Fabrication of dopamine conjugated with protein @metal organic framework for targeted drug delivery: A biocompatible pH-Responsive nanocarrier for gemcitabine release on MCF‑7 human breast cancer cells

Silver and Antimicrobial Polymer Nanocomplexes to Enhance Biocidal Effects

Antimicrobial resistance has become a major problem over the years and threatens to remain in the future, at least until a solution is found. Silver nanoparticles (Ag-NPs) and antimicrobial polymers (APs) are known for their antimicrobial properties and can be considered an alternative approach to fighting resistant microorganisms. Hence, the main goal of this research is to shed some light on the antimicrobial properties of Ag-NPs and APs (chitosan (CH), poly-L-lysine (PLL), ε-poly-L-lysine (ε-PLL), and dopamine (DA)) when used alone and complexed to explore the potential enhancement of the antimicrobial effect of the combination Ag-NPs + Aps. The resultant nanocomplexes were chemically and morphologically characterized by UV-visible spectra, zeta potential, transmission electron microscopy, and Fourier-transform infrared spectroscopy. Moreover, the Ag-NPs, APs, and Ag-NPs + APs nanocomplexes were tested against Gram-positive Staphylococcus aureus (S. aureus) and the Gram-negative Escherichia coli (E. coli) bacteria, as well as the fungi Candida albicans (C. albicans). Overall, the antimicrobial results showed potentiation of the activity of the nanocomplexes with a focus on C. albicans. For the biofilm eradication ability, Ag-NPs and Ag-NPs + DA were able to significantly remove S. aureus preformed biofilm, and Ag-NPs + CH were able to significantly destroy C. albicans biofilm, with both performing better than Ag-NPs alone. Overall, we have proven the successful conjugation of Ag-NPs and APs, with some of these formulations showing potential to be further investigated for the treatment of microbial infections.

Polydopamine-Modified Zeolite Imidazole Framework Drug Delivery System for Photothermal Chemotherapy of Hepatocellular Carcinoma

Metal-organic frameworks (MOFs) are promising drug-delivering platforms for their intrinsic capability of loading and releasing different cargoes. To further extend their biomedical practices, the development of collaborative MOF systems with good biocompatibility and synergistic efficacy is essential. Herein, the near-infrared and pH dual-response collaborative zeolitic imidazolate framework-8 (ZIF-8) platform SOR@ZIF-8@PDA (SZP) was constructed, in which the chemotherapeutic drug sorafenib (SOR) was encapsulated in ZIF-8 and via polydopamine (PDA) coating on ZIF-8 by hierarchical self-assembly. PDA coating serves as a photothermal agent for PPT while reducing the toxicity of ZIF-8. SZP achieves intelligent release of therapeutic drugs by responding to the lower pH of the tumor microenvironment and thermal stimulation generated by near-infrared light irradiation. In addition, under light irradiation, SZP could effectively realize treatment of cancer cells through synergistic chemo-photothermal therapy, as evidenced by the enhanced cell apoptosis, inhibited tumor cell proliferation and migration. This collaborative MOFs system showed excellent biocompatibility and antitumor ability in vivo on a mouse HepG2 tumor model. Our results demonstrated that PDA-modified MOFs exhibited a fantastic good development prospect in biomedical applications.

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.

Vitamin A-modified ZIF-8 lipid nanoparticles for the therapy of liver fibrosis

Liver fibrosis (LF) is one of the major diseases that threaten human health. Until now, no effective drugs have been approved for clinical anti-liver fibrosis treatment. In this study, zeolitic imidazolate framework-8 (ZIF-8) lipid nanoparticles loaded with pirfenidone (PFD) and modified with vitamin A (VA) were constructed (VA-PFD@ZIF-8@DMPC NPs). PFD was embedded in ZIF-8 by the "one-pot" method, and the prepared ZIF-8 had a small particle size (84.3 nm) and high drug loading (54.46%). Moreover, the inherent pH sensitivity of ZIF-8 makes it stable in a normal physiological environment and collapsed in an acidic environment, thus controlling drug release and preventing drug leakage. Besides, the phospholipid layer makes the nano-drug delivery system dispersible and improves its biocompatibility. More importantly, VA is modified on the surface of nanoparticles (NPs), which can target the highly expressed retinol-binding protein receptor (RBPR) on the surface of hepatic stellate cells (HSCs), thereby accurately increasing the local drug concentration at the site of LF. In vivo experiments showed that VA-PFD@ZIF-8@DMPC NPs can reduce liver injury, improve the degree of LF, and exert specific therapeutic effects on LF. In conclusion, this nano-delivery system may become a novel and effective anti-liver fibrosis treatment.

