Kui Jiao

Qingdao University of Science and Technology, Tsingtao, Shandong Sheng, China

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Publications (176)388.49 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: In order to achieve the large direct electrochemical signals of guanine and adenine, an urgent request to explore novel electrode materials and interfaces has been put forward. In this paper, a poly(xanthurenic acid, Xa)-reduced graphene oxide (PXa-ERGNO) interface, which has rich negatively charged active sites and accelerated electron transfer ability, was fabricated for monitoring the positively charged guanine and adenine. Scanning electron microscopy, Fourier transform infrared spectroscopy, Raman spectra, X-ray photoelectron spectroscopy, cyclic voltammetry, electrochemical impedance spectroscopy, and differential pulse voltammetry were adopted to characterize the morphology and prove the electrochemical properties of the prepared interface. The PXa-ERGNO interface with rich negative charge and large electrode surface area was an excellent sensing platform to prompt the adsorption of the positively charged guanine and adenine via strong π-π* interaction or electrostatic adsorption. The PXa-ERGNO interface exhibited prominent synergistic effect and good electrocatalytic activity for sensitive determination of guanine and adenine compared with sole PXa or ERGNO modified electrode. The sensing platform we built could be further applied in the adsorption and detection of other positively charged biomolecules or aromatic molecules.
    ACS Applied Materials & Interfaces 07/2014; · 5.01 Impact Factor
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    ABSTRACT: In this paper, a type of direct DNA impedance detection using the self-redox signal change of sulfonated polyaniline (SPAN) enhanced by graphene oxide (GNO) was reported, here SPAN is a copolymer obtained from aniline and m-aminobenzenesulfonic acid. The resulting nanocomposite was characterized by scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, cyclic voltammetry, and electrochemical impedance spectroscopy. The π-π planar structure of GNO and the carboxyl groups on the surface of GNO ensured it could act as an excellent substrate for adsorption and polymerization of aniline monomer. Because of the existence of GNO, the electrochemical activities of SPAN were enhanced obviously. Owing to abundant sulfonic acid groups, the resulting nanocomposite showed obvious self-redox signal even at physiological pH, which is beneficial for biosensing field. DNA probes with amine groups could be covalently attached to the modified electrode surface through the acyl chloride cross-linking reaction of sulfonic groups and amines. When the flexible probe DNA was successfully grafted, the electrode was coated and electron transfer between electrode and buffer was restrained. Thus, the inner impedance value of SPAN (rather than using outer classic EIS probe, [Fe(CN)6]3-/4-) increased significantly. After hybridization, the rigid helix opened the electron channel, which induced impedance value decreased dramatically. As an initial application of this system, the PML/RARA fusion gene sequence formed from promyelocytic leukemia (PML) and retinoic acid receptor alpha (RARA) was successfully detected.
    ACS Applied Materials & Interfaces 10/2013; · 5.01 Impact Factor
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    ABSTRACT: In this paper, the comparison of two kinds of electrochemically reduced graphene oxide (ERGNO) and zirconia composites, obtained by one-step (ZrO2-ERGNO) and stepwise (ZrO2/ERGNO) electrodeposition for DNA sensing, is systematically studied. The resulting composites were characterized by scanning electron microscopy, cyclic voltammetry, and differential pulse voltammetry. The results indicated that the ZrO2-ERGNO presented fine globular nanostructure. However, ZrO2/ERGNO presented agglomerate massive microstructure due to the absence of the oxygen-containing groups of graphene oxide, confirming the oxygen-containing groups provided a better affinity for the deposition of ZrO2. Due to the strong binding of the phosphate groups of DNA with the zirconia film, DNA probes were attached on the ZrO2-based composites. ZrO2-ERGNO/Au owning fine nanostructure presented larger surface area than microstructured ZrO2/ERGNO/Au. Moreover, compared with microstructured ZrO2/ERGNO, the nanostructured ZrO2-ERGNO provided more accessible space for immobilized DNA probe hybridization with target sequence, which consequently resulted in higher hybridization efficiency. Therefore, the ZrO2-ERGNO was chosen for fabricating DNA sensor with a limit of detection 1.21×10(-14)molL(-1).
