THE INFLUENCE OF PVA.cl.CITRIC ACID/CHITOSAN MEMBRANE HYDROPHICILITY ON THE TRANSPORT OF CREATININE AND UREA

Abstract

The influence of cross-linking and membrane hydrophilicity on the transport rate had been studied using a membrane prepared from a mixture of chitosan/PVA cross-linked citric acid (PVA.cl.CA) for creatinine and urea transport. The optimum mole ratio of PVA:citric acid as well as the best composition of chitosan:PVA.cl.CA were determined using creatinine transport study. Using the optimum compositions, further study was done using different thickness of the membrane in transporting creatinine, urea and a mixture of 3 species (creatinine, urea and vitamin B 12

Preparation of Citric Acid Crosslinked Chitosan/Poly(Vinyl Alcohol) Blend Membranes for Creatinine Transport

“…This value relates to the ability of water to diffuse to all parts of the membrane. In other words, in the thin membrane, all parts of the membrane were able contact/interact rapidly with water in a certain period of time, so that the wetting of the membranes occured not only on the surface but also the inside part of the membrane [3,12,16]. Water absorption test was performed to predict the size of the substance that can diffuse through the membrane material.…”

“…In addition, cyanocobalamin has several C=O groups able to form hydrogen bonds with the the active sites of the membrane. The hydorgen bonds indirectly interfere with the binding process of creatinine by the active sites of the membrane [3,10]. In other words, there is a competition between cyanocobalamin and creatinine when approaching the membrane surface, which is likely to be the cause for the decrease of the transport percentage of creatinine.…”

“…According specific interaction between urea and creatinine with reactive groups membrane is dominated by hydrogen bonds. In addition, appropriate ratio of hydrophilic and hydrophobic groups as well as the reactive groups charge orientation are among important factors in hemodialysis membranes [3][4].…”

“…Some of the common strategies for this modification include changing the charge of the active sites, attaching active groups onto the membrane as well increasing membrane hydrophilicity. The three modifications can be carried out reached by grafting, crosslinking s as well as blending with other polymers [3,7,[11][12].…”

“…Not all polymers and biopolymers can be used as membrane, as only polymers capable of forming flexible thin layer films and swelling can be used as the base material for membrane synthesis. In order to improve the mechanical strength of the citric acid crosslinked chitosan membrane, in this study we made blends materials with more hydrophilic polymers such as poly(vinyl alcohol) [3,10,14]. This blends membranes were investigated by tensometer, thickness meter, EA and FTIR.…”