Development of homogeneous plasmonic potency assay using gold nanoparticle immunocomplexes.

Area of Science:

• Nanotechnology
• Biotechnology
• Analytical Chemistry

Background:

• Therapeutic monoclonal antibodies (mAbs) require robust potency assays for quality control.
• Conventional methods like ELISA can be time-consuming and involve multiple steps.
• Gold nanoparticles (AuNPs) offer unique plasmonic properties for sensitive detection.

Purpose of the Study:

• To evaluate a gold nanoparticle (AuNP)-based homogeneous assay for therapeutic monoclonal antibody (mAb) potency measurement.
• To compare the performance of this novel assay with conventional enzyme-linked immunosorbent assay (ELISA).

Main Methods:

• Immobilization of a recombinant human ligand onto AuNPs using functionalized self-assembled monolayers.
• Detection of mAb binding to the immobilized ligand via plasmonic signals in a homogeneous assay format.
• Comparison of assay time, steps, and potency values with a conventional binding ELISA.

Main Results:

• The AuNP-based homogeneous plasmonic immunoassay (HPI) detected binding signals faster than ELISA.
• The HPI generated potency values comparable to those obtained from conventional binding ELISA.
• The assay demonstrated a reduction in assay time and procedural steps.

Conclusions:

• The AuNP-based HPI is a viable and efficient method for therapeutic mAb potency measurement.
• This homogeneous assay offers a faster alternative to ELISA for mAb quality control.
• The HPI has potential for implementation in routine quality control laboratories for therapeutic mAbs.