Label-free biomarker sensing in undiluted serum with suspended microchannel resonators.
Improved methods are needed for routine, inexpensive monitoring of biomarkers that could facilitate earlier detection and characterization of cancer. Suspended microchannel resonators (SMRs) are highly sensitive, batch-fabricated microcantilevers with embedded microchannels that can directly quantify adsorbed mass via changes in resonant frequency. As in other label-free detection methods, biomolecular measurements in complex media such as serum are challenging due to high background signals from nonspecific binding. In this report, we demonstrate that carboxybetaine-derived polymers developed to adsorb directly onto SMR SiO(2) surfaces act as ultralow fouling and functionalizable surface coatings. Coupled with a reference microcantilever, this approach enables detection of activated leukocyte cell adhesion molecule (ALCAM), a model cancer biomarker, in undiluted serum with a limit of detection of 10 ng/mL.
Department of Biological Engineering and Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
Marcio G
MG
von Muhlen
Norman D
ND
Brault
Scott M
SM
Knudsen
Shaoyi
S
Jiang
Scott R
SR
Manalis
D000327:Adsorption; D015415:Biomarkers / Q000097:blood*; D006801:Humans; D057230:Limit of Detection
D015415:Biomarkers