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Dietary selenium (Se) supplementation has recently received increasing attention; however, Selenium nanoparticles (SeNPs) exhibit poor stability and tend to aggregate in aqueous solution. Therefore, enhancing the stability of SeNPs and their effective delivery to plants remain challenging. In this study, sodium alginate (SA) and lysozyme (LZ) were reacted via the wet-heat Maillard reaction (MR) to obtain amphiphilic alginate-based polymers (SA-LZ). Alkyl glycosides (APG) were introduced into SA-LZ to enhance the deposition of SeNPs in leaves. Thus, a renewable and degradable polysaccharide-based material (SA-LZ/APG) loaded with Se formed an amphiphilic alginate-based-based shell with a Se core. Notably, the encapsulation of SeNPs into a polysaccharide base (SA-LZ/APG) increased the stabilization of SeNPs and resulted in orange-red, zero-valent, monoclinic and spherical SeNPs with a mean diameter of approximately 43.0 nm. In addition, SA-LZ/APG-SeNPs reduced the interfacial tension of plant leaves and increased the Se content of plants compared to the blank group. In vitro studies have reported that SA-LZ/APG-SeNPs and SA-LZ-SeNPs have significantly better clearance of DDPH and ABTS than that of APG-SeNPs. Thus, we believe that SA-LZ/APG is a promising smart delivery system that can synergistically enhance the stability of SeNPs in aqueous solutions and improve the bioavailability of Se nutrient solutions., Competing Interests: Declaration of competing interest The authors declare no competing financial interest., (Copyright © 2024. Published by Elsevier B.V.)

The oil/water separation of oil-in-seawater emulsion plays an important role in resource recovery and ecological environment restoration. In this work, oil-in-seawater Pickering emulsion in seawater with high salinity was stabilized by Fe 3+ ions and amphiphilic alginate (AM-Alg), subsequently destabilized by UV light for efficient oil/water separation. Initially, AM-Alg exhibited high viscoelasticity at the oil-water interface, which was confirmed by Quartz crystal microbalance. The addition of Fe 3+ caused the aggregation of AM-Alg at the oil-water interface and improved the formation of the three-dimensional interpenetrating network structure. When Fe 3+ was at 0.1 mol/dm 3 , the oil-in-seawater Pickering emulsion had the best stability, and also the fastest demulsification speed under UV light. Moreover, the photochemical redox reaction rate and the conversion rate of Fe 3+ were the highest. This photo demulsification technology is expected to become a new method of dealing with marine oil spills., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

The development of an eco-friendly nanopesticide formulation can alleviate the problems of low pesticide utilization and environmental pollution. However, the development of green nanopesticide carriers with ideal physical properties and specific bioavailability is still a challenging task at present. In this study, we propose a novel binary additive pesticide carrier system that is a functional polysaccharide-based polymer/surfactant (Alg-DA/APG) to improve the deposition and retention of pesticide droplets. The self-assembled micelle morphology of Alg-DA/APG and its effect on the apparent viscosity were investigated by transmission electron microscopy (TEM) and a Discovery HR-2 rotational rheometer. Surface tension was carried out to investigate the surface activity and critical micelle concentration (CMC) of Alg-DA/APG. The drop impacting experiments exhibited superior antisplash performance of Alg-DA/APG. Furthermore, a binary additive was used as the carrier material and loaded acetamiprid to prepare nanopesticide formulation Ace@Alg-DA/APG. The encapsulation efficiency (EE) and acetamiprid release behavior from Ace@Alg-DA/APG were also studied. Moreover, the dynamic contact angle (DCA) and retention experiment showed that the DCA and wetting radius at 600 s were, respectively, 6.8 ± 2.39° and 4.044 ± 0.0662 mm for the Ace@0.05 wt % Alg-DA/0.05 wt % APG on the banana foliage surface, and its retention rates on foliage surface were up to 74.80% after washing. The novel binary additive as a nanopesticide carrier has the potential to alleviate the problems of low pesticide utilization and environmental pollution in the future.

