Ionic liquids (ILs) are organic salts with low melting point by asymmetric ionic strength between cation and anion. They have been known as promising DNA extraction, separation and preservation agent due to their hydrophilic, hydrophobic interaction with DNA. However, few studies have been performed about how DNA-ILs complexes form and their mechanism. Herein, we present three types of ionic liquids (EMIM-Cl, BMIM-Cl, and OMIM-Cl) change the DNA structure depend on alkyl chain length of ionic liquids. Structural changes of DNA by ionic liquids are observed by Atomic force microscopy, gel electrophoresis, zeta potential and solid-state nanopore technology. The results of AFM show the different structures of DNA, including aggregate, stretching, and bundling shapes in terms of EMIM-Cl, BMIM-Cl, and OMIM-Cl respectively. In DNA translocation experiment, DNA/EMIM-Cl show rare translocation signal due to aggregated structure by neutralized surface charge. DNA/BMIM-Cl and DNA/OMIM-Cl show slowing down the translocation speed due to changes of DNA net charge and structure. Especially, OMIM-Cl make slowing down the DNA translocation speed about 102~104 times compared to translocation speed of bare DNA by unzipping the bundling shape of complex. In conclusion, the morphology of DNA could be modified by the incorporation with different alkyl chain length of ILs, providing their further application in nanopore technique for slowing DNA sequencing or understanding protein-DNA interaction.

The syntheses of urocanic acid esters was optimized, starting from p-toluenesulfonic acid salt of this acid and long chain fatty alcohols in the organic solvent and extracting water from it by means of azeotropic Compound. The salts of these urocanic acid esters showed amphoteric properties, but their micellization enhances their rate of hydrolysis leading to the free amine. Nevertheless the long chain gives to the esters themselves an amphoteric character allowing their solubilization in micellar media and in microemulsions the result, yield could enhanced.

1, 2-Isopropylidene glycerol produced by ketalyzation of glycerol with aceton was esterified with long chain fatty acids in the presence of a Mucor miehei lipase to obtain 1, 2-isopropylidene 3-long chain acyl glycerol. To determine optimal conditions for the esterification reaction, esterification was proceeded as a reversible second-order reaction in various parameters that are enzyme<SUB>strate ratio 0.096g</SUB>g at reaction temperatures ranged from 25℃ to 70℃. The order of reaction rate of fatty acids were lauric acid, myristic acid, oleic acid, and stearic acid. The range of their activation energies were from 7.8 to 11.4 (kcal/mol) and that of entropies of activation which have negative values were from 42.8 to 52.5(e.u.).

Hazadous properties were evaluated for Alkyl nitrates such as hexyl nitrate, decyl nitrate, dodecyl nitrate and 2-methyl pentyl nitrate, 2-hexyl ethyl nitrate. The thermochemical properties such as heat of vaporization, boiling point, flash point and kinetic parameter for aliphatic nitrate were measured to determine the hazadous properties of these compounds. The boiling points and heat of vaporization increase as the increase of alkyl chain length in alkyl nitrates. Flash point is a linear function of boiling point as same as alkanes. The rate equation in isothermal decomposition are 1/2 order and compensation effect is found between logarithm of frequency factor the activation energy, then the decomposition preceeds with simlar reaction mechanism for each nitrate.

Aliphatic aldehyde polyoxyethylene glycol acetals were synthesised through the reaction of aliphatic aldehydes such as caproic aldehyde, capryl aldehyde, capric aldehyde and lauric aldehyde with excess diethylene glycol, triethylene glycol and tetraethylene glycol, respectively. The acetal formation, in which water was azeotropically distilled by adding benzene to the reaction system, was gained a good yield of acetal type compounds. This reaction is found pseudo first order reaction at various temperatures such 70, 80, 90 and 97℃. Also these activation energies of reaction of acetal type products such as caproic aldehyde diethylene glycol acetal, capryl aldehyde diethylene glycol acetal, capric aldehyde diethylene glycol acetal, lauric aldehyde diethylene glycol acetal, caproic aldehyde triethylene glycol acetal and caproic aldehyde tetraethylene acetal were 17.3, 19.6, 21.2, 21.6, 15.5 and 14.7 Kcal/mole.