Effects of the Biomolecules: Vitamins, Proteins, Amino Acids, and Surfactants: DTAB, MTOAC, TMSOI, Orcinol on Upper Critical Solution Temperatures

Authors : Man SİNGH, Vinod KUMAR

Pages : 121-133

View : 37 | Download : 11

Publication Date : 2007-09-01

Article Type : Conference Paper

Abstract :Upper critical solution temperatures insert ignore into journalissuearticles values(UCSTS ± 0.05 K); and mutual solubilities of phenol + water systems are reported separately with 0.5 millimol kg-1 insert ignore into journalissuearticles values(mm kg-1); proteins insert ignore into journalissuearticles values(casein, pepsin, egg-albumin);, vitamins insert ignore into journalissuearticles values(B1-thiamine, B2-riboflavin, B6-pyridoxine);, amino acids insert ignore into journalissuearticles values(glycine, β-alanine, L-leucine); and surfactants insert ignore into journalissuearticles values(dodecyl trimethylammonium bromide- DTAB, trimethylsulphoxonium iodide-TMSOI, methyltrioctylammonium chloride- MTOAC, orcinol);. The additives decrease the UCSTs by about 0.50-2 0C with slight enhancement in mutual solubilities but the leucine with two –CH3 insert ignore into journalissuearticles values(methyl); and two - CH2- insert ignore into journalissuearticles values(methylene); groups produce negligible increase in the solubilities. The –CH3 and - CH2- groups develop stronger hydrophobic interactions but the glycine develops stronger hydrophilic interactions due to –N+H3 insert ignore into journalissuearticles values(amino); and –COO- insert ignore into journalissuearticles values(carboxylic); groups and weaker hydrophobic due to single –CH2- group. The leucine increases the solubility by 0.009 mole fractions with a 0.7 0C decrease in USCT as compared to phenol-water. The mole fractions of additives restricted to 0.002 to 0.005 range, the conjugations of casein and vitamins in place of –CH3 groups of amino acids enhance the solubility with lower UCST values.
Keywords : DTAB, TMSOI, critical solution, surfactant, hydrophilic interaction, hydrophobic interaction, upper critical solution temperature

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