Soil aggregation plays an important role in agricultural production activities. However, the structure of soil aggregation is destroyed by the natural environment and unreasonable farming management, resulting in the loss of water, fertilizers and pesticides in soil. At present, hydrogels have been widely reported to promote the formation of soil aggregation. In this paper, amphiphilic calcium alginate (ASA/Ca 2+ ) was applied to promote the formation of soil aggregation and enhance pesticide retention. Initially, an ASA was obtained through the one-pot Ugi condensation (a four-component green chemical reaction). Then, ASA/Ca 2+ hydrogel is prepared by Ca 2+ cross-linking. The formation of soil aggregation was determined through the Turbiscan Lab Expert stability analyzer, Confocal Laser Scanning Microscope (CLSM), and Transmission Electron Microscope (TEM). And the effect of soil aggregation on acetamiprid environmental behavior was investigated by adsorption kinetics, adsorption isotherms, and leaching. The results shown that the three-dimensional network structure of ASA/Ca 2+ hydrogel can promote the formation of soil aggregation. Aggregate durability index (ADI) was 0.55 in the presence of ASA/Ca 2+ hydrogel, indicating that amphiphilic hydrogel can enhance the stability of soil aggregation. The adsorbing capacity of acetamiprid was 1.58 times higher than pure soil, and the release of acetamiprid only about 20% in the presence of ASA/Ca 2+ hydrogel. These results would be helpful for the formation of soil aggregation and pesticides adsorption on soil aggregation. Thus, ASA/Ca 2+ hydrogel is likely to improve soil quality, simultaneously it can minimize the mobility of pesticides in the agricultural system., (Copyright © 2021. Published by Elsevier B.V.)

Alginate has been widely applied in various biological systems due to its great biocompatibility. Endowing it fluorescent imaging would make people to further understand its complex structure, process and mechanism. In this work, amphiphilic alginate conjugated with aggregation-induced emission (AIE) moiety fluorescent polymer was successfully fabricated through the Ugi one-pot condensation. The synthetic polymer particles were fully evaluated by various characterizations including 1 H NMR, FTIR, fluorescent spectroscopies, and transmission electron microscopy (TEM). These amphiphilic alginate particles showed great multicolor fluorescence emission in both solid and solution states. The corresponding biological evaluation results confirmed that the fluorescent biopolymer showed excellent biocompatibility and desirable bioimaging property. Particularly, the leaf stomata were directly visualized using the amphiphilic AIE-active alginate biopolymer. Furthermore, the alginate-based polymer can also be employed as the drug carrier for hydrophobic curcumin. These results indicated that our synthetic AIE-active alginate particles might provide great potential for the further utilization of alginate in the understanding of various relative biological systems., (Copyright © 2021. Published by Elsevier B.V.)

The effects of amphiphilic O/W emulsions, stabilized by the alkyl polyglycoside (APG) or cholesterol-grafted sodium alginate (CSAD)/APG systems, on lambda-cyhalothrin adsorption/desorption mechanisms on natural soil minerals (i.e., illite and kaolinite) were investigated. Sorption and desorption of lambda-cyhalothrin onto soil minerals was studied via batch equilibration to give insight into the adsorption equilibrium, kinetics, and thermodynamics of lambda-cyhalothrin adsorption onto minerals. The results indicate the following: (i) The adsorption processes for the APG system and CSAD/APG system include: rapid adsorption, slow adsorption, and adsorption equilibrium. The adsorption kinetics of pesticide on illite and kaolinite are in accordance with the Ho and McKay model, and the adsorption isotherm conforms to the Freundlich model. In addition, the adsorption processes of pesticide for the two systems on minerals were spontaneous and feasible (ΔG 0  < 0), endothermic (ΔH 0  > 0), and mainly involved chemical bonding (ΔH 0  > 60). (ii) The equilibrium adsorption percentages of the pesticide on illite for the APG system and CSAD/APG system were 42.4% and 64.8%, and the corresponding equilibrium adsorption percentages on kaolinite were 40.8% and 61.8%, respectively. Moreover, the pesticide adsorption rate K 2-CSAD/APG was faster than K 2-APG , and its adsorption capacity K f-CSAD/APG was greater than K f-APG . Meanwhile, the pesticide desorption K fd in the CSAD/APG system was smaller than that in the APG system. As a result, this eco-friendly O/W emulsion based on amphiphilic sodium alginate derivatives might provide a green pesticide formulation, since it could reduce the amount of lambda-cyhalothrin entering aquatic systems to threaten non-target fish and invertebrate species., (Copyright © 2018. Published by Elsevier B.V.)

