One-pot approach to couple the crystallization of CaCO(3) nanoparticles and the in situ symmetry-breaking assembly of these crystallites into hollow spherical shells was developed under the templating effect of a soluble starch. Further functional study using HP-a as an anticancer drug carrier (DOX) demonstrated its advantages for localizing drug release by the pH value-sensitive structure and enhancing cytotoxicity by increasing cellular uptake, perinuclear accumulation, and nuclear entry.

Fluorescent microspheres are widely used as biological tracers. In this study, uniformly sized chitosan microspheres crosslinked with glutaraldehyde (CG microspheres) and formaldehyde (CF microspheres) are successfully prepared by the Shirasu Porous Glass (SPG) membrane emulsification technique. Selectively reduced CG microspheres (SRCG microspheres) are obtained by NaBH4 reduction. These chitosan microspheres are found to exhibit fluorescent properties without conjugation to any fluorescent agent. The fluorescence color varies with different crosslinkers and can be modulated by further chemical reduction, whereas the fluorescence intensity can be controlled by tuning the particle size and degree of crosslinking. The autofluorescence of the microspheres is applied to study the phagocytosis of HepG2 cells using the microspheres as novel tracers. Quantitative and qualitative evaluations show that these chitosan microspheres serve as bright, inert, durable, and extremely photostable tracers.

microRNAs are regarded as promising drugs for glioma gene therapy. However, conventional administration routes, such as oral administration and intravenous infusion, present low efficiency due to the blood-brain barrier and intercellular retention, thereby limiting their application. Recent studies showed poly(amido amine) (PAMAM) was a candidate carrier due to its high solubilization, delayed release and low toxicity. In the present study, U251 human brain glioma cells were transfected with the miR-7 gene using PAMAM as the vector to determine the transfection efficiency and therapeutic effects in vivo and in vitro. We found that PAMAM exhibited higher transfection efficiency and longer duration of action compared with liposome delivery, and miR-7 efficiently silenced some genes involved in the epidermal growth factor receptor (EGFR) pathway and achieved favorable effects in treating glioma in vivo and in vitro. These investigations provide a basis for developing high-efficiency micromolecular drug delivery.