Colloid and Polymer Science最新文献

Due to its packing-parameter characteristics, Dioleoylphosphatidylethanolamine (DOPE) typically requires a helper molecule to form stable liposomes. In this study, an ion pair between polyethyleneimine and α-lipoic acid was employed as a reduction-responsive amphiphilic helper molecule and applied to stabilize DOPE liposomes. The ion pair exhibited UCST-type behavior, and its phase transition temperature decreased from approximately 42.6 °C to 37.7 °C, 29.6 °C, and 22.9 °C upon treatment with 5, 10, and 20 mM dithiothreitol, respectively. DOPE liposomes prepared using the ion pair enabled calcein encapsulation, and the DOPE: IP mass ratio of 10:1 showed the highest quenching efficiency of 48.1% together with a low polydispersity index of 0.105, indicating uniform liposome formation. Transmission electron microscopy further confirmed the formation of multilamellar structures in DOPE liposomes incorporating the ion pair. In release experiments, Lip-CHEMS (10:1) exhibited negligible release regardless of DTT, whereas Lip-IP (10:1) showed a stepwise increase in release with increasing DTT concentration, reaching approximately 12% at 20 mM DTT. Within the temperature range of 25–45 °C, temperature elevation alone did not produce a clear additional increase in release. These results show that the PEI/ALA ion pair is not merely an alternative to conventional DOPE helper molecules, but a functional helper molecule that simultaneously enables bilayer stabilization and reduction-triggered modulation of membrane permeability. Therefore, this study provides a formulation strategy for reduction-responsive DOPE liposomes capable of selective release under reducing conditions relevant to the tumor microenvironment.

Graphical Abstract

Schematic representation of reduction-responsive ion pairs formed from polyethyleneimine and α-lipoic acid, and DOPE liposomes stabilized by the ion pairs.

Poly(p-hydroxystyrene) (PHS) serves as a key raw material for synthesizing deep ultraviolet(KrF) photoresist film-forming resins. To address the issues of lengthy preparation times and suboptimal performance associated with conventional heating methods, this study proposes a novel microwave-assisted polymerization process for synthesizing poly(4-acetoxystyrene), the precursor of PHS, thereby achieving efficient synthesis of poly(4-acetoxystyrene). 4-Acetoxystyrene was used as the monomer, benzoyl peroxide (BPO) as the initiator, and toluene as the solvent. To verify the feasibility of microwave polymerization, the dielectric properties of the monomer, solvent, initiator, and their mixed solution were characterized by the resonant cavity perturbation method at 2450 MHz, and the thermal stability of the reaction system was evaluated by thermogravimetric analysis (TG). Polymerization experiments were conducted using a laboratory-built microwave reactor to monitor the temperature profile during reaction. The results showed that all components and the mixed solution exhibited excellent microwave dielectric loss characteristics. Finally, the samples were systematically characterized by ¹H nuclear magnetic resonance spectroscopy (¹H NMR), Fourier transform infrared spectroscopy (FT-IR), and gel permeation chromatography (GPC). The results confirmed the successful synthesis of poly(4-acetoxystyrene) with a weight-average molecular weight (M_w) of 23,641 g/mol, a polydispersity index (PDI) of 1.86, and a monomer conversion of 98.86%. Furthermore, the mechanism of microwave action in the polymerization process was proposed. This study provides important guidance for the industrial preparation of poly(4-acetoxystyrene) and offers new insights into the efficient synthesis of functional polymer resins.

Protein and polypeptides drugs require frequent administration due to low bioavailability and poor stability, leading to reduced patient compliance. We developed a nano-delivery system for the efficient delivery of bovine serum albumin (BSA) based on carboxymethyl-β-cyclodextrin (CM-β-CD) and polyethylene glycol-grafted chitosan (CS-g-mPEG) via polyelectrolyte complexation method. The effects of factors such as volume ratio, pH and grafting degree on particle size, stability, and drug release behavior were investigated. Under optimal conditions, the size of nanoparticle was 223 nm with polydispersity index of 0.131, and the Zeta potential was + 23.86 mV. In vitro release studies demonstrated the nanoparticles can achieve pH-responsive drug release, with release rate of 74.3% in simulated intestinal fluid (pH = 6.8), following the Ritger-Peppas model. Moreover, this nano drug carrier exhibits excellent biocompatibility and long-circulation performance, providing a novel strategy with potential applications for protein drug delivery.

