Cigarettes were conditioned 24 hr at 75°F and 60% relative humidity prior to being selected and smoked in a random order. Cigarettes were smoked in a Cambridge filter holder on an automatic smoking machine to a pre-determined butt length. TPM wet collection was on a CM113A filter disk and was determined as the net weight gain in the Cambridge filter holder after smoking. The filter pads were extracted with dioxane-isopropanol solution and were analyzed for moisture by gas chromatography. The pads and solvent extracts were steam distilled and the distillate was analyzed spectrophotometrically for nicotine. TPM dry was calculated as TPM wet minus nicotine and water. The coefficient of variation in this method is less than 5% with a 95% confidence level.

A high performance countercurrent chromatography (HPCCC) 1 process was developed as a more efficient and sustainable alternative to reverse phase high performance liquid chromatography (RP-HPLC) for the pilot scale purification of the naturally occurring fermentation-derived insecticides, spinosyn A and spinosyn D, the major components of 2 spinosad insecticide. While on pilot scale HPCCC and RP-HPLC both gave >99% purities and comparable combined recoveries of 77% and 83%, respectively, HPCCC was more efficient and sustainable by producing a 60% higher productivity, 11 times higher solute loading, 96% savings in stationary phase costs, and 42% reduction in solvent usage. The increase in productivity and reduction in solvent usage further reduced waste recycle and disposal costs, thus presenting significantly less environmental impact compared to RP-HPLC separations. Use of mixing on demand for solvent system at a preparative scale allowed a complete automation with minimized solvent consumption.

Two methods for determination of nicotine in cigarette smoke have been compared : distillation of a complete sample vs. distillation of an aliquot. For the evaluation of these methods, monitor cigarettes or cigarettes from cartons with the same packing codes purchased from a local store were used for each test set. The cigarettes were conditioned, selected, and smoked according to the official method published by the Federal Trade Commission. Because both isopropanol and dioxane are used as solvents, tests were conducted using both solvents; it was found that there was no difference in the results. Cigarettes for both methods were smoked at the same time and those from alternate ports were assayed for nicotine by the aliquot method. From the results obtained, it appears that nicotine is completely recovered when the entire pad, the quarter pad, and the extraction solution are distilled together. If an aliquot of one phase is to be used, it must be determined that the soughtafter substance is homogeneously distributed throughout all phases.

1.AbstractBacteriophages (phages) are viruses that target bacteria, with the ability to lyse and kill host bacterial cells. Due to this, they have been of some interest as a therapeutic since their discovery in the early 1900s, but with the recent increase in antibiotic resistance, phages have seen a resurgence in attention. Current methods of isolation and purification of phages can be long and tedious, with caesium chloride concentration gradients the gold standard for purifying a phage fraction. Isolation of novel phages requires centrifugation and ultrafiltration of mixed samples, such as water sources, effluent or faecal samples etc, to prepare phage filtrates for further testing. We propose countercurrent chromatography as a novel and alternative approach to use when studying phages, as a scalable and high-yield method for obtaining phage fractions. However, the full extent of the usefulness and resolution of separation with this technique has not been researched; it requires optimisation and ample testing before this can be revealed. Here we present an initial study to determine survivability of two phages, T4 and ϕX174, using only water as a mobile phase in a Spectrum Series 20 HPCCC. Both phages were found to remain active once eluted from the column. Phages do not fully elute from the column and sodium hydroxide is necessary to flush the column between runs to deactivate remaining phages.

Bacteriophages (phages) are viruses that target bacteria, with the ability to lyse and kill host bacterial cells. Due to this, they have been of some interest as a therapeutic since their discovery in the early 1900s, but with the recent increase in antibiotic resistance, phages have seen a resurgence in attention. Current methods of isolation and purification of phages can be long and tedious, with caesium chloride concentration gradients the gold standard for purifying a phage fraction. Isolation of novel phages requires centrifugation and ultrafiltration of mixed samples, such as water sources, effluent or faecal samples etc, to prepare phage filtrates for further testing. We propose countercurrent chromatography as a novel and alternative approach to use when studying phages, as a scalable and high-yield method for obtaining phage fractions. However, the full extent of the usefulness and resolution of separation with this technique has not been researched; it requires optimization and ample testing before this can be revealed. Here we present an initial study to determine survivability of two phages, T4 and ϕX174, using only water as a mobile phase in a Spectrum Series 20 HPCCC. Both phages were found to remain active once eluted from the column. Phages do not fully elute from the column and sodium hydroxide is necessary to flush the column between runs to deactivate remaining phages.