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Context: Lignin has an immense potential for the production of lignin-based functional materials. In this work, effect of 2-chloro-ethyltrimethyl ammonium chloride (AC)-grafted alkali lignin (AL) on the morphologies in water was investigated by dissipative particle dynamics (DPD) simulations. The results showed that AL molecules formed spherical micelles, but the corresponding phenylpropane units of AL were randomly distributed in spherical micelles. However, AC-grafted modification of phenolic hydroxyl groups in AL led to the formation of multilamellar spherical micelles. The formation of multilamellar spherical micelles of AL mainly went through four stages: small clusters, larger aggregates with a core-shell structure, trilaminar, and multilamellar spherical micelles. AL molecules resulted in dimethomorph molecules being randomly distributed in the spherical micelle, while the dimethomorph molecules were perfectly entrapped into the spherical micelles of AC-grafted AL. Various molecular weights of AL had no effect on the formation and size of multilamellar spherical micelles. With increasing the content of AC-grafted AL, small clusters, multilamellar spherical micelles, tube-like, and lamellar aggregates were observed successively. This work highlights the potential of lignin to prepare monodispersed lignin-based functional colloidal spheres., Methods: Coarse-grained beads were performed energy minimization, geometric optimization, NPT ensemble (298 K and 1.0 bar), and NVT ensemble (298 K) calculations. DPD simulations were carried out at 300,000 steps in a 30×30×30 Rc 3 cubic box with Materials Studio 7.0 program., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Recently, cellulose-based stimuli-responsive nanomaterials have received significant attention because of its natural source and biocompatibility. In this study, cellulose-graft-poly(nisopropylacrylamide)-co-2-methyl-acrylic acid 2-carbazol-9-yl-ethyl ester (cellulose-g-(PNIPAAm&PCz)) block polymers were successfully synthesized by homogeneous atom transfer radical polymerization (ATRP) in LiCl/N,N-dimethylacetamide (DMAc) dissolution system. The block polymers showed different properties due to the different PCz content. The block polymer with low PCz content (cellulose-g-(PNIPAAm&PCz)1) was dispersed in water at 25 °C and self-assembled into micelles at 37 °C. On the other hand, the block polymer with high PCz content (cellulose-g-(PNIPAAm&PCz)2) was dissolved in DMF, THF, DMSO firstly, and dialyzed at 25 °C, 37 °C and 60 °C respectively to obtain the micelles. Transmission electron microscopy (TEM) and dynamic light scattering (DLS) indicated that the distribution range of micelles formed by cellulose-g-(PNIPAAm&PCz)1 was narrower than cellulose-g-(PNIPAAm&PCz)2. And the sizes of the micelles formed by cellulose-g-(PNIPAAm&PCz)2 had little difference under different solvents, but became bigger with the temperature increased. The micelles displayed thermo-enhanced fluorescence due to the thermal-driven chain dehydration of the grafted PNIPAAm brushes, which is contrary to the decrease of the fluorescence of the monomer when the temperature increased. The results provided a potential for the application of cellulose-based stimuli-responsive micelles in the field of drug delivery and fluorescent probes., Competing Interests: Declaration of competing interest The authors declare that they have no competing interests., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Patients with cancer suffer from severe side effects and reduced life quality, as chemotherapeutic drugs are cytotoxic toward normal cells as well as toward cancer cells. In recent years, nanoparticles have been explored as targeted drug delivery systems; however, problems such as toxicity and instability prevent their practical application. Here, we report the synthesis of cholesteryl-carboxymethyl xylan (CCMX) via an esterification reaction between the carboxyl group of carboxymethyl xylan and the hydroxyl group of cholesterol to form biocompatible micelles as a vehicle for targeted drugs. With its critical micelle concentration (CMC) depending on the degree of substitution (DS) of cholesteryl and ranging from 0.0024 to 0.017 mg/mL, CCMX could self-assemble and form nanoscale micelles in aqueous media. Taking doxorubicin (DOX) as a model drug, the drug encapsulation efficiency (EE%) of CCMX-3 (DS of 0.35 for cholesteryl) reached 91.3%, and this system exhibited excellent internalization ability, as verified by tumor cellular uptake tests. The results of in vitro cytotoxicity and in vivo antitumor activity tests of nude mice demonstrated that CCMX-3/DOX micelles effectively suppressed the growth of tumor cells by maintaining the cytotoxicity of commercial DOX injection while reducing the toxicity against normal cells and increasing the survival time.

