Salt-assisted liquid-liquid extraction in microchannel.

Area of Science:

• Analytical Chemistry
• Separation Science
• Microfluidics

Background:

• Salt-assisted liquid-liquid extraction (SALLE) is a common technique for sample preparation.
• Traditional SALLE methods can be time-consuming and require large solvent volumes.
• Microfluidic systems offer advantages in reduced sample/solvent consumption and enhanced mass transfer.

Purpose of the Study:

• To develop and optimize a novel microchannel system for salt-assisted liquid-liquid extraction.
• To enhance the extraction efficiency of target analytes using increased surface area in microchannels.
• To apply the developed method for the determination of specific pharmaceutical compounds in biological matrices.

Main Methods:

• A microchannel system was designed to increase the contact surface area between sample and extracting phases.
• Salt, sample solution, and extracting solvent were mixed and introduced into the microchannel via a syringe pump.
• Key parameters including solvent type/volume, salt concentration, pH, and microchannel dimensions were optimized using zidovudine and tenofovir disoproxil fumarate as model analytes.

Main Results:

• The optimized microchannel SALLE method demonstrated excellent linearity (R² > 0.992) within the 0.1-30 µg/mL range.
• The proposed microchannel SALLE method exhibited significantly higher extraction efficiency compared to conventional SALLE.
• The method was successfully validated for the determination of zidovudine and tenofovir disoproxil fumarate in human plasma samples.

Conclusions:

• The developed microchannel salt-assisted liquid-liquid extraction system provides an efficient and effective approach for sample preparation.
• This novel microfluidic design enhances extraction performance and reduces analysis time.
• The method is suitable for the quantitative analysis of target analytes in complex biological samples like plasma.