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Lipid nanoparticles (LNPs) can be designed to potentiate cancer immunotherapy by promoting their uptake by antigen-presenting cells, stimulating the maturation of these cells and modulating the activity of adjuvants. Here we report an LNP-screening method for the optimization of the type of helper lipid and of lipid-component ratios to enhance the delivery of tumour-antigen-encoding mRNA to dendritic cells and their immune-activation profile towards enhanced antitumour activity. The method involves screening for LNPs that enhance the maturation of bone-marrow-derived dendritic cells and antigen presentation in vitro, followed by assessing immune activation and tumour-growth suppression in a mouse model of melanoma after subcutaneous or intramuscular delivery of the LNPs. We found that the most potent antitumour activity, especially when combined with immune checkpoint inhibitors, resulted from a coordinated attack by T cells and NK cells, triggered by LNPs that elicited strong immune activity in both type-1 and type-2 T helper cells. Our findings highlight the importance of optimizing the LNP composition of mRNA-based cancer vaccines to tailor antigen-specific immune-activation profiles., (© 2023. The Author(s), under exclusive licence to Springer Nature Limited.)

Background: Micelles as drug carriers are characterized by their inherent instability due to the weak physical interactions that facilitate the self-assembly of amphiphilic block copolymers. As one of the strong physical interactions, the stereocomplexation between the equal molar of enantiomeric polylactides, i.e., the poly(L-lactide) (PLLA) and poly(D-lactide) (PDLA), may be harnessed to obtain micelles with enhanced stability and drug loading capacity and consequent sustained release., Aims/methods: In this paper, stereocomplexed micelles gama-PGA-g-PLA micelles) were fabricated from the stereocomplexation between poly(gama-glutamic acid)-graft-PLLA gama-PGA-g-PLA) and poly(gamaglutamic acid)-graft-PDLA gama-PGA-g-PLA). These stereocomplexed micelles exhibited a lower CMC than the corresponding enantiomeric micelles., Result: Furthermore, they showed higher drug loading content and drug loading efficiency in addition to more sustained drug release profile in vitro. In vivo imaging confirmed that the DiR-encapsulated stereocomplexed gama-PGA-g-PLA micelles can deliver anti-cancer drug to tumors with enhanced tissue penetration. Overall, gama-PGA-g-PLA micelles exhibited greater anti-cancer effects as compared with the free drug and the stereocomplexation may be a promising strategy for fabrication of anti-cancer drug carriers with significantly enhanced efficacy., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.)

Viruses have evolved to be outstandingly efficient at gene delivery, but their use as vectors is limited by safety risks. Inspired by the structure of viruses, we constructed a virus-mimicking vector (denoted as TR4@siRNA@Tf NCs) with virus-like architecture and infection properties. Composed of a hydrophilic peptide, an aggregation-induced emission (AIE) luminogen, and a lipophilic tail, TR4 imitates the viral capsid and endows the vector with AIE properties as well as efficient siRNA compaction. The outer glycoprotein transferrin (Tf) mimics the viral envelope protein and endows the vector with reduced cytotoxicity as well as enhanced targeting capability. Because of the strong interaction between Tf and transferrin receptors on the cell surface, the Tf coating can accelerate the intracellular release of siRNA into the cytosol. Tf and TR4 are eventually cycled back to the cell membrane. Our results confirmed that the constructed siRNA@TR4@Tf NCs show a high siRNA silencing efficiency of 85% with significantly reduced cytotoxicity. These NCs have comparable transfection ability to natural viruses while avoiding the toxicity issues associated with typical nonviral vectors. Therefore, this proposed virus-like siRNA vector, which integrates the advantages of both viral and nonviral vectors, should find many potential applications in gene therapy.

