Validation of a patented method to determine the antioxidant capacity of human saliva based on the reduction of iron: the SAT test.

ABSTRACT

BACKGROUND: The defense against damaging attack at mouth level caused by reactive species, in particular reactive oxygen species (ROS), is guaranteed by saliva, the main constituent of the antioxidant barrier. The aim of the performed tests was to establish the precision, linearity, and accuracy of the new patented test, SAT, on saliva samples taken from healthy volunteers. The analysis also provided useful information on storage conditions of the sample at low temperatures and on the normality range and defined the influences of interferences (in particular phosphates) in the determination. METHODS: Sixty apparently healthy volunteers were selected to verify the antioxidant capacity of the oral cavity using the new patented SAT method. RESULTS: SAT performed on 70 saliva samples demonstrated that the test was precise, linear (R = 0.9994), accurate, and reproducible (CV 4.39%). The SAT values in the saliva samples analyzed had a normal distribution with a control range for healthy subjects of 947-1459 micromol/L. The fundamental presence of a particular salt in the SAT solutions allowed avoidance of phosphate interference and eliminated false positives. CONCLUSIONS: SAT can be considered an important predictive test not only for periodontal disease, caries, gingivitis, and general pathologies related to oral cavity, but also for systemic diseases such as cardiovascular diseases, diabetes, Alzheimer's disease, and others.