Search

Ursolic acid is widely used as an effective anticancer drug for the treatment of various cancers. However, its poor water solubility, short circulation time in vivo, and lack of targeting have made it a burden for clinical applications. We report a self-assembled folate-modified pectin nanoparticle for loading ursolic acid (HCPT@F-Pt-PU NPs) and embed the anticancer drug hydroxycamptothecin to achieve synergistic treatment with ursolic acid. In addition, the galactose residue of the pectin molecule can be recognized by the asialoglycoprotein receptor on the surface of the liver cancer cell, promoting the rapid penetration and release of HCPT@F-Pt-PU NPs intracellularly. In particular, the introduction of multiarm polyethylene glycol can improve the uniformity (106 nm) and concealment of the nanoparticles and avoid the early release of the drug or the toxicity to normal cells. HCPT@F-Pt-PU NPs have a high drug loading (7.27 wt %) and embedding efficiency (19.84 wt %) and continuous circulation up to 80 h, leading to more apoptosis (91.61%). HCPT@F-Pt-PU NP intracellular drug delivery will be a promising strategy.

Pine wilt disease is a major forestry quarantine disease caused by pinewood nematode and spread by the vector insect Monochamus alternatus (MA), which has brought destructive harm to pine trees. Av...

Carboxylated cellulose nanocrystals (CCNs), as one of nanocellulose are promising hydrophilic biomass materials for drug delivery. In this work, a series of amphiphilic carboxylated cellulose-graft-Poly(L-lactide) (CC-g-PLLA) copolymers were synthesized via ring-opening polymerization (ROP) method. The copolymers were characterized by 1H-NMR, FT-IR, WXRD and TGA, and their solubility in organic solvents was improved. Then, these amphiphilic copolymers were self-assembled into nanoparticles for delivery of anticancer drug oleanolic acid (OA). The copolymer (DSPLLA 2.03) nanoparticles displayed the smallest size (196.82 ± 9.14 nm) and the highest drug loading efficiency (24.76 ± 0.58%). The nanoparticles exhibited a spherical shape, well water solubility of OA (16.9 mg/mL) and a prolonged drug release (120 h). In vitro and In vivo study indicated that the nanoparticles maintained cytotoxicity to 4T1 cells and MCF-7 cells and displayed high antitumor efficiency. The amphiphilic CC-g-PLLA copolymer nanoparticles provide a novel platform for drug delivery.

In order to face the increasing demand of laccase with high stability and high performance, laccase was chemically modified by acid anhydride, and copper ion (Ⅱ) was coordinated with the hetero atom of the modified laccase to obtain the nanoflower biocatalyst. The effects of different reaction time, laccase concentration and copper sulfate concentration on the formation of nanoflowers were investigated in detail. Compared to free laccase, the enzyme activity, pH stability and thermal stability of nanoflowers increased by 165%, 375% and 430%, respectively. Furthermore, the catalytic properties of our nanoflower biocatalysts were investigated by catalyzing the synthesis of viniferin. The results showed that a higher yield of 45.0% was obtained in shorter period of time than that of the free laccase (21.6%), and the product was single without other by-products. What’s more, nanoflower biocatalyst exhibited excellent storage stability, repeatability and reproducibility in cycle operation. We believed that this study provided a feasible and efficient biocatalytic method for conversion of resveratrol to viniferin. These preliminary results indicated that nanoflowers would have great potential for application in biotransformation and biocatalysis.

Dihydroartemisinin (DHA) as an effective anticancer drug is being concerned owing to the excellent efficacy, but the poor solubility and premature release confine the clinical application. Construction of a satisfied DHA-loaded delivery system with targeted recognition and specific controlled release brings opportunities and challenges, which can be triggered through an endogenous stimulus. In this work, we designed a traceable and dual-targeted DHA-loaded nanocarrier by taking advantage of the highly expression of pectin with galactose residues to asialoglycoprotein receptors on the surface of liver, as well as the highly expression of folic acid (FA) to folic acid receptors. Folic acid modified pectin was coupled with DHA-loaded eight-arm polyethylene glycol conjugates to prepare folic acid-pectin-eight-arm polyethylene glycol-dihydroartemisinin prodrugs (FA-Pectin-8armPEG-DHA), and then embedded hydroxycamptothecin by the self-assembly of hydrophobic drugs and hydrophilic carriers to prepare folic acid...

