چكيده به لاتين
Abstract
Polycyclic aromatic hydrocarbons (PAHs) are persisted organic pollutant which have two or
more fused benzene rings. They are widely distributed environmental contaminants that have
hazardous biological effects, toxicity, and carcinogenicity. They originated from incomplete
pyrolysis of organic compound. Some techniques such as adsorption, photolysis and
volatilization are used in the determination of PAHs, which between these methods,
adsorption is the best method. Mechanical stir bar sorptive extraction is a new format of stir
bar sorptive extraction. In this method, sorbent was coated on the mechanical stir bar and
could overcome on some defects of stir bar sorptive extraction. In the present work,
Polyacrylonitrile and polydimethylsiloxane nanofibers were coated on a mechanical stir bar
by electrospinning method and used in mechanical stir bar sorptive extraction of PAHs in non
alcoholic beer sample coupled with gas chromatography with flame ionization detector. To
reach the optimum extraction efficiency, affecting parameters, including sorption and
desorption time, sample volume and stirring rate were investigated by a central composite
design. Optimum conditions were 60 minutes, 10 minutes, 16 millilitre and 1300 rpm, for
mentioned parameters, respectively. Under optimum conditions the calibration curves in the
range of 5-1000 ng/mL for naphthalene ,acenaphthene, acenaphthylene, anthracene and
phenanthrene. The limits of detection (LOD) and limits of qualification (LOQ) were 0.009-
0.5 ng/mL and 0.03-1.5 ng/mL, respectively. The relative standard deviation (RSDs) for five
analytes at a concentration in 10 ng/mL were less than 11%. Recovery and enrichment factor
were in 94-98 and 117-126, respectively.
Keywords: Mechanical stir bar sorptive extraction; Polycyclic aromatic hydrocarbons; Gas
chromatography; Electrospinning; Nanosorbent; Polydimethylsiloxane; Polyacrylonitrile
