title: Continuous in vivo monitoring of blood diffusible calcium using on-line microdialysis sampling coupled with flame atomic absorption spectrometry.
abstract: A direct, rapid and continuous in vivo monitoring of diffusible calcium in the blood of living rabbits has been developed using microdialysis sampling coupled on-line with flame atomic absorption spectrometry. Microdialysates perfused through implanted microdialysis probes were collected with a sample loop on an injection valve and directly introduced into the flame atomizer by a carrier solution. An ultrapure saline solution (0.9% NaCI, pH 7.2) was used as the perfusion solution at a flow rate of 20 microI min(-1) via the microdialysis probe. A 0.1% La solution in 0.5% HNO3 solution was employed as the carrier solution at a nebulizer uptake flow rate of 2.5 ml min(-1). The interval for each determination was 2.5 min (2 min of sampling time, 20 s of read time and 10 s of washing time). The performance characteristics of the on-line microdialysis-FAAS system were validated as follows: linearity range, 0 - 100 mg l(-1); detection limit (3a, n = 7), 3.66 mg l(-1); precision (RSD, n = 50), 6.2%. For the evaluation of analytical accuracy, the proposed on-line method was compared with the in vivo no net flux method. The use of an on-line microdialysis-FAAS system permitted the in situ, dynamic and continuous in vivo monitoring of diffusible calcium in the blood of the living rabbits after CaCl2 administration with a temporal resolution of 2.5 min.
authors.affiliation: Department of Medical Technology, Fooyin University, Kaohsiung, Taiwan.
authors.forename: Wei-Chang
authors.initials: WC
authors.lastname: Tseng
authors.forename: Yuh-Chang
authors.initials: YC
authors.lastname: Sun
authors.forename: Cheng-Fa
authors.initials: CF
authors.lastname: Lee
authors.forename: Mo-Hsiung
authors.initials: MH
authors.lastname: Yang
authors.forename: Yeou-Lih
authors.initials: YL
authors.lastname: Huang
mesh_terms: D000818:Animals; D002118:Calcium / Q000097:blood* / Q000378:metabolism; D004058:Diffusion; D008297:Male; D017551:Microdialysis / Q000379:methods*; D011817:Rabbits; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013054:Spectrophotometry, Atomic / Q000379:methods*
chemical_list: D002118:Calcium