Abstract
The rates of release of nicotinamide (NAA) from fatty acid (FA)-NAA complexes, FA-NAA, were determined in a JP XI dissolution test apparatus in 500 ml of JP XI disintegration test medium No. 1 at 37°C. The release rate constant (k) and the activation Gibbs energy (ΔG〓) for the release of NAA from FA-NAA were estimated. The results obtained for FA-NAA were compared with previous results obtained for the thiamine disulfide (TDS) complex, (FA)6-(TDS).The plots of log k against the carbon number of the constituent FA (n) presented a zig-zag line which indicates a downward convex at an odd-numbered position. The plots of ΔG〓 against n showed a zig-zag line with an upward convex at an odd-numbered position, though the positive value of ΔG〓 increased rather regularly with an increase of n for either even-numbered or odd-numbered FA.The phonomena that the plots of log k vs. n and ΔG〓 vs. show zig-zag lines due to the difference between even- and odd-numbered FA were the same as observed previously for the relase of TDS from (FA)6 (TDS).
