A new, rapid and highly sensitive and rapid method was proposed for the simultaneous determination trace levels of vitamin C and folic acid in the human urine samples. The inûuence affecting factors on the UA-DLLME such as type and volume of the dispersive and extraction solvent, pH, ionic strength and temperature of sample solution, sonication condition investigated and optimized. Under the op...

This paper would like to compare two extraction procedures for analyzing phthalates (PAEs) in hot drinks collected at vending machines, usually coffee and tea. The analytical are based on Solid Phase Extraction (SPE) using C18 cartridge dispersive liquid-liquid microextraction (DLLME) assisted by ultrasound vortex improving the dispersion mechanically, with each followed a routinary method such...

Until recently, sample preparation was carried out using traditional techniques, such as liquid-liquid extraction (LLE), that use large volumes of organic solvents. Solid-phase extraction (SPE) uses much less solvent than LLE, although the volume can still be significant. These preparation methods are expensive, time-consuming and environmentally unfriendly. Recently, a great effort has been ma...