Parameter optimization for determining pH values of total particulate matter of mainstream cigarette smoke with response surface analysis
In order to accurately determine the pH values of total particulate matter (TPM) in mainstream cigarette smoke, the absolute value of relative mean error was used as an assessment index, 4 factors, including extract solvent volume, oscillation extracting duration, oscillation extracting frequency and concentration of isopropyl alcohol extraction solution, at 3 levels were tested and analyzed by response surface optimization analysis according to Box-Behnken center-united experimental design principle, and the interactions among the 4 factors were also discussed. The results showed that: 1) The optimum extraction parameters were extraction solvent 70 mL, extraction time 30 minutes, oscillation frequency 180 r/min and extraction solution 50% isopropyl alcohol-water solution. 2) The relative standard deviations of the method were from 0.21% to 0.39%.