Design of Au Nanoparticles Amplified Piezoelectric Immunosensor Array to Detect Bone Sialoprotein
With the unique properties of Au nanopaticles,a microarray was designed using AT-cut 10 MHz quartz crystal to detect bon sialoprotein(BSP) expression from clinical serum.Monoclonal antibody of BSP was immobilized by AuNPs/sulfosuccinimidyl-6-[3'-(2-pyridyldithio)-propionamido]hexanoa(Sulfo-LC-SPDP) self-assembly.The serum BSP was detected after immunoreaction.With two different immobilizations,the frequency shift is higher via Au nanopaticles than that without Au nanopaticles.The detection of reference standard serum at dilution of 1:9,1:8,1:7,1:6,1:5,1:4,1:3,and 1:2 showed that the serum dilution ranged from 1:9 to 1:2.Constructed BSP nano-immunosensor array exhibited good linear relationship with serum detection.The linear equation was ΔF = 872.66c-58.258(correlation coefficient = 0.9737).Furthermore,the nano-immunosensor array had higher accuracy and sensitivity than the immunosensor array without Au nanopaticles.The BSP expression level of breast cancer and osteoporosis serum was both significantly higher than that of healthy serum using BSP nano-piezoelectric immunosensor array(P 0.05).Au nanopaticles not only enhanced the antibody immobilization,but also amplified the response of immunoreaction.The BSP nano-piezoelectric immunosensor array has simple structure,high sensitivity and specificity,and can be used for quantitative detection of serum BSP.