Physicochemical Study of the Interaction of Some Water Soluble Vitamins with Veegum

ABSTRACT. The interact ion of some water soluble vitamins -thiamine hydrochloride, riboflavin, nicotinarnide, pyridoxine hydrochloride and ascorbic acid with a xmntnlorillonite clay (Vecgum) has been investigated. The data obtained from the interactive studies fitted well on the isothermal equilibrium adsorption-tikc plots. Th3 results were analyzed using the Langmuir's equatim The Langmuirs p!3t yiclded reasonable linearity fiom which interactive constmts were ca!cc!atx!. The theoretical maxixnum intcractivc capacity of Vccgum for each of the vitamins, that is, the b-factor in nigl~, was cakulatecl to be 21.69, 19.50, 13.67, I5.W and 3.38 rcspcctively. T1x inf?tlc,:::: of some pl~ysicochemical factors such as temperatnrc, pI-I, clcctrof;:~~ 2nd dickctric constant of the reaction mcdium and thc prcscncc of a prcservalive was equally eximircd, When comparcd with tlic in:crr;ctior, ofmo~~tli;cri!lo,zite clays with other drugs, the resuIts ofthis study il:bica:c tht Vcegm cx!lib?~ed nfilinlal interaction with the vitamins studicd and they appcar :d ickract ~tiononlolecularly. The patterns of the n~onolaycr kternction were modified by the various physicochen~ical parameter studied. For examp!e, increase in the concentration of sodium chloride or calcium chloride, increased the interactive potentials of Veegum for pyridcxine hpdroch!oride and nicotinanlide but decreased the interactions of thiamine hydrocldoride, riboflavin and ascorbic acid with Veegum. The interactions of the vitamins with Veegum were also dependent on temperature charges, presence of a preservative, pH and dieIectric consta~t of tke reaction nediurn The results showed that Veegum could be used as a viscosityenhancing agent in the solution of scii~c watcr sol~blc vitamins without a significant loss of the vitaiis duc to ktcrazthi -i;i!h the cky.