Chalcogen-Atom-Annulated Perylene Diimide Trimers for Highly Efficient Nonfullerene Polymer Solar Cells.

This communication reports the synthesis of two novel chalcogen-atom-annulated perylene diimide (PDI) trimers with twisted structures, TriPDI-S and TriPDI-Se, for efficient nonfullerene polymer solar cells. TriPDI-Se exhibits more compact molecular arrangement due to the stronger intermolecular interactions induced by the selenium atom. This selenium annulation endows TriPDI-Se with improved absorption and crystallinity in its blend film. The resulting devices exhibit enhanced Jsc of 17.15 mA cm-2 and fill factor (FF) of 66.8%, which are much higher than those of TriPDI-S devices (Jsc = 16.71 mA cm-2 ; FF = 63.6%). Although TriPDI-Se exhibits lower-lying energy levels, TriPDI-Se devices still obtain a higher Voc of 0.77 V compared to TriPDI-S devices (Voc = 0.74 V), which is mainly originated from the reduced recombination in the related devices. Finally, the power conversion efficiency is significantly elevated from 7.86% for TriPDI-S devices to 8.82% for TriPDI-Se devices.

Evaluation in vitro and in vivo of curcumin-loaded mPEG-PLA/TPGS mixed micelles for oral administration.

The aim of this work is to prepare and characterize curcumin-loaded methoxy poly(ethylene glycol)-poly(lactide) (mPEG-PLA)/D-α-tocopherol polyethylene glycol 1000 succinate (TPGS) mixed micelles (CUR-MPP-TPGS-MMs), analyze the influence of formulation on enhancing the solubility of curcumin in water, and evaluate the improvement of intestinal absorption after oral administration. CUR-MPP-TPGS-MMs were prepared using the thin film diffusion method and optimized with the uniform design. The optimal CUR-MPP-TPGS-MMs were provided with high drug-loading (16.1%), small size (46.0 nm) and spherical shape. Low critical micelle concentration (CMC) and superior dilution stability showed that CUR-MPP-TPGS-MMs could keep integrity during the dilution of gastrointestinal fluid. In vitro drug release study indicated a sustained release of curcumin from CUR-MPP-TPGS-MMs in simulated gastrointestinal solution. The absorption mechanism of passive diffusion was obtained by measuring in situ intestinal absorption of CUR-MPP-TPGS-MMs in rats, and the best absorption segment was found to be the duodenum. The pharmacokinetics was evaluated in rats at the dose of 75 mg/kg by intragastric administration. The Cmax and mean retention time (MRT0-24) for CUR-MPP-TPGS-MMs were both increased, and the relative bioavailability of micelle formulation to curcumin suspension was 927.3%. These results suggested that mPEG-PLA/TPGS mixed micelle system (MPP-TPGS-MMs) showed great potential in improving oral bioavailability of curcumin.

Novel in situ gel systems based on P123/TPGS mixed micelles and gellan gum for ophthalmic delivery of curcumin.

Curcumin, a natural polyphenol compound, has been widely reported for diverse pharmacological effects and already been investigated for eye diseases. However, the water-insolubility of curcumin and the inherent penetration barriers in cornea make it difficult for curcumin to enter eye. This work aimed to develop ion-sensitive curcumin-loaded Pluronic P123 (P123)/D-a-tocopheryl polyethylene glycolsuccinate (TPGS) mixed micelle in situ gels (CUR-MM-ISGs) to prolong ocular retention time and improve cornea permeability. Central composite design-response surface methodology was applied for the optimization of curcumin-loaded P123/TPGS mixed micelles (CUR-MMs). Characterization tests showed that CUR-MMs were in spherical shape with small size and low critical micelle concentration. After dispersing the micelles in gellan gum solution (0.2%, w/w) at the ratio of 3:1 and 1:1 (v/v), respectively, CUR-MM-ISGs were formed and presented transparent appearance. Sustained release profile was obtained in vitro for both CUR-MM-ISGs (3:1 or 1:1, v/v). The irritation test proved that CUR-MM-ISGs as ophthalmic formulations were gentle and biocompatible towards ocular tissues. In addition, the ex vivo corneal penetration study indicated that the cumulative drug permeation amount of CUR-MM-ISGs (3:1, v/v) was respectively 1.16-fold and 1.32-fold higher than CUR-MM-ISGs (1:1, v/v) and curcumin solution. It can be concluded from these results that the developed ion-sensitive mixed micelle in situ gel system is a potential ophthalmic delivery carrier for curcumin as a poorly soluble drug.

Curcumin loaded mixed micelles composed of Pluronic P123 and F68: preparation, optimization and in vitro characterization.

In this study, curcumin (Cur) loaded mixed micelles (Cur-PF), composed of Pluronic P123 (P123) and Pluronic F68 (F68), was prepared using the thin-film hydration method and evaluated in vitro. The preparation process was optimized with a central composite design (CCD). The average size of the mixed micelles was 68.2 nm, and the encapsulating efficiency for Cur was 86.93%, and 6.996% for drug-loading. Compared with the Cur propylene glycol solution, the in vitro release of Cur from Cur-PF presented the sustained-release property. The in vitro cytotoxicity assay showed that the IC(50) values on MCF-7 cells for Cur-PF and free Cur in DMSO solution were 5.04 µg/mL and 8.35 µg/mL, while 2.52 µg/mL and 8.27 µg/mL on MCF-7/ADR cells. It could be concluded from the results that P123/F68 mixed micelles might serve as a potential nanocarrier to improve the solubility and biological activity of Cur.