Synthesis and characterization of biological macromolecules double emulsion based on carboxymethylcellulose/gelatin hydrogel incorporated with ZIF-8 as metal organic frameworks for sustained anti-cancer drug release

The field of nanotechnology has introduced novel prospects for drug delivery systems, which have the potential to supplant conventional chemotherapy with reduced adverse effects. Despite being a promising porous material, ZIF-8, a metal-organic framework, tends to agglomerate in water, which limits its applicability. In order to resolve this problem, we added ZIF-8 to hydrogels consisting of gelatin and carboxymethylcellulose. This improved their mechanical strength and stability while avoiding aggregation. We utilized double emulsions with the hydrogels' biological macromolecules to construct drug carriers with enhanced control over drug release. The nanocarriers were subjected to various analytical techniques for characterization, such as Fourier-transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), zeta potential, and dynamic light scattering (DLS). The findings of our study revealed that the mean size of the produced nanocarriers were 250 nm, and their zeta potential was -40.1 mV, which suggests favorable stability. The synthesized nanocarriers were found to exhibit cytotoxicity towards cancer cells, as evidenced by the results of MTT assays and flow cytometry tests. The cell viability percentage was determined to be 55 % for the prepared nanomedicine versus 70 % for the free drug. In summary, our study illustrates that the integration of ZIF-8 into hydrogels produces drug delivery systems with improved characteristics. Furthermore, the prepared nanocarriers exhibit potential for future investigation and advancement.

A Strategy for the Determination of Alkaline Phosphatase Based on the Self-Triggered Degradation of Metal-Organic Frameworks by Phosphate

Alkaline phosphatase (ALP) is widely present in the human body and is an important biomarker. Numerous ALP detection studies have been carried out, and ascorbic acid (AA) is often used as the reducing component in the sensors to monitor ALP levels since it can be produced from ascorbic acid 2-phosphate (AA2P) hydrolysis in the presence of ALP. However, it is well-known that AA is a strong reducing agent and can be easily oxidized. The disproportion between oxidized AA and reduced AA reactions results in the generation of AA free radicals with single electrons that may lead to inaccurate results in assays. To solve this problem, we synthesized a core-shell metal-organic framework sensor (PATP-Au@ZIF-8 NP) and used it as a sensitive and accurate ALP detection sensor with self-triggered control of phosphate ions (Pi) to avoid the potential inaccuracy of the method that uses AA as the reducing component. By establishing a physical shell on the surface of the gold nanoparticles (Au NPs), the sensor not only can eliminate the random assembly of metal nanoparticles caused by plasma exposure but also can generate self-triggering of Pi caused by ALP. Pi can decompose ZIF-8 through coordination with Zn²⁺ and thus can destroy the ZIF-8 shell structure of the prepared PAZ NPs. Au NPs are released and then become aggregated, in turn causing the SERS "hot spot" area to increase. The enhancement of the SERS signals was found to be directly associated with the level of Pi released from ALP-triggered hydrolysis. The response of the strategy was linear at ALP concentrations ranging from 0.1 to 150 mU/mL (r = 0.996) with a detection limit of 0.03 mU/mL. Lastly, the developed strategy was employed in the evaluation of ALP inhibitors, and the possibility to implement the developed SERS strategy for rapid and selective analysis of ALP in human serum was demonstrated.

Gallium Metal-Organic Nanoparticles with Albumin-Stabilized and Loaded Graphene for Enhanced Delivery to HCT116 Cells

Background

Gallium (III) metal-organic complexes have been shown to have the ability to inhibit tumor growth, but the poor water solubility of many of the complexes precludes further application. The use of materials with high biocompatibility as drug delivery carriers for metal-organic complexes to enhance the bioavailability of the drug is a feasible approach.

