title: Approaching near real-time biosensing: microfluidic microsphere based biosensor for real-time analyte detection.
abstract: In this study we describe a simple lab-on-a-chip (LOC) biosensor approach utilizing well mixed microfluidic device and a microsphere-based assay capable of performing near real-time diagnostics of clinically relevant analytes such cytokines and antibodies. We were able to overcome the adsorption kinetics reaction rate-limiting mechanism, which is diffusion-controlled in standard immunoassays, by introducing the microsphere-based assay into well-mixed yet simple microfluidic device with turbulent flow profiles in the reaction regions. The integrated microsphere-based LOC device performs dynamic detection of the analyte in minimal amount of biological specimen by continuously sampling micro-liter volumes of sample per minute to detect dynamic changes in target analyte concentration. Furthermore we developed a mathematical model for the well-mixed reaction to describe the near real time detection mechanism observed in the developed LOC method. To demonstrate the specificity and sensitivity of the developed real time monitoring LOC approach, we applied the device for clinically relevant analytes: Tumor Necrosis Factor (TNF)-α cytokine and its clinically used inhibitor, anti-TNF-α antibody. Based on the reported results herein, the developed LOC device provides continuous sensitive and specific near real-time monitoring method for analytes such as cytokines and antibodies, reduces reagent volumes by nearly three orders of magnitude as well as eliminates the washing steps required by standard immunoassays.
authors.affiliation: Department of Pharmaceutical Sciences, Northeastern University, 140 The Fenway, Room 441/ 446, 360 Huntington Avenue, Boston, 02115 MA, USA.
authors.forename: Noa
authors.initials: N
authors.lastname: Cohen
authors.affiliation: Department of Pharmaceutical Sciences, Northeastern University, 140 The Fenway, Room 441/ 446, 360 Huntington Avenue, Boston, 02115 MA, USA.
authors.forename: Pooja
authors.initials: P
authors.lastname: Sabhachandani
authors.affiliation: Centre for Engineering in Medicine, Massachusetts General Hospital, Harvard Medical School, Shriners Burns Institute, Boston, MA, USA.
authors.forename: Alexander
authors.initials: A
authors.lastname: Golberg
authors.affiliation: Department of Pharmaceutical Sciences, Northeastern University, 140 The Fenway, Room 441/ 446, 360 Huntington Avenue, Boston, 02115 MA, USA. Electronic address: konry.tania@gmail.com.
authors.forename: Tania
authors.initials: T
authors.lastname: Konry
mesh_terms: D000906:Antibodies / Q000032:analysis; D015374:Biosensing Techniques / Q000295:instrumentation* / Q000706:statistics & numerical data; D003199:Computer Systems; D016207:Cytokines / Q000032:analysis; D006801:Humans; D007118:Immunoassay / Q000295:instrumentation / Q000706:statistics & numerical data; D046210:Microfluidic Analytical Techniques / Q000295:instrumentation* / Q000706:statistics & numerical data; D008962:Models, Theoretical; D009842:Oligopeptides; D014409:Tumor Necrosis Factor-alpha / Q000032:analysis / Q000037:antagonists & inhibitors / Q000276:immunology
chemical_list: D000906:Antibodies; D016207:Cytokines; D009842:Oligopeptides; D014409:Tumor Necrosis Factor-alpha; C048812:kinetensin
keywords: Antibody; Cytokine; Lab on a chip; Microsphere; Real time detection; TNF-α