Tackling matrix effects in biosensor-based analysis of untreated blood plasma

Area of Science:

• Biomedical Engineering
• Analytical Chemistry
• Biochemistry

Background:

• Human blood plasma is crucial for diagnostics but its complex matrix causes interference.
• Matrix effects, including nonspecific adsorption and endogenous antibody interactions, hinder accurate low-concentration biomarker detection.

Purpose of the Study:

• To investigate and discriminate matrix effects in human blood plasma using surface plasmon resonance (SPR) biosensors.
• To develop and apply a strategy to mitigate matrix effects for sensitive biomarker detection.

Main Methods:

• Utilized surface plasmon resonance (SPR) biosensor technology.
• Implemented a strategy combining sequential injections, single-surface referencing, and anti-immunoglobulin antibodies.
• Applied the strategy for detecting carcinoembryonic antigen (CEA) in undiluted blood plasma.

Main Results:

• Successfully discriminated matrix effects, including nonspecific adsorption and antibody interactions.
• Achieved low detection limits for CEA: 12 ng/mL (direct detection) and 225 pg/mL (sandwich assay with gold nanoparticles).

Conclusions:

• The developed strategy effectively overcomes matrix effects in human blood plasma for SPR-based diagnostics.
• Enables sensitive and accurate detection of cancer biomarkers like CEA in complex biological samples.