Surface plasmon resonance biosensor for parallelized detection of protein biomarkers in diluted blood plasma.
Surface plasmon resonance (SPR) biosensor for high-throughput screening of protein biomarkers in diluted blood plasma is reported. The biosensor combines a high-resolution SPR imaging sensor and a high-density protein array with low-fouling background. The SPR imaging sensor utilizes polarization contrast and advanced referencing and provides a total of 120 sensing areas (each 200 μm×150 μm). Antibodies are immobilized on the sensing areas via hybridization of antibody-oligonucleotide conjugates to thiolated complementary oligonucleotides microspotted on the sensor surface (DNA-directed immobilization). A low-fouling background is achieved by covalent immobilization of bovine serum albumin to carboxyl-terminated thiols filling the areas among the thiolated oligonucleotides and outside the sensing areas. The biosensor was evaluated for detection of protein biomarkers relevant to cancer diagnostics--human chorionic gonadotropin (hCG) and activated leukocyte cell adhesion molecule (ALCAM) both in buffer and in 10% blood plasma. Limits of detection as low as 45 ng/mL (ALCAM) and 100 ng/mL (hCG) were achieved in blood plasma samples.
Piliarik
Marek
M
Institute of Photonics and Electronics AS CR v.v.i., Chaberská 57, CZ-18251 Prague 8, Czech Republic.
Bocková
Markéta
M
Homola
Jiří
J
D000818:Animals; D055910:Antibodies, Immobilized; D015703:Antigens, CD / Q000097:blood; D015415:Biomarkers / Q000097:blood*; D014408:Biomarkers, Tumor / Q000097:blood; D001798:Blood Proteins / Q000032:analysis*; D002417:Cattle; D015816:Cell Adhesion Molecules, Neuronal / Q000097:blood; D006063:Chorionic Gonadotropin / Q000097:blood; D004867:Equipment Design; D005326:Fetal Proteins; D006801:Humans; D055767:Immobilized Proteins; D057230:Limit of Detection; D009369:Neoplasms / Q000097:blood / Q000175:diagnosis; D009841:Oligonucleotides; D012031:Refractometry; D012710:Serum Albumin, Bovine; D020349:Surface Plasmon Resonance / Q000295:instrumentation* / Q000379:methods / Q000706:statistics & numerical data; D013873:Thionucleotides; D020410:Activated-Leukocyte Cell Adhesion Molecule
D055910:Antibodies, Immobilized; D015703:Antigens, CD; D015415:Biomarkers; D014408:Biomarkers, Tumor; D001798:Blood Proteins; D015816:Cell Adhesion Molecules, Neuronal; D006063:Chorionic Gonadotropin; D005326:Fetal Proteins; D055767:Immobilized Proteins; D009841:Oligonucleotides; D012710:Serum Albumin, Bovine; D013873:Thionucleotides; C105613:ALCAM protein, human; D020410:Activated-Leukocyte Cell Adhesion Molecule