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The subject is the Doctoral Program of Higher Specialized Research Fund project (project number: 20060225008) and Northeast Forestry University graduate thesis funded project (j2am02). Chronic renal failure (chronic renal failure, CRF) is a clinical syndrome, the main cause of the patient's body gathered in two main toxins - urea, creatinine. Therefore the removal of excess toxins in the body is the key to the treatment of chronic renal failure, the oral adsorbent is one of the effective means of treating chronic renal failure. In this study, carboxymethyl cellulose as a carrier, has developed a series of carboxymethyl cellulose derivatives: oxidized carboxymethyl cellulose, the picric - Carboxymethyl cellulose ester, picric - oxidized carboxymethylcellulose ester , as the oral adsorbent of a novel composite target of the treatment of chronic renal failure is applied to the adsorption of urea and creatinine, and its stability and adsorption was compared, at the same time important substances in the body of vitamin B6 The adsorption properties were determined. The results are as follows: to the acidification of the sodium carboxymethylcellulose (CMC) as the raw material, oxidizing agents have optional feature of sodium periodate. The oxidized carboxymethylcellulose prepared under acidic conditions, using FTIR, XRD, DSC and elemental analysis and chemical functional groups (alkali fusion measured aldehyde content) was measured by means of the structure of the oxidized carboxymethylcellulose carried Characterization The results show that the oxidation of CMC has been generated. The effects of the reaction temperature, reaction time, materials ratio and reaction medium pH value on the adsorption of urea. Through the determination of recoveries, the best solvent of the reaction is determined, and studied the relationship between the the oxidized carboxymethylcellulose aldehyde content and adsorption capacity of urea, and the adsorption equilibrium of the oxidized carboxymethyl cellulose to urea and kinetic curves. Experimental results show that the sodium periodate oxidation CMC quality ratio of 4:1, the reaction temperature is 50 ° C, the reaction time of 3h, the reaction medium at pH 2, the solvent is ethanol, this time aldehyde content of 85.23%, a yield 90.5%. Under simulated physiological conditions, adsorption temperature 37 ℃, adsorption medium at pH 7, the maximum adsorption capacity of urea 38.60mg / g. Adsorption equilibrium time of 6h. The adsorption isotherm meet Freundich equation. Using thermodynamic functions calculate the the oxidized carboxymethylcellulose urea equivalent adsorption enthalpy of adsorption free energy and adsorption entropy, the oxidation of carboxymethyl cellulose adsorption of urea mainly for chemical adsorption endothermic process. Prepared picric carboxymethyl cellulose esters (CMC-PA) to carboxymethyl cellulose (CMC) and picric acid (PA) as the raw material, the conditions are mild and the acid chloride synthesis. By FTIR, elemental analysis, XRD, CPMA 13CNMR characterize its structure, as quantitative indicators of nitrogen mass fraction, the effects of reaction temperature, reaction time, materials ratio, the amount of pyridine Preparation of CMC-PA. IR, elemental analysis, CPMAS13CNMR show that CMC-PA has been generated: derived by single factor experiments synthesis conditions were as follows: m (Picric): m (acylated carboxymethyl cellulose) = 2:1, pyridine used in an amount of 50 ml The reaction temperature is 85 ° C, reaction time 4h. In simulated physiological conditions of the medium, the measured adsorption properties of CMC-PA creatinine, draw a curve and adsorption isotherms of adsorption kinetics. The results show that the CMC-PA creatinine adsorption equilibrium time of 10h, the maximum adsorption capacity for 1.75mg / g creatinine. The creatinine in CMC-PA on the adsorption equilibrium meet Freundich equation, instructions are primarily chemical adsorption, and absorption index (1 / n) is less than 1 indicated that the adsorption of the \In simulated physiological conditions of the medium by UV spectrophotometry (UV) measurement wavelength 358nm, pH value, hydrolysis time and place time on the CMC-PA stability; measurement wavelength to 303nm measured the CMC-PA in different adsorption time of the adsorption properties of vitamin B6. The results show that, 4 ~ 6 h at pH 1,2,8 a buffer solution, the rate of hydrolysis of the CMC-PA were 0.47% to 0.69%, 0.213% to 0.226%, 1.318% to 1.418%, room temperature next place after 2, 4, 6, 8 months, 37 ° C, the adsorption capacity of creatinine compared with CMC-PA, the new system not changed significantly compared to the other, CMC-PA in a different time under the conditions of vitamin B6 no significant adsorption. As raw materials, to the acidification of the sodium carboxymethyl cellulose sodium periodate as a selective oxidizing agent, the oxidized carboxymethyl cellulose was prepared under acidic conditions. 6 a carboxyl group of the carboxymethyl cellulose and then oxidized to an acylation, reaction with picric preparing composite targeted oral adsorbent-picric - oxidized carboxymethylcellulose ester. By XRD, FTIR, element analysis and chemical functional groups (alkali fusion method to measure aldehyde content) and other means of picric acid - oxidation of carboxymethyl cellulose ester structure was measured to characterize the results showed that the picric acid - oxidation carboxymethyl cellulose the ester has generated; under simulated physiological medium conditions, the determination of picric acid - oxidation carboxymethyl cellulose ester adsorption properties of urea and creatinine, urea and creatinine adsorption equilibrium time was 10h and 6h aldehyde content 75.23% saturated adsorption capacity of urea and creatinine were 16.08 mg / g and 2.10 mg / g. Urea adsorption isotherms on the oxidized CMC-PA meet Freundich equation described mainly for chemical adsorption and absorption index (1 / n) is less than 2, indicating that the adsorption of the \Thermodynamic functions calculated oxidation of CMC-PA on the same amount of urea adsorption enthalpy, free energy of adsorption and adsorption entropy. Oxidation of CMC-PA on urea adsorption chemical adsorption the spontaneous adsorption endothermic process: oxidation CMC-PA adsorption mechanism.
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