TY  - JOUR
A1  - Alker, Wiebke
A1  - Schwerdtle, Tanja
A1  - Schomburg, Lutz
A1  - Haase, Hajo
T1  - A Zinpyr-1-based Fluorimetric Microassay for Free Zinc in Human Serum
JF  - International journal of molecular sciences
N2  - Zinc is an essential trace element, making it crucial to have a reliable biomarker for evaluating an individual’s zinc status. The total serum zinc concentration, which is presently the most commonly used biomarker, is not ideal for this purpose, but a superior alternative is still missing. The free zinc concentration, which describes the fraction of zinc that is only loosely bound and easily exchangeable, has been proposed for this purpose, as it reflects the highly bioavailable part of serum zinc. This report presents a fluorescence-based method for determining the free zinc concentration in human serum samples, using the fluorescent probe Zinpyr-1. The assay has been applied on 154 commercially obtained human serum samples. Measured free zinc concentrations ranged from 0.09 to 0.42 nM with a mean of 0.22 ± 0.05 nM. It did not correlate with age or the total serum concentrations of zinc, manganese, iron or selenium. A negative correlation between the concentration of free zinc and total copper has been seen for sera from females. In addition, the free zinc concentration in sera from females (0.21 ± 0.05 nM) was significantly lower than in males (0.23 ± 0.06 nM). The assay uses a sample volume of less than 10 µL, is rapid and cost-effective and allows us to address questions regarding factors influencing the free serum zinc concentration, its connection with the body’s zinc status, and its suitability as a future biomarker for an individual’s zinc status.
KW  - zinc
KW  - free zinc
KW  - serum
KW  - biomarker
KW  - fluorescent probe
KW  - Zinypr-1
Y1  - 2019
U6  - https://doi.org/10.3390/ijms20164006
SN  - 1661-6596
SN  - 1422-0067
VL  - 20
IS  - 16
PB  - MDPI
CY  - Basel
ER  -