title: Examination of edge effects with different storage conditions of preplated dimethyl sulfoxide nanospots in ChemLib 1,536- and 3,456-well assay-ready plates.
abstract: For ultra-high-throughput screening, 10-30 nl of compound dissolved in 75% dimethyl sulfoxide (DMSO)/25% water (vol/vol) is spotted into 1,536- and 3,456-well ChemLib plates (Aurora Biotechnologies, Carlsbad, CA) and stored appropriately for a short time before screening. Although this practice eliminates the compound plating bottleneck, plated volumes of DMSO slowly evaporate from assay wells if plates are not properly stored in the interim. Since many assays are sensitive to DMSO concentrations, even slight evaporation may cause intra-plate variation and thus decrease assay quality. Using a cytochrome P450 3A4 Vivid Blue assay (Invitrogen, Carlsbad), we investigated the rate, pattern, and quantity of evaporation over a 1-year time frame to identify best practices for long-term (i.e., 6 months or greater) storage of assay-ready compound plates. Our findings regarding evaporation at plate edges indicate that nanospots preplated in ChemLib 1,536- or 3,456-well plates are best stored at -80 degrees C, in a bag, with or without the outer evaporation wells filled or at -20 degrees C, in a bag, with evaporation wells filled.
authors.affiliation: Department of Assay Technologies, Pfizer Global Research and Development, Michigan Laboratories, Ann Arbor, Michigan, USA.
authors.forename: Benjamin A
authors.initials: BA
authors.lastname: Turner
authors.forename: Brad P
authors.initials: BP
authors.lastname: Evans
authors.forename: Tania T
authors.initials: TT
authors.lastname: Pearson
authors.forename: Timothy K
authors.initials: TK
authors.lastname: Braden
authors.forename: Scott C
authors.initials: SC
authors.lastname: Wise
mesh_terms: D001681:Biological Assay; D051544:Cytochrome P-450 CYP3A / Q000378:metabolism; D004121:Dimethyl Sulfoxide / Q000737:chemistry / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004353:Drug Evaluation, Preclinical / Q000379:methods* / Q000639:trends; D005456:Fluorescent Dyes / Q000737:chemistry; D005470:Fluorometry / Q000295:instrumentation* / Q000379:methods*; D006813:Humidity; D007202:Indicators and Reagents / Q000737:chemistry; D054118:Nanospheres / Q000032:analysis / Q000737:chemistry; D011309:Preservation, Biological / Q000379:methods*; D012034:Refrigeration; D012371:Robotics; D012997:Solvents / Q000737:chemistry; D013696:Temperature; D013997:Time Factors; D014835:Volatilization
chemical_list: D005456:Fluorescent Dyes; D007202:Indicators and Reagents; D012997:Solvents; D051544:Cytochrome P-450 CYP3A; C510163:CYP3A4 protein, human; D004121:Dimethyl Sulfoxide