A single pipette tip washing protocol is sufficient to reduce carryover in a panel of 53 drug analytes to undetectable levels via ELISA

Pipette tip washing is a valuable approach to reduce plastic waste in the laboratory, to reduce spend on plastic consumables and to manage a sustainable supply of tips at the point of use. The TipNovus Mini is a commercial instrument to wash pipette tips for reuse. One challenge in pipette tip washing is the development of a single wash protocol that can efficiently wash a broad range of analytes to undetectable levels while minimizing water and other reagent use. Many relevant toxicological samples contain analytes with varying degrees of solubility which may require different solvents and protocols to efficiently clean to undetectable levels. Here we present a single wash protocol performed on the TipNovus Mini that eliminates the carryover of a panel of 53 drug analytes in urine samples as detected by ELISA. We additionally evaluated whether using brand new pipette tips or washed tips using this protocol had any functional difference on the ELISA detection of Azeperone in urine samples. We found no significant difference in the functional results of the assay when using washed pipette tips. We conclude that pipette tip washing using the commercial TipNovus platform can be incorporated into toxicological workflows with minimal risk of analyte carryover interfering with downstream results.