Notes from the discovery benchMicroplate assays, readers & drug discovery

Discovery in Practice · Reference library

Binding assays in microplate assays

Explore binding assays through measurement principles, assay guidance and practical observations. Follow the questions that match your experiment.

01

Ratio measurements & binding

A ratio combines channels that may respond differently to the experiment. Start with those measurements, then examine tracer behavior and fitted binding results.

  1. Your fluorescence polarization result is hiding two measurements

    A fluorescence-polarization value is calculated from parallel and perpendicular intensity measurements, and the ratio can hide low photon counts or timing mismatch. The article explains how to preserve both channels, interpret intensity and binding curves, and qualify tracer and reader behavior.

    Concepts · Updated
  2. Half the molecules and two thirds of the light

    Binding can change tracer brightness and shift an apparent Kd while the curve still fits beautifully. See the equations, controls and fluorescence data to keep.

    Concepts · Updated
02

Binding & proximity assays

Choose a readout that fits the interaction you want to study. Explore tracer design, proximity measurements and the conditions that affect apparent binding.

  1. Your fluorescent label is part of the experiment

    Choose a fluorescence polarization tracer by matching lifetime to molecular motion, testing the conjugate and checking controls in the actual assay matrix.

    Assays · Updated
  2. One extra carbon can change the binding result

    A one-carbon linker change can alter tracer affinity and assay performance. Learn how to separate binding chemistry from your fluorescence polarization window.

    Assays · Updated
03

Assay method comparisons

Different methods can report different aspects of the same sample. Compare what each format measures before choosing a readout.

  1. Microplate kinase assays: choose the event you need to measure

    ADP production, ATP depletion, substrate phosphorylation and target binding are useful measurements. They are not interchangeable evidence of kinase inhibition.

    Comparisons · Updated

By research topic

LuminescenceFluorescenceTR-FRET & HTRFPlate effectsAbsorbanceBinding assaysScreening equipment