Study On Synthesis And Adsorption Properties Of Dialdehyde Cellulose-Quaternary Ammonium Salt Of Chitosan Polymer

Urea and creatinine are two kinds of major metabolic products. The removal of their excess has been a major problem for patients suffering from chronic renal failure(CRF). The development of novel oral adsorbents with high adsorption capacity, broad spectrum and little side effect is significant for delaying disease progress. In this paper, DAC-HTCC,which was employed as a new adsorbent for removing urea and creatinine, was prepared by crosslinking DAC and HTCC.Two kinds of quaternary chitosans were synthesized including TMCC and HTCC. They were characterized by IR and 1H NMR. It was indicated by creatinine adsorption experiment that their adsorption capability was obviously better than that of chitosan. With the same degree of substitution(DS), HTCC had more adsorption capacity than TMCC for creatinine. The optimized conditions of HTCC with high DS and creatinine adsorption capability were that the reaction time was 12h, the reaction temperature was 80℃, nCTA/nCTS was equal to 4, mNaOH/mCTS was equal to 1 and the mass of CTA was 35%. The degree of substitution of the product prepared under this condition was 72%. Its maximum adsorption ratio of creatinine could reach up to 51%, and the adsorption capacity was 1.53mg/g. Adsorption equilibrium was formed in 6h for HTCC. HTCC was affected hardly by urea and showed well selectively adsorption capability for creatinine.A new multiplex adsorbent DAC-HTCC was synthesized with EGDE as the crosslinking agent and HClO4 as a catalyst. It was characterized by IR and SEM. The optimized conditions for crosslinking were that mass ratio of HTCC(DS=72%) and DAC(DO=50%) was equal to 1.5, the amount of EGDE was 4 times more than the theoretical amount, the reaction time was 4h and the reaction temperature was 60℃. Adsorption equilibrium was formed in 6h and 8h for absorbing urea and creatinine respectively by DAC-HTCC. Both adsorption capacity increased along with the concentration of urea and creatinine solution. The maximum absorption capacity for urea was 13.98mg/g and that for creatinine was 2.37mg/g. Compared with Coated Aldehyde Oxystarch and Medicinal Charcoal Capsules in urea, creatinine and mixed solution, DAC-HTCC had better adsorption capability for urea and creatinine, which was affected hardly by the existence of both of urea and creatinine.