The development of advanced gene/drug codelivery carriers with stimuli‐responsive release manner for complementary cancer therapy is desirable. In this study, novel disulfide‐bridged and doxorubicin (DOX)‐embedded degradable silica nanoparticles (DS‐DOX) with unique self‐destruction features are synthesized by a facile one‐pot method. In order to realize codelivery of genes and drugs, the surface of DS‐DOX nanoparticles is readily functionalized with the assembled polycation (CD‐PGEA), comprising one β‐cyclodextrin core and two ethanolamine‐functionalized poly(glycidyl methacrylate) arms, to achieve DS‐DOX‐PGEA. The redox‐responsive self‐destruction behavior of DS‐DOX imparts DS‐DOX‐PGEA with a better ability to release anticancer drug DOX, while the low‐toxic hydroxyl‐rich CD‐PGEA brushes can efficiently deliver genes for cancer treatment. Very interestingly, the degradation process of DS‐DOX starts from the outside, while the destruction of the degradable silica (DS) nanoparticles without DOX begins from the center of the nanoparticles. The embedded DOX inside the DS‐DOX nanoparticles can significantly influence the structures and facilitate the cellular uptake and the subsequent gene transfection. The as‐developed DS‐DOX‐PGEA nanostructure with coordinating biodegradability, stimuli‐responsiveness, and controlled release manner might be desirable gene/drug codelivery carriers for clinical cancer treatment.

Nuclear magnetic relaxation times T1 and T2 were measured in ferritin solutions at field strengths from 0.04 to 1.5 T. T1 was relatively constant, but 1/T2 increased linearly with field strength, in agreement with earlier MRI observations in the monkey brain. This finding supports the theory that ferritin is responsible for T2 shortening in brain nuclei containing iron. The linear dependence of 1/T2 on magnetic field is unique and not explained by present theories of the magnetic properties of ferritin.

Development of advanced wound dressing materials with rapid healing rates is in urgent demand for wound cares. A suitable microenvironment will promote cell proliferation and migration, which benefits to early wound healing and prevents inflammations and scars. In this work, N-carboxymethyl chitosan- and alginate-based hydrogels are prepared via both electrostatic interaction and divalent chelation with epidermal growth factor (EGF) payload to promote the cell proliferation and wound healing. The dual-crosslinked hydrogels are investigated in terms of rheology, water retention ability, and the release rate of EGF. Moreover, such amorphous hydrogel can promote cell proliferation and accelerate wound healing. The present study demonstrates that dual-crosslinked polysaccharide hydrogels are promising in wound care management.

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