In this study, cholesteryl-grafted sodium alginate derivatives (CSAD) with different molecular weights were synthesized by esterification. The structure of CSAD was confirmed by FT-IR and 1 H NMR spectrometers. The effects of pH and CSAD polymer concentration on the self-assembled behavior and particle size of CSAD were investigated by fluorescence measurement (FM) and dynamic light scattering (DLS). In the presence of Ca 2+ , the cholesteryl-grafted sodium alginate derivative was used for fabricating self-assembled nanoparticles that can effectively encapsulate the drug acetamiprid. The drug-loaded nanoparticles were characterized by transmission electron microscopy (TEM). The encapsulation efficiency (EE) and acetamiprid drug release behavior from the nanoparticles were also studied. The results reveal that CSAD self-assembled nanoparticles had a diameter of 100nm and were nonaggregated in aqueous media; Moreover, the encapsulation efficiency and the release behavior of nanoparticles were influenced by the MW of CSAD. The mechanism of acetamiprid release was found to vary from non-Fickian (anomalous) to Fickian transport with a decrease in the molecular weight of CSAD., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Amphiphilic polymers that form self-assembled structures in aqueous media have been investigated and used for the diagnosis and therapy of various diseases, including cancer. In our work, a series of environment-sensitive hydrophobic alginates (Ugi-Alg) with various weight-average molecular mass values (Mw~6.7×10 5 -6.7×10 4 g/mol) were synthesized via Ugi reaction. The structure of Ugi-Alg was characterized by 1 HNMR spectrometer. The electrostatic self-assembly of different molecular weight (Mw) and composition (M/G ratio) of Ugi-Alg chain under various Na + concentrations, was investigated by dynamic light scattering, electron spin resonance experiments, and transmission electron microscopy. Result showed that by comparing to other Ugi-Alg, the mid-Mw Ugi-Alg (Mw~2.8×10 5 g/mol) could form stable and homogeneous nanoparticles in low Na + concentration solution. However, G/M values exerted no obvious effect on nanoparticles structure. Additionally, steady-shear flow, thixotropy and dynamical viscoelasticity tests were performed to characterize the rheological behavior of Ugi-Alg aqueous solutions as influenced by Mw and M/G ratio. All of the samples exhibited a non-Newtonian shear-thinning behavior above a critical shear rate (γ̇ c2 ). The greater the Mw, the more sensitive the temperature-dependent behavior will be. The upward-downward rheograms showed that all of the systems evaluated in this study displayed a hysteresis loop, indicating a strong thixotropic behavior, and the thixotropic of mid-Mw Ugi-Alg was the strongest. The dynamical viscoelastic properties were characterized by oscillatory frequency sweep, revealing the gel-like viscoelastic behavior of mid-low Ugi-Alg and the fluid-like viscoelastic behavior of high-Mw Ugi-Alg., (Copyright © 2016. Published by Elsevier B.V.)

In this research, the systematic evaluation of fundamental properties of the alginate derivative (Ugi-Alg) synthesized by the Ugi reaction is presented. The structure of Ugi-Alg with the degree of substitution of 23.24% was confirmed by FT-IR and (1)H NMR spectrometers. The X-ray diffraction (XRD) results indicate the amorphous structure and the crystal structure change of Ugi-Alg, which is possibly ascribed to the destruction of inter- and intra-molecular hydrogen bonding interactions during the Ugi reaction. From thermal gravimetric analysis (TGA) and fluorescence spectrophotometer, Ugi-Alg shows high thermal stability and good amphiphilic functionality with the critical aggregation concentration of 0.07 g/L in 0.15 mol/L aqueous NaCl solution. Transmission electron microscope (TEM) image and dynamic light scattering (DLS) reveal that stable Ugi-Alg self-aggregated micelle with the average size of 162.3 nm and ζ potential at about -31.7 mV could form in the aqueous media, which presents tremendous potential in pharmacology and tissue engineering., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

