Abstract
The thermal effects of pH and salt concentration on the helix—coil transition of Poly A were studied calorimetrically by a modified differential scanning calorimeter (DSC). The transition temperature (Tm) and enthalpy (ΔH) of Poly A in acid solution depend both on pH and on the concentration of NaCl. Tm and ΔH increase with decreasing pH at infinite dilution of salt concentration, and decrease with increasing salt concentration at a definite pH. These results indicate that electrostatic interactions between the negatively charged phosphate group and the positively charged adenine group contribute significantly with decreasing pH.
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Baba, Y., Tanaka, S. & Kagemoto, A. Influence of pH and Salt Concentration on the Helix—Coil Transition of Poly A Determined by a Modified DSC. Polym J 7, 641–645 (1975). https://doi.org/10.1295/polymj.7.641
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DOI: https://doi.org/10.1295/polymj.7.641