title: Polysilicon nanogap lab-on-chip facilitates multiplex analyses with single analyte.
abstract: Rationally designed biosensing system supports multiplex analyses is warranted for medical diagnosis to determine the level of analyte interaction. The chemically functionalized novel multi-electrode polysilicon nanogap (PSNG) lab-on-chip is designed in this study, facilitates multiplex analyses for a single analyte. On the fabricated 69nm PSNG, biocompatibility and structural characteristics were verified for the efficient binding of Human Chorionic Gonadotropin (hCG). With the assistance of microfluidics, hCG sample was delivered via single-injection to 3-Aminopropyl(triethoxy)silane (APTES) and Glycidoxypropyl(trimethoxy)silane (GPMS) modified PSNG electrodes and the transduced signal was used to investigate the dielectric mechanisms for multiplex analyses. The results from amperometric response and impedance measurement delivered the scale of interaction between anti-hCG antibody and hCG that exhibited 6.5 times higher sensitivity for the chemical linker, APTES than GPMS. Under optimized experimental conditions, APTES and GPMS modified immunosensor has a limit of detection as 0.56mIU/ml and 2.93mIU/ml (at S/N=3), with dissociation constants (Kd) of 5.65±2.5mIU/ml and 7.28±2.6mIU/ml, respectively. These results suggest that multiplex analysis of single target could enhance the accuracy of detection and reliable for real-time comparative analyses. The designed PSNG is simple, feasible, requires low sample consumption and could be applied for any given multiplex analyses.
authors.affiliation: Biomedical Nano Diagnostics Research Group, Institute of Nano Electronic Engineering (INEE), Universiti Malaysia Perlis (UniMAP), Kangar, Perlis, Malaysia.
authors.forename: Sharma Rao
authors.initials: SR
authors.lastname: Balakrishnan
authors.affiliation: Biomedical Nano Diagnostics Research Group, Institute of Nano Electronic Engineering (INEE), Universiti Malaysia Perlis (UniMAP), Kangar, Perlis, Malaysia; School of Microelectronic Engineering, University Malaysia Perlis (UniMAP), Kuala Perlis, Perlis, Malaysia. Electronic address: uda@unimap.edu.my.
authors.forename: U
authors.initials: U
authors.lastname: Hashim
authors.affiliation: Biomedical Nano Diagnostics Research Group, Institute of Nano Electronic Engineering (INEE), Universiti Malaysia Perlis (UniMAP), Kangar, Perlis, Malaysia.
authors.forename: Subash C B
authors.initials: SC
authors.lastname: Gopinath
authors.affiliation: School of Microelectronic Engineering, University Malaysia Perlis (UniMAP), Kuala Perlis, Perlis, Malaysia.
authors.forename: P
authors.initials: P
authors.lastname: Poopalan
authors.affiliation: Department of Obstetrics and Gynaecology, Hospital Tuanku Fauziah, Kangar, Perlis, Malaysia.
authors.forename: H R
authors.initials: HR
authors.lastname: Ramayya
authors.affiliation: Biomedical Nano Diagnostics Research Group, Institute of Nano Electronic Engineering (INEE), Universiti Malaysia Perlis (UniMAP), Kangar, Perlis, Malaysia.
authors.forename: P
authors.initials: P
authors.lastname: Veeradasan
authors.affiliation: Biomedical Nano Diagnostics Research Group, Institute of Nano Electronic Engineering (INEE), Universiti Malaysia Perlis (UniMAP), Kangar, Perlis, Malaysia.
authors.forename: R
authors.initials: R
authors.lastname: Haarindraprasad
authors.affiliation: Biomedical Nano Diagnostics Research Group, Institute of Nano Electronic Engineering (INEE), Universiti Malaysia Perlis (UniMAP), Kangar, Perlis, Malaysia.
authors.forename: A R
authors.initials: AR
authors.lastname: Ruslinda
mesh_terms: D055910:Antibodies, Immobilized / Q000737:chemistry*; D015374:Biosensing Techniques / Q000295:instrumentation*; D006063:Chorionic Gonadotropin / Q000032:analysis*; D004566:Electrodes; D004867:Equipment Design; D006801:Humans; D007118:Immunoassay / Q000295:instrumentation; D056656:Lab-On-A-Chip Devices; D057230:Limit of Detection; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure; D012821:Silanes / Q000737:chemistry; D012825:Silicon / Q000737:chemistry*
chemical_list: D055910:Antibodies, Immobilized; D006063:Chorionic Gonadotropin; D012821:Silanes; D012825:Silicon
keywords: Human Chorionic Gonadotropin; Lab-on-chip; Multiplexed analysis; Organosilane; Polysilicon nanogap