Methods

Here, we modified the ligands of gallium 8-hydroxyquinolinate complex with good clinical anticancer activity by replacing the 8-hydroxyquinoline ligands with 5-bromo-8-hydroxyquinoline (HBrQ), and the resulting Ga(III) + HBrQ complex had poor water solubility. Two biocompatible materials, bovine serum albumin (BSA) and graphene oxide (GO), were used to synthesize the corresponding Ga(III) + HBrQ complex nanoparticles (NPs) BSA/Ga/HBrQ NPs and GO/Ga/HBrQ NPs in different ways to enhance the drug delivery of the metal complex.

Results

Both of BSA/Ga/HBrQ NPs and GO/Ga/HBrQ NPs can maintain stable existence in different solution states. In vitro cytotoxicity test showed that two nanomedicines had excellent anti-proliferation effect on HCT116 cells, which shown higher level of intracellular ROS and apoptosis ratio than that of cisplatin and oxaliplatin. In addition, the superior emissive properties of BSA/Ga/HBrQ NPs and GO/Ga/HBrQ NPs allow their use for in vivo imaging showing highly effective therapy in HCT116 tumor-bearing mouse models.

Conclusion

The use of biocompatible materials for the preparation of NPs against poorly biocompatible metal-organic complexes to construct drug delivery systems is a promising strategy that can further improve drug delivery and therapeutic efficacy.

Mesoporous Polydopamine Loaded Pirfenidone Target to Fibroblast Activation Protein for Pulmonary Fibrosis Therapy

Recently, fibroblast activation protein (FAP), an overexpressed transmembrane protein of activated fibroblast in pulmonary fibrosis, has been considered as the new target for diagnosing and treating pulmonary fibrosis. In this work, mesoporous polydopamine (MPDA), which is facile prepared and easily modified, is developed as a carrier to load antifibrosis drug pirfenidone (PFD) and linking FAP inhibitor (FAPI) to realize lesion-targeted drug delivery for pulmonary fibrosis therapy. We have found that PFD@MPDA-FAPI is well biocompatible and with good properties of antifibrosis, when ICG labels MPDA-FAPI, the accumulation of the nanodrug at the fibrosis lung in vivo can be observed by NIR imaging, and the antifibrosis properties of PFD@MPDA-FAPI in vivo were also better than those of pure PFD and PFD@MPDA; therefore, the easily produced and biocompatible nanodrug PFD@MPDA-FAPI developed in this study is promising for further clinical translations in pulmonary fibrosis antifibrosis therapy.

Effectiveness of 5-Fluorouracil and gemcitabine hydrochloride loaded iron‑based chitosan-coated MIL-100 composite as an advanced, biocompatible, pH-sensitive and smart drug delivery system on breast cancer therapy

This study was planned to evolve the bioavailability and therapeutic efficiency of Gemcitabine (GEM) and 5-Fluorouracil with decreased side effects using MIL-100 nano-composite as carrier. Impregnation approach was used for encapsulation of 5-Fluorouracil alone and with GEM inside the MIL-100. The formed 5-Fluorouracil@MIL-100 and 5-Fluorouracil-GEM@MIL-100 were then coated with chitosan, sequentially chelated with iron(III) and conjugated with quercetin, eventually obtaining a multifunctional MIL-100 nanocarrier. The hybrid nanocarrier nascency was verified by different characterization results. pH-sensitive releases of 5-Fluorouracil and GEM were observed because of the inherent pH-dependent stability of MIL-100. Additionally, we evaluated the anti-cancer activity of these nanocarriers through WST-1 analysis and acridine orange staining in MCF-7 human breast cancer and HUVEC control cell lines. Our findings showed that all nanocarriers exhibited anti-cancer activity and induced apoptosis in MCF-7 cells. However, 5-Fluorouracil@MIL-100 and chitosan-coated 5-Fluorouracil@MIL-100 with quercetin were more effective than other nanocarriers in MCF-7 cells (p < 0.05). Moreover, we observed cytotoxicity in HUVEC cells due to the adverse side effects of chemotherapy drugs. However, chitosan coated nanocarriers with quercetin were less toxic on HUVEC cells at particularly 1 µg/mL. Therefore, MIL-100 could be used for a promising chemotherapeutic drugs delivery and chitosan coated drugs with quercetin could be useful for reducing toxicity on normal cells.