Dong June Ahn

Oligonucleotide assisted tri(8-hydroxyquinoline) aluminium (Alq3) microrods were prepared for the first time. When hybridized with oligonucleotide labeled by Cy3 fluorescent dye, a significant photoluminescence variation of the Alq3 microrods was observed due to Förster resonance energy transfer, unlike when Cy5-oligonucleotide was used. Versatile nucleotide manipulation would open up wider applications of Alq3-based materials, based on this fundamental observation.

The interactions between the surface of scaffolds and specific cells play an important role in tissue engi neering applications. Some cell adhesive ligand peptides including Arg-Gly-Asp (RGD) have been grafted into polymeric scaffolds to improve specific cell attachment. In order to make cell adhesive scaffolds for tissue regener ation, biodegradable nonporous poly(L-lactic acid) (PLLA) films were prepared by using a solvent casting technique with chloroform. The hydrophobic PLLA films were surf

Polydiacetylene (PDA)/poly (vinyl alcohol) (PVA) hybrid films are investigated for detection of ammonia gas generated by the food spoilage process. The films were obtained by mixing solutions containing diacetylene vesicles and aqueous PVA, and then drying. The films, which consist of carboxylic-acid-terminated PDA, showed a blue-to-red color transition upon reaction with ammonia gas. Through Fourier transform infrared (FTIR) analysis, we found that the observed color transition resulted from an

Five different shapes of magnesium hydroxide (Mg(OH)2) particles (Plate-S, Plate-N, Disk, Whisker, and Fiber) were synthesized and added to biopolymer (i.e., Poly(lactic-co-glycolic acid) (PLGA)) composite to improve their mechanical and biological properties. The PLGA composite films including Mg(OH)2 particles were prepared by a solvent casting method. Their mechanical and biological properties were compared according to the composites containing different shapes of Mg(OH)2 particles. Among th

Two kinds of magnesium hydroxide (Mg(OH)2) rods (Mg-Rod, 150 and 350 nm in size) and plates (Mg-PL,60 and 300 nm) were prepared, and blended with poly(L-lactide) (PLLA) to obtain PLLA/Mg(OH)2 composites toinvestigate the effect of the shape and size of Mg(OH)2 particles. The structure, morphology, pH change, thermaland mechanical properties, cytotoxicity, and inflammation of Mg(OH)2 control and PLLA/Mg(OH)2 compositeswere evaluated. PLLA/Mg-Rod150 (30%) composite showed a 50% higher tensile stre

A novel protein recognition platform is developed using aptamer-linked polythiophene nanowires. As the aptamer functionalized poly (3-methylthiophene) nanowire is treated by the specific protein, resonance Raman and photoluminescence signals are simultaneously enhanced. Statistical analyses deliver the capability of a single conjugated polymer nanowire with phase-transition characteristics in response to selectivity and concentration.

High-performance materials for flameproofing, phosphates (polyphosphate and ammonium phosphate) were synthesized on viscose rayon felt. This surface reaction has the advantage of a nonblooming effect and an application in thermosetting plastics. Metal complexes have the effect of reducing the amount of smoke. Therefore, in the second step, transition-metal complexes were synthesized on the viscose rayon ammonium phosphate felt. This article focuses on the surface modification of phosphates and m

The polydiacethylene (PDA) is known to change its color by mechanical shear. The shear-induced color transition has been reported with elastomer or film type of PDA. In this paper, we newly investigated the transition with liposome type of PDAs in polymeric solutions. The liposomes were dispersed in Poly(vinyl alcohol) 2%+Sodium borate 1%, Poly(vinyl alcohol) 15% and Hyaluronic acid 1% (PVA/B, PVA, HA). The shear stress was continuously imposed to each solution by stress control type rheometer w

Hydrogel-based sensory structures were developed by embedding polydiacetylene supramolecules into poly-(ethylene glycol)-diacrylate (PEG-DA) to detect chemical gases and cyclodextrin and to determine pH values on the basis of a fluorescence change. We found the optimal condition for patterning-fabrication by controlling the volumetric mixture ratio of the water-soluble PEG-DA and aqueous polydiacetylene vesicle solution. Then, we determined that this hydrogel-based polydiacetylene structure opti