Analysis of smoke PAHs from selected Taiwanese cigarettes by using molecular imprinting polymers

Abstract

Polycyclic aromatic hydrocarbons (PAHs) and their derivatives are common trace pollutants produced during incomplete combustion of organic substances, such as tobacco. After sampling cigarette smoke, PAH collators must undergo pretreatment processes such as extraction, cleanup and concentration before instrument analysis. This study combines molecular imprinted polymers (MIPs) and solid-phase extraction (SPE) to create a novel sample pretreatment technique. Experimental results demonstrate that MIPs have good selectivity for benz[a]pyrene (BaP) from a mixture of 16 PAH solvents. The MIPs were applied to a sample taken from mainstream smoke from a cigarette. Based on functional monomers and crosslinkers, this study investigated two groups of MIPs. After the template was removed, various tests, including capacity, selectivity, recovery, scanning electron microscope (SEM) observations and real environmental sample tests, were conducted. Experimental results show that MIP-1 is the best MIP, with a capacity of 20.78 ± 1.7 (μ g/g), BaP selectivity and recovery exceeding 93%. In environmental sample tests, i.e., mainstream smoke from S and M brand cigarettes, 80% of BaP was absorbed by the MIP compared with absorbed by the filters. All experimental results suggest that MIPs effectively adsorbed BaP among 16 different PAHs, reduced background interference and increased signal resolution compared with traditional extraction techniques. Additionally, using MIPs for sample pretreatment is less time-consuming than traditional sample pretreatments and also reduces the amount of organic solvent used. Using molecular imprinted polymers solid extraction (MISPE) may separate target analytes from a complex sample more effectively than traditional Soxhlet extraction. Future toxicity tests should contribute to the understanding of toxic compounds emitted from specific pollution sources.

Keywords:

• Molecular imprinted polymer
• solid-phase extraction
• cigarette mainstream smoke
• toxicity separation

Acknowledgments

The authors would like to thank the National Science Council of the Republic of China, Taiwan, for financially supporting this research under Contract No. NSC 95-2221-E-006-175.

Notes

∗Mainstream smoke was collected using glass fiber filters and extracted using Soxhlet methods.

^# For NIP-1, NIP-2, MIP-1 and MIP-2 the mainstream smoke were collected using cartridges. The cartridges were washed with acetonitrile mixed with de-ionized water, and eluted with a mixed solvent containing dichloromethane and n-hexane.

∗Q_NIP represents the maximum non-imprinted polymers adsorption capacity; Q_MIP represents the maximum imprinted polymers adsorption capacity.

^# Q_MIP/Q_NIP represents the imprinted factor.

∗S represent S brand, M represent M brand.