As a kind of novel hydrophobic drug carrier materials, the drug-loaded nanofibers were successfully fabricated using amphiphilic alginate derivative (AAD) and poly (vinyl alcohol) (PVA) by electrospinning method. The AAD was synthesized by amide linkage attachment of octylamine onto the carboxylic group of alginate, which was characterized by the means of elemental analysis, FT-IR spectrometer, H NMR spectrometer and fluorescence measurement. Experimental results showed the amidation of alginate was successful, in which the degree of modification was 0.27 and the critical aggregation concentration in 0.15 mol/L aqueous NaCl solution was 0.43 mg/mL. The octyl groups of AAD could effectively make alginate chains flexible and enhance chain entanglements through the hydrophobic interactions between octyl groups. In contrast to sodium alginate (SA)/PVA blend solutions, AAD/PVA blend solutions showed more excellent electrospinnability. Additionally, the different volume ratios of SA or AAD to PVA played an important role in the formation and morphology of the electrospun blend nanofibers. Although the amidation of alginate could not fundamentally alter the spinnability of alginate, the content of alginate in the blend nanofibers was appropriately increased. The new generated drug-loaded AAD/PVA (20/80) blend nanofibers exhibited relatively continuous and uniform nanofibers with the average diameter of 191.72 nm. Compared to the drug-loaded SA/PVA (20/80) blend nanofibers, the drug-loaded AAD/PVA (20/80) blend nanofibers presented a sustained release performance with the slow release of about 76 % λ-cyhalothrin during the initial period of 10 h. [ABSTRACT FROM AUTHOR]

High quantum yield polysaccharide-based materials are significative for the dynamic anti-counterfeiting, while that are limited by weak fluorescence. However, natural polysaccharides with weak fluorescence are not suitable for anti-counterfeiting. Herein, alginate derivatives (SA-PBA) exhibiting aggregation-induced emission with high-quantum yields were synthesized by grafting phenylboronic acid (PBA) onto a sodium alginate (SA) chain. As the concentration increases, polymer assembly can be induced to form more compact soft colloidal aggregates, which enhances the fluorescence properties of alginate derivatives by introducing B ← N coordination bonds in the hydrophobic microregions. Interestingly, the clustered aggregates of SA-PBA can be dynamically controlled by pH, realizing the reversible adjustment of fluorescence. The corresponding mechanism is revealed by the combination of coarse-grained simulations and experiments. It is found that SA-PBA uses a hydrophobic driving force and hydrogen bond interaction to self-assemble in an aqueous solution and promote fluorescence emission. Moreover, the fluorescence quantum yield of SA-PBA can reach 14.4 % and can be reversibly altered by tuning soft colloidal microstructures. Therefore, a reversible information encryption system of SA-PBA is developed for anti-counterfeiting. This work shed some light on how to design novel anti-counterfeit materials based on natural polysaccharides and optimize the dynamic fluorescence conditions. [Display omitted] • B ← N coordination bonds reinforce the luminescence of alginate derivatives. • The luminescence intensity of SA-PBA can be dynamically altered by pH. • The combination of CGMD has unveiled the luminescence mechanism. • SA-PBA can be candidates for information storage and anti-counterfeiting. [ABSTRACT FROM AUTHOR]

Polysaccharide-based soft colloidal particles mediated by the dynamic bonding-engineered interfacial self-assembly can regulate the properties of oil-water interfacial films, availing the stability of emulsions under a wide pH range. The amphiphilic phenylboronic alginate soft colloidal particles (Alg-PBA) were designed to stabilize pH-responsive Pickering emulsions (PEs). Combining stability analysis with quartz crystal microbalance and dissipation monitoring (QCM-D), the microstructure and viscoelasticity of Alg-PBA at the oil-water interface were determined. The results showed that PEs stabilized by Alg-PBA due to a thicker and stronger viscoelastic interface film induced by B O bonds and hydrogen bonds. The structure-function relationship of the Alg-PBA emulsifier driven by dynamic bonds was further elaborated at multiple scales by laser scanning microscopy (CLSM) and scanning electron microscopy (SEM). Meanwhile, the microstructure of aerogels templated by emulsion could be tuned by adjusting dynamic bonds, which provides a new idea for polysaccharide soft material engineering. [Display omitted] • Amphiphilic phenylboronic alginate was used to design Pickering emulsions. • Pickering emulsion stability was influenced by interfacial microstructure. • Interfacial microstructure engineered by dynamic bonding was regulated. • The dynamical bonding emulsion soft template controlled aerogel microstructure. [ABSTRACT FROM AUTHOR]

