Scientific Advantages Of Picoliter Dispensing For Dose-Response Analyses

Digital dispensing provides the ability to form dose-response analyses without the use of serial dilution, instead forming the series of doses by directly placing the appropriate number of picoliter droplets into each well. This greatly simplifies work flows by eliminating intermediate steps in forming dose series. This is also called direct dilution since every well is given its dose directly from the stock, so that the dose in every well is independent of the dose in any other well.

Picoliter dispensing is accomplished non-invasively by moving droplets through the air into either dry or previously filled wells, and is effective for either enzymatic or cellular assays, because ultrasmall droplets quickly mix to eliminate exposing cells to large concentrations of DMSO.

In addition to the economic advantages for improving speed, precision, compound usage and waste, this method has numerous scientific advantages. These include simple drug-drug interaction (synergy) experiments and dose randomization to reduce edge effects. Additionally, extremely finely spaced dosages, and doses targeted to known IC50 or EC50 values are enabled by digital technology. The advantages of using these "tuned" doses for dose-response studies is the subject of this poster. Finely spaced and targeted doses lead to more precise determination of Hill slopes and IC50 estimates.