An enzyme-responsive colon-specific delivery system was developed based on hollow mesoporous silica spheres (HMSS) to which biodegradable chitosan (CS) was attached via cleavable azo bonds (HMSS–N=N–CS). Doxorubicin (DOX) was encapsulated in a noncrystalline state in the hollow cavity and mesopores of HMSS with the high loading amount of 35.2%. In vitro drug release proved that HMSS–N=N–CS/DOX performed enzyme-responsive drug release. The grafted CS could increase the biocompatibility and stability and reduce the protein adsorption on HMSS. Gastrointestinal mucosa irritation and cell cytotoxicity results indicated the good biocompatibility of HMSS and HMSS–N=N–CS. Cellular uptake results indicated that the uptake of DOX was obviously increased after HMSS–N=N–CS/DOX was preincubated with a colonic enzyme mixture. HMSS–N=N–CS/DOX incubated with colon enzymes showed increased cytotoxicity, and its IC₅₀ value was three times lower than that of HMSS–N=N–CS/DOX group without colon enzymes. The present work lays the foundation for subsequent research on mesoporous carriers for oral colon-specific drug delivery.

To effectively inhibit the growth of breast cancer cells (MDA-MB-231 cells) by the combination method of chemotherapy and magnetic hyperthermia, we fabricated a biomimetic drug delivery (CSiFePNs) system composed of mesoporous silica nanoparticles (MSNs) containing superparamagnetic ferroferric oxide and Paclitaxel (PTX) coated with MDA-MB-231 cell membranes (CMs). In the in vitro cytotoxicity tests, the MDA-MB-231 cells incubated with CSiFePNs obtained IC₅₀ value of 0.8 μgL⁻¹, 3.5-fold higher than that of SiFePNs. The combination method of chemotherapy and magnetic hyperthermia can effectively inhibit the growth of MDA-MB-231 cells.

A spherical iron oxide precursor was prepared using a solvothermal method, and then treated thermally at 400°C to obtain α-Fe₂O₃ nanoparticles. The structures and morphology of the as-obtained products were characterized using X-ray diffraction (XRD), transmission electron microscopy (TEM), and scanning electron microscopy (SEM). The results showed that the diameter of the α-Fe₂O₃ nanoparticles was approximately 500 nm. In addition, we formed the α-Fe₂O₃ nanoparticles into a thick film as a gas sensor and performed a gas sensing test. When the working temperature was set at 250°C, the α-Fe₂O₃ nanoparticle displayed very good selectivity and high sensitivity for trimethylamine (TMA). The minimum detection was as low as 1 ppm, and the response value for 100 ppm TMA gas was 27.8. Taken together, our findings illustrated that the α-Fe₂O₃ nanoparticles could be used as a gas-sensitive material to test the freshness of fish.

In this study, glycyrrhetinic acid (GA) liposomes were successfully prepared using lyophilization monophase solution method. Preformulation studies comprised evaluation of solubility of soybean phosphatidylcholine (SPC), cholesterol, and GA in tert-butyl alcohol (TBA)/water co-solvent. The influences of TBA volume percentage on sublimation rate were investigated. GA after lyophilization using TBA/water co-solvent with different volume percentage was physicochemically characterized by DSC, XRD, and FTIR. The XRD patterns of GA show apparent amorphous nature. FTIR spectroscopy results show that no chemical structural changes occurred. Solubility studies show aqueous solubility of GA is enhanced. The optimum formulation and processing variables of 508 mg SPC, 151 mg cholesterol, 55% volume percentage of TBA, 4:1 trehalose/SPC weight ratio were obtained after investigating by means of Box-Benhnken design and selection experiment of lyoprotectant. Under the optimum conditions, satisfactory encapsulation efficiency (74.87%) and mean diameter (191 nm) of reconstituted liposomes were obtained. In vitro drug release study showed that reconstituted liposomes have sustained-release properties in two kinds of release medium. Furthermore, in vitro cell uptake study revealed that uptake process of drug-loaded liposomes by Hep G2 cells is time-dependent.

Applicability of multi‑walled carbon nanotubes (MWCNTs) in loading dipyridamole (DDM), a poorly soluble drug, was evaluated. Additionally, the effect of drug‑loading efficiency on the release behavior of the MWCNT‑DDM system was also investigated. DDM as a model drug was incorporated into MWCNTs with different drug‑loading rates (10, 25 and 50%) using the solvent deposition method. The MWCNT‑DDM system was successfully established and characterized using common solid‑state characterization methods. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), nitrogen adsorption analysis and Fourier transform‑infrared (FT‑IR) spectroscopy were carried out to observe the progress of drug loading. X‑ray diffraction (XRD) and differential scanning calorimetry (DSC) were used to systematically assess the crystalline state of the DDM after being loaded into the MWCNTs. Improvements in dissolution rate were evaluated by the dissolution test. The results revealed that with the increase of drug loading, the form of DDM in the MWCNTs changed from amorphous to crystalline state. Also, the release rate of DDM decreased upon increasing the drug‑loading rate of carriers. In conclusion, MWCNTs are proven to be promising carriers for loading DDM.