Establishment of ELISA on 384-Well Microplate for AFP, CEA, CA 19-9, CA 15-3, CA 125, and PSA-ACT: Higher Sensitivity and Lower Reagent Cost

The 384-well microplate contains four times as many wells as the regular 96-well microplate. Establishing enzyme linked immunosorbent assay (ELISA) on 384-well microplate should lead to savings in reagents and specimens. To determine that ELISAs on 384-well microplate have acceptable assay precision, ELISAs for tumor markers, including AFP, PSA-ACT, CEA, CA 125, CA 15-3, and CA 19-9, were compared to the same ELISAs established on 96-well microplate, We found that ELISAs established on 384-well microplate had similar sensitivity and covered similar concentration ranges as ELISAs on 96-well microplate. All within-day and day-to-day precisions for the 384-ELISA had %CV less than 10%. Compared to ELISA on 96-well microplate, 384-ELISA used less reagents, less specimen, and exhibited approximately a two-fold increase in sensitivity. Overall cost of the 384-384-ELISA was also greatly reduced. Our results suggest that 384-ELISA is suitable for use in routine clinical laboratories.