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METHODSA 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.

RESULTSThe 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.

CONCLUSIONStarch 3,5-dinitrobenzoate showed a better adsorption property for creatinine, and it is worthy to be studied more deeply.

Adsorption ; Creatinine ; chemistry ; Magnetic Resonance Spectroscopy ; Nitrobenzoates ; chemistry ; Spectroscopy, Fourier Transform Infrared ; Starch ; analogs & derivatives ; chemical synthesis ; chemistry

9.Efficacy of different target concentrations of sufentanil TCI used to supplement topical anesthesia for fiber-optic bronchoscopy-assisted awake nasotracheal intubation in patients with obstructive sleep apnea syndrome

Xue XU ; Qiuyue DONG ; Xiang QI ; Wei LI ; Zhi LIANG ; Luchao GAO

Chinese Journal of Anesthesiology 2013;33(9):1089-1092

Objective To compare the efficacy of different target concentrations of sufentanil target-controlled infusion used to supplement topical anesthesia for fiber-optic bronchoscopy (FOB)-assisted awake nasotracheal intubation in patients with obstructive sleep apnea syndrome (OSAS).Methods Forty-five ASA physical status Ⅱ or Ⅲ patients with OSAS,aged 28-60 yr,with body mass index of 30-40 kg/m2,scheduled for elective surgery,were randomly assigned into 3 groups (n =15 each):control group (group C) and sufentanil with the target plasma concentration of 0.4 ng/ml (group S1) and 0.6 ng/ml groups (group S2).Naso-pharyngeal and laryngeal mucous membrane was sprayed with 2％ lidocaine mixed with 1％ ephedrine for topical anesthesia in both groups.In addition 1％ tetracaine 3 ml was injected into trachea through cricothyroid membrane.FOB-assisted awake nasotracheal intubation was performed after the target concentration was achieved.The degree of airway obstruction was scored during intubation.The highest values of MAP and HR,rate-pressure product ＞ 12 000,decreased respiratory rate and hyoxemia were recorded during the period between induction of anesthesia and 3 min after intubation was completed.The changes in MAP and HR as percent of baseline values were calculated.Before topical anesthesia (T0),when target concentrations were reached (T1),and at 1 and 3 min after intubation (T2,3),blood samples were taken to determine the plasma concentrations of epinephrine (E),norepinephrine (NE) and cortisol.Results Compared with group C,the airway obstruction score was significantly decreased in group S1,the incidence of changes in MAP and HR ＞ 30％ of baseline values and rate-pressure product ＞ 12 000 was decreased,the plasma concentrations of E,NE and cortisol were decreased in S1 and S2 groups,and the incidence of the respiratory rate was decreased and hypoxemia was increased in group S2 (P ＜ 0.05).Compared with group S1,the airway obstruction score were significantly decreased,and the incidence of respiratory rate was decreased and hypoxemia was increased in group S2 (P ＜ 0.05).Compared with the baseline value at T0,the plasma concentrations of E,NE and cortisol were significantly increased at T2,3 in group C,while decreased at T1 in S1 and S2 groups (P ＜ 0.05).Conclusion Compared with pure topical anesthesia,sufentanil with the target plasma concentration of 0.4 ng/ml does not induce respiratory depression,maintains hemodynamics stable,attenuates the stress responses and provides better intubation conditions when used to supplement topical anesthesia for FOB-assisted awake nasotracheal intubation in patients with OSAS.