Development of a portable 3D-printed flow-through passive sampling device free of flow pattern effects

Abstract

A low cost and portable flow-through passive sampling device (PSD) which is not affected by the flow pattern of the sampled aquatic system was developed. Zn2+ was selected as the target analyte in optimizing and testing the device under laboratory conditions using as the source solution (SS) either Zn2+ solutions or environmental waters, spiked with Zn2+. It was demonstrated that the accumulated amount of Zn2+ in all sampling experiments with the newly developed PSD was independent of the flow pattern of the sampled SS which was in contrast with results obtained with previously developed dip-in and shielded dip-in passive samplers. The flow-through PSD consists of an acrylic-based 3D-printed flow-through compartment, a glass vessel containing the receiving solution (RS) and a polymer inclusion membrane which acts as a semipermeable barrier separating the RS from a stream of the sampled water (i.e., SS). The PIM was composed of 35 wt% commercial dinonylnaphthalene sulfonic acid (DNNS), 55 wt% poly(vinyl chloride) and 10 wt% 1-tetradecanol. Though in some of the experiments the SS was propelled through the PSD by a conventional peristaltic pump, unsuitable for use in the field, it was demonstrated that the replacement of the peristatic pump with a small battery-driven piezoelectric micro pump was straightforward and did not affect the performance of the PSD. This finding proves the suitability of the newly developed flow-through PSD as a cost effective and portable tool for passive sampling of environmental waters free of flow pattern effects.