Attomolar Detection of a Cancer Biomarker Protein in Serum by Surface Plasmon Resonance Using Superparamagnetic Particle Labels

Abstract

Signal amplifiers: Superparamagnetic particle–antibody conjugates were used to detect a cancer biomarker in serum by surface plasmon resonance (SPR) at an unprecedented low level of 10 fg mL−1 (ca. 300 aM). Ultrahigh sensitivity is facilitated by enhanced mass and refractive index from aggregates of 1 μm magnetic particles on the SPR chip. Detailed facts of importance to specialist readers are published as ”Supporting Information”. Such documents are peer-reviewed, but not copy-edited or typeset. They are made available as submitted by the authors. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.