title: Evaluation of the availability of bound analyte for passive sampling in the presence of mobile binding matrix.
abstract: Elucidating the availability of the bound analytes for the mass transfer through the diffusion boundary layers (DBLs) adjacent to passive samplers is important for understanding the passive sampling kinetics in complex samples, in which the lability factor of the bound analyte in the DBL is an important parameter. In this study, the mathematical expression of lability factor was deduced by assuming a pseudo-steady state during passive sampling, and the equation indicated that the lability factor was equal to the ratio of normalized concentration gradients between the bound and free analytes. Through the introduction of the mathematical expression of lability factor, the modified effective average diffusion coefficient was proven to be more suitable for describing the passive sampling kinetics in the presence of mobile binding matrixes. Thereafter, the lability factors of the bound polycyclic aromatic hydrocarbons (PAHs) with sodium dodecylsulphate (SDS) micelles as the binding matrixes were figured out according to the improved theory. The lability factors were observed to decrease with larger binding ratios and smaller micelle sizes, and were successfully used to predict the mass transfer efficiencies of PAHs through DBLs. This study would promote the understanding of the availability of bound analytes for passive sampling based on the theoretical improvements and experimental assessments.
authors.affiliation: MOE Key Laboratory of Aquatic Product Safety/KLGHEI of Environment and Energy Chemistry, School of Chemistry and Chemical Engineering, Sun Yat-sen University, Guangzhou 510275, China.
authors.forename: Jianqiao
authors.initials: J
authors.lastname: Xu
authors.affiliation: MOE Key Laboratory of Aquatic Product Safety/KLGHEI of Environment and Energy Chemistry, School of Chemistry and Chemical Engineering, Sun Yat-sen University, Guangzhou 510275, China.
authors.forename: Shuyao
authors.initials: S
authors.lastname: Huang
authors.affiliation: School of Environment, Jinan University, Guangzhou 510632, China.
authors.forename: Ruifen
authors.initials: R
authors.lastname: Jiang
authors.affiliation: Department of Biological Applied Engineering, Shenzhen Polytechnic, Shenzhen 518055, China.
authors.forename: Shufen
authors.initials: S
authors.lastname: Cui
authors.affiliation: MOE Key Laboratory of Aquatic Product Safety/KLGHEI of Environment and Energy Chemistry, School of Chemistry and Chemical Engineering, Sun Yat-sen University, Guangzhou 510275, China.
authors.forename: Tiangang
authors.initials: T
authors.lastname: Luan
authors.affiliation: MOE Key Laboratory of Aquatic Product Safety/KLGHEI of Environment and Energy Chemistry, School of Chemistry and Chemical Engineering, Sun Yat-sen University, Guangzhou 510275, China.
authors.forename: Guosheng
authors.initials: G
authors.lastname: Chen
authors.affiliation: MOE Key Laboratory of Aquatic Product Safety/KLGHEI of Environment and Energy Chemistry, School of Chemistry and Chemical Engineering, Sun Yat-sen University, Guangzhou 510275, China.
authors.forename: Junlang
authors.initials: J
authors.lastname: Qiu
authors.affiliation: School of Mathematics and Computational Science, Sun Yat-sen University, Guangzhou 510275, China.
authors.forename: Chenyang
authors.initials: C
authors.lastname: Cao
authors.affiliation: MOE Key Laboratory of Aquatic Product Safety/KLGHEI of Environment and Energy Chemistry, School of Chemistry and Chemical Engineering, Sun Yat-sen University, Guangzhou 510275, China. Electronic address: ceszhuf@mail.sysu.edu.cn.
authors.forename: Fang
authors.initials: F
authors.lastname: Zhu
authors.affiliation: MOE Key Laboratory of Aquatic Product Safety/KLGHEI of Environment and Energy Chemistry, School of Chemistry and Chemical Engineering, Sun Yat-sen University, Guangzhou 510275, China. Electronic address: cesoygf@mail.sysu.edu.cn.
authors.forename: Gangfeng
authors.initials: G
authors.lastname: Ouyang
keywords: Diffusion boundary layer; Lability factor; Mobile binding matrix; Passive sampling kinetics; Polycyclic aromatic hydrocarbons; Sodium dodecylsulphate