Optimization of detection sensitivity in the capillary electrophoresis of inorganic anions

Determinação simultânea de ânions por eletroforese capilar: características e aplicações

“…19 A tabela 1 apresenta uma compilação de trabalhos, a partir de 1991, que utilizam a eletroforese capilar para determinação simultânea de ânions em matrizes de caráter ambiental, biológico e industrial.…”

“…A figura 1 ilustra este aspecto em particular, na separação de 36 ânions por eletroforese capilar e cromatografia iônica, mostrando de forma inequívoca o alto desempenho da coluna capilar. Os demais aspectos são: custo e durabilidade das colunas 16,17 , necessidade de tratamento prévio da amostra, tempo de análise 18 , volume de amostra 19 , e custo final por análise 20 . A conclusão que prevalece nestes estudos é que a eletroforese capilar apresenta inúmeras vantagens, o que tem contribuído para assegurar uma posição de destaque entre as técnicas analíticas de separação.…”

Optimization of the indirect fluorimetric detection for the simultaneous analysis of inorganic anions and polycharged organic anions by capillary electrophoresis

“…For instance OFM Anion -BT [16][17][18]32,35], cetyltrimethylammonium (CTAB) [21][22][23][24][25]36,37], hexamethonium [20,27,28,34] or trimethyltetradecylammonium (TTAB) [27,[29][30][31]33,[36][37][38] can be noted.…”

“…On the other hand, the indirect UV detection appears more attractive due to its universality. The chromophore commonly introduced into the electrolyte to generate the background signal is the chromate [12,[16][17][18]21,27,29,31,37]. However the utilization of dich ro m ate [11,30,34], p h t a l ate [7,14,20], py ro m e l l i t i c acid [20,26,27] or polysulfonated naphtalenes [8] can be also noted.…”

“…However the utilization of dich ro m ate [11,30,34], p h t a l ate [7,14,20], py ro m e l l i t i c acid [20,26,27] or polysulfonated naphtalenes [8] can be also noted. The introduction of these chromophores into the electrolyte often being matched by the addition of a quatern a ry ammonium surfa c t a n t , used as electroosmotic fl ow reverser, it is important to insure that incompatibility does not exist between these two components of the electrophoretic system, as is the case for the vanadium salts, that precipitate in front of some quaternary ammonium salts [16]. Otherwise the indirect fluorimetric detection, although less used, offers interesting potentialities concerning the sensitivity, for example in the case of the analyses of eleven priority phenols [45], of isopro p e ny l py ro p h o s p h ates [46], o f explosives [47] or of triorganotin compounds [48].…”