Tetraphenylsilane-Cored Star-Shaped Polymer Micelles with pH/Redox Dual Response and Active Targeting Function for Drug-Controlled Release

This paper presents the design and synthesis of star-shaped copolymers with two poly­[2-(diethylamino)­ethyl methacrylate] and poly­(ethylene glycol) blocks linked via a disulfide bond and each end of the four arms capped by folic acid (FA), from which the prepared nanodrug carriers simultaneously possess pH/redox dual response and active targeting functions. The polymer micelles exhibit excellent stability as reflected by their low critical micelle concentration values of 1.03–2.51 mg/L. The doxorubicin (DOX)-loaded polymer micelles are in the range of 108 to 143 nm, and the DOX-loading capacities are found to be up to 32.3%. The sensitive pH and redox responses are demonstrated by examining the drug release behaviors under the varied acidic condition from pH 7.4 to 5.0 and the glutathione concentrations from 0 to 10 mM, respectively. Moreover, the observation of confocal laser scanning microscopy confirms that the functionalization of arm ends by FA indeed enhances the internalization of DOX-loaded micelle particles in HeLa cells. As a result, the DOX-loaded nanocarriers can deliver therapeutic drugs to target HeLa cells, and the viability of HeLa cells (10.1%) approaches the value of the pristine DOX (9.98%), showing promising application as drug delivery nanocarriers for safe and highly efficient cancer therapy

Synthesis of Fluorescent Micro- and Mesoporous Polyaminals for Detection of Toxic Pesticides

This paper presents the first report on employing fluorescent porous organic polymers as sensors for the detection of toxic pesticides. Specifically, fluorescent micro- and mesoporous polyaminals with pendant triphenylamine and dibromotriphenylamine chromophore groups are synthesized, which exhibit BET surface area up to 507 m² g^–1, adjustable pore sizes in the range from 0.5 to 36.2 nm and can emit bright turquoise light under the ultraviolet lamp. Using the insecticide (fenitrothion) and herbicides (trifluralin and glyphosate) as analytes, the chemosensing properties are investigated by correlating the porosity parameters and chemical structure of the polymers with the molecular sizes and the energy in the lowest unoccupied molecular orbital of pesticides. Moreover, the effects of different acid–base conditions and solvents including ethanol, water, chloroform, tetrahydrofuran, and <i>N</i>,<i>N</i>-dimethyl­formamide on the chemosensing sensitivity of the polymers are also studied in detail. Particularly, the chemosensing test paper fabricated with the fluorescent polymer rapidly becomes dark upon contacting the pesticide solutions at an extremely low concentration, and the quenching degree is unchanged after repeating the experiments for 10 times, exhibiting the capability of sensible and reusable detection for pesticides