In recent years, metal organic frameworks (MOFs) have been widely developed as vehicles for the effective delivery of drugs to tumor tissues. Due to the high loading capacity and excellent biocompatibility of MOFs, they provide an unprecedented opportunity for the treatment of cancer. However, drugs which are commonly used to treat cancer often cause side effects in normal tissue accumulation. Therefore, the strategy of drug targeting delivery based on MOFs has excellent research significance. Here, we introduce several intelligent targeted drug delivery systems based on MOFs and their characteristics as drug-loading systems, and the challenges of MOFs are discussed. This article covers the following types of MOFs: Isoreticular Metal Organic Frameworks (IRMOFs), Materials of Institute Lavoisier (MILs), Zeolitic Imidazolate Frameworks (ZIFs), University of Oslo (UiOs), and MOFs-based core-shell structures. Generally, MOFs can be reasonably controlled at the nanometer size to effectively achieve passive targeting. In addition, different ligands can be modified on MOFs for active or physicochemical targeting. On the one hand, the targeting strategy can improve the concentration of the drugs at the tumor site to improve the efficacy, on the other hand, it can avoid the release of the drugs in normal tissues to improve safety. Despite the challenges of clinical application of MOFs, MOFs have a number of advantages as a kind of smart delivery vehicle, which offer possibilities for clinical applications.

Oridonin (ORI) is a natural active ingredient with strong anticancer activity. But its clinical use is restricted due to its poor water solubility, short half-life, and low bioavailability. The aim of this study is to utilize the metal organic framework material MOF-5 to load ORI in order to improve its release characteristics and bioavailability. Herein, MOF-5 was synthesized by the solvothermal method and direct addition method, and characterized by Scanning Electron Microscopy (SEM), X-Ray Diffraction (XRD), Fourier Transform Infrared Spectrometer (FTIR), Thermogravimetric Analysis (TG), Brunauer–Emmett–Teller (BET), and Dynamic Light Scattering (DLS), respectively. MOF-5 prepared by the optimal synthesis method was selected for drug-loading and in vitro release experiments. HepG2 cells were model cells. MTT assay, 4′,6-diamidino-2-phenylindole (DAPI) staining and Annexin V/PI assay were used to detect the biological safety of blank carriers and the anticancer activity of drug-loaded materials. The results showed that nano-MOF-5 prepared by the direct addition method had complete structure, uniform size and good biocompatibility, and was suitable as an ORI carrier. The drug loading of ORI@MOF-5 was 52.86% ± 0.59%. The sustained release effect was reliable, and the cumulative release rate was about 87% in 60 h. ORI@MOF-5 had significant cytotoxicity (IC50:22.99 μg/mL) and apoptosis effect on HepG2 cells. ORI@MOF-5 is hopeful to become a new anticancer sustained release preparation. MOF-5 has significant potential as a drug carrier material.

A MIL series metal‒organic framework (MOF), MIL-100(Fe), was successfully synthesized at the nanoscale and fully characterized by TEM, TGA, XRD, FTIR, DLS, and BET. A toxicological assessment was performed using two different cell lines: human normal liver cells (HL-7702) and hepatocellular carcinoma (HepG2). In vitro cytotoxicity of MIL-100(Fe) was evaluated by the MTT assay, LDH releasing rate assay, DAPI staining, and annexin V/PI double staining assay. The safe dose of MIL-100(Fe) was 80 μg/mL. It exhibited good biocompatibility, low cytotoxicity, and high cell survival rate (HL-7702 cells’ viability >85.97%, HepG2 cells’ viability >91.20%). Therefore, MIL-100(Fe) has a potential application as a drug carrier.

Houpo Wenzhong Decoction (HWD) as a classical prescription has been widely used for hundreds of years. However, the quality of HWDs is difficult to control because of its herb materials from different regions. It is a new idea to use HPLC fingerprints, LTQ-ESI-Orbitrap-MS, and network pharmacology in combination to screen common components (CCs) as potential quality control indicators. In this paper, the fingerprints of HWDs were established, which were used to determine HWDs compounded from different sources of traditional Chinese medicines (TCMs). Through the similarity analysis, 45 CCs were selected. UHPLC-LTQ-ESI-Orbitrap-MS was used to carry out the chemical composition analysis of HWD. Seventy-three chemical constituents were distinguished, and 30 CCs were identified. Through network pharmacology, networks of candidate CCs, diseases, and candidate targets were constructed. Finally, four CCs were screened as potential active ingredient markers of HWD, and a method for content determination of these four components was established. A rapid, reasonable, and effective method for quality evaluation and control of HWDs was established. It provides a reference for the further development and research of HWDs and a new way of thinking for the research of other Chinese medicine prescriptions.

In this work, microwave-assisted ionic liquids treatment, followed by hydro-distillation (MILT-HD), as an efficient extraction technology, was used to extract essential oil. The purpose for this was to use multivariate analysis (MVA) models to investigate the effects of potential critical process parameters on the extraction efficiency of essential oil, and explore the mechanism of ionic liquids (ILs). According to the design of experiment (DoE), under optimal process conditions, the extraction efficiency of essential oil was dramatically enhanced, and had low energy demands. Since little is known regarding those mechanisms, according to the non-covalent interaction analysis, the underlying mechanism for ILs improving extraction efficiency was explored based on the density functional theory (DFT). The results showed that ILs could form intense non-covalent bond interaction with cellulose. It helped destroy the network hydrogen bond structure of cellulose in plant cells and caused the essential oils in the cells to be more easily exposed to the extraction solution, thereby accelerating extraction efficiency. Based on this work, it is conducive to understand the MILT-HD process better and gain knowledge of the mechanism of ILs.