Surface acoustic wave immunosensor for real-time detection of hepatitis B surface antibodies in whole blood samples.
We demonstrate an application of Love wave mode surface acoustic wave (SAW) immunosensor to detect hepatitis B surface antibody (HBsAb) in aqueous conditions. SiO(2) guiding layer was deposited on 36 degrees YX-LiTaO(3) piezoelectric single crystal substrate to protect the electrodes and to trap the acoustic energy near the surface, and hepatitis B surface antigen (HBsAg) was immobilized on the sensing area. The resonance frequency shift was monitored to detect specific binding of HBsAb to immobilized HBsAg. To eliminate the effects of other physical factors except for the mass change, the resonance frequency was compared to that of a reference SAW device coated with bovine serum albumin (BSA) to block binding of HBsAb. The guiding layer thickness with maximum mass sensitivity was found to be 5 microm, which was in agreement with the theoretical calculation, and the center resonance frequency was around 199 MHz. The sensor showed binding specificity to HBsAb and a linear relationship between the frequency shift and the antibody concentration with sensitivity of 0.74 Hz/(pg/microl) and detection limit below 10 pg/microl. In addition, our SAW immunosensor successfully detected HBsAb in whole blood samples without any pretreatment, opening up its applicability in fast label-free protein detection methods.
Lee
Hun Joo
HJ
Emerging Center, Corporate Technology Operations SAIT, Samsung Electronics Co., Ltd., Giheung-gu, Yongin-si, Gyeonggi-do, Republic of Korea.
Namkoong
Kak
K
Cho
Eun Chol
EC
Ko
Christopher
C
Park
Jae Chan
JC
Lee
Soo Suk
SS
D000162:Acoustics; D000818:Animals; D015374:Biosensing Techniques / Q000295:instrumentation* / Q000379:methods / Q000706:statistics & numerical data; D002417:Cattle; D004867:Equipment Design; D006510:Hepatitis B Antibodies / Q000097:blood*; D006514:Hepatitis B Surface Antigens; D006801:Humans; D007118:Immunoassay / Q000295:instrumentation / Q000379:methods / Q000706:statistics & numerical data; D046210:Microfluidic Analytical Techniques; D012680:Sensitivity and Specificity; D012710:Serum Albumin, Bovine; D012822:Silicon Dioxide
D006510:Hepatitis B Antibodies; D006514:Hepatitis B Surface Antigens; D012710:Serum Albumin, Bovine; D012822:Silicon Dioxide