Summary: This study investigated the formation and properties of mung bean‐resistant starch nanoparticles. The mung bean amylose content increased from 56.86% to 68.29% with the ultrasonic time increasing. The particle size, X‐ray diffraction and in vitro digestion of mung bean‐resistant starch nanoparticles were studied. All the nanoparticles presented V‐type crystalline structure, which indicated the formation of starch‐curcumin complex. Results of particle size showed that size distribution curve of resistant starch nanoparticles with ultrasonic treatment of 2 min had only one peak and it was narrower than others. According to the in vitro digestion results, digestibility of resistant starch nanoparticles increased compared with that of native starch, the reason was because of the formation of starch‐curcumin complex. This study provides a method to prepare resistant starch nanoparticles with a higher resistant starch content and could improve the stability and bioavailability of curcumin. [ABSTRACT FROM AUTHOR]

Postmodification methods are effective tools in preparing functional polymers, and novel end‐group reactions have attracted much attention from researchers for postmodification applications. Here, a new high‐efficiency postmodification method is proposed, which can change bromine‐containing polymers to functional polymers in one step. Phenol, 1‐hydroxynaphthalene, and 4‐(2‐phenyldiazenyl)‐phenol (AzoOH) are successfully grafted onto the polymeric branch chain of bromine‐containing polymers, i.e., homopolymer, bromoethyl methyl acrylate, (pBMEA) and amphiphilic block copolymer p(BMEA)‐b‐p(mPEG), with a high grafting rate that is near 100%. Also, the micelles of the postmodified amphiphilic block copolymer p(BMEA‐Azo)‐b‐p(mPEG) are broken up under ultraviolet irradiation. The proposed method can be used as a platform to prepare a variety of stimuli‐responsive polymeric nanoparticles. [ABSTRACT FROM AUTHOR]

Abstract Under oil droplet supply a simplified elastohydrodynamic lubrication (EHL) model incorporating slide-roll ratios has been established, and the lubrication behavior of one oil droplet passing through the contact zone was numerically simulated. The results showed that sliding elongates the oil droplet and the oil reservoir at the inlet, and thus the effective lubrication can be enhanced. However if the slide-roll ratio is too large lubrication failure may occur. The effect of the slide-roll ratio is markedly influenced by lubrication parameters η 0 u e , and the increase of η 0 u e leads to a decrease in the effective lubrication time. Heavy load reduces the effective lubrication time. Highlights • Considering the sliding effect, a simplified elastohydrodynamic lubrication model has been established under one oil droplet supply. • Results show that sliding elongates the oil droplet and thus the effective lubrication can be enhanced. • The effect of the slide-roll ratio is markedly influenced by lubrication parameters η 0 u e and load. • The reasonable choice of oil droplet volume can prevent lubrication failure under relatively large slide-roll ratio. [ABSTRACT FROM AUTHOR]

The native corn starch and corn amylose were used to prepared starch nanoparticles through two kinds of nanoprecipitation methods. The mainly property of these starch nanoparticles was the crystalline property, at the same time, the particle size, morphology, FT-IR spectra and contact angle of the starch nanoparticles were also investigated. Results showed that the mean size values of native corn starch nanoparticles were smaller than that of corn amylose nanoparticles prepared by the two methods. The nanoprecipitation methods had no significant difference on crystalline structure for all the starch nanoparticles, while the corn amylose nanoparticles prepared by dropping ethanol into the amylose paste had a higher crystallinity of 52.49%, and the water contact angle of which increased to 38.72° than that of corn amylose. Pickering emulsions stabilized by the above amylose nanoparticles showed a more concentrated particle size distribution and the nanoparticles could be well dispersed on the surface of the oil droplets. The results of this study demonstrated that corn amylose nanoparticles prepared by dropping ethanol into the amylose paste had a potential application in stabilizing Pickering emulsions. [ABSTRACT FROM AUTHOR]

Inspired by the antifouling property of superhydrophobic surfaces of creatures, developing hybrid materials by loading antibacterial agents of silver nanoparticles on the superhydrophobic stainless-steel meshes, has been successfully achieved by the combination of double-potential deposition and in-situ polymerization grafting method. This study systematically investigated the effects of influencing factors on the Ag nanoparticles topography in the electrodeposition process, including nucleation potential, nucleation time, growth potential and growth time etc. According to the results of the inhibition zone test, from the comparative analysis of the antibacterial effect of the prepared specimens under different deposition parameters, it can be seen that the growth time during the double-potential deposition process had a relatively significant effect. Meanwhile, the presence of Ag nanoparticles is favor to improve the polymerization grafting of PDA@ODA compounds, which exhibited a superhydrophobic state with WCA of 160.6° and SA of 3°. No matter in static or dynamic culture process, the superhydrophobic surfaces were beneficial for reducing bacterial adhesion, ascribed to the superhydrophobic and antibacterial performance associated with the synergistic effect of organic PDA@ODA compounds and inorganic Ag nanoparticles. Moreover, the superhydrophobic stainless-steel mesh have good long-term stability and mechanical stability, which is favor to expand the application scope and working life. Unlabelled Image • Stainless-steel meshes were prepared by double-potential deposition and modification. • The superhydrophobic surfaces were beneficial for reducing bacterial adhesion. • The surface presented superhydrophobicity, antibacterial property and stability. [ABSTRACT FROM AUTHOR]

