TY - JOUR
T1 - Standard addition flow method for potentiometric measurements at low concentration levels
T2 - application to the determination of fluoride in food samples
AU - Galvis-Sánchez, Andrea C.
AU - Santos, João Rodrigo
AU - Rangel, António O. S. S.
PY - 2015/2
Y1 - 2015/2
N2 - A standard addition method was implemented by using a flow manifold able to perform automatically multiple standard additions and in-line sample treatment. This analytical strategy was based on the in-line mixing of sample and standard addition solutions, using a merging zone approach. The flow system aimed to exploit the standard addition method to quantify the target analyte particularly in cases where the analyte concentration in the matrix is below the lower limit of linear response of the detector. The feasibility of the proposed flow configuration was assessed through the potentiometric determination of fluoride in sea salts of different origins and different types of coffee infusions. The limit of quantification of the proposed manifold was 5×10-6 mol L-1, 10-fold lower than the lower limit of linear response of the potentiometric detector used. A determination rate of 8 samples h-1 was achieved considering an experimental procedure based on three standard additions per sample. The main advantage of the proposed strategy is the simple approach to perform multiple standard additions, which can be implemented with other ion selective electrodes, especially in cases when the primary ion is below the lower limit of linear response of the detector.
AB - A standard addition method was implemented by using a flow manifold able to perform automatically multiple standard additions and in-line sample treatment. This analytical strategy was based on the in-line mixing of sample and standard addition solutions, using a merging zone approach. The flow system aimed to exploit the standard addition method to quantify the target analyte particularly in cases where the analyte concentration in the matrix is below the lower limit of linear response of the detector. The feasibility of the proposed flow configuration was assessed through the potentiometric determination of fluoride in sea salts of different origins and different types of coffee infusions. The limit of quantification of the proposed manifold was 5×10-6 mol L-1, 10-fold lower than the lower limit of linear response of the potentiometric detector used. A determination rate of 8 samples h-1 was achieved considering an experimental procedure based on three standard additions per sample. The main advantage of the proposed strategy is the simple approach to perform multiple standard additions, which can be implemented with other ion selective electrodes, especially in cases when the primary ion is below the lower limit of linear response of the detector.
KW - Coffee
KW - Flow system
KW - Fluoride ion selective electrode
KW - Sea salt
KW - Standard addition method
KW - Water
UR - http://www.scopus.com/inward/record.url?scp=84913597250&partnerID=8YFLogxK
U2 - 10.1016/j.talanta.2013.12.058
DO - 10.1016/j.talanta.2013.12.058
M3 - Article
C2 - 25435218
AN - SCOPUS:84913597250
SN - 0039-9140
VL - 133
SP - 1
EP - 6
JO - Talanta
JF - Talanta
ER -