Assay Method Information | |
| 17β-HSD13 Rapid-Fire Mass Spectrometry Assay |
Description: | Recombinant human 17β-HSD13 was expressed and purified from sf9 cells at Charles River Labs (Saffron Walden, UK). Leukotriene B4 (Catalog #71160-24-2) and 12-oxoleukotriene B4 (Catalog #20140) were purchased from Cayman Chemicals (Ann Arbor, MI). NAD+ (Catalog #N8285), BSA (Catalog #A7030), DMSO (Catalog #D2650), and Tween-20 (Catalog #11332465001) were purchased from Sigma (St. Louis, MO). Formic acid (Catalog #28905) was from ThermoFisher Scientific and 384 deep well PP microplates (Catalog #784261) were from Greiner Bio-One. In a typical IC50 assay performed in a 384w PP microplate, test compounds (0-100 μM) were incubated with HSD17B13 (80 nM), LTB4 (10 μM), and NAD+ (0.5 mM) in 10 μL assay buffer (20 mM Tris (pH 7.5), BSA (0.005%), and Tween-20 (0.01%)) at RT for 3 h. The assays were quenched by adding 20 μL of 0.15% aqueous formic acid and the plates were frozen at −80° C. RF/MS analysis was performed at PureHoney Technologies (Billerica, MA) on a RapidFire RF300 system (Agilent Technologies, Inc.) coupled to an API 4000 triple quadrupole mass spectrometer (Sciex) equipped with Agilent RapidFire cartridge type A (C4). The mobile phase was 0.09% formic acid and 0.01% trifluoracetic acid in water (Buffer A) and 0.09% formic acid and 0.01% trifluoracetic acid in 80% aqueous acetonitrile (Buffer B). The RapidFire method conditions were the following: 250 ms aspirate, 3000 ms load/desalt, 4000 ms elute, and 500 ms re-equilibrate. RF-MS/MS was performed in negative polarity (−4500 V), the source temperature was 650° C., and gas 1 and gas 2 settings for nitrogen were set to 50. The curtain gas and collision gas were also nitrogen and were set to 20 and 12, respectively. Leukotriene B4 (335.3) and 12-oxoLeukotriene B4 (333.3) SRM transitions were optimized with Discovery Quant software and extracted ion counts for these analytes were determined. |
Affinity data for this assay | |
---|---|
If you find an error in this entry please send us an E-mail |