Simultaneous speciation analysis of chromium and antimony by novel carboxyl-functionalized hybrid monolithic column solid phase microextraction coupled with ICP-MS

In this work, a novel carboxyl-functionalized organicinorganic hybrid monolithic column (TMOS- co -CES) was prepared via one-pot co-condensation of carboxyethylsilanetriol sodium salt (CES) and tetramethoxysilane (TMOS). The TMOS- co -CES monolithic column was used as a needle-solid phase microextraction (SPME) matrix followed by using an inductively coupled plasma mass spectrometer (ICP-MS) for simultaneous speciation analysis of inorganic chromium and antimony. Various parameters of SPME operation and analytical performance were investigated systematically. Under the optimum conditions, the TMOS- co -CES column can selectively adsorb low-valent chromium (Cr( iii )) and antimony (Sb( iii )) without adsorbing high-valent species (Cr( vi ) and Sb( v )) over a wide pH range (4.09.0). In the elution step, the captured Cr( iii ) and Sb( iii ) can be substantially completely eluted using 10% nitric acid (v/v) as the eluent. The TMOS- co -CES monolithic column based SPME protocol has the merits of facile preparation, low cost, selective adsorption and high adsorption capacity. In addition, the TMOS- co -CES column operates under milder elution conditions, offers higher recovery for antimony species, and is more compatible with the ICP-MS instrument, compared with a previously reported thiol-functionalized hybrid monolithic column taking speciation analysis of antimony as an example. Therefore, the developed TMOS- co -CES monolithic column is more suitable than the thiol-functionalized monolithic column for the speciation analysis of chromium and antimony in environmental waters. Carboxyl hybrid monolithic columns were prepared from simple silane agents by one-pot for simultaneous speciation analysis of chromium and antimony.