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Challenges in urine bioanalytical assays: overcoming nonspecific binding
Allena Ji Ji1, Zhiping Jiang, Yuliya Livson
1Bioanalytical Services, XenoBiotic Laboratories, Inc., 107 Morgan Lane, Plainsboro, NJ 08536, USA. allena_ji@xbl.com
Bioanalysis
|November 19, 2010
Summary
Nonspecific binding in urine bioanalytical assays can be overcome by adding anti-adsorptive agents to collection containers. This systematic approach improves accuracy and precision in drug concentration measurements.
Area of Science:
- Bioanalytical Chemistry
- Pharmaceutical Analysis
Background:
- Urine bioanalytical assays face challenges like nonspecific binding, variable pH, and solubility issues.
- Nonspecific binding leads to underestimation of drug concentrations, impacting assay precision and accuracy.
- Existing methods to overcome adsorption are analyte-specific, lacking a unified approach.
Purpose of the Study:
- To present a common, systematic approach for urine bioanalytical method development.
- To address and overcome the critical issue of nonspecific adsorption in urine assays.
- To summarize practical strategies for improving urine assay reliability.
Main Methods:
- Investigating nonspecific binding of small-molecule drug candidates in urine assays.
- Developing and applying anti-adsorptive agents to urine collection containers.
- Evaluating the effectiveness of agents like bovine serum albumin, CHAPS, and Tweens.
Main Results:
- Adding optimal concentrations of anti-adsorptive agents effectively blocks nonspecific binding.
- A systematic approach simplifies urine method development compared to analyte-specific strategies.
- The study discusses the pros and cons of various anti-adsorptive agents.
Conclusions:
- A universal method development strategy for urine assays is feasible and beneficial.
- Anti-adsorptive agents are crucial for accurate and precise bioanalytical urine testing.
- This work provides a valuable summary for researchers in the field.
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