High-Throughput Aliquoting of the HTS Library

The replication of microliter or nanoliter aliquots of compound solutions in DMSO in high-density plates with low well-to-well variability of the aliquot volume is a demanding liquid-handling task. The challenge is set forth by several prerequisites and requirements  

One 384-well pipettor is sufficient for the preparation of aliquots in 384-well plates. For preparation of aliquots in 1536-well plates, four 384-well pipettors are used for transfer of the aliquots from four 384-well source plates to 1536-well target plates. 

We also investigated the tip-wash efficiency using two types of carryover test experiments the first experiment uses source plates filled with pure DMSO and intervening source plates filled with fluorescein solution in DMSO. The measured fluorescein carryover from the source plate of the previous replication cycle to the target plates of the subsequent replication cycle was found to be less than 0.004% ( 4 X 10 ). In the second test experiment, six different compound solutions in DMSO were processed on the plate-replication system. The carryover of the compounds from the previous source plate was determined in the target plates of the subsequent replication cycle using LC/MS/MS analytics. The measured compound carryover from the source plate of the previous replication cycle to the target plates of the subsequent replication cycle was always smaller than 0.008% ( 8 X 10 ).T 

3 A Microfluidic Well Plate for High-Throughput Solid/Liquid Separations 

Proteomics is a modem parallel approach for investigating protein expression in experimental systems. In pharmaceutical research, this methodology is used to accelerate the discovery of novel drug targets and biomarkers. Among the several possible techniques for the study of proteomes, the combination of two-dimensional polyacrylamide electrophoresis with mass spectrometric identification of the separated proteins has gained wide popularity. This technique involves the analysis of vast numbers of small gel spots that are excised from two-dimensional protein separation 

---