title: Highly sensitive Escherichia coli shear horizontal surface acoustic wave biosensor with silicon dioxide nanostructures.
abstract: Surface acoustic wave mediated transductions have been widely used in the sensors and actuators applications. In this study, a shear horizontal surface acoustic wave (SHSAW) was used for the detection of food pathogenic Escherichia coli O157:H7 (E.coli O157:H7), a dangerous strain among 225 E. coli unique serotypes. A few cells of this bacterium are able to cause young children to be most vulnerable to serious complications. Presence of higher than 1cfu E.coli O157:H7 in 25g of food has been considered as a dangerous level. The SHSAW biosensor was fabricated on 64° YX LiNbO3substrate. Its sensitivity was enhanced by depositing 130.5nm thin layer of SiO2nanostructures with particle size lesser than 70nm. The nanostructures act both as a waveguide as well as a physical surface modification of the sensor prior to biomolecular immobilization. A specific DNA sequence from E. coli O157:H7 having 22 mers as an amine-terminated probe ssDNA was immobilized on the thin film sensing area through chemical functionalization [(CHO-(CH2)3-CHO) and APTES; NH2-(CH2)3-Si(OC2H5)3]. The high-performance of sensor was shown with the specific oligonucleotide target and attained the sensitivity of 0.6439nM/0.1kHz and detection limit was down to 1.8femto-molar (1.8×10-15M). Further evidence was provided by specificity analysis using single mismatched and complementary oligonucleotide sequences.
authors.affiliation: Malaysian Agricultural Research And Development Institute, Serdang 43400, Malaysia; Institute of Nano Electronic Engineering, Universiti Malaysia Perlis, Kangar 01000, Malaysia.
authors.forename: S T
authors.initials: ST
authors.lastname: Ten
authors.affiliation: Institute of Nano Electronic Engineering, Universiti Malaysia Perlis, Kangar 01000, Malaysia; School of Microelectronic Engineering, Universiti Malaysia Perlis, Arau 02600, Malaysia.
authors.forename: U
authors.initials: U
authors.lastname: Hashim
authors.affiliation: Institute of Nano Electronic Engineering, Universiti Malaysia Perlis, Kangar 01000, Malaysia; Institute of Advanced Technology, Universiti Putra Malaysia, Serdang 43400, Malaysia.
authors.forename: S C B
authors.initials: SCB
authors.lastname: Gopinath
authors.affiliation: Institute of Nano Electronic Engineering, Universiti Malaysia Perlis, Kangar 01000, Malaysia.
authors.forename: W W
authors.initials: WW
authors.lastname: Liu
authors.affiliation: Institute of Nano Electronic Engineering, Universiti Malaysia Perlis, Kangar 01000, Malaysia.
authors.forename: K L
authors.initials: KL
authors.lastname: Foo
authors.affiliation: School of Bioprocess Engineering, Universiti Malaysia Perlis, Arau 02600, Malaysia.
authors.forename: S T
authors.initials: ST
authors.lastname: Sam
authors.affiliation: Institute of Advanced Technology, Universiti Putra Malaysia, Serdang 43400, Malaysia.
authors.forename: S F A
authors.initials: SFA
authors.lastname: Rahman
authors.affiliation: Institute of Nano Electronic Engineering, Universiti Malaysia Perlis, Kangar 01000, Malaysia.
authors.forename: C H
authors.initials: CH
authors.lastname: Voon
authors.affiliation: Department of Electrical and Computer Engineering, Engineering Faculty, International Islamic University Malaysia, Kuala Lumpur 53100, Malaysia.
authors.forename: A N
authors.initials: AN
authors.lastname: Nordin
mesh_terms: D015374:Biosensing Techniques / Q000379:methods*; D004269:DNA, Bacterial / Q000737:chemistry / Q000302:isolation & purification*; D004277:DNA, Single-Stranded / Q000737:chemistry / Q000302:isolation & purification*; D019453:Escherichia coli O157 / Q000302:isolation & purification* / Q000472:pathogenicity; D005516:Food Microbiology; D006046:Gold / Q000737:chemistry; D006801:Humans; D049329:Nanostructures / Q000737:chemistry; D012822:Silicon Dioxide / Q000737:chemistry; D013016:Sound
chemical_list: D004269:DNA, Bacterial; D004277:DNA, Single-Stranded; D006046:Gold; D012822:Silicon Dioxide
keywords: Deoxyribonucleic acid (DNA); E. coli O157:H7; Hybridization; Shear horizontal surface acoustic wave (SHSAW); Surface functionalization