摘要：

In this work, perfumery aldehydes which included aromatic aldehyde (vanillin and cinnamaldehyde) and aliphatic aldehyde (citral and citronellal) were successfully reacted with N-succinylchitosan to form Schiff base. The structure of the Schiff base was characterized by ATR-FTIR spectroscopy. The new absorption peaks at 1635 cm is due to C=N stretching vibrations of the imine bond. In aqueous media the imine-N-succinylchitosan form its nanospherecal shape. The results suggest that prepared nanoparticles were used as a novel material in delivery system. confirm the structure of the Schiff base (imine bond) Figure 1 shows the ATR-FTIR spectra of the chitosan (a), N-SCS (b) and that of the imine-N-SCS (c). All of spectra exhibit the absorption peaks at 1143, 1070 and 1027 cm, which can be assigned to C-O-C stretching and C-O stretching of glucosamine unit. In the ATR-FTIR spectrum of the Schiff base (Fig. 1c), new absorption peaks appear at 1635 cm corresponding to the C=N vibrations characteristic of imines. Moreover, the obtained Schiff base products were analyzed by AFM. The AFM image clearly shows undeformed spheres (Fig. 2). Back ground Polymeric nanoparticle containing fragrances is one of high interesting delivery. Recently, strategies those are required for controlling can be derived into two systems. One is the physical encapsulation whereas another is chemical derivation. In the former strategy, molecules are encapsulated by polymeric micro/nano capsule or matrix in order to control their diffusion. Furthermore the controlled releasing ability, the encapsulation strategy with using properly designed polymers enables protection of active molecules against degradation by light, air and moisture. Conversely, in the latter strategy, active molecules are derived into the corresponding protected forms using various chemical protection methods. Among various reactions for the chemical derivation strategy, reactions of amine with aldehydes to obtain the Schiff base or imine (C=N) have been popularly used. Chitosan has both reactive amino and hydroxyl groups that can be used to chemically alter its properties under mild reaction conditions. The presence of amino groups leads to the possibility of several chemical modifications, including the preparation of Schiff bases. Fig. 1. Representative ATR-FTIR spectra of (a) chitosan, (b) N-SCS and (c) imine-N-SCS Objective To synthesis a novel controlled release system for perfumery aldehydes Experiment Synthesis of imine-N-SCS. N-Succinylchitosan (N-SCS) was allowed to react with aldehydes which covered both aromatic aldehydes (vanillin and cinnamaldehyde) and aliphatic aldehyde (citral and citronellal). The procedure under ultrasound for 4 h involved dispersing the N-SCS in water and adding drop-wise the solution of aldehyde in ethanol. Results and Discussion On the Schiff base formation between N-SCS and aldehydes. ATR-FTIR spectroscopy was used to Fig. 2. Representative AFM image of N,N'Citralidene-succinylchitosan nanoparticle

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