1.Application of Fourier Transform in Current Separation of Fast Scanning Voltammetry
Zonghai CHEN ; Xiangqin LIN ; Xueguang SHAO ; Zhaoxiang DENG
Chinese Journal of Analytical Chemistry 2001;29(6):625-628
A mathematical model of electro-chemical cell was induced according to its electric model. Based on the mathematical model, Fourier transform (FT) was applied to separate the charging current from Faradaic current in fast scanning voltammetric signal. The proposed method was investigated with both simulated voltammogram and experimental voltammogram. The results indicate that the proposed methods can successfully separate the charging current from Fradaic current, and the result is consistent with theoretical model.
2.Flow Injection Analysis of Tannic Acid withEnhanced Chemiluminescent Detection
Shifeng LI ; Hua CUI ; Yugang SUN ; Xiangqin LIN
Chinese Journal of Analytical Chemistry 2001;29(3):333-335
A novel flow injection chemiluminescent enhancement method for the determination of tannic acid based on luminol-KIO4-Mn2+ system is developed. The method is simple, rapid and effective to determine tannic acid in the range of 3.0×10-8~5.0×10-6 mol/L with a detection limit of 9×10-9 mol/L. The relative standard deviation is 1.5% for the determination of 1.0×10-6 mol/L tannic acid (n=11). The mehtod has been applied to determine the content of tannic acid in Chinese gall with satisfactory results.
3.Clinical, laboratory, and neuroimaging characteristics of neuroacanthocytosis
Xiangqin ZHOU ; Hongzhi GUAN ; Xiangsong SHI ; Liying CUI ; Lin CHEN ; Yehua HAN ; Haitao REN
Chinese Journal of Neurology 2012;45(2):112-115
Objective To investigate the clinical,laboratory,and neuroimaging characteristics of neuroacanthocytosis.Methods Eight patients with neuroacanthocytosis were retrospectively analysed.Acanthocytes were tested by peripheral blood smear,wet preparation with saline dilution,and scanning electron microscope.Results Two male and 6 female patients were included.The age at onset was between 10 and 35 years,with a mean age at onset of 22 years.Four patients firstly presented with oral-facial-lingual dystonia,3 patients firstly presented with involuntary movements of the distal limbs and experienced the oral facial dystonia during the course of disease,and 1 patient primary presented with a parkinsonian syndrome.Four patients had generalized tonic-clonic seizures were reported in 4 patients,and 4 patients had cognitive impairment.Hypotonia and hyporeflexia were reported in 6 patients.The peripheral blood smear revealed the presence of acanthocytes in 7 patients,in addition,wet preparation with saline dilution and scanning electron microscope revealed the presence of acanthocytes in the remaining one.All patients showed slightly elevated serum creatine kinase.Brain magnetic resonance imaging (MRI) showed variable atrophy of the bilateral caudate nuclei and putamen,with or without a rim of increased T2-intensity in 6 patients,but the films of 2 patients were read as normal.Electromyography and nerve conduction velocity were examined in 4 patients.The results indicated axonal damage in 2 patients,and were normal in the other 2 patients.Acanthocytosis was confirmed by peripheral blood smear in 7 cases,by wet preparation with saline dilution in 8 cases and by scanning electron microscope in 2 cases.Conclusions Neuroacanthocytosis is a progress neurodegenerative disorder mainly affected the basal ganglia. The clinical characteristics include oral facial dystonia,limbs chorea,cognitive impairment,and seizures. Brain MRI showed variable atrophy of the bilateral caudate nuclei and putamen.The peripheral blood smear,wet preparation with saline dilution,and scanning electron microscope methods of peripheral blood examination are critical in the diagnosis of neuroacanthocytosis.
4.Application of Portable Electrokinetic Flow Analysis System for Determination of Chromium (Ⅵ) and Cadmium (Ⅱ) in Mineral Water
Yang Li ; He Youzhao ; Gan Wu er ; Deng Ning ; Li Min ; Lin Xiangqin
Chinese Journal of Analytical Chemistry 2001;29(5):555-557
The improvement of the electroosmotic pump properties and the effects of the bi-directional electrostacking system on the pre-concentration factor were investigated.A portable electrokinetic flow analysis system with electroosmotic driving and bi-directional electrostacking unit was introduced.The improved system with graphite furnace atomic absorption spectrometry was employed to separate,pre-concentrate and determine Cr(Ⅵ) and Cd(Ⅱ)in mineral water.The detection limit of Cr(Ⅵ)and Cd(Ⅱ)was 9 ng/L and 10 ng/L(3б of blank,n=11),respectively.Their recoveries of 200ng/L Cr(Ⅵ) and 100ng/L Cd(Ⅱ) added to samples were(105~107)±2% and (104~106)±2%(n=3).