Quantitative Analysis of Cellulose in Tobacco by 13C CPMAS NMR

Abstract

A method utilizing 13C CPMAS NMR was developed for the quantitative determination of cellulose in tobacco. The method was employed to measure cellulose in hot water extracted laminae and stems from bright and burley tobacco. A reference spectrum of tobacco cellulose was subtracted from the spectrum of each sample to obtain a sub-spectrum of the noncellulose components. This background spectrum was subtracted in turn from the original spectrum to give an appropriately scaled sub-spectrum of the cellulose alone. A calibration curve was constructed from the integrals of the C-1 resonance of a set of standard cellulose samples. The integrals were measured relative to an intensity standard contained in a ceramic cell inside the MAS sample rotor. The weight percentage of cellulose in each tobacco residue was then determined by comparison of the integral of the cellulose C-1 resonance in its cellulose sub-spectrum to the calibration curve. Keywords: Tobacco; 13C CPMAS NMR; plants; cellulose