Whole serum BSA antibody screening using a label-free biophotonic nanoparticle array

Area of Science:

• Biophotonics
• Biosensing
• Nanotechnology

Background:

• Antibodies against bovine serum albumin (aBSA) are crucial biomarkers.
• Developing sensitive and rapid detection methods for aBSA is important for diagnostics.
• Biophotonic arrays offer a platform for high-throughput biomolecule detection.

Purpose of the Study:

• To develop and validate a biophotonic array for screening and quantifying aBSA in whole serum.
• To compare the performance of gold nanoparticle functionalized surfaces with continuous gold surfaces for aBSA detection.

Main Methods:

• A 96-spot biophotonic array was fabricated with in situ synthesized 130-nm gold nanoparticles.
• Gold nanoparticle surfaces were functionalized with bovine serum albumin (BSA), fibrinogen, and immunoglobulin G (IgG).
• Kinetic analysis of time-dependent light scattering was used to determine aBSA concentration and binding parameters.

Main Results:

• The biophotonic array successfully screened aBSA from whole leporine anti-serum.
• Kinetic parameters for aBSA-BSA interaction were determined: k(a)=(1.3 +/- 0.3) x 10(5) M(-1) s(-1), k(d)=(4 +/- 2) x 10(-4) s(-1), and K(D)=3 nM.
• The array achieved a sensitivity of 1 microg ml(-1) for aBSA and demonstrated higher sensitivity than continuous gold surfaces.

Conclusions:

• The gold nanoparticle-based biophotonic array is a sensitive and effective platform for detecting aBSA in serum.
• The nanoparticle surface enhances sensitivity due to improved refractive index contrast in plasmon fields.
• This method offers a promising approach for rapid and accurate aBSA quantification.