title: [Synthesis of a novel starch derivative and its adsorption property for creatinine].
abstract: OBJECTIVE
  To prepare a novel creatinine adsorbent with anti-renal failure activity.
  
  
  METHODS
  A novel starch ester was prepared under heterogeneous condition by the reaction of starch (ST) and 3, 5-dinitrobenzoyl chloride (DNBZ-Cl). The products were characterized by means of elemental analysis, FTIR, 13CNMR and UV-Vis spectra. The adsorption properties of DNBZ-ST were examined.
  
  
  RESULTS
  The adsorption equilibrium is reached after 4 h, the adsorption capacity increases with the degree of substitution (DS) of adsorbent and creatinine concentration. When creatinine concentration is higher than 300 mg.L-1, concentration showed no apparent effect on adsorption capacity. As the adsorption temperature varied from 19 degrees C to 49 degrees C, adsorption capacity first decreases and then increases, and is lowest at 37 degrees C. The adsorption capacity first increases and then decreases as the pH value increase from 4 to 11 and is highest at pH 8. The highest adsorption capacity reached 25 mg.g-1 at 37 degrees C pH 7 and the creatinine concentration is 100 mg.L-1.
  
  
  CONCLUSIONS
  Starch 3,5-dinitrobenzoate showed a better adsorption property for creatinine, and it is worthy to be studied more deeply.
authors.affiliation: Chemistry Department, School of Science, Tianjin University, Tianjin 300072, China.
authors.forename: Jiu-gao
authors.initials: JG
authors.lastname: Yu
authors.forename: Dong-zhi
authors.initials: DZ
authors.lastname: Yang
mesh_terms: D000327:Adsorption; D003404:Creatinine / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D009579:Nitrobenzoates / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared; D013213:Starch / Q000031:analogs & derivatives / Q000138:chemical synthesis* / Q000737:chemistry
chemical_list: D009579:Nitrobenzoates; C013964:3,5-dinitrobenzoyl chloride; D013213:Starch; D003404:Creatinine