| Since the chemical and biological properties of the elements are directly linked to their chemical forms, element speciation has gained growing awareness in scientific research in past decades. Three projects were carried out in this thesis research work, developing methods to analyze element species in body fluids by using diverse separation techniques along with ICP-MS detection.; In the first project, in order to study the metabolism of inorganic arsenic in human body, a sensitive and robust method for the determination of seven inorganic and organic arsenic species in urine was developed using ion exchange chromatography combined with inductively coupled plasma mass spectrometry (IC-ICP-MS). Both anion and cation exchange columns were used in a complementary fashion. Arsenite (As(III)), arsenate (As(V)), monomethylarsonic acid (MMA(V)) and dimethylarsinic acid (DMA(V)) were selectively separated by an anion exchange column, while monomethylarsonous acid (MMA(III)), dimethylarsinous acid (DMA(III)) and arsenobetaine (AsB) were separated by a cation exchange column. Baseline separation, high repeatability and low detection limits (0.10-0.75 ng mL -1) were achieved.; Because only the toxic arsenic species in urine originate from inorganic arsenic exposure, in the second project, hydride generation inductively coupled plasma mass spectrometry (HG-ICP-MS), a simple and fast method, was developed to directly determine the total concentration of toxic arsenic species in the urine samples. Under optimized condition with 1% NaBH4, 0.2 M HCl and 0.05 M Cysteine, the toxic arsenic species were effectively separated from non-toxic species and they had similar sensitivity with HG-ICP-MS detection. With this method, good linearity, repeatability and recovery were achieved along with the low detection limit of 6 ppt (3sigma).; Carboplatin is a major platinum (Pt) based anti-cancer drug. The interactions between carboplatin and blood plasma proteins may affect the activity of carboplatin. In the third project, to study the carboplatin-protein interaction, a sensitive method using size exclusion chromatography coupled to inductively coupled plasma mass spectrometry (SEC-ICP-MS) was developed. Using this method, composite blood plasma samples from patients who were undergoing chemotherapy were analyzed, and carboplatin was found to bind plasma proteins. In addition, blank plasma samples were spiked with carboplatin and were analyzed as a time course study, and the results confirmed that carboplatin can form complexes with plasma proteins. To further substantiate the study, two major proteins in blood plasma, albumin and gamma-globulin, were incubated with carboplatin. The binding between carboplatin and those proteins were characterized using this method and the kinetics of the binding process was studied. |