A series of linoleic acid conjugated hydroxyethyl cellulose polymers (HEC-g-LA) were synthesized and characterized. And their solubilities in a variety of solvents were compared. The prepared HEC-g-LA polymers showed typical properties of amphiphilic polymers and were able to self-assemble into spherical nanomicelles in aqueous solution. The micelle sizes and critical micelle concentrations (CMC) were found correlated with the molecular structure of polymers, and were varied in the range of 20-50nm and 1.92-21.76μg/ml, respectively. Furthermore, the hydrophobic active component β-carotene (β-C) was successfully encapsulated into the HEC-g-LA micelles by sonication-dialysis method. The β-C encapsulation efficiency and loading content were found to be as high as 84.67% (w/w) and 4.23%. The results of in vitro release showed that the encapsulated β-C was continuously released from the micelles in phosphate buffered saline (PBS) medium for about 7days. The self-assembled HEC-g-LA nanomicelles are potential nanocarriers of hydrophobic active compounds for functional food applications., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

β-Carotene (β-C) is a well-established natural antioxidant agent, but its poor water-solubility, low chemical stability and low bioavailability limit its application in food, pharmaceuticals and cosmetics industries. Thus it is critical to develop an efficient method to improve the water solubility and stability of β-C. In this research, amphiphilic chitosan-graft-poly (lactide) (CS-g-PLA) copolymer was synthesized via a homogeneous ring-opening polymerization (ROP) in ionic liquid. The obtained CS-g-PLA copolymer was able to self-assemble into about 14 nm micelles in water at low concentration, and β-C loaded micelles (β-C/M) had low β-C degradation after 15 days. The antioxidant properties of the β-C/M were investigated by the 2, 2-diphenyl-1-picrylhydrazyl (DPPH) method and ferric reducing antioxidant power (FRAP) method, respectively. Significantly improved antioxidant activity was observed for β-C/M in compare with free β-C. The aqueous dispersion of β-C/M has potential to be applied in the field of functional food and cosmetics., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

We previously produced a bactericidal filter paper loaded with PAA47-b-PS214 block copolymer micelles containing the biocide triclosan (TCN), using cationic polyacryamide (cPAM) as a binder. However, we encountered a very slow filtration, resulting in long bacteria deactivation times. Slow drainage occurred only when the filter paper was left to dry. It appears that the filter paper with cPAM and micelles develops hydrophobic properties responsible for this very slow filtration. Three approaches were taken to accelerate the very slow drainage all based on modification of binder-micelle interactions: (i) keeping the micelles wet, (ii) modification of the corona, and (iii) replacing cPAM with smaller and more highly charged cationic poly(isopropanol dimethylammonium) chloride (PIDMAC). In all cases, the drainage time of bactericidal filter paper became close to that of untreated filter paper, without decreasing its efficiency. Moreover, replacing cPAM with PIDMAC led to a much more efficient bactericidal filter paper that reduced bacteria viability by more than 6 orders of magnitude. In addition to resolving the hydrophobic drainage hurdle, the three solutions also offer a better understanding of the interaction between cPAM and micelles in the filter paper.

Self-associating cellulose-graft-poly(ɛ-caprolactone) (cellulose-g-PCL) copolymers were successfully synthesized via homogeneous ring-opening polymerization (ROP) of ɛ-CL onto softwood dissolved pulp substrate in ionic liquid 1-N-butyl-3-methylimidazolium chloride ([Bmim]Cl). An organic catalyst N,N-dimethylamino-4-pyridine (DMAP) was compared with the traditional metal-based catalyst (Sn(Oct)(2)) as the catalyst of the reaction, and exhibited higher catalytic activity. By controlling the cellulose:ɛ-CL feed ratio and reaction temperature, the molecular architecture of the copolymers can be altered, as evidenced by FT-IR, (1)H NMR, (13)C NMR, TGA and XRD. The self-assembly behavior of the copolymers in water was investigated and characterized using fluorescence probe, dynamic light scattering (DLS) and SEM. The results showed that the cellulose-g-PCL copolymers could form nanosized micelles (approximately 20-100 nm) in water, and the micelle size and critical micelle concentration (CMC) can be controlled by varying the grafting ratio of PCL. These cellulose-based nanomicelles are expected to be useful in broad application fields., (Copyright © 2012 Elsevier Ltd. All rights reserved.)