An Investigation of Liquid Carryover and Sample Residual for a High-Throughput Flow Cytometer Sample Delivery System

Abstract

The phenomenon of intersample contamination in air-segmented continuous-flow assays has been studied for many years, and new uses are being found for these sampling techniques every day. One application that has been developed recently employs a flow cytometer to conduct high-throughput screening assays of biological compounds. We have explored the sources of intersample contamination in the system and shown how methods developed previously can be applied to describe these phenomena. Using a simple model, we were able to accurately measure liquid film thickness in the sample tubing and demonstrate the effects of intersample contamination in a flow cytometer assay. Also, measures have been taken to reduce the level of intersample contamination in cytometric screening assays, helping to make the system a more viable tool for drug screening applications.

Multiplexed mass cytometry profiling of cellular states perturbed by small-molecule regulators

“…Drug screening applications for FBFC have been implemented by hardware 30, 31 or by sample multiplexing with fluorescent cell barcoding (FCB) 32, 33 . With these adaptations, FBFC has become a powerful tool for drug screening and pre-clinical analysis.…”

Simultaneous in vitro molecular screening of protein-peptide interactions by flow cytometry, using six Bcl-2 family proteins as examples

“…One particular problem, fluid carryover of fluorescent compound from one well to the next, was addressed in part by the seventh uncoated bead set to assist in identifying nonspecific fluorescence for a given well. The fluid carryover depends in part upon the length of the delivery tubing in HyperCyt™ 17 , and alternate delivery geometries are under exploration. Beads coated with inactive proteins from the multiplex family may serve as complementary controls.…”

High-Throughput Screening with HyperCyt® Flow Cytometry to Detect Small Molecule Formylpeptide Receptor Ligands

“…10 Fluid carryover is more pronounced than particle carryover, requiring 1 or more postsampling rinse steps to eliminate. 10,11 However, in end point assays, fluid compound carryover occurs only during the time that samples are being transported from microplate to flow cytometer. The 4Pep blocking peptide, in well 12 of each microplate row, had a K d similar to the fluorescent peptide (~3 nM) and was used at a 100-fold higher concentration (150 nM).…”