In this study, κ-carrageenan-based hydrogel beads doped with kefir biomass were synthesized and characterized using Fourier-transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). A Box-Behnken experimental design was employed to evaluate the effects of the kefir biomass ratio, cross-linker (KCl) concentration, and medium pH on the swelling capacity of the beads. ANOVA results demonstrated that the cross-linker concentration and the interactions between these factors significantly influenced the swelling behavior. Under optimized conditions (15% kefir biomass, 0.5 M KCl, and pH 5.2), a maximum swelling degree of 32.03 g_solution/g_beads was achieved. Furthermore, the beads were loaded with a red food dye as a model drug to investigate their release behavior. Kinetic studies revealed that the swelling process follows a pseudo-first-order model, while the release of the model drug aligns with the Ritger-Peppas mechanism.

Two phosphorus-containing polymethacrylate viscosity index (VI) improvers were designed and synthesised successfully via free radical polymerisation. Specifically, the two polymers were prepared by copolymerising dodecyl methacrylate with two different phosphorus-containing monomers, namely 2-hydroxyethyl methacrylate phosphate and bis[2-(methacryloyloxy)ethyl] phosphate, respectively. It is noteworthy that the synthesized polymers demonstrate remarkable VI-improving performance. When incorporated at a concentration of 5 wt% into the mineral base oil (150 N, base oil grade), all polymer samples effectively enhance the viscosity index. As multifunctional additives, they also demonstrate superior tribological performance in comparison to the commercially available 6300 V—their shear stability is superior, indicating excellent shear resistance. In situations involving extreme pressure performance, the two polymers (P(LMA-MP) and P(LMA-DP)) have been shown to significantly increase the load-carrying capacity of the 150 N mineral base oil from 200 N to a maximum of 600 N. They have also been demonstrated to exhibit remarkable advantages in terms of anti-wear and friction-reduction properties, effectively lowering the friction coefficient and wear volume. The structural modification of the copolymers (introduction of phosphorus-containing groups) is responsible for the enhanced tribological performance: Energy-dispersive X-ray spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS) analyses of the friction surfaces reveal that a protective friction film, mainly composed of iron oxide and iron phosphate, is formed, while the polymethacrylate backbone ensures their excellent VI-improving capability.

Water pollution poses a severe threat to human health and ecological systems, thereby demanding high-performance adsorbents for wastewater treatment. Herein, a novel composite hydrogel (CA-β-CD/P(AA-co-AM)) was synthesized via radical polymerization using citric acid-modified β-CD (CA-β-CD). Citric acid modification introduced functional sites, tuned cavity structure, and linked β-CD units into oligomer, overcoming native β-CD’s limitations to serve as an ideal hydrogel component. The incorporation of CA-β-CD into P(AA-co-AM) formed a porous network, enabled synergistic interactions, enhanced stability, and integrated CA-β-CD’s adsorption superiority with the polymer’s robust matrix. The structure and properties of the composite hydrogel were characterized by FT-IR, ¹H NMR, SEM, TGA, GPC, and XPS. It showed outstanding methylene blue (MB) adsorption via host–guest inclusion, hydrogen bonding, and electrostatic interactions, with a maximum capacity of 3743.23 mg/g. Adsorption followed pseudo-second-order kinetics and Langmuir isotherm, with rate controlled by intra-particle and liquid film diffusion. Importantly, the composite hydrogel maintained excellent reusability — after 10 consecutive adsorption–desorption cycles, the MB removal rate (R) remained above 92%. This work provides a promising strategy for cyclodextrin-derived adsorbents in dye wastewater treatment. 

Graphical Abstract

For the first time, a comprehensive analysis of the statistical distribution of the lap-shear strength (σ) developed at a symmetric interface of amorphous poly(2,6-dimethyl-1,4-phenylene oxide) (PPO) at a temperature of the autohesion origination (T_a^origin) is carried out. After the contact of the two PPO specimens for 24 h at a temperature well below the PPO bulk glass transition temperature (T_g^b), at T_a^origin = T_g^b − 126 °C, the PPO−PPO interface was self-bonded and thereafter fractured at ambient temperature. The σ distribution dataset σ(n) including n measurements is investigated on its conformity to the Weibull and normal distributions. It is shown that the Weibull and normal probability plots, the Gaussian probability density function histogram, and a number of the standard tests for normality describe the σ distribution with varying degrees of success. Among those, the most favorable statistical results supporting the null hypothesis of normality are obtained in the standard tests for normality (in 6 out of 8 performed). An attempt to describe the distribution curve σ(n) more correctly is undertaken. It is found that the most appropriate distribution forms are the phenomenological logarithmic and exponential relationships logσ ∼ n, σ ∼ e^{(a + bn)} and σ ∼ (1– e^an) where a and b are the constants. For further treatment of the σ distribution, a new statistical relationship P_j = c + dlnσ where P_j is the cumulative probability of failure and c and d are the constants is proposed. It is proposed to use d as a data scatter parameter. A new statistical parameter, d/m, where m is the Weibull modulus is introduced. A comparison with an asymmetric polystyrene–PPO interface is performed.

