Highly Effective Synthetic Polymer-Based Blockers of Non-Specific Interactions in Immunochemical Analyses

Area of Science:

• Biomaterials Science
• Diagnostic Assay Development
• Polymer Chemistry

Background:

• In vitro diagnostics suffer from non-specific interactions, increasing background noise and reducing assay reliability.
• Bovine serum albumin (BSA) is a common blocker but has drawbacks, including batch variability and potential RNase contamination.

Purpose of the Study:

• To develop effective synthetic alternatives to BSA for blocking non-specific interactions in diagnostic assays.
• To evaluate the performance of novel amphiphilic, water-soluble synthetic copolymers as BSA replacements.

Main Methods:

• Synthesis of amphiphilic, water-soluble copolymers based on N-2-(hydroxypropyl)methacrylamide (HPMA) and poly(oxazoline)s.
• Incorporation of two different hydrophobic anchors into HPMA-based polymers to enhance blocking capacity.
• Evaluation of polymer performance using sandwich ELISA for human thyroid-stimulating Hormone in patient samples.

Main Results:

• HPMA-based polymers with two hydrophobic anchors demonstrated superior blocking capacity compared to other designs.
• Polymers synthesized via free radical polymerization with broader dispersity showed improved surface coverage.
• The designed synthetic copolymers fully replaced BSA in ELISA without negatively impacting assay results.

Conclusions:

• Developed synthetic copolymers are highly effective BSA alternatives for blocking non-specific interactions in diagnostic assays.
• These synthetic materials are animal pathogen-free, offering enhanced safety and reproducibility.
• The novel polymers represent a significant advancement for improving the reliability and development of in vitro diagnostics.