Search Results (136)

By incorporating microcapsules with self-healing properties into the coating, a self-healing coating can be obtained, which can repair cracks or damage. In this study, chitosan–sodium tripolyphosphate-coated tung oil microcapsules 1# and 2# with a high encapsulation efficiency were incorporated into a UV-cured topcoat on cherry wood surfaces at different ratios. The results showed that as the microcapsule content increased, the coating’s reflectivity and gloss loss increased, while its impact resistance improved. However, the coating’s adhesion and hardness decreased. The coating containing 6% microcapsule 1# exhibited optimal performance on cherry wood board. The reflectance of the ultraviolet–visible light of the coating was 41.14%, the lightness value was 58.35, the red-green value was 13.96, the yellow-blue value was 25.32, the color difference was 4.47, the gloss reduction rate was 66.84%, the roughness was 1.11 μm, the impact resistance grade was level 4, the adhesion was level 1, the hardness was 3H, and the recovery rate was 17.06%. Comparative analysis revealed that both the chitosan/arabic gum-encapsulated tung oil microcapsules and chitosan–sodium tripolyphosphate-coated tung oil microcapsules could impart self-healing functionality to UV-cured coatings when incorporated into the finish. Notably, the coating system containing 6% chitosan/arabic gum-encapsulated tung oil microcapsules demonstrated optimal performance characteristics when applied to cherry wood substrates. The research findings demonstrate the technical feasibility of achieving self-healing functionality in UV-cured coatings for cherry wood surfaces. Full article

Starch extracted from malanga (Colocasia esculenta) is a biopolymer with considerable industrial potential thanks to its high starch content (70–80% on a dry basis) and small granule size, which give it distinctive functional properties. To expand its applications in advanced processes such as encapsulation, it is necessary to modify its structural and physicochemical characteristics. This study evaluated the effects of ultrasound (US) and chemical cross-linking (CL) on the properties of this starch. US was applied at various times and amplitudes, while CL was performed using sodium trimetaphosphate and sodium tripolyphosphate, with sodium sulfate as a catalyst. US treatment reduced particle size and increased amylose content, resulting in lower viscosity and gelatinization temperature, without affecting granule morphology. Meanwhile, CL induced phosphate linkages between starch chains, promoting aggregation and reducing amylose content and enthalpy, but increasing the gelatinization temperature. The modified starches exhibited low syneresis, making them potentially suitable for products such as pastas, baby foods, and jams. Additionally, ultrasound modification enabled the production of fine starch microparticles, which could be applied in the microencapsulation of bioactive compounds in the food and pharmaceutical industries. These findings suggest that modified malanga starch can serve as a functional and sustainable alternative in industrial applications. Full article

To address the high drying temperature, low yield, and low coating rate that characterize traditional chitosan/gum arabic microcapsules, this study used chitosan/sodium tripolyphosphate (STPP) ionic crosslinking to construct a composite wall, combined with optimized emulsifier compounding (T-80/SDBS), to prepare tung oil self-healing microcapsules. Orthogonal testing determined the following optimal parameters: a core-to-wall ratio of 2.0:1.0, a T-80/SDBS ratio of 4.0:6.0 (HLB = 12.383), an STPP concentration of 4%, and a spray-drying temperature of 120 °C. With these parameters, a yield of 42.91% and coating rate of 68.50% were achieved. The microcapsules were spherical (1–6 μm), with chitosan–STPP electrostatic interactions forming a dense wall. Adding 5% microcapsules to the UV topcoat enabled self-healing after 60 s UV curing: the scratch-healing rate reached 25.25% (width decreased from 11.13 μm to 8.32 μm), the elongation at break increased by 110% to 9.31%, the light transmission remained >82.50%, and the color difference (ΔE = 2.16) showed no significant change versus unmodified coating. Full article

In this study, poly(methyl methacrylate) (PMMA) nanofiber scaffolds reinforced with synthesized nano-hydroxyapatite (n-HA) were fabricated through electrospinning to enhance their potential for applications in bone tissue engineering. Sodium tripolyphosphate (STTP) was utilized as a surfactant to achieve a uniform distribution of particles and improve the structural integrity of the scaffolds. PMMA solutions were prepared at concentrations of the addition of STTP effectively stabilized n-HA dispersion, leading to enhanced fiber morphology, as confirmed by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and transmission electron microscopy (TEM). The PMMA_10_HA_S nanofibers demonstrated a homogeneous fiber distribution with an average diameter of 345.40 ± 53.55 nm and a calcium content of 7.1%. Mechanical testing revealed that adding STTP enhanced the mechanical properties, with the n-HA-reinforced 10 wt.% PMMA nanofibers achieving a maximum tensile stress of 4.16 ± 2.13 MPa and an elongation of 7.1 ± 1.95%. Furthermore, cell cytotoxicity assays of different concentrations (25, 50, 75, and 100 mg/mL) using L929 fibroblast cells demonstrated no cytotoxic effect of PMMA_10_HA_S nanofibers. These findings, reinforced by STTP and n-HA, highlight the potential of PMMA_10_HA_S nanofiber scaffolds as promising candidates for bone tissue applications. Full article

