RESUMO
Objective]To establish a new method for grafting ratio(GR) analysis of deoxycholic acid grafted chitosan(CS-DCA). [Methods]In this study, linear potentiometric titration(LPT) and 2,4,6-trinitrobenzenesulfonicacid(TNBS) were introduced to measure the GR of CS-DCA, using the 1H-nuclear magnetic resonance(1H-NMR) as reference, the results obtained by the two methods were analyzed to find a method to substitute H-NMR. [Results]There was no significant difference of the data determined by 1H-NMR and LPT(P>0.05), however, it didn't apply to 1H-NMR and TNBS(P<0.05), the results indicated that LPT had equivalent accuracy of 1H-NMR. Using 1H-NMR method as the standard reference, the relative error was no more than 3.8% for the method of LPT, and the maximum relative error for the method of TNBS was up to 12.8%, it meant that LPT had higher precision. [Conclusion]LPT is an economical, rapid and accurate method for the GR analysis of CS-DCA.