Low-Frequency Ultrasonic Relaxation of β-Cyclodextrin and Adenosine 5'-Monophosphate in Aqueous Solution

Abstract

Nucleotides are the building blocks of nucleic acids and essential for many cellular functions. In this study, ultrasonic absorption spectra of β-cyclodextrin (β-CD) and adenosine 5'-monophosphate (AMP) in aqueous solution were measured over the broad frequency range 0.1-40 MHz with emphasis on the low-frequency range below 1 MHz. Here we show that the interaction of β-CD and AMP complies with a typical spectrum of a single relaxation process. We determined reliable rate (kb) and equilibrium (K) constants and a standard volume change ( V) of the reaction. They are kb = 2.3×10 -6 s -1 , K = 89 M -1 , and  V = 13.8 (10 -6 m 3 mol -1 ), respectively.