Metal-Organic Frameworks in Bioanalysis: Extraction of Small Organic Molecules

Abstract

The quantitative determination of xenobiotic compounds, as well as biotics in biological matrices, is generally described with the term bioanalysis. Due to the complexity of biofluids, in combination with the low concentration of the small molecules, their determination in biological matrices is a challenging procedure. Apart from the conventional solid-phase extraction, liquid-liquid extraction, protein precipitation, and direct injection approaches, nowadays, a plethora of microextraction and miniaturized extraction techniques have been reported. Furthermore, the development and evaluation of novel extraction adsorbents for sample preparation has become a popular research field. Metal-organic frameworks (MOFs) are novel materials composed of metal ions or clusters in coordination with organic linkers. Unequivocally, MOFs are gaining more and more attention in analytical chemistry due to their superior properties, including high surface area and tunability of pore size and functionality. This review discusses the utilization of MOFs in the sample preparation of biological samples for the green extraction of small organic molecules. Their common preparation and characterization strategies are discussed, while emphasis is given to their applications for green sample preparation.

Metal–organic frameworks in chiral separation of pharmaceuticals

“…After the adsorption of the target analyte on the sorbent, the external magnetic field is applied to separate the magnetic adsorbent from the sample solution. Subsequently, a target analyte is desorbed using appropriate eluent and analyzed by suitable instrumental techniques 154–157 . Common problems associated with column blocking, sorbent filling, high back pressure, and packet bed plugging in conventional SPE can be avoided using MSPE 158,159 .…”

“…After the process, the analyte remains in a cleaner liquid phase 166 . It is a simple and rapid sample preparation technique that avoids potential limitations of the conventional SPE process, such as channeling or blocking cartridges 154 . Anastassiades et al used DSPE to estimate the residual pesticide content in fruits and vegetables 167 .…”

Effect of Geometrical Parameters on Extraction Efficiency of the Annular Centrifugal Contactor

“…Therefore, the mixing time became longer, and the extractant extracted more components, which improved mass transfer performance. (2) The ALH decreased when the annular width increased, leading to unit volume power (P/V) reduction. Thus, the mass transfer coefficient decreased, which was detrimental to mass transfer.…”

“…This technique is conducted according to the different solubility of the components in the solvent and the extractant. Mixer-settlers, pulse extraction columns, and annular centrifugal contactors (ACCs) are common instruments used in liquid-liquid extraction [1,2]. The first two types of equipment utilize gravity for separation and result in a slow separation of the light phase from the heavy phase, while an ACC is an efficient device that utilizes centrifugal force.…”

Bar Adsorbent Microextraction with Carbon-Based Sorbent Layers for the Identification of Pharmaceutic Substances

“…In contrast to HPLC, LC-MS can be utilized in the analysis of mixtures that are only partially resolved. Exhaustive conventional pretreatment procedures such as liquid-liquid extraction (LLE) and solid-phase extraction (SPE) are being utilized to separate and preconcentrate diverse families of analytes from aquatic and terrestrial ecosystems [13]. Due to the necessity to reduce solution quantities and avoid utilizing harmful organic solvents throughout LLE and SPE, existing preconcentration techniques have been modified to develop innovative methodologies.…”