Zhong J.-H.,Longyan Entry Exit Inspection and Quarantine Bureau |
Zhong J.-H.,State Key Testing Laboratory of Mineral |
Zhong J.-H.,Fuzhou University |
Guo L.-Q.,Fuzhou University |
And 6 more authors.
Guang Pu Xue Yu Guang Pu Fen Xi/Spectroscopy and Spectral Analysis | Year: 2012
A fast, sensitive, colorimetric method for the detection of pH based on the differentiate effect of gold nanoparticles to the configuration of DNA was developed in this study. The UV-Vis absorption spectroscopy of the i-motif DNA-Au NPs system has been investigated, and the effect of the concentration of salt and i-motif DNA, reaction time and DNA sequence on the pH response of the system have been also optimized. Under the optimum conditions, the UV-Vis absorption spectroscopy of the Au NPs is changed regularly with pH in the range of 5.3~7.0, the absorbance at 520 nm is increased gradually while at 700 nm decreased. Correspondingly, the color of the Au NPs is varied from violet to red. The pH sensor is no need to modification, low cost, fast and can be carried out by naked eyes. It is promising to use in monitoring some life process which associated with pH variation. Source
Chen J.-F.,Longyan Entry Exit Inspection and Quarantine Bureau |
Chen J.-F.,State Key Testing Laboratory of Mineral |
Huang H.-B.,Longyan Entry Exit Inspection and Quarantine Bureau |
Huang H.-B.,State Key Testing Laboratory of Mineral |
And 5 more authors.
Yejin Fenxi/Metallurgical Analysis | Year: 2011
A simultaneous determination method of arsenic, copper, manganese, molybdenum, phosphorus and silicon in ferrotungsten by inductively coupled plasma-atomic emission spectrometry was established. The samples were dissolved with oxalic acid and hydrogen peroxide. The matrix elements (W and Fe) and other coexisting elements had no interference with the testing elements. Under the optimal conditions, the detection limits of arsenic, copper, manganese, molybdenum, phosphorus and silicon were 0.009, 0.006, 0.0001, 0.0003, 0.005 and 0.002 μg/mL, respectively. The standard addition recoveries were 95%-108%, and the relative standard deviation (RSD, n = 3) was 0.1%-3.3%. The proposed method has been applied to the determination of certified reference material, the results were in good agreement with the certified values. Source