Improved performance of wrinkled CoNi-LDHs via in situ immobilization onto cotton gauze for solid phase extraction of non-steroidal anti-inflammatory drugs

Layered Double Hydroxides as an Intercalation System for Hydrophobic Molecules

Layered double hydroxides (LDHs) have been extensively studied as drug delivery systems due to their favorable characteristics, including biocompatibility, high loading efficiency, and pH-responsive release. However, the current research predominantly focuses on LDHs as carriers for various anionic drugs, while there are only limited reports on LDHs as carriers for hydrophobic drugs. In this study, we successfully achieved the loading of a hydrophobic drug mimic, Nile red (NR), into LDHs using sodium dodecyl sulfate (SDS) as an intermediate storage medium. Furthermore, we optimized the experimental methods and varied the SDS/NR molar ratio to optimize this intercalation system. With an increase in the SDS/NR molar ratio from 2/1 to 32/1, the loading efficiency of LDH-SDS-NR for NR initially increased from 1.32% for LDH-SDS-NR_2/1 to 4.46% for LDH-SDS-NR_8/1. Then, the loading efficiency slightly decreased to 3.64% for LDH-SDS-NR_16.8/1, but then increased again to 6.31% for LDH-SDS-NR_32/1. We believe that the established method and the obtained results in this study broaden the application scope of LDHs as delivery systems for hydrophobic drugs and contribute to the further expansion of the application scope of LDHs.

Facile and efficient preparation of amino bearing metal-organic frameworks-coated cotton fibers for solid-phase extraction of non-steroidal anti-inflammatory drugs in human plasma

The determination of blood concentration of non-steroidal anti-inflammatory drugs (NSAIDs) is highly desired in clinical practice. In this work, three amino bearing metal-organic frameworks (amino-MOFs) coated cotton fibers were prepared using a facile cysteine-triggered in situ growth strategy and proposed as in-tip solid-phase microextraction (in-SPME) adsorbents for efficient extraction of non-steroidal anti-inflammatory drugs from human plasma. The self-made adsorbents exhibited satisfactory extraction performance toward three NSAIDs including diclofenac sodium, ketoprofen and flurbiprofen. Under the optimized conditions, the established method exhibited satisfactory enrichment performance, low limits of detection and excellent extraction efficiency. Good reproducibility, wide linear range, excellent linearity and satisfactory sensitivity were obtained in the experiment. The method was also used for the enrichment and determination of NSAIDs in human plasma samples. Good recoveries were obtained, ranging from 66.5% to 98.9% with relative standard deviations less than 6.62%. The good performance of amino-MOFs was due to the synergistic effects arising from grafted charged amino groups within ordered pores of suitable size, leading to strong affinity towards guest molecules. Electrostatic interaction, hydrogen bond and π-π interaction played a vital role in the extraction of NSAIDs. This report indicated the potential of amino-MOFs as efficient adsorbents for the determination of NSAIDs from human plasma.