    Analytica chimica acta 07/2013; 786:29-33. · 4.31 Impact Factor
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    ABSTRACT: In this work, we prepared large-area, three-dimensional interconnected graphene oxide (GNO) intercalated by self-doped polyaniline nanofibers (SPAN, a copolymer of aniline and m-aminobenzenesulfonic acid) through a simple adsorption and intercalation route via sonication of the mixed dispersions of both components. The strong π–π* stacking between the backbones of SPAN and the GNO basal planes, and the electrostatic repulsion between the negatively charged SPAN and graphene oxide sheets yield a unique free-standing, three-dimensional interconnected nanostructure. The nanocomposite possesses a large specific surface area and maintains a homogenous and stable dispersion with SPAN, which endows it with a high conductivity and good electrocatalytic activity. Because the negative charge and specific structure of the nanocomposite can prompt the adsorption of positively charged guanine and adenine via strong π–π* interactions or electrostatic adsorption, the hybrid was adopted as an excellent sensing platform for highly sensitive determination of guanine and adenine. The electrocatalytic platform exhibited some advantages, such as high sensitivity, good reproducibility and long-term stability.
    J. Mater. Chem. B. 05/2013; 1(23):2926-2933.
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    ABSTRACT: A novel and simple synchronous electrochemical synthesis of poly(xanthurenic acid, Xa) -electrochemically reduced graphene oxide nanocomposite (PXa-ERGNO) via cyclic voltammetry (CV) was reported, where graphene oxide (GNO) and Xa monomer were adopted as precursors. The resulting PXa-ERGNO nanocomposite was characterized by scanning electron microscopy, Fourier Transform infrared spectroscopy, CV and electrochemical impedance spectroscopy (EIS). The π-π* interactions between the conjugated GNO layers and aromatic ring of Xa enhanced the electropolymerization efficiency accompanied with an increased electrochemical response of PXa. The rich carboxyl groups of PXa-ERGNO film were applied to stably immobilize the probe DNA with amino groups at 5' end via covalent bonding. The captured probe could sensitively and selectively recognize its target DNA via EIS. The dynamic detection range was from 1.0 × 10-14 mol/L to 1.0 × 10-8 mol/L with a detection limit of 4.2 × 10-15 mol/L due to the synergistic effect of integrated PXa-ERGNO nanocomposite. This graphene-based electrochemical platform showed intrinsic advantage, such as simplicity, good stability, and high sensitivity, which could serve as an ideal platform for the biosensing field.
    ACS Applied Materials & Interfaces 04/2013; · 5.01 Impact Factor
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    ABSTRACT: Herein, an electrochemical platform was employed for the detection of protein. Fe2O3 was electrochemically deposited on graphene modified glassy carbon electrode surface. Electrodeposition conditions, such as temperature, and time, were optimized for controlling morphologies and electrochemical activities of Fe2O3. Negatively charged lysozyme-binding aptamer (LBA) was immobilized on positively charged Fe2O3 (isoelectric point ∼7.0) via electrostatic interaction. Electrochemical impedance spectroscopy was adopted for indicator-free detection of lysozyme. The LBA on the outermost layer would catch lysozyme in solution by physical affinity, which induced the increase of impedimetric signals. In this strategy, a wide detection range (0.5ngmL(-1)-5μgmL(-1)) and low detection limit (0.16ngmL(-1)) for model target lysozyme was obtained. The results showed that indicator-free impedimetric aptasensing strategy had good sensitivity and selectivity.
    Talanta 02/2013; 105C:229-234. · 3.50 Impact Factor
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    ABSTRACT: A sensitive electrochemical impedimetric DNA biosensor based on the integration of tin oxide (SnO2) nanoparticles, chitosan (CHIT) and multi-walled carbon nanotubes (MWNTs) is presented in this paper. The MWNTs-SnO2-CHIT composite modified gold electrode was characterized by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). Compared with individual MWNTs-CHIT, SnO2-CHIT and bare gold electrode, this composite showed the most obvious electrochemical signal of the redox probe [Fe(CN)6](3-/4-). According to the change of the electron transfer resistance (Ret) induced by the hybridization, target DNA was successfully detected via EIS. This DNA electrochemical biosensor was applied to detect phosphinothricin acetyltransferase (PAT) gene in transgenic corn. The synergistic effect of the MWNTs-SnO2-CHIT remarkably enhanced DNA immobilization and hybridization detection. The dynamic detection range was from 1.0×10(-11)mol/L to 1.0×10(-6)mol/L with a detection limit of 2.5×10(-12)mol/L. This sensing platform showed inner advantage, such as simplicity, good stability, and high sensitivity.
