Facile Fabrication of Diatomite-Supported ZIF-8 Composite for Solid-Phase Extraction of Benzodiazepines in Urine Samples Prior to High-Performance Liquid Chromatography

ZIF-8 as efficient carriers for polysaccharide from Tetrastigma Hemsleyanum Diels et Gilg in acute lung injury induced by lipopolysaccharides

Acute lung injury (ALI) is a critical respiratory syndrome significantly impacting patient health. Tetrastigma hemsleyanum Diels et Gilg (Sanyeqing, SYQ) is a traditional Chinese medicine and its polysaccharides (SYQP) have demonstrated efficacy in counteracting lipopolysaccharide-induced ALI. This study characterized the structure of SYQP and synthesized the SYQP@ZIF-8 composite using biomimetic mineralization, evaluating encapsulation and release efficiency. The biocompatibility of SYQP@ZIF-8 in vitro was assessed by the CCK-8 colorimetric assay and hemolytic activity. Inflammatory cytokine was measured to evaluate the therapeutic effect. The efficacy of SYQP@ZIF-8 in lung injury was assessed using a mice ALI model. Characterization showed SYQP as a homogeneous α-type polysaccharide, comprising galactose, mannose, glucuronide, glucose, galacturonide, and arabinose, with a molecular weight of 516.94 kDa. SYQP@ZIF-8 exhibited high encapsulation rate (> 90 %), rapid pH-responsive release (within 60 min up to ~100 %), low toxicity and favorable hemolytic characteristics. Furthermore, it demonstrated reduced inflammatory cytokine secretion compared to SYQP, along with a superior inhibitory effect. The outcomes of in vivo experiments, including a decrease in the W/D ratio and LDH activity, further confirmed the efficacy of SYQP@ZIF-8 in treating LPS-induced ALI. In conclusion, SYQP@ZIF-8 released SYQP in acidic inflammatory conditions, outperforming SYQP alone in treating ALI.

Thymosin beta 10 loaded ZIF-8/sericin hydrogel promoting angiogenesis and osteogenesis for bone regeneration

Angiogenesis is pivotal for osteogenesis during bone regeneration. A hydrogel that promotes both angiogenesis and osteogenesis is essential in bone tissue engineering. However, creating scaffolds with the ideal balance of biodegradability, osteogenic, and angiogenic properties poses a challenge. Thymosin beta 10 (TMSB10), known for its dual role in angiogenesis and osteogenesis differentiation, faces limitations due to protein activity preservation. To tackle this issue, ZIF-8 was engineered as a carrier for TMSB10 (TMSB10@ZIF-8), and subsequently integrated into the self-assembled sericin hydrogel. The efficacy of the composite hydrogel in bone repair was assessed using a rat cranial defect model. Characterization of the nanocomposites confirmed the successful synthesis of TMSB10@ZIF-8, with a TMSB10 encapsulation efficiency of 88.21 %. The sustained release of TMSB10 from TMSB10@ZIF-8 has significantly enhanced tube formation in human umbilical vein endothelial cells (HUVECs) in vitro and promoted angiogenesis in the chicken chorioallantoic membrane (CAM) model in vivo. It has markedly improved the osteogenic differentiation ability of MC 3 T3-E1 cells in vitro. 8 weeks post-implantation, the TMSB10@ZIF-8/ Sericin hydrogel group exhibited significant bone healing (86.77 ± 8.91 %), outperforming controls. Thus, the TMSB10@ZIF-8/Sericin hydrogel, leveraging ZIF-8 for TMSB10 delivery, emerges as a promising bone regeneration scaffold with substantial clinical application potential.

Degradation Kinetic Studies of BSA@ZIF-8 Nanoparticles with Various Zinc Precursors, Metal-to-Ligand Ratios, and pH Conditions

Nanosized zeolitic imidazolate framework particles (ZIF-8 nanoparticles [NPs]) have strong potential as effective carriers for both in vivo and in vitro protein drug delivery. Synthesis of ZIF-8 and stability of protein encapsulation within ZIF-8 are affected by several factors, notably the metal ion source and molar ratio. To systematically investigate these factors, we investigated such effects using BSA as a model test protein to synthesize BSA@ZIF-8 NPs at various metal-to-ligand (M:L) ratios. SEM, FTIR, XRD, and DLS were applied to characterize the morphology and structure of BSA@ZIF-8 NPs and their effects on protein loading capacity. Degradation kinetics and protein release behavior of BSA@ZIF-8 NPs were evaluated at pH 5.0 (to simulate the tumor environment) and pH 7.4 (to mimic the blood environment). Our objective was to define optimal combinations of the high protein loading rate and rapid release under varying pH conditions, and we found that (i) the yield of BSA@ZIF-8 NPs decreased as the M:L ratio increased, but the protein content increased. This highlights the need to strike a balance between cost-effectiveness and practicality when selecting ZIF-8 NPs with different molar ratios for protein-based drug formulation. (ii) BSA@ZIF-8 NPs exhibited cruciate flower-like shapes when synthesized using Zn(NO3)2 as the zinc precursor at M:L ratios of 1:16 or 1:20. In all other cases, the NPs displayed a regular rhombic dodecahedral structure. Notably, the release behavior of the NPs did not differ significantly between these morphologies. (iii) When Zn(OAc)2 was used as the zinc precursor, the synthesized ZIF-8 NPs exhibited a smaller size compared to the Zn(NO3)2-derived ZIF-8 NPs. (iv) The release rate and amount of BSA protein were higher at pH 5.0 compared to pH 7.4. (v) Among the different formulations, BSA@ZIF-8 with an M:L ratio of 1:16 at pH 5.0 was observed to have a shorter time to reach a plateau (0.5 h) and higher protein release, making it suitable for locally rapid administration in a tumor environment. BSA@ZIF-8 prepared from Zn(OAc)2 at an M:L ratio of 1:140 showed the slower release of BSA protein over a 24-h period, indicating its suitability for sustained release delivery. In conclusion, our findings provide a useful basis for the practical application of ZIF-8 NPs in protein-based drug delivery systems.

Benzodiazepines in complex biological matrices: Recent updates on pretreatment and detection methods

Benzodiazepines (BDZs) are used in clinics for anxiolysis, anticonvulsants, sedative hypnosis, and muscle relaxation. They have high consumptions worldwide because of their easy availability and potential addiction. They are often used for suicide or criminal practices such as abduction and drug-facilitated sexual assault. The pharmacological effects of using small doses of BDZs and their detections from complex biological matrices are challenging. Efficient pretreatment methods followed by accurate and sensitive detections are necessary. Herein, pretreatment methods for the extraction, enrichment, and preconcentration of BDZs as well as the strategies for their screening, identification, and quantitation developed in the past five years have been reviewed. Moreover, recent advances in various methods are summarized. Characteristics and advantages of each method are encompassed. Future directions of the pretreatment and detection methods for BDZs are also reviewed.