Targeted drug delivery systems (TDDSs) provide a promising approach to overcome the side effect of traditional chemotherapy by specific tumor targeting and drug release. Hyaluronan (HA), as a selective CD44 targeting group, has been widely used in TDDSs for chemotherapy. However, different molecular weight HAs would demonstrate different binding ability to CD44, which may result in different therapeutic effects. Herein, a silica/hydroxyapatite (MSNs/HAP) hybrid carrier loaded with anticancer drug doxorubicin (DOX) (DOX@MSNs/HAP) is fabricated. HA and oligo HA (oHA) are coated onto the nanoparticles (HA‐DOX@MSNs/HAP, oHA‐DOX@MSNs/HAP), respectively, to investigate their performance in tumor targeting ability. oHA‐DOX@MSNs/HAP shows much higher efficiency cellular uptake and drug release in tumor regions due to more effective CD44 targeting of oHA. Thus, the anticancer effect of oHA‐DOX@MSNs/HAP is significantly enhanced compared to HA‐DOX@MSNs/HAP, as demonstrated in a tumor‐bearing mouse model. This study may enable the rational design of nanodrug systems for future tumor‐targeted chemotherapy. [ABSTRACT FROM AUTHOR]

Jerusalem artichoke is an important natural matrix for inulin production. In this experiment, response surface methodology (RSM) was employed to optimize the spray-drying parameters in order to determine the maximal inulin yield. For this study, three independent variables (heating temperature (Tª, 110–120 °C), creep speed (V, 18–22 rpm) and pressure (P, 0.02–0.04 MPa)) were used in the experimental design. Using the Box–Behnken design, the optimal parameters obtained were: drying temperature 114.6 °C, creep speed 20.02 rpm, and pressure: 0.03 MPa. The inulin yield, water content and particle size of inulin obtained by spray-drying and freeze-drying were compared. In this regard, the spray-dried inulin consisted of a white powder having a fine particle size, and the freeze-dried inulin had a pale-yellow fluffy floc. On the other hand, the drying methods had a great influence on the appearance and internal structure of inulin powder, since the spray-dried inulin had a complete and uniform shape and size, whereas the freeze-dried inulin had a flocculated sheet structure. The analysis showed that the spray-drying led to a higher inulin yield, lower water content and better surface structure than freeze-drying. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the storage stability and functional properties of different sizes of tea polysaccharides, and explore the relationship between sizes and digestive properties, so as to provide reference for the subsequent utilization of tea polysaccharides. In this study, TPS-NPs of about 200 nm and 400 nm were prepared by electrostatic interaction with TPS and EDTA ratios of 6:1 and 100:1, respectively. The structural properties of TPS-NPs were investigated by a series of characterization analyses. The results showed that the major functional groups of TPS-NPs did not change significantly with particle size, but the C O stretching vibrations in the methylated carboxyl group were more pronounced. However, their DPPH free radical scavenging ability and antioxidant activity of TPS were decreased in vitro because of the destruction of the apparent structure of tea polysaccharides nanoparticles during preparation. Stability measurements revealed that TPS-NPs have high storage, temperature, pH and ionic concentration stability, especially for TPS-NPs with a particle size of 200 nm. The digestibility of 400 nm TPS-NPs was improved to 3.89% compared to TPS. The results showed that the TPS-NPs has excellent stability and digestibility, which contributed to the development of TPS applications in the food industry and related products. • The tea polysaccharide nanoparticles at 200 nm and 400 nm were stably prepared by the electrostatic interaction. • The structural of TPS-NPs and TPS were studied by UV, FT-IR, Roman spectra and SEM. • TPS-NPs had higher storage stability under a variety of conditions, including ionic strength, pH and temperature. [ABSTRACT FROM AUTHOR]