title: A centrifugally actuated point-of-care testing system for the surface acoustic wave immunosensing of cardiac troponin I.
abstract: A fully automated point-of-care testing (POCT) system with a surface acoustic wave (SAW) immunosensor was developed for rapid and sensitive detection of cardiac troponin I (cTnI) in body fluid (plasma and whole blood). The assay, based on gold nanoparticle sandwich immunoassay and subsequent gold staining, was performed on the SAW immunosensor packaged inside a disposable microfluidic cartridge. The entire fluidic process, including plasma separation, reagent transport, metering, and mixing, was carried out by controlling the centrifugal force acting on the rotating cartridge and laser-irradiated ferrowax microvalves. On investigation of sensor response to various cTnI concentrations, the system exhibited a high performance with a detection limit of 6.7 pg mL(-1), and the coefficient of variation was less than 10% over the entire test range (10 pg mL(-1) to 25 ng mL(-1)). On comparing this POCT system with a clinically utilized system in a physical laboratory (Centaur® XP; Siemens), a correlation coefficient of 0.998 was found, validating the diagnostic capability of the SAW immunosensor.
authors.affiliation: Bio Research Center, Samsung Advanced Institute of Technology, Samsung Electronics Co., Ltd., San 14-1, Nongseo-dong, Giheung-gu, Yongin-si, Gyeonggi-do, Republic of Korea.
authors.forename: Woochang
authors.initials: W
authors.lastname: Lee
authors.forename: Jaeyeon
authors.initials: J
authors.lastname: Jung
authors.forename: Young Ki
authors.initials: YK
authors.lastname: Hahn
authors.forename: Sang Kyu
authors.initials: SK
authors.lastname: Kim
authors.forename: Yeolho
authors.initials: Y
authors.lastname: Lee
authors.forename: Joonhyung
authors.initials: J
authors.lastname: Lee
authors.forename: Tae-Han
authors.initials: TH
authors.lastname: Lee
authors.forename: Jin-Young
authors.initials: JY
authors.lastname: Park
authors.forename: Hyejung
authors.initials: H
authors.lastname: Seo
authors.forename: Jung Nam
authors.initials: JN
authors.lastname: Lee
authors.forename: Jin Ho
authors.initials: JH
authors.lastname: Oh
authors.forename: Youn-Suk
authors.initials: YS
authors.lastname: Choi
authors.forename: Soo Suk
authors.initials: SS
authors.lastname: Lee
mesh_terms: D004867:Equipment Design; D006046:Gold / Q000737:chemistry; D006801:Humans; D007118:Immunoassay / Q000295:instrumentation*; D057230:Limit of Detection; D046210:Microfluidic Analytical Techniques / Q000295:instrumentation*; D053758:Nanoparticles / Q000737:chemistry; D019095:Point-of-Care Systems; D013016:Sound; D019210:Troponin I / Q000097:blood*
chemical_list: D019210:Troponin I; D006046:Gold