binding abilities.

A series of novel tetrahomodioxacalix[4]biscrowns with crown-2, crown-3, crown-4, crown-5, and crown-6 units were synthesized. Conformations of each product are dependent on the base used and their conformation stabilities. All conformations were proven by NMR spectra and/or X-ray crystal structures. The 1,3-alternate homodioxacalix[4]biscrown-4 (4b) shows the best selectivity for K+, whereas the 1,3-alternate homodioxacalix[4]crown-5 (5) does for Cs+. Those selectivities are attributable to electrostatic interaction between the metal ion and the crown ring, as well as a pi-metal complexation. However, the C-1,2-alternate conformation does not take the metal ions regardless of the crown species as a result of steric hindrance from the methylene bridge of an ArCH2Ar unit.

Journal Article↗