Sizing silver nanoparticles in biological matrices by spICP-MS

•Feasibility of spICP-MS for the detection and sizing of AgNPs in clinical samples.•AgNPs detection in human matrices blood plasma, sweat, urine, and saliva.•New findings for detecting and monitoring AgNPs in urine, plasma, sweat, and saliva. Advances in the characterization and determination of AgNPs in different matrices, investigations involving biological matrices such as urine, plasma, sweat, and saliva still need more studies for routine application. The present study aimed to investigate silver nanoparticles (AgNPs) sizing in human matrices (blood plasma, sweat, urine, and saliva) by Single Particle Inductively Coupled Plasma Mass Spectrometry (spICP-MS). The influence of sample dilution, NPs concentration, storage time were studied. Blood, plasma, urine and sweat were collected from healthy volunteers aged 20–30 years. The samples were then diluted 1:20 (urine, saliva and plasma) and 1:10 (sweat) in an aqueous solution of AgNPs. After the dilutions, the samples were analyzed by spICP-MS. At the end of the analyzes, the samples were stored at room temperature (25 °C), and another at -5 °C to evaluate the stability of the AgNPs. Higher concentrations of AgNPs in solution caused interference of matrix compatibility due to Ag+ detection by spICP-MS. Storage time up to 144 h for AgNPs 2 µg L − 1 solutions in 1:20 diluted urine and water was suitable for AgNPs detection. Otherwise, AgNPs 2 µg L − 1 did not present a clear signal-background differentiation in a 1:20 plasma diluted solution after a storage time of 144 h. This study provided new knowledge for monitoring of AgNPs in biological samples, helping with the new regulations proposed by Environmental and Health Agencies.