3D printed spinning cup-shaped device for immunoaffinity solid-phase extraction of diclofenac in wastewaters

This article reports current research efforts towards designing bespoke microscale extraction approaches exploiting the versatility of 3D printing for fast prototyping of novel geometries of sorptive devices. This is demonstrated via the so-called 3D printed spinning cup-based platform for immunoextraction of emerging contaminants using diclofenac as a model analyte. A new format of rotating cylindrical scaffold (containing a semispherical upper cavity) with enhanced coverage of biorecognition elements, and providing elevated enhancement factors with no need of eluate processing as compared with other microextraction stirring units is proposed. Two distinct synthetic routes capitalized upon modification of the acrylate surface of stereolithographic 3D printed parts with hexamethylenediamine or branched polyethyleneimine chemistries were assayed for covalent binding of monoclonal diclofenac antibody.Under the optimized experimental conditions, a LOD of 108 ng L^-1 diclofenac, dynamic linear range of 0.4-1,500 µg L^-1, and enrichment factors > 83 (for near-exhaustive extraction) were obtained using liquid chromatography coupled with UV-Vis detection. The feasibility of the antibody-laden device for handling of complex samples was demonstrated with the analysis of raw influent wastewaters with relative recoveries ranging from 102 to 109%. By exploiting stereolithographic 3D printing, up to 36 midget devices were fabricated in a single run with an estimated cost of mere 0.68 euros per 3D print and up to 16 €/device after the incorporation of the monoclonal antibody.