Background: Pests affect the sustainable development of agriculture and forestry, and seriously threaten food safety and ecological health, the research for efficient and green control measures never stop. Pesticides are currently the most effective means to control pests and ensure food supplies. However, the various drawbacks of traditional pesticide formulations make the utilization low, and most of active ingredients flow into the air, groundwater and soil, destroying the environment. In this research, a novel nano pesticide formulation was synthesized to improve the utilization, with control release performance and anti-photolysis especially. CuBTC, a metal organic framework (MOF) material, was designed as carrier to absorb avermectin (AVM), a commonly used pesticide in agriculture and forestry, to prepare nano pesticide. Results: The prepared AVM@CuBTC had slow release properties, could be released continuously for about 120 h, and the cumulative release exceed 91.5%, and had a more stable release process under different acid-base conditions. The particle size of AVM@CuBTC was about 450 nm, and the loading efficiency reached 38%. The AVM@CuBTC nano pesticide could protect AVM from photolysis, and the amount of degradation was reduced by 50.7% after 5 d treatment. In addition, the particles AVM@FITC@CuBTC were prepared by labeling with fluorescein isothiocyanate (FITC) to research the distribution on larval epidermis, to clarify the coverage, adhesion and permeability of AVM@CuBTC. Finally, the cytotoxicity and contact toxicity of AVM@CuBTC was compared with free AVM, the cytotoxicity and contact toxicity increased by 42.4% and 39.6%, respectively. Conclusion: The cytotoxicity and contact toxicity of AVM are the key factors for the control of pests. Applying AVM@CuBTC to the prevention and control of agricultural and forestry pests is of great significance to the reduction of pesticides and environmental friendliness.

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.

To face the growing demand of polymeric nanoparticles with biocompatibility and a drug release profile, in this work, a novel carboxymethylcellulose-based pH and redox dual-responsive polymeric nanoparticle, carboxymethyl cellulose-dithiopropionate hydrazide-8arm-polyethylene glycol-pterostilbene/10-hydroxy camptothecin (CTPP/HCPT), was prepared for efficient drug codelivery. These well-dispersed CTPP/HCPT NPs were prepared with a dimension of around 144 nm and exhibited high binary drug loading capacity and good biocompatibility. The biggest advantage of this design is that these nanoparticles can rapidly release the drug payload responding to intracellular acidic or reductive stimuli, while maintaining sufficient stability under normal physiological conditions. The in vitro drug release study revealed that the HCPT payload released from nanoparticles in a weakly acidic environment with 10 mM reductive glutathione was about 74.8%, which was 3.8-fold higher than under normal physiological conditions (∼19.6%). Further in vitro and in vivo investigation demonstrated that such dual-responsive CTPP/HCPT NPs could potently kill cancer cells and suppress tumor growth with lower adverse effects. All these results suggested that CTPP/HCPT NPs were suitable as potential and effective candidates for cancer therapy.

Background Trunk-boring pests (TBPs) are an important type of forest pest, TBPs not only feed on the branches and trunks of trees, but also spread quarantine diseases in forests. However, because the larvae of TBPs live inside the trunk and are well concealed, prevention and control are difficult. The lack of effective control methods leads to the death of many trees in forests. In this study, a novel nanopesticide featuring high bioactivity and slow-release properties was developed to control TBPs. Thiacloprid (THI), which is commonly used to control Coleoptera species, was used as a model pesticide. Results The oleophobic properties of bovine serum albumin (BSA) were exploited to encapsulate the hydrophobic pesticide THI by self-assembly, and the size of the obtained nanoparticles, THI@BSA·NPs, was approximately 23 nm. The loading efficiency reached 70.4%, and THI@BSA·NPs could be released continuously for over 15 days, with the cumulative release reaching 93.5%. The fluorescein isothiocyanate (FITC)-labeled nanoparticles were evenly distributed in the digestive tract and body surface of a typical TBPs, M. alternatus, and the stomach and contact toxicities increased by 33.7% and 25.9%, respectively, compared with those of free THI. Furthermore, the results showed that the transport efficiency of THI@BSA·NPs was highest at a concentration of 50 μg/mL, and the THI@BSA·NPs content in the trunk, from to lower to higher layers, was 8.8, 8.2, 7.6, and 5.8 μg/g. At the same time, THI@BSA·NPs also exhibited high transport efficiency in dead trees. Conclusion The transport efficiency and toxicity of the active ingredients are the key factors for the control of TBPs. This work provided idea for the application of biological delivery system encapsulated hydrophobic pesticides. The novel self-assembled THI@BSA·NPs have promising potential for sustainable control of TBPs.