    Colloids and surfaces B: Biointerfaces 01/2013; · 3.55 Impact Factor
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    ABSTRACT: In this paper, the poly-xanthurenic acid (PXa) was electropolymerized by cyclic voltammetry (CV) on a pre-obtained electrochemically reduced graphene oxide (ERGNO) film to construct a novel direct electrochemical DNA biosensor. Due to the unique properties of graphene, conjugated xanthurenic acid (Xa) monomers tended to be adsorbed on the graphene plane by π–π stacking and the electropolymerization efficiency was greatly improved, resulting in an enhanced electrochemical response of PXa. The PXa not only served as a substrate for DNA immobilization but also reflected the electrochemical transduction originating from DNA immobilization and hybridization without any outer indicators or complicated labeling. The capture probe was immobilized onto a modified electrode by covalent bonds between the amino groups of the capture probe and the carboxyl groups of the PXa/ERGNO film. The sensing platform could selectively recognize its target DNA. It is well-known that ssDNA is a flexible molecule while dsDNA acts as a rigid rod, which resulted in the change of the self-signals of the PXa after hybridization. The dynamic range of this DNA biosensor for detecting the sequence-specific DNA from promyelocytic leukemia was from 1.0 × 10−15 mol L−1 to 1.0 × 10−9 mol L−1 using electrochemical impedance spectroscopy, and the detection limit was 2.5 × 10−16 mol L−1.
    Polym. Chem. 01/2013; 4(4):1228-1234.
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    ABSTRACT: In very recent years, polyaniline or its derivatives have been adopted to efficiently immobilize probe DNA via π-π interaction between conjugated interface and DNA bases. In this work, self-doped polyaniline (SPAN)-DNA hybrid was adopted as the platform to construct a DNA biosensor with label-free, reagentless and electrochemical self-signal amplifying features. This was achieved by the π-π interaction between conjugated SPAN and DNA bases, also the intrinsic differences between single-stranded DNA (ssDNA) and double-stranded DNA (dsDNA). The tightly cross-linked hybrid was tethered to Au electrode, which had been anchored by p-aminothiophenol (PATP) self-assembled monolayer (SAM) previously, based on the phosphoramidate bond between PATP and ssDNA. SPAN in the recognition surface exhibited well-defined redox signals under neutral conditions. Due to the intrinsic property differences between ssDNA and dsDNA, such as rigidity, π-stacked bases, charge distribution and long-range electron transfer, SPAN-DNA underwent a major conformational change after hybridization. The redox behaviors of SPAN were modulated by DNA, which served as signals to monitor hybridization. As an example, the gene fragment related to one of the screening genes for the genetically modified plants, cauliflower mosaic virus 35S gene was satisfactorily detected with this strategy. Under optimal conditions, the dynamic range for the DNA assay was from 1.0 × 10(-14) mol L(-1) to 1.0 × 10(-8) mol L(-1) with the detection limit of 2.3 × 10(-15) mol L(-1). This work presents the construction of a recognition surface for the highly-sensitive electrochemical DNA hybridization detection via the self-signal amplifying procedure of conjugated SPAN-DNA hybrid. Unlike most signal amplifying processes using outer indicators, complex labels or other reagents, this procedure possesses simplicity and convenience.
    The Analyst 01/2013; · 4.23 Impact Factor
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    ABSTRACT: A novel one-step electrochemical synthesis of the reduced graphene oxide and poly(m-aminobenzenesulfonic acid, ABSA) nanocomposite (PABSA-rGNO) via pulse potentiostatic method (PPM) for direct and freely switchable detection of target genes is presented. Unlike the most of electrochemical preparation of hybrids based on rGNO and polymer, electrochemical synthesis of PABSA (during the pulse electropolymerization section of PPM) and electrochemical reduction of rGNO (during the resting section of PPM), in this paper, were alternately performed. The total progress synchronously resulted in PABSA-rGNO nanocomposite. This nanocomposite was characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray powder diffraction (XRD), Fourier Transform infrared spectroscopy (FTIR), cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The PABSA-rGNO nanocomposite integrated graphene (a single-atom thick, two-dimensional sheet of sp2 bonded conjugated carbon) with PABSA (owning rich-conjugated structures, functional groups, and excellent electrochemical activity), which could serve as an ideal electrode material for biosensing and electrochemical cell, etc. As an example, the immobilization of the specific probe DNA was successfully conducted via noncovalent method due to the π-π* interaction between conjugated nanocomposite and DNA bases. The hybridization between the probe DNA and target DNA induced the product dsDNA to be released from conjugated nanocomposite, accompanied with the self-signal regeneration of nanocomposite ("signal-on"). The self-signal changes served as a powerful tool for direct and freely switchable detection of different target genes and the synergistic effect of PABSA-rGNO nanocomposite effectively improved the sensitivity for the target DNA detection.
