Turbulent flow chromatography in bioanalysis: a review

Abstract

With advances in fast chromatography techniques, and highly sensitive and selective detection methods such as tandem mass spectrometry, very high-throughput bioanalytical methods can now be easily developed. The bottleneck of the analytical process then becomes the sample preparation, which it is now realized is crucial to the robust operation of the analytical system, especially for quantitative assays. Turbulent flow liquid chromatography was developed in the late 1990s, and combines 'size exclusion' and traditional stationary phase column chemistry to separate macromolecules, such as proteins, from smaller molecules and analytes of interest in biological fluids. By definition, the process is very rapid, and the instrumentation and software have been developed for fully automated, on-line extraction of neat biological fluids. This work aims to review the chromatographic theory of turbulent flow chromatography and illustrate, using examples from recent literature, the application of this technique to a range of analytes from a number of different biological matrices.

Automated and sensitive determination of four anabolic androgenic steroids in urine by online turbulent flow solid-phase extraction coupled with liquid chromatography–tandem mass spectrometry: A novel approach for clinical monitoring and doping control

“…The major characteristic is the large particles (60 μm) of solid phase in column, which make them separate large matrix components from smaller molecules efficiently when the fluid in the column is turbulent. Therefore, endogenous macromolecules such as proteins as well as nonvolatile substances in urine may be excluded and have no time to diffuse into the pores of particles and generate physical and chemical reaction at a certain sample loading flow rate [31,32]. Smaller molecules both polar and nonpolar ones were absorbed into particles theoretically.…”

Electrospray Ionization Mass Spectrometry for the Quantification of Inorganic Cations and Anions

“…To minimize matrix effects, various approaches, including on-line or off-line sample separation using chromatographic techniques, [20][21][22][23][24] liquid-liquid extraction, 21 and use of nanospray 25 have been described and reviewed. [26][27][28] Evaluations based on the relative signal intensities using internal standards, which are typically stable isotope-labeled analogues or compounds having similar structures to the analytes, are also effective in diminishing the matrix effect, 20,22,23 but this may not always be applicable. 29 Nevertheless, the matrix effect is strongly dependent on the chemical nature of each sample, so there is no universal approach that minimizes or overcomes the matrix effect.…”

Direct analysis of eight chlorophenols in urine by large volume injection online turbulent flow solid-phase extraction liquid chromatography with multiple wavelength ultraviolet detection

“…Macromolecules such as proteins may be excluded from the Turboflow column, and have no time to diffuse into the pores of particles and interact with stationary phase chemistry at a relatively high flow rate [31,37], which was optimized (Section 3.3).…”

“…The online Turboflow column is a kind of novel columns for online preconcentration, which is very effective for direct and fast analyzing complicated biological fluids, such as urine, serum and saliva [31][32][33]. Currently, this technique is mainly used for analysis of drugs and biomarkers.…”