通过固态13C CP/MAS NMR技术,成功地建立了一种新方法用于烟草果胶的定量分析研究.首先,将二甲基硅橡胶设计成5.5 mm外径的硅胶管用作强度参考,再装填到5.5 mm内径的二氧化锆转子内以制成NMR样品管.然后,对样品管中的果胶样品进行检测以获得相应的13 C CP/MAS NMR光谱,再利用波谱去卷积技术分别对171 ppm处的C-6峰进行处理,以此消除重叠峰的干扰.最后,用指定的C-6峰与强度参考峰的面积比为纵坐标,聚半乳糖醛酸(PGA)标准样品的质量为横坐标,以此来建立工作曲线.获得工作曲线方程为I=0.0082m-0.2470,r2=0.9981,检出限和定量限分别为1.81 mg·g-1、6.04 mg·g-1.方法的加标回收率在94.33％ ～102.77％范围内,平均回收率为98.11％,RSD(n=5)小于2.32％.该方法用于测定6种不同烟草样品中的果胶含量,结果发现:与标准方法测量的结果相比,其相对误差在-4.94％ ～3.84％之间.研究表明,通过固态13 C CP/MAS NMR光谱和硅橡胶管建立的新方法准确、快速、简单,适用于烟草及其制品中果胶含量的定量分析.“,”A quantitative analysis method was developed for determination of pectin content in tobacco samples by solid state 13 C CP/MAS NMR. A 5. 5 mm outer diameter of dimethyl silicone rubber tubing was designed and utilized as a reference of intensity, which was packed into a 5. 5 mm inner diameter zirconia NMR rotor to construct an NMR sample tubing. The powder samples filled into the sample tubing were detected to obtain 13 C CP/MAS NMR spectra. The peak of C-6 at 171 ppm was processed with spectral deconvolution to eliminate interference from overlapping peaks. The calibration curve was established with the area ratios of assigned C-6 peak to intensity reference peak and the mass of the polygalacturonic acid ( PGA ) . This method was used to determine the pectin content in six different tobacco samples. Relative errors were between -4. 94％ and 3. 84％ compared with the results measured by the standard method. The recovery of PGA from spiked tobacco samples was ranged from 94. 33％ to 102. 77％, the RSD (n=5) was less than 2. 32％. It demonstrates that the 13C CP/MAS NMR method with a novel intensity reference possesses the properties of speediness, accuracy and simplicity, which is suitable for the quantitative analysis of pectin content in tobacco.