13c Cp Mas Nmr Pectin Chitosan

Cp mas 13 c nmr heux et al.

13c cp mas nmr pectin chitosan. The structures of acetylated and deacetylated monomers of chitosan are presented in fig. The mas rate was in the 4 5 khz range. 94 biotechnology of biopolymers 3 2 potentiometric titration chitosan ca. In this study the relaxation delay and contact time leading to quantitative chitin and deacetylated chitin 13 c cp mas nmr spectra have been determined.

The assignment of chitosan peaks have already been reported in the literature. Chitin and chitosan were analyzed by x ray 13c cp mas nmr 13c ft chitin samples in a alpha form structure were isolated from beetle larva cuticle and silkworm bombyx mori pupa exuvia by treatment with 1 n hcl and 1 n naoh. 1h and 13c nmr spectra of chitosan allow a good characterization of the starting materials. Cp mas 13 c nmr and cp mas 15 n nmr are appropriate methods for insoluble chitin chitosan samples even the samples are associated with impurities and humidity ottøy et al 1996.

5 4 solid state 13 c nuclear magnetic resonance. 2 presents the 400 mhz 1 h nmr spectrum of chitosan pcch00005 dda 87 at 70 c. The conditions of acid extraction of tobacco samples and. A double air bearing probe and a zirconium oxide rotor were used.

The cp mas 13 c nmr spectra were recorded at 292 1 k on a bruker amx 300 instrument operating at 7 05 t. The degree of acetylation of chitin and deacetylated chitin samples determined from the 13 c cp mas nmr spectra acquired with the optimised relaxation delay 5 s and contact time 1 ms is 0 68 and 0 16 respectively. Chitosan was prepared by treating them in 40 naoh containing nabh 4. Dd obtained by solid state 13 c nmr for low acetyl chitosan was not coincident with the.

Acquisition was performed with a standard cp pulse sequence using a 3 5 μs proton 90 pulse a 800 μs contact pulse and a 2 5 s. Nishioka sulfated derivatives of chitosan and their characterization with respect to biological activity chitin in nature and technology 10 1007 978 1 4613 2167 5 461 468 1986. Cp mas 13 c nmr spectra of sclerotized insect cuticle and of chitin. The graph with the variation of ph versus the.

The solvent hod proton resonates at 4 67 ppm. The polysaccharidic component of these hydrogels is chitosan while the novel cross linking agent is diethyl squarate des. 100 mg is dissolved in a known volume of aqueous hcl 0 010 mol l 1 and the solution is then ti trated with 0 1 mol l 1 naoh while the ph of the solution is measured at constant ionic strength 0 1 mol l 1 nacl. A new method utilizing 13c cp mas nmr spectra was developed for the simultaneous quantitative and structure analysis of pectin in tobacco.

Table 1 shows the chemical shifts of chitosan protons in d 2 o dcl at 70 c.