    Analytical Chemistry 12/2012; · 5.70 Impact Factor
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    ABSTRACT: An impedimetric and freely switchable DNA sensor based on electrochemically reduced graphene oxide (ERGNO) and polyaniline (PANI) film was presented, where ERGNO was prepared on PANI modified glassy carbon electrode (GCE). When the probe DNA was noncovalently assembled on the surface of electrode through π-π(⁎) stacking between the ring of nucleobases and the rich-conjugated structure of the nanocomposite, the electron transfer resistance value of [Fe(CN)(6)](3-/4-) increased. The negative ssDNA and the steric hindrance blocked the effective electron transfer channel of the [Fe(CN)(6)](3-/4-). After hybridization with the complementary DNA, the formation of helix induced dsDNA to release from the surface of conjugated nanocomposite, accompanied with the curtailment of the impedimetric value. The selectivity and sensitivity of this DNA sensing platform were characterized using electrochemical impedance spectroscopy in detail. The fabricated biosensor exhibited excellent performance for the detection of specific DNA sequence with a wide linear range (1.0×10(-15) to 1.0×10(-8)mol/L) and a low detection limit of 2.5×10(-16)mol/L due to the synergistic effect of ERGNO/PANI nanocomposites. The hosphinothricin acetyltransferase gene (PAT) was also detected to show the switchable ability of ERGNO/PANI.
    Biosensors & bioelectronics 11/2012; 42C:415-418. · 5.43 Impact Factor
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    ABSTRACT: In this paper, a simple and reliable fabrication method about electrochemically reduced graphene oxide (ERGNO)-prussian blue (PB) nanocomposite was proposed for determination of guanine. Due to its unique structural, physical and chemical properties, ERGNO, which was fabricated on the carbon paste electrode (CPE) beforehand through electrochemical reduction of graphene oxide, was selected as a compatible precursor for next-step PB electrodeposition. Electrochemical behaviors of the resulted PB/ERGNO/CPE were investigated by electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV) and differential pulse voltammetry (DPV). The electrochemical results showed that PB/ERGNO/CPE exhibited good electrochemical performances. The electrocatalytic results of guanine further illustrated that graphene prompted the electrocatalytic ability of PB via the redox shift between PB and prussian yellow (PY) in the potential range from 0.5 to 1.2 V, which has not been widely adopted in the PB based electrochemical sensors. The detection limit of guanine could be calculated to be 1.0×10−8 mol/L. It means this PB/ERGNO/CPE platform is quite sensitive and can be readily applied in biosensor field.
    Chinese Journal of Chemistry 09/2012; 30(9). · 0.92 Impact Factor
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    ABSTRACT: Fabrication of an electrochemical impedimetric DNA biosensor based on the integration of Au-Pt alloy nanoparticles (Au-Pt(NPs)) and electropolymerized polytyramine (Pty) film for the detection of phosphoenolpyruvate carboxylase (PEP) gene is described in this article, where Pty films acted as an ideal combination platform for Au-Pt(NPs) via electrostatic adsorption. The electrochemical properties of the Au-Pt(NPs)/Pty, the characteristics of the immobilization and hybridization of DNA were investigated by cyclic voltammetry, differential pulse voltammetry and electrochemical impedance spectroscopy (EIS), respectively. Primary study indicated that Au-Pt(NPs)/Pty had a synergistic effect on the electrochemical signal of [Fe(CN)(6)](3-/4-), which served as the classic redox probe in the most electrochemical impedimetric sensors. DNA sequence-specific of PEP transgene existed in some transgenic crops was detected by this EIS protocol. The dynamic detection range of this DNA electrochemical biosensor to the DNA target sequence was from 1.0×10(-12)M to 1.0×10(-7)M. The detection limit was measured to be 3.6×10(-13)M. The DNA biosensor also had good selectivity, stability and reproducibility.
