Lee, Sang-Myung Hwang, Kyo Seon Yoon, Hyo-Jin Yoon, Dae Sung Kim, Sang Kyung Lee, Yoon-Sik Kim, Tae Song 2024-01-20T21:30:39Z 2024-01-20T21:30:39Z 2021-09-03 2009-06 1473-0197 https://pubs.kist.re.kr/handle/201004/132462 We report two types of signal enhancement strategy derived from the origin of mechanical response, surface stress and mass, of the dynamic mode microcantilever for the detection of PSA at low picogram scales (low femtomolar concentration). The PSA detection at extremely low concentration levels is crucial to the early detection of relapses of prostate cancer after the radical prostatectomy and the detection of breast cancer in patient's serum. There is a clear need for the ultrasensitive detection of PSA via simple and rapid diagnostic tools. From the motives, to increase the sensitivity of the microcantilever, PSA polyclonal antibody (PSA pAb) as an additional surface stress inducer and PSA polyclonal antibody-conjugated silica nanoparticles (pAb-SiNPs) as a mass inducer have been applied to the PSA-captured microcantilevers. From two types of sandwich assay, we could confirm the sensitivity enhancement effects (2 similar to 4 times enhanced at the same concentrations) enough to detect PSA at low picogram levels (LOD of 1 pg/mL or below). Moreover, surface stress due to steric interactions between epitope-specific monoclonal antibodies was assessed to support a signal amplification strategy by stress inducer, and the reduction of signal enhancement due to stiffness increase by the mass inducer was studied to clarify the sensitivity enhancement of the microcantilever by mass inducer. English Royal Society of Chemistry PROSTATE-SPECIFIC ANTIGEN QUARTZ-CRYSTAL-MICROBALANCE SURFACE-PLASMON RESONANCE C-REACTIVE PROTEIN LABEL-FREE DNA DETECTION ELECTRICAL DETECTION CANTILEVER BIOSENSORS IMMOBILIZATION Sensitivity enhancement of a dynamic mode microcantilever by stress inducer and mass inducer to detect PSA at low picogram levels Article 10.1039/b902922b 1 Lab on a Chip, v.9, no.18, pp.2683 - 2690 Lab on a Chip 9 18 2683 2690 scie scopus 000269289600010 2-s2.0-69549118192 Biochemical Research Methods Chemistry, Multidisciplinary Chemistry, Analytical Nanoscience & Nanotechnology Instruments & Instrumentation Biochemistry & Molecular Biology Chemistry Science & Technology - Other Topics Instruments & Instrumentation Article PROSTATE-SPECIFIC ANTIGEN QUARTZ-CRYSTAL-MICROBALANCE SURFACE-PLASMON RESONANCE C-REACTIVE PROTEIN LABEL-FREE DNA DETECTION ELECTRICAL DETECTION CANTILEVER BIOSENSORS IMMOBILIZATION