Lipophilic compounds encapsulated in Pickering emulsions can be inhibited the access of oxygen, prooxidants, and free radicals and therefore be applied to the controlled bioactive delivery. Cellulose nanofibrils (CNFs) stabilized Pickering emulsions (PE) for encapsulation and delivery of β-carotene (β-C) were prepared through high intensity ultrasound (HIU), high-pressure homogenization (HPH) or the HIU + HPH dual emulsifying process. Emulsion properties, encapsulation efficiency (EE), retention rate (RR), bioaccessibility of β-C and free fatty acids rate (FFA%) impacted by single or dual emulsifying process, the oil fraction Φ and the concentration of CNFs suspension (CNFs%) was investigated. Compared to the single HPH or HIU which usually cannot enhance emulsification effect through increasing accounts or times, the HIU + HPH dual emulsification method is beneficial to gain the more homogeneous fine emulsion droplets and durable stable emulsion status. All of β-C-encapsulated PE samples (Φ ≤ 0.5) prepared by 2.0%w/w CNFs suspension had long-term stability for at least 150 days storage. Although EE of β-C in the HIU + HPH samples was lower than that in the HPH or HIU samples, EE of β-C in the HIU + HPH samples at high Φ (= 0.4) condition was closed to the maximum of that in the HIU samples, and RR of β-C in the HIU + HPH samples during storage are much better than that in the HPH or HIU samples. Furthermore, RR of β-C in the HIU + HPH samples at Φ = 0.4 was changed insignificantly after storage intervals, and bioaccessibility of β-C in the HIU + HPH samples at Φ = 0.2 and CNFs%=1.2 can reach the highest value 26.76 ± 0.13% after simulating intestinal digestion. There is a positive relation between the final FFA% and bioaccessibility of β-C. These findings indicate that PE prepared by HIU + HPH at appropriate Φ and CNFs% is an excellent carrier and controlled deliverer for lipophilic bioactive substances.

Cinnamaldehyde oil (CO) is a potent natural antimicrobial agent; however, its volatility and poor aqueous stability limit direct biomedical application. Encapsulation within biopolymer-based gels offers a promising strategy for controlled delivery in wound care. Herein, bioactive chitosan/bacterial cellulose/polyacrylate (CS/BC/PA) gel films were fabricated via ionic crosslinking with sodium tripolyphosphate. The films were characterized using FTIR, SEM, XRD, and TGA, and evaluated for swelling, mechanical properties, in vitro degradation, CO loading/release, antibacterial activity, and cytocompatibility. Based on the obtained results the gels exhibited high swelling (> 400%) and tunable degradation, with weight loss decreasing from 26.37 ± 1.78% to 6.25 ± 0.95% over 15 days. Mechanical strength improved from 1.24 ± 0.16 to 8.42 ± 0.91 kPa with increased crosslinking. CO loading efficiency reached 84.53 ± 2.43%, with sustained release up to 64.85 ± 3.24% at 420 min, following Korsmeyer–Peppas kinetics (R² = 0.922, n = 0.57). Antibacterial activity showed inhibition zones of 15.65 ± 1.32 mm and 17.90 ± 1.54 mm against S. aureus and K. pneumoniae, respectively, while cell viability remained > 75%. In conclusion, the developed BGFs demonstrate controlled release, antibacterial efficacy, and cytocompatibility, indicating potential as multifunctional wound dressing materials, warranting further biological validation.

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This research gives a greener approach for developing sustainable functional textiles using plant-based bioactive compounds. Poly(methyl methacrylate) (PMMA) microcapsules containing tea tree oil (TTO) and lutein (LU) were synthesized by using oil-in-water emulsion technique, and applied to polyester-cotton (PC) blended fabric by using pad steam method. The PMMA@LU-TTO microcapsules were characterized by scanning electron microscopy (SEM) to analyze its morphology and uniform deposition of microcapsules on fabric surfaces without compromising structural integrity, while particle size distribution was analyzed by particle analyzer. The Zeta potential, Fourier Transmission Infrared (FTIR) and X-ray diffraction (XRD) confirmed their structural stability and encapsulation of active agents. The thermal stability of microcapsules and treated fabrics were analyzed by Thermogravimetric analysis (TGA). After 30 washing cycles the treated fabrics with 15% PMMA@LU-TTO microcapsules exhibited 90% mosquito repellency at zero wash and retained 80% repellency indicating excellent durability. The finished fabrics also shows excellent air permeability, water absorbency, and significant antibacterial activity. Accordingly, it is firm that adding oil does not influence the physical arrangement of PMMA@LU-TTO microcapsules. Hence, this research gives a greener approach for the development of highly durable functional mosquito-repellent textiles having excellent antibacterial activity.

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