Suresh Ralapati, batf/National Laboratory Center

Sample Preparation. Nicotine in ATF regulated tobacco products is extracted using the method developed by Jablonski as described by Gottscho et al. (82). A sample of tobacco product (1.0 g) is treated with 7.5 mL of 1N HCl and left to stand 10 min at room temperature. The sample is allowed to wet completely. The sample is then extracted with vigorous shaking on a shaker in 25 mL of extracting solution (prepared by mixing 600 mL of chloroform with 400 mL hexane containing 0.6 g octadecane as internal standard) and 5.0 mL of 36% NaOH for 20 min at room temperature. The extract is then treated with 3.0 g of diatomaceous earth, shaken to wet it completely, and filtered through a sintered glass funnel. A standard nicotine solution is prepared by weighing 0.06 g of nicotine into a 100 mL volumetric flask and made to volume with the extracting solution.
End Determination. 1.0 uL aliquots of standard nicotine and filtered tobacco extracts are injected in tandem and analyzed by GC. The GC system typically used consists of a Hewlett-Packard (HP) GC Series 5890 fitted with a capillary column (0.53 mm x 16 m coated with Supelcowax 10) and equipped with both a flame ionization detector (FID) and a HP Integrator Series 3393A integrator. Helium is used as the carrier gas at a flow rate of 11.6 mL/min, a head pressure of 5 KPa and a split ratio of 3:1. Column temperature is maintained at 190^oC and injection temperature at 230^oC. Samples are injected automatically using the HP Autoinjector Series 7736A. Figure 20 shows the gas chromatographic analysis of nicotine in an ATF regulated tobacco product.
Nicotine Reporting Requirements. Current ATF regulatory classifications are based on qualitative information. As such, declaration of the presence or absence of nicotine in a particular sample is the only reporting requirement with this method. However, quantitative determination of nicotine in tobacco is also possible with the method. If quantitative results are reported, the percent total alkaloids, expressed as nicotine, are reported for samples on a dry weight basis. Nicotine concentration in the starting tobacco is calculated based on an internal standard calculation.


Current Pratices (Capillary Electrophoresis). Capillary electrophoresis (CE) is rapidly gaining importance as an analytical technique, capturing the interest of analytical scientists in several areas (26,89,90). The unique and powerful capabilities of CE include rapid analysis times, low sample consumption, high efficiency, high resolution and selectivity, thus making CE a powerful analytical tool that is complementary to other analytical techniques such as HPLC. Application of capillary electrophoresis to determine nicotine in ATF regulated tobacco products was first reported in 1997 (26). The current analytical technique for the analysis of nicotine in ATF regulated tobacco products is capillary electrophoresis (CE).


Method Scope. Nicotine is obtained by aqueous extraction of tobacco products. The aqueous extract is analyzed by CE using a pH 2.5 sodium phosphate buffer followed by UV detection at 260 nm.