[Comparison and optimization of total ionic strength adjustment buffer during detecting fluoride in trace serum
Wei Sheng Yan Jiu = Journal of Hygiene Research
|June 16, 2016
Summary
The optimal total ionic strength regulating buffer (TISAB) for fluoride determination in rat serum is TISAB III, while TISAB IV is best for calf serum. The health industry standard method is unsuitable for rat serum fluoride analysis.
Area of Science:
- Analytical Chemistry
- Electrochemistry
Background:
- Accurate determination of trace fluoride in biological samples is crucial for health assessments.
- Fluoride ion-selective electrodes (FISE) are commonly used for fluoride quantification.
- The choice of buffer systems, such as total ionic strength regulating buffer (TISAB), significantly impacts measurement accuracy.
Purpose of the Study:
- To evaluate the influence of four different TISAB types on fluoride determination in rat and calf serum using FISE.
- To establish optimal standard curves and determine the best TISAB for trace fluoride analysis.
- To identify the ideal volume ratio between TISAB and serum samples for accurate fluoride measurement.
Main Methods:
- Established standard curve equations for four TISAB types to assess their influence.
- Diluted rat and calf serum samples 1:1 with each TISAB.
- Analyzed fluoride recovery rates after standard sodium fluoride addition to determine TISAB effectiveness.
- Optimized serum to TISAB volume ratios based on recovery rates.
Main Results:
- TISAB III demonstrated the best standard curve fit (R² = 0.9926) and recovery rates (90-105%) in rat serum.
- TISAB IV, the health industry standard, showed superior recovery rates (90-110%) in calf serum.
- Optimal volume ratios were identified for each TISAB, with TISAB III at 1:1 being optimal for rat serum; calf serum recovery was less sensitive to volume ratio changes.
Conclusions:
- The health industry standard TISAB (TISAB IV) is suitable for trace fluoride determination in calf serum but not in rat serum.
- TISAB III is recommended for accurate fluoride quantification in rat serum.
- Optimizing TISAB type and volume ratio is critical for reliable trace fluoride analysis in different biological matrices.
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