Protein L-Ligand Leakage Elisa

The Medicago Protein L-Ligand Leakage Elisa kit has been designed to detect and quantify Protein L in Immunoglobulin (Ig) or Ig-fragment containing solutions, e.g. eluates from Protein L affinity chromatography. The kit was developed as a complement to Cytiva’s affinity chromatography medium Capto L.

Easy, stepwise procedure
The Protein L Ligand Leakage Elisa kit is easy to use. It contains all the components necessary for your daily lab routine and is based on a simple stepwise procedure. The concentration of Protein L in your samples is calculated and presented as a calibration curve indicating any ligand leakage in your eluates.

Verification of pharmaceutical processes
The kit is for verifying affinity chromatography process quality in purification of pharmaceuticals using chromatography. A low leakage level of Protein L in the column used is proof that both the medium and the process as such are performing as expected. Compared to developing your own protocols, using this validated detection kit is an easy and secure way for researchers and manufacturers to continuously check for leakage and to ensure process quality.

The kit comes as a sandwich ELISA with microtiter strips coated with an affinity purified anti-Protein L IgY-antibody. In this assay, samples are boiled to separate the Ig/Ig-fragments from the Protein L in the solution, centrifuged, and incubated in the strip wells. The bound Protein L is then detected by adding a horseradish peroxidase (HRP)-conjugated anti-Protein L IgY antibody. Substrate is added to induce a color change which is proportional to the amount of bound Protein L from the sample. The color change is quantified spectrophotometrically at 450nm by using a plate reader. The amount of Protein L in the sample is determined by using a standard curve prepared in a reference sample. The reference sample should have the same concentration of Ig or Ig-fragments and preferably the same buffer composition as the elution samples from the Protein L affinity chromatography medium. However, it should be prepared using another purification strategy, e.g. ion exchange chromatography. Once a reference sample is created it can be aliquoted and used for several different protein L ELISA assays. 

Applications
Determination of leakage levels of Protein L in Protein L-medium purification of intact immunoglobulin or immunoglobulin fragments (Ig or Ig fragments). Some fab samples may require optimization. Currently there is no protocol available for sdab molecules. 

Shipping and storage
The product is shipped cooled (+2°C to +8°C) except the Protein L reference which is shipped frozen (-20°C). On arrival store components cooled ( +2°C to +8°C ) except the Protein L reference which should be stored at -20/-80°C.
Strips (96 wells): Store unused strips in sealed bag at +2°C to +8°C .
HRP-conjugated anti Protein L pAb and EC-Blue Enhanced TMB-substrate: Store protected from light.
Protein L reference: Store in working aliquots to avoid repeated freezing/thawing.