To increase the bioavailability and water solubility of hydrophobic medicine, an amphiphilic block copolymer, polycaprolactone-block-polyhydroxyethyl acrylamide (PCL-b-PHEAA), was synthesized. The copolymer can self-assemble into micelles by dialysis. The micelles were characterized by the Tyndall effect, static drop method, fluorescence spectrometry, dynamic light scattering, scanning electron microscopy and transmission electron microscopy. Ibuprofen was encapsulated inside the micelles by dialysis as a model medicine. The results show that the amphiphilic copolymer forms a uniform micelle system, with spherical micelles dispersed well in solution which have a low critical micelle concentration. In addition, the system shows good amphipathic behavior. Average particle size of a micelle is 104 nm, which increases a lot after drug loading and standing for half a month. In the first few hours, the cumulative release of the drug increases gradually; the rate of increase in the first ten hours is faster, then reaching a plateau which tends to be flat finally. It is similar under two different pH conditions. This biocompatible, biodegradable amphiphilic block copolymer has potential applications in the biomedical field.
Chiral pesticide enantiomers play an important role in regulating plant growth due to their different physiology, pharmacology, and toxicity. However, efficient separation of chiral pesticides remains a global challenge. Ibuprofen (IBU), a chiral compound that has an important influence on the growth of plants, was chosen as a model molecule of plant growth regulator. Herein, in this work, l-Trp-l-Ala-P6 was chosen as a chiral ligand, and STI-NH2 was chosen as a guest molecule. We designed and fabricated chiral micropore membranes with both high selectivity and high flux effects using the layer-by-layer (LBL) self-assembly method, which achieved the selective separation of R-IBU from the racemic IBU accompanied by high flux and high selectivity. Meanwhile, the effects of separated R-IBU and S-IBU on the growth of wheat seedlings were studied. The results showed that after separation by the LBL-assembled chiral micropore-4, R-IBU exhibited a more effective activity in promoting the growth of wheat seedlings. This LBL-assembled chiral micropore membrane may have potential application in the separation of chiral pesticides in the future.
A defect-related luminescent mesoporous silica nanoparticle (DLMSN) with simultaneous excellent luminescence, high drug loading efficiency and release capacity was prepared upon calcination of 3-aminopropyltriethoxysilane (APTES)-functionalized mesoporous silica nanoparticle (AP-MSN)
under a relatively moderate temperature. Under ultraviolet excitation at 365 nm, DLMSN exhibited intense white-blue emission with a range of 400–500 nm, which was inferred to originate from the effective carbon or nitrogen defect in the particle causing by APTES calcination. Additionally,
the luminescence intensity of DLMSN was significantly affected by APTES concentration and calcination temperature during the preparation procedure. Within all the tested values, the maximum luminescence intensity was achieved when APTES concentration and calcination temperature were 0.851
mmol and 300 °C, respectively. The drug storage and release tests demonstrated that DLMSN had efficient drug storage and good pH-dependent release for ibuprofen (IBU). Interestingly, ibuprofen-loaded DLMSN (IBU@DLMSN) still exhibit an intense luminescence with an emission peak at around
410 nm under 365 nm excitation, which gradually increased with the sustained release of IBU from IBU@DLMSN. These results suggest that the as-prepared DLMSN may have potential as a detectable nanocarrier in the drug delivery field.
危险品化学品经营许可证（带存储）