Modification of the distribution of humic acid complexations by introducing microbubbles to membrane distillation process for effective membrane fouling alleviation.

Membrane fouling caused by inorganic ions and natural organic matters (NOMs) has been a severe issue in membrane distillation. Microbubble aeration (MB) is a promising technology to control membrane fouling. In this study, MB aeration was introduced to alleviate humic acid (HA) composited fouling during the treatment of simulative reverse osmosis concentrate (ROC) by vacuum membrane distillation (VMD). The objective of this work was to explore the HA fouling inhibiting effect by MB aeration and discuss its mechanism from the interfacial point of view. The results showed that VMD was effective for treating ROC, followed by a severe membrane fouling aggravated with the addition of 100 mg/L HA in feed solution, resulting in 45.7% decline of membrane flux. Analysis using the Derjaguin-Landau-Verwey-Overbeek (DLVO) theory and zeta potential distribution of charged particles proved the coexistence of HA and inorganic cations (especially Ca2+), resulting in more serious membrane fouling. The introduction of MB aeration exhibited excellent alleviating effect on HA-inorganic salt fouling, with the normalized flux increased from 19.7% to 37.0%. The interfacial properties of MBs played an important role, which altered the zeta potential distributions of charged particles in HA solution, indicating that MBs adhere the HA complexations. Furthermore, this mitigating effect was limited at high inorganic cations concentration. Overall, MBs could change the potential characteristics of HA complexes, which also be used for other similar membrane fouling alleviation.

[Pharmacokinetic study of Polydopamine Guttate Pills loaded with active components of Sarcandrae Herba in rats].

An ultra-high performance liquid chromatography-tandem mass spectrometry(UHPLC-MS/MS) method was established for the determination of active components of Sarcandrae Herba, and applied to the pharmacokinetics study of multiple dosage forms. After SD rats were administered by gavage with three dosage forms [Sarcandrae Herba extract, commercial Sarcandrae Herba Guttate Pills, and polydopamine guttate pills loaded with active components of Sarcandrae Herba(PDA-Sg Guttate Pills)], blood samples were collected from the inner canthus at different time points. After protein precipitation, plasma samples were separated on ACQUITY UPLC C_(18) column(2.1 mm×100 mm, 1.7 µm). The mobile phase consisted of water containing 0.2% formic acid and acetonitrile in gradient elution. The negative ions were measured simultaneously in the multi-reaction monitoring(MRM) mode. The pharmacokinetic parameters were calculated and fitted by DAS 2.0. All four components could be detected in the plasma of rats in each group at each time point except the neochlorogenic acid and cryptochlorogenic acid in the Sarcandrae Herba extract group. The guttate pills group showed a significant increase in drug content at each time point. The exposure of the main components of Sarcandrae Herba in blood was effectively increased by PDA-drug loading effect in PDA-Sg Guttate Pills(The AUC_(0-24 h) of neochlorogenic acid, cryptochlorogenic acid, isaziridin and rosmarinic acid reached 2.45, 32.90, 1.54, 4.81 times that of the commercial guttate pills). This study proves the measurability of the above-mentioned multi-component in vitro-in vivo delivery process. The pharmacokinetic study has shown that PDA-Sg Guttate Pills can effectively delay the elimination time and improve the bioavailability of the four components, which can provide theoretical data for the production of the drug.

Acupoint nanocomposite hydrogel for simulation of acupuncture and targeted delivery of triptolide against rheumatoid arthritis.

BACKGROUND: Attenuating inflammatory response and relieving pain are two therapeutic therapeutical goals for rheumatoid arthritis (RA). Anti-inflammatory and analgesic drugs are often associated with many adverse effects due to nonspecific distribution. New drug delivery systems with practical targeting ability and other complementary strategies urgently need to be explored. To achieve this goal, an acupoint drug delivery system that can target deliver anti-inflammatory drugs and simulate acupuncture in relieving pain was constructed, which can co-deliver triptolide (TP) and 2-chloro-N (6)-cyclopentyl adenosine (CCPA). RESULTS: We have successfully demonstrated that acupoint nanocomposite hydrogel composed of TP-Human serum album nanoparticles (TP@HSA NPs) and CCPA could effectively treat RA. The result shows that CCPA-Gel can enhance analgesic effects specifically at the acupoint, while the mechanical and thermal pain threshold was 4.9 and 1.6 times compared with non-acupoint, respectively, and the nanocomposite gel further enhanced. Otherwise, the combination of acupoint and nanocomposite hydrogel exerted synergetic improvement of inflammation, bone erosion, and reduction of systemic toxicity. Furthermore, it could regulate inflammatory factors and restore the balance of Th17/Treg cells, which provided a novel and effective treatment strategy for RA. Interestingly, acupoint administration could improve the accumulation of the designed nanomedicine in arthritic paws (13.5% higher than those in non-acupoint at 48 h), which may explain the better therapeutic efficiency and low toxicity. CONCLUSION: This novel therapeutic approach-acupoint nanocomposite hydrogel, builds a bridge between acupuncture and drugs which sheds light on the combination of traditional and modern medicine.