| It is a well-known fact that the toxicity, bioavailability, and transport properties of an element are not only dependent upon its total quantification, but also highly lie on the chemical species. The different element speciation have different chemical and biological action. To completely understand the ways in which particular elements will affect living organisms, it is necessary to determine the species within which the elements are found, and to quantify those species. Analysis performed to identify or quantify one or more distinct chemical species in a sample is known as speciation analysis.The capillary electrophoresis (CE) was developed rapidly in the eighties of the 20th century as a novel separation and analysis technology. It is considered to be one of the strongest influence branches of analysis field at the end of last century, as well as the frontier of this field. It has many advantages: high efficiency, quick analysis speed, many analysis modes, little reagent consumption, wide application, easy automation, etc. Thus it shows extremely important application to life sciences, biotechnology, clinical medicine, medicine analysis and environmental science and so on.Inductively coupled plasma atomic emission spectrometry (ICP-AES) offers extending good advantages in terms of low detection limit, high precision, wide linear range and simultaneous multi-elements determination, widely used in trace-element analysis fields in recent years. CE coupled with ICP-AES has the individual advantages of capillary electrophoresis and inductively coupled plasma spectrometry, it realized the combination of efficient separation and element alternative measurement. It was considered as a powerful analytical method.Ultrasonic is a mechanical wave which the frequency is between 20 kHz～106 kHz, is not only a wave, but also an energy. Before analysizing complex system with CE, the samples must be purified. In this paper, an ultrasonic dialysis device has been set up, which had a good efficiency in blood speciation analysis. Studying on the speciation of complex systems by ultrasonic dialysis-CE-ICP-AES, which provided a more important information in the field of biological science, environmental science, clinic medicine and nutrition.In this paper, the research has been carried on foundation of ultrasonic dialysis capillary electrophoresis and inductively coupling plasma atomic emission spectrometry and their application to the speciation analysis of complex systems, such as biological samples (blood, plasma). The main contents were described as follows:1. A new method for the determination of free calcium concentration in human plasma was developed by on-line coupling capillary electrophoresis (CE) with inductively coupled plasma optical emission spectrometry (ICP-OES). Baseline separation of calcium-containing species was achieved by CE-ICP-OES in a 120 cm long capillary with 100μm internal diameter, at 20 kV applied voltage, with a 30 mmol/L Tris-HCl buffer at pH 7.4. A total of eight calcium-containing species were found in human plasma; the concentration of free calcium ion was found to be 41.9 mg/L. The precision (RSD, n = 10) ranged from 1.2 to 2.7% for the migration time and 2.8 to 3.9% for the peak area. The developed method was also applied to analyze plasma samples with recovery ranged from 94.5 to 102% for samples spiked with 40.0 mg/L free calcium ion.2. A new purification method for biological samples- ultrasonic dialysis technique has been developed. The feasibility of this method and its application were tested. The analytical performances have been studied, such as power , time, frequency, etc. The experimental result showed that optimal conditions were power of 72 W,frequency of 59 kHz,time of 60 min. The application of the developed ultrasonic dialysis -CE-ICP-OES for the speciation analysis of Zn2+, ZnEDTA2-, Cu2+and CuEDTA2- was highlighted. The detection limits of these elements were lower than 80μg·L-1, RSDs for those lower than 5%. This device was also used to calcium speciation in the blood dialysate, the result showed five calcium-containing species. The hyphenated technique was simple and convenient, which was fit for the separation and analysis of biological samples.3. The analytical method for speciation analysis of calcium in human whole blood was first studied, there had 10 species in human whole blood. The concentration of free calcium ion was 44.3 mg·L-1. Five spicies were identified using ultrasonic-assisted dialysis coupled with inductively coupled plasma optical emission spectrometry in the dialysate of the blood, which molecular weight≤15000. The developed method was also applied to analyze samples with recovery was 96.9% for sample spiked with 5.0 mg/L free calcium ion. The precision (RSD, n = 10) ranged from1.5 to5.1% for for the peak area. The detection limit for free calcium was 0.027 mg/L(3σ). |
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