High-Throughput a1-Acid Glycoprotein Binding Assay

The 20 min high-throughput assay estimates the binding of drugs to a₁-acid glycoprotein (AGP) and is essential for predicting plasma protein binding under disease states.

The ready-to-go assay kit measures the affinity constant (KD) of drugs to AGP and thereby allows the calculation of AGP under disease dependent protein concentration ranging from 0.4 to 2.8 g/L.

Off-the-shelf a₁-Acid Glycoprotein Binding Assay Kit

Sovicell has developed a perfect ready-made assay for estimating the binding of drugs to a₁-acid glycoprotein (AGP) – the TRANSIL AGP Binding Kit.

The rapid, high-throughput assay kit consists of ready-to-use 96-well microtiter plates. Each plate can be used for measuring AGP binding of up to 12 compounds. When used in conjunction with TRANSIL HSA Binding Kit it is possible to obtain an accurate prediction of plasma protein binding in a highly controlled and reproducible assay environment.

Modeling plasma protein binding under a broad range of disease conditions

Human a1-acid glycoprotein and human serum albumin (HSA) are the most important plasma binding proteins. Sovicell has developed binding assays for both proteins, under its TRANSIL trademark.

The TRANSILXL AGP Binding Kit employs immobilized AGP with a random orientation. This makes sure that all binding sites are available and that the assay reproduces exactly the binding of drugs to AGP in solution. The TRANSIL AGP Binding Assay is specifically designed to predict plasma protein binding in combination with the TRANSIL HSA Binding Assay and to model plasma protein binding under a broad range of disease conditions.

Distinctions in relation to plasma binding arise through variations in plasma composition, due to lipids blocking binding sites in native plasma, and occasionally due to binding to other plasma proteins with low abundance. AGP can contribute primarily to plasma binding of acidic or neutral drugs.

Estimating the binding of drugs to a₁-acid glycoprotein (AGP) with the five-step assay kit

The TRANSIL AGP Binding Assay Kit estimates the binding of drugs in only 5 steps:

1. addition of drug candidate
2. mixing and incubating for 12 minutes
3. removal of beads by centrifugation
4. sampling of supernatant
5. quantification of the drug candidate

Capabilities

Detection systems:

• LC/MS/MS
• Scintillation counting
• Others

Parameters estimated and predicted:

• Affinity constant (KD) of drugs to AGP
• Unbound fraction of drug in AGP solution
• Unbound fraction of drug in plasma
• Concentration dependet plasma protein binding

Features & Benefits of the High-Throughput a1-Acid Glycoprotein Binding Assay

• Fast, requires only 20 minutes total assay time
• Accurately measures the affinity of drug candidates to a1-acid glycoprotein (AGP) to predict plasma protein binding under diverse disease conditions
• Ready-to-go 96-well microtiter plate format generating reliable highly reproducible results and robust correlation to equilibrium dialysis method.
• Fully quality-controlled binding estimates.
• Rapid compound quantification due to immobilized plasma proteins
• Kit includes a spreadsheet for calculation of final results and traffic light system for data quality rating

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For more information please contact Sovicell today.