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ABSTRACT: In this paper, we reported a convenient fluorescence method for the detection of genetically modified organisms (GMOs). As it is known that the cauliflower mosaic virus (CaMV) 35S promoter is widely used in most transgenic plants (Schnurr and Guerra, 2000), we thus design a simple method based on the detection of a section target DNA (DNA-T) from the transgene CaMV 35S promoter. In this method, the full-length guanine-rich single-strand sequences were split into fragments (Probe 1 and 2) and each part of the fragment possesses two GGG repeats. In the presence of K(+) ion and berberine, if a complementary target DNA of the CaMV 35S promoter was introduced to hybridize with Probe 1 and 2, a G-quadruplex-berberine complex was thus formed and generated a strong fluorescence signal. The generation of fluorescence signal indicates the presence of CaMV 35S promoter. This method is able to identify and quantify Genetically Modified Organisms (GMOs), and it shows wide linear ranges from 5.0×10(-9) to 9.0×10(-7)mol/L with a detection limit of 2.0×10(-9)mol/L.
Biosensors & bioelectronics 08/2012; · 5.43 Impact Factor
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ABSTRACT: A novel fluorescent sensor for detection of genetically modified organisms was developed, and in the sensor G-quadruplex DNAzyme (G-quadruplex-hemin complex) was used as the turn on switch.
Chemical Communications 02/2011; 47(5):1437-9. · 6.17 Impact Factor
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ABSTRACT: A capillary electrophoresis (CE) method coupled with electrochemiluminescence (ECL) detection for the analysis of glyphosate (GLY) and its major metabolite aminomethylphosphonic acid (AMPA) is presented. Complete separation of GLY and AMPA was achieved in 8 min using a background electrolyte of 20 mM sodium phosphate (pH 9.0) and a separation voltage of 21 kV. ECL detection was performed with an indium tin oxide (ITO) working electrode bias at 1.6 V (vs. a Pt-wire reference) in a 30 0mM sodium phosphate buffer (pH 8.0) containing 3.5mM Ru(bpy)3 2+ (where bpy=2.2'-bipyridyl). Linear correlation (r>or=0.997) between ECL intensity and analyte concentration was obtained in the ranges 0.169-16.9 and 5.55-111 microg ml(-1) for GLY and AMPA, respectively. The limits of detection (LODs) for GLY and AMPA in water were 0.06 microg ml(-1) and 4.04 microg ml(-1), respectively. The developed method was applied to the analysis of GLY in soybeans. The LOD of GLY in soybean was 0.6 microg g(-1). Total analysis time including sample pretreatment was less than 1h.
Journal of Chromatography 01/2008; 1177(1):195-8. · 4.53 Impact Factor
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ABSTRACT: The present paper reports the establishment of an electrochemi-luminescence (ECL) sensor by using screen-printed electrodes(SPE) which contain Ru(bpy)3(2+). The method of making the SPE and the fix of Ru(bpy)3(2+) were studiedin detail. The characters of the sensor were studied. The sensor has been applied to detect C2O4(2-) in solution. Under optimised conditions, at 1.55 V vs. Ag/AgCl, in 0.2 mol x L(-1) phosphate buffer solution (pH 6.0), the linger range extends from 3.0 x 10(-7) mol x L(-1) to 1.0 x 10(-5) mol x L(-1), the detection limit is 1.2 x 10(-7) mol x L(-1) (S/N=3). The sensors have good stability and reproductivity. It should be noted that based on the same principle, the sensors can be applied to detect many other compounds, such as amino acids, TprA and NAD. If the screen machine is used to make the SPE, the reproductivity and stability of the SPEs can be improved further.
Guang pu xue yu guang pu fen xi = Guang pu 12/2006; 26(11):1996-9. · 0.84 Impact Factor