    Colloids and surfaces B: Biointerfaces 04/2012; 97:150-4. · 3.55 Impact Factor
  • Wei Zhang, Xiuwen Zheng, Kui Jiao
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    ABSTRACT: A novel electrochemical impedance DNA biosensor for acute promyelocytic leukemia was developed by immobilizing a PML/RARA related 18-mer oligonucleotides ssDNA sequence on carbon ionic liquid electrode modified with nanosized ZnO. The morphology of ZnO nanoparticles was characterized by using scanning electron microscopy. Cyclic voltammetry and electrochemical impedance spectroscopy were performed for the study of decoration of ZnO, immobilization of ssDNA and the hybridization event at the electrode surface. Remarkable change has been observed in the impedance spectra before and after hybridization of probe ssDNA with the target DNA under optimal conditions. As a result, the effective probe immobilization platform, coupled with the ultrasensitive label-free impedance measurement, gave rise to a detection limit of 2.5 × 10−13 mol/L.
    Sensors and Actuators B: Chemical. 02/2012; 162(1):396–399.
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    ABSTRACT: A porous composite film was fabricated combining the advantages of multiwalled carbon nanotubes, CeO2 and chitosan. The synergistic effect of the film improved the immobilization of probe ssDNA. The loaded probe ssDNA was used for detection of CdSe quantum dots labeled target DNA. The DNA hybridization reaction was detected by differential pulse anodic stripping voltammetry of Cd2+ after the oxidative release of labeled CdSe quantum dots. The established DNA biosensor can discriminate different target sequences associated with 35S promoter of cauliflower mosaic virus gene with relatively wide linear range and low detection limit (2.4×10−13 mol/L).
    Electroanalysis 02/2012; 24(2). · 2.82 Impact Factor
  • Meng Du, Tao Yang, Xiao Li, Kui Jiao
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    ABSTRACT: A novel DNA electrochemical biosensor was described for the detection of specific gene sequences. Electrochemically reduced graphene oxide (ERGNO) was prepared on polyaniline (PAN) nanofibers modified glassy carbon electrode (GCE). Compared with the electrochemical reduction of graphene oxide directly on bare GCE (reduction potential: ca. -1.3V), more positive reduction potential (ca. -1V) for graphene oxide was observed with the PAN membrane existing. The formed ERGNO/PAN nanocomposites were applied to bind ssDNA probe via the non-covalent assembly. The surface density of ssDNA was calculated by voltammetric studies of redox cations ([Ru(NH(3))(6)](3+)), which were bound to the surface via electrostatic interaction with negative charged phosphate backbone of the DNA. After the hybridization of ssDNA probe with complementary DNA, the response of surface-bound [Ru(NH(3))(6)](3+) changed obviously, which could been adopted to recognize the DNA hybridization. Under optimal conditions, the dynamic range of the DNA biosensor for detecting the sequence-specific DNA of cauliflower mosaic virus (CaMV35S) gene was from 1.0×10(-13) to 1.0×10(-7)molL(-1), with a detection limit of 3.2×10(-14)molL(-1). This biosensor also showed a high degree of selectivity.
    Talanta 01/2012; 88:439-44. · 3.50 Impact Factor
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    ABSTRACT: A water-soluble chitosan-coordinated cadmium polymer was synthesized, and its recognition of single-stranded and double-stranded DNA was investigated. The electrochemical analysis in the homogeneous solutions revealed that the chitosan-coordinated cadmium polymer association with a single stranded DNA was 48 times greater than with double-stranded DNA due to the different interaction with the two kinds of DNA. The surface-based electrochemically absorbed chitosan-coordinated cadmium polymer molecules were easily removed from the double-stranded DNA-modified electrode via rinsing but could not be removed from a single-stranded DNA-modified electrode. Based on this fact, the polymer was utilized as a redox indicator for DNA hybridization detection, as the polymer was able to recognize complementary, noncomplementary, and base-mismatched sequences with a low background interference. The target DNA sequence was quantified from 5.0 × 10-9 to 5.0 × 10-7 M with a detection limit of 4.2 × 10-9 M. The polymerase chain reaction amplification of DNA from the real sample of a kind of transgenically modified soybeans was also detected satisfactorily.
    Journal of Bioactive and Compatible Polymers - J BIOACT COMPAT POLYM. 01/2012; 27(3):278-292.
