کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1170190 960669 2008 7 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Steady-state diffusion regime in solid-phase microextraction kinetics
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی آنالیزی یا شیمی تجزیه
پیش نمایش صفحه اول مقاله
Steady-state diffusion regime in solid-phase microextraction kinetics
چکیده انگلیسی
The temporal evolution of diffusion-controlled analyte accumulation in solid-phase microextraction (SPME) is critically discussed in terms of the various aspects of steady-state diffusion in the two phases under conditions of fast exchange of the analyte at the solid phase film/water interface. For partition coefficients (Ksw) much larger than unity and a sufficiently thin polymer film, the concentration gradient of the analyte in the polymer phase is largely insignificant. The growth of the accumulated amount of analyte is then adequately described by the well-known exponential expression for steady-state diffusion under non-depletive conditions, provided the initial transient stage is properly taken into account. In case of fiber-type solid phases, the cylindrical nature of the diffusion complicates the nature of the transient stage as well as the magnitude of the steady-state flux.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Analytica Chimica Acta - Volume 609, Issue 1, 18 February 2008, Pages 113-119
نویسندگان
, , ,