Development of a capillary electrophoresis analysis method with laser-induced fluorescence detection (LIF) and metallated sulphonated phthalocyanine mass spectrometry

Author(s)

Marcia Rodrigues dos Santos

• Document type: Doctoral Thesis
• Press: São Paulo.
• Institution: Universidade de São Paulo (USP). Conjunto das Químicas (IQ e FCF) (CQ/DBDCQ)
• Defense date: 2000-06-06

Examining board members

Joel Camargo Rubim; Mauricio da Silva Baptista; Emanuel Carrilho; João Batista Fernandes; Claudimir Lucio do Lago

• Advisor: Joel Camargo Rubim; Marina Franco Maggi Tavares

Abstract

In this work, the synthesis, purification and analysis of sulphonated metallo-phthalocyanines, used as therapeutical drugs in the therapy of cancer, were proposed. The analysis was conducted by capillary electrophoresis with laser-induced fluorescence detection as well as mass spectrometry. The first chapter discusses the implementation of a capillary electrophoresis system coupled to a Raman spectrometer, comprising a CCD detector, which was actually used as a fluorescence detector. An electronic device was also built to allow electrokinetic injections. Besides the characterization of the homemade system, it is also detailed in this chapter, the effect of the CCD binning on the detection limit of the Zn-tetrasulfonated phthalocyanine, which is in the order of 10-11 mol L-1. Chapter 2 focuses on the synthesis and purification strategies for the Zn-disulfonated phthalocyanine, monitored by capillary electrophoresis. Among the contaminants, inorganic cations and anions were screened as well as organic species in the final product, by using different wavelengths and discrete electrolytes. This study showed that purification procedures known in the literature as salting-out, acid-base wash, Soxhlet extraction and percolation through silica gel column, when used as a single procedure, are not sufficient to purify the synthetic product. Several combinations of two procedures were attempted and the best results were obtained when the acid-base wash followed by a percolation in silica gel column was employed. In Chapter 3, several electrolyte systems for the capillary electrophoresis and mass spectrometry analysis of zinc, luthecium and dysprosium di- and tetra-sulfonated phthalocyanines were evaluated. An interesting correlation between the mass spectrometry results and the species in the electropherogram was done for citrate and CAPS buffer, in neutral, basic and acidic media. Moreover, the addition of SDS in the citrate buffer, in the concentration range of 3 to 150 mmol.L-1, revealed an interesting interaction between the phhthalocyanine, charged to different degrees, and the micelle. SDS micelles occur in the citrate buffer in a concentration above 7 mmol.L-1 SDS. This interaction was discussed in terms of retention factor, k\' and partition coefficient, K. (AU)