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    ABSTRACT: AbstractA porous composite film was fabricated combining the advantages of multiwalled carbon nanotubes, CeO2 and chitosan. The synergistic effect of the film improved the immobilization of probe ssDNA. The loaded probe ssDNA was used for detection of CdSe quantum dots labeled target DNA. The DNA hybridization reaction was detected by differential pulse anodic stripping voltammetry of Cd2+ after the oxidative release of labeled CdSe quantum dots. The established DNA biosensor can discriminate different target sequences associated with 35S promoter of cauliflower mosaic virus gene with relatively wide linear range and low detection limit (2.4×10−13 mol/L).
    Electroanalysis 01/2012; 24(2). · 2.82 Impact Factor
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    ABSTRACT: An electrically neutral cobalt complex, Co(Eim)(4)(NCS)(2) (Eim=1-ethylimidazole, NCS=isothiocyanate) was synthesized and its interaction with double-stranded DNA (dsDNA) was comprehensively studied by electrochemical methods on a glassy carbon electrode (GCE). The experimental results revealed that the cobalt complex could interact with dsDNA via a specific groove-binding mode with an affinity constant of 3.6×10(5)M(-1). The surface-based studies showed that Co(Eim)(4)(NCS)(2) could electrochemically accumulate within the immobilized dsDNA layer rather than single-stranded DNA (ssDNA) layer. Based on this fact, the cobalt complex was utilized as an electrochemical hybridization indicator for the detection of oligonucleotides related to CaMV35S promoter gene. The results showed that the developed biosensor presented very low background interference due to the negligible affinity of the Co(Eim)(4)(NCS)(2) complex with ssDNA. The hybridization specificity experiments further indicated that the biosensor could well discriminate the complementary sequence from the base-mismatched and the non-complementary sequences. The complementary target sequence could be quantified over the range from 5.0×10(-9)M to 2.0×10(-6)M with a detection limit of 2.0×10(-10)M.
    Biosensors & bioelectronics 12/2011; 32(1):50-5. · 5.43 Impact Factor
  • Wei Zhang, Tao Yang, Kui Jiao
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    ABSTRACT: This paper describes a novel electrochemical DNA biosensor for simple, rapid, and specific detection of PML/RARA fusion gene in acute promyelocytic leukemia by using 18-mer single-stranded deoxyribonucleic acid as the capture probe. Nanosized Fe(2)O(3) was first immobilized on the surface of a carbon paste electrode (CPE). Then poly-xanthurenic acid (PXa), a new electroactive material, was electrogenerated by using the pulse potentiostatic method on the Fe(2)O(3) substrate to form a unique and uniform nanorhombus structure. Due to the unique binding ability of xanthurenic acid (Xa) with Fe(2)O(3), Xa monomers tended to be adsorbed around nanosized Fe(2)O(3), and the electropolymerization efficiency was greatly improved. Owing to the presence of abundant carboxyl groups, the capture probe was covalently attached on the carboxyl-terminated PXa/Fe(2)O(3) nanorhombus membranes through the free amines of DNA sequences based on the 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide and N-hydrosulfosuccinimide cross-linking reaction. The covalently immobilized capture probe could selectively hybridize with its target DNA to form double-stranded DNA on the PXa/Fe(2)O(3)/CPE surface. Electrochemical impedance spectroscopy was adopted for indicator-free monitoring of the hybridization reaction on the probe-captured electrode. As a result, the efficient probe immobilization platform, coupled with the ultrasensitive indicator-free impedance measurement, gave rise to a detection limit of 2.8 fmol/L and a dynamic range spanning 8 orders of magnitude. The excellent analytical properties of the proposed biosensor developed here holds great promise for ultrasensitive detection of other biorecognition events and diagnosis of diseases in practice.
    Biosensors & bioelectronics 10/2011; 31(1):182-9. · 5.43 Impact Factor

Publication Stats

936 Citations
388.49 Total Impact Points

Institutions

  • 2006–2013
    • Qingdao University of Science and Technology
      Tsingtao, Shandong Sheng, China
  • 2009–2011
    • Zhangzhou Normal University
      Lunki, Fujian, China
    • Qingdao University
      Tsingtao, Shandong Sheng, China
  • 2007–2008
    • Hunan University
      • State Key Laboratory of Chemo/Biosensing and Chemometrics
      Ch’ang-sha-shih, Hunan, China