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Natural pectin is an important carrier for delivering drugs in biomedical research, however, there are only a few reports on the preparation of pectin nanoparticles, especially a particle size of below 100 nm with high yield. Here we design pectin-dihydroartemisinin/hydrooxycampothecin nanoparticles (PDC-H NPs) through a self-assembly method. The prepared PDC-H NPs contained hydrophilic part of pectin and hydrophobic anticancer drugs of dihydroartemisinin and hydroxycamptothecin, which could increase drug loading, improve water solubility, and achieve controlled release of drugs. The results indicated that the particle size of PDC-H NPs was about 70 nm, drug-loaded efficiency of DHA was 20.33 wt %, and encapsulation efficiency of HCPT was 14.11 wt %. PDC-H NPs exhibited a higher cytotoxicity, the blood retention time of PDC-H NPs was 4.8-fold longer than DHA and was 6.8-fold longer than HCPT. In addition, effective cellular uptake exhibited an obvious synergistic effect compared with DHA and HCPT. 4T1 tumor-bearing mice also showed a higher survival rate than free DHA and free HCPT. The result show that the self-assembled PDC-H NPs is a promising anticancer drug for codelivery.

A novel composite adsorbent of ZIF-9 nanoparticles growing on super-macroporous microspheres (SMM) was synthesized via in situ growth method for adsorptive removal of Congo red from water.

An efficient and environmental-friendly extraction method has been developed for extraction of ursolic acid (UA) from Hedyotis diffusa by using subcritical water extraction (SWE). The experiments were carried out at different particle sizes (20-100 mesh), extraction temperature (120-200 • C), extraction time (10-50 min), solvent/solid ratio (20-40 mL/g), and extraction pressure (0.6-3.0 MPa). Response surface methodology (RSM) was employed to optimize SWE conditions, and the maximum UA yield was 6.45 mg/g material. Optimal conditions are as follows: Particle size of 80 mesh, extraction temperature at 157 • C and a solvent/solid ratio of 30 mL/g. The model of experimental response was proved to predict the experimental results very well and demonstrated that UA yield was mainly depended on solvent/solid ratio, followed by particle size and temperature. The purified extract was analyzed by electrospray ionization time-of-flight mass spectrometry (ESI-TOF-MS). The acquired precursor ion was m/z 455.3532, which is consistent with calculated value of UA. Furthermore, different extraction methods, including maceration extraction, heat reflux extraction, ultrasonic extraction, microwave-assisted extraction, and SWE were comparatively analyzed, which indicated that SWE was a time-saving, cost-saving and environment-friendly extraction technology for extraction of UA from Hedyotis diffusa.

ZIFs type metal-organic frameworks have been found to rapidly remove organic contaminants from water by adsorption. But ZIFs crystals are not suitable to be directly used as stationary phases of solid-phase extraction (SPE) process, because of the non-spherical morphology. This study reports a novel composite adsorbent, ZIF-67 composite microspheres (ZIF-67 CMs), synthesized via in-situ growing ZIF-67 nanoparticles (ZIF-67 NPs) on the outer surface of resin microspheres (RMs). The assynthesized ZIF-67 CMs were characterized by SEM, XRD, FTIR, BET and TGA experiments, and the removal performance of the ZIF-67 CMs to anion dyes were investigated. It was found that the ZIF-67 CMs showing microsphere morphology were successfully assembled by growing ZIF-67 NPs on RMs and exhibited favorable performance to rapidly adsorptive remove two kinds of anion dyes (Brilliant Blue G and Congo red) from water. The removal rates of the ZIF-67 CMs to a 100 mg L À1 dye solution reached 95.9% and 99.1% in a 1 h and 5 h static adsorption, respectively. The ZIF-67 CMs showing rapid adsorption performance were further studied as stationary phases in SPE procedures for decolorizing dye solutions. The ZIF-67 CMs can efficiently remove more than 99% of dyes at a flow rate of 1.0 mL min À1 in a 5 min operation. The excellent SPE performance of ZIF-67 CMs indicates the potential applications for efficiently concentrating or purifying liquid mixtures by using ZIF-67 CMs or other ZIFs composite microspheres.[a] J.