Determination of human growth hormone in human serum samples by surface plasmon resonance immunoassay.
A surface plasmon resonance immunoassay has been developed to determine human growth hormone (hGH) directly and without pre-treatment in human serum samples. A binding inhibition immunoassay was employed. Antibody concentration, assay buffer and regeneration solution have been optimized in order to reach the best performance and the lower non-specific binding of the matrix components to the sensor surface. The lowest detection limit was 6 ng/mL, with a working range covering the physiological range. Reproducibility of the assay was excellent with both intra-assay and inter-assay relative standard deviations <5%, while a variation of 2.19% was obtained employing different sensor chips. Reutilization of the sensor surface allows its continuous use over 50 measurements with a signal drop <20%. The SPR immunoassay results were validated using enzyme-linked immunosorbent assay (ELISA) showing an excellent correlation (R(2)=0.985). A portable and fully automated system (Sensia SL) was employed in this work. This is the first SPR biosensor assay capable of detecting relevant concentrations of a clinical analyte in serum. This study shows the potentials of this device as a diagnostic tool for the detection of multiple clinical analytes.
Treviño
J
J
Grupo de Nanobiosensores y Biofísica Molecular, Centro de Investigación en Nanociencia y Nanotecnología (CIN2: CSIC-ICN), ETSE, Campus UAB, Bellaterra, Barcelona, Spain. juan.trevino@cin2.es
Calle
A
A
Rodríguez-Frade
J M
JM
Mellado
M
M
Lechuga
L M
LM
D000906:Antibodies; D015374:Biosensing Techniques / Q000379:methods; D019382:Human Growth Hormone / Q000097:blood*; D006801:Humans; D007118:Immunoassay / Q000379:methods*; D020349:Surface Plasmon Resonance / Q000379:methods*
D000906:Antibodies; D019382:Human Growth Hormone