Abstract: To effectively evaluate the content of inorganic anions in cigar tobacco leaves and their correlation with position, grade, and origin, a method based on ultrasonic extraction and ion chromatography was developed for the simultaneous determination of five inorganic anions (F^-、Cl^-、SO₄^2-、NO₃^-、PO₄^3-). The pretreatment conditions such as extraction method and extraction temperature, as well as the ion chromatography analytical conditions, were systematically optimized, and quantitative determination of target ions in 40 cigar tobacco leaf samples was successfully achieved, and the correlations between the contents of five inorganic anions and position, grade, and origin were investigated. The results showed that the optimal extraction efficiency was achieved when tobacco leaf samples were extracted by ultrasonic extraction at 40 °C for 40 min, and the five inorganic anions were completely separated within 10 min. The method detection limit (LOD) ranged from 0.02 to 0.07 mg/L, and the quantification limit (LOQ) ranged from 0.08 to 0.24 mg/L. The intra-day precision was ≤2.25%, the inter-day precision was ≤3.94%, and the spike recovery rates ranged from 90.0% to 106.2%. The contents of F^- and PO₄^3- in cigar tobacco leaves were relatively low, while the Cl^- content was relatively high in some samples. Significant differences in inorganic anion content were observed among cigar tobacco leaves from different production areas, and the content increased with the improvement of tobacco leaf grade. The inorganic anion content increased sequentially from upper, middle, to lower position tobacco leaves, indicating a certain correlation between inorganic anion content and the position, grade, and origin of cigar tobacco leaves.

Key words: ultrasonic extraction-ion chromatography, inorganic anions, cigar, tobacco leaf