1970 Volume 18 Issue 6 Pages 1083-1090
The precipitation reaction of polyacrylic acid (PAA), polymethacrylic acid (PMA), polyvinyl alcohol sulfate (PVS), and polyvinyl alcohol phosphate (PVP) with O-benzoylthiamine disulfide (BTDS) has been investigated as a function of BTDS concentration, molecular weight, acid strength, and neutralization degree of them in aqueous solution. This precipitation reaction was found to be independent of molecular weight as long as the molecular weight is in the high polymer range, but remarkably to vary with BTDS concentration, acid strength, and neutralization degree. The extent of BTDS cation binding increases in the order PMA<PAA<PVP<PVS. On the other hand, the rate of release of BTDS from the polyacid complexes in 0.1N HC1 aqueous solution decreases in the order BTDS-PVP>BTDS-PMA>BTDS-PAA>BTDS-PVS. The blood total thiamine level after oral administration of the BTDS-polyacid complexes into rabbits has also been investigated. The BTDS-PVS complex exhibited sustained blood level, but with the other complexes, sustained blood levels were not observed.