Functional Pickering emulsions that depend on the interparticle interactions hold promise for building template materials. A novel coumarin-grafting alginate-based amphiphilic telechelic macromolecules (ATMs) undergoing photo-dimerization enhanced particle-particle interactions and changed the self-assembly behavior in solutions. The influence of self-organization of polymeric particles on the droplet size, microtopography, interfacial adsorption and viscoelasticity of Pickering emulsions were further determined by multi-scale methodology. Results showed that stronger attractive interparticle interactions of ATMs (post-UV) endowed Pickering emulsion with small droplet size (16.8 μm), low interfacial tension (9.31 mN/m), thick interfacial film, high interfacial viscoelasticity and adsorption mass, and well stability. The high yield stress, outstanding extrudability (n 1 < 1), high structure maintainability, and well shape retention ability, makes them ideal inks for direct 3D printing without any additions. The ATMs provides an increased capacity to produce stable Pickering emulsions with tailoring their interfacial performances and, providing a platform for fabricating and developing alginate-based Pickering emulsion-templated materials. Generalized 3D printing toward Pickering emulsions stabilized by light-induced telechelic alginate-based amphiphilic derivative. [Display omitted] [ABSTRACT FROM AUTHOR]

The development of a green-friendly intelligent drug delivery system with maximum drug utilization is the hot spot in the current era of great health and the grand strategy of protecting the environment. However, the evolution of interface multi-scale structure and the micro-mechanism of drug controlled-release/extended-release in intelligent drug-loading system are still common basic research issues in related application development. Therefore, we innovatively explored the effects of pH and UV on the stability, drug-loading and release behavior of coumarin-based alginate (SA-AMC) emulsion by the scientific research method combination of computer simulation and experimental analysis. The simulation results showed that the shrinkage of SA under acidic condition and the dimerization of AMC at 365 nm UV could improve the stability of the emulsion. Meanwhile, the drug-loading capacity and extended-release effect of the emulsions were closely related to the stability of the emulsions, and the drug molecules could be controlled release under alkaline condition. The experimental results were in good consistent with the simulation results, which indicated that the computational simulation had the excellent fitting effect on the experimental conditions, and could understand the behavior of emulsifier molecules at the micro-scale while providing theoretical guidance for the design and optimization of drug delivery system for drug-loading emulsions. [Display omitted] [ABSTRACT FROM AUTHOR]

Soft emulsifiers with relatively suitable structural controllability are necessarily required for the preparation of multifunctional Pickering emulsions. Herein, a β-cyclodextrin-grafted alginate/azobenzene-functionalized dodecyl (Alg-β-CD/AzoC. 12) polymeric supra-amphiphile was designed based on the host-guest interfacial self-assembly. As compared with Alg-β-CD amphiphilic polymers, the interfacial tension of Alg-β-CD/AzoC12 supra-amphiphilic assemblies reduced from 29.57 mN/m to 0.18 mN/m, indicating the great amphiphilicity derived from Alg-β-CD/AzoC12 supra-amphiphilic assemblies. With the increase of pH, the interfacial microstructures transformed from flocculated structures, spherical structures into deformed structures. Especially, the spherical microstructures with the highest interfacial viscoelasticity and thickness demonstrated the highest emulsifying efficiency due to the steric hindrance mechanism. Moreover, the interfacial elastic modulus of adsorbed layers exhibited ~4 times of that upon the ultraviolet illumination. These results disclosed that the interfacial microstructures could be readily regulated by the tunable amphiphilicity of Alg-β-CD/AzoC12 assemblies, which would be useful for the applications of Pickering emulsions in numerous fields. • Supra-amphiphilic assemblies showed relatively more matched amphiphilicity. • Polymeric alginate moieties increased host-guest interfacial adsorption. • Polymeric host-guest assemblies formed a thicker interfacial film with higher viscoelasticity. • Polymeric supra-amphiphile showed better interfacial structural controllability. [ABSTRACT FROM AUTHOR]