Edge-capping modified MXene membranes with new channels created by lateral nanosheets are of great research significance. After introducing tripolyphosphate (STPP) to Ti edges of Ti₃C₂T_x nanosheets and fabricating the STPP-MXene membranes edge-capping method, this research investigated the performance optimization mechanism of STPP-modified MXene membranes in terms of salt permeability (NaCl, Na₂SO₄, MgCl₂, and MgSO₄) and transmembrane energy barriers (E_salt) through the concentration gradient permeation test. Experimental results demonstrated an approximately 1.86-fold enhancement in salt flux (J_s) compared to the MXene membranes. The solution–diffusion model was also introduced to evaluate the salt solubility (K_s) and diffusivity (D_s) during permeation. Furthermore, analysis of transmembrane energy barriers revealed that STPP modification induced significantly larger reductions in activation energy for magnesium salts (MgSO₄: 55.1%; MgCl₂: 47.4%) compared to sodium salts (NaCl: 30.5%; Na₂SO₄: 30.9%). This phenomenon indicated the weakened electrostatic interactions between high-valent Mg²⁺ and the modified lateral membrane Ti edges, whereas the limited charge density of Na⁺ resulted in relatively modest optimization. The results highlight the contribution of STPP capping on the edges of adjacent lateral nanosheets. Therefore, the modification increased the transportation rate of cations across the MXene membrane by more than twice, thus advancing the application of 2D MXene membranes in resource recovery. Full article

To develop an efficient drug delivery system, we co-entrapped superparamagnetic Fe₃O₄ and the chemotherapeutic drug doxorubicin (DOX) in oleoyl-chitosan (OC) to prepare DOX-entrapped magnetic OC (DOX-MOC) nanoparticles (NPs) through ionic gelation of OC with sodium tripolyphosphate (TPP). The NPs provide magnetically targeted delivery of DOX in cancer therapy. Using folic acid (FA)-grafted OC, FA-conjugated DOX-entrapped magnetic OC (FA-DOX-MOC) NPs were prepared similarly for FA-mediated active targeting of cancer cells with overexpressed folate receptors. Considering DOX loading and release, the best conditions for preparing DOX-MOC NPs were an OC:TPP mass ratio = 1:4 and OC concentration = 0.2%. These spherical NPs had a particle size of ~250 nm, 87.9% Fe₃O₄ content, 53.1 emu/g saturation magnetization, 83.1% drug encapsulation efficacy, and 2.81% drug loading efficiency. FA did not significantly change the physico-chemical characteristics of FA-DOX-MOC compared to DOX-MOC, and both NPs showed pH-dependent drug release behaviors, with much faster release of DOX at acidic pH values found in endosomes. However, FA could enhance the intracellular uptake of the NPs and DOX accumulation in the nucleus. This active targeting effect led to significantly higher cytotoxicity towards U87 cancer cells. These results suggest that FA-DOX-MOC NPs can efficiently deliver DOX for controlled drug release in cancer therapy. Full article

Background/Objectives: Even with improvements in surgical techniques and the application of appropriate antibiotic prophylaxis, wound infections are still major public health problems in low- and middle-income countries. This study proposes the design of new particulate polymeric matrices based on chitosan (CS) for the controlled release of Metronidazole (MTZ), in order for it to be used for the treatment of Clostridium perfringens infections. Methods: The nanoparticles were prepared via inverse emulsion using tannic acid (TA) and sodium tripolyphosphate (TPP) as cross-linking agents. The ratio of CS to TPP, the concentration of CS solution, and the ratio of CS to TA were varied to optimize the synthesis procedure. Nanoparticles have been characterized based on several points of view in order to correctly correlate their properties with synthesis parameters. Results: The FTIR spectra of the analyzed nanoparticles confirmed both the formation of hydrogen bonds between CS and TA and the ionic cross-linking of CS with TPP. The average diameters of the nanoparticles ranged from 70 to 170 nm, whereas the zeta potential values were around 8 mV. Their swelling degree in a weak basic environment, as well as the drug loading/release capacity was influenced, as expected, by the synthesis parameters. The obtained nanoparticles were tested in vitro to evaluate their behavior in the blood environment, the cytotoxic effect, and the antimicrobial activity of nanoparticles loaded with MTZ against Clostridium perfringens cultures. Conclusions: The in vitro obtained results demonstrate that these non-hemolytic and non-cytotoxic particles can be efficient drug delivery systems for the treatment of Clostridium perfringens in wound infections. Full article

Biocatalytic processes for the formation of bioactive compounds and biopolymer preparations that can be applied in pharmaceuticals and cosmetics are gaining increasing interest due to their safety and sustainability, relying on environmentally friendly approaches and biocompatible compounds. In this work, we investigate the implementation of various Deep Eutectic Solvents (DES) in the laccase-catalyzed oxidation of hydroxytyrosol (HT), aiming to produce its oligomer derivatives such as HT dimer and trimer. The composition of the reaction mixture in which the oligomers’ yield was the highest was 70% v/v Bet:PG (1:4 molar ratio). The oligomers formed were subsequently used for the non-enzymatic grafting of chitosan (CS) and the development of bioactive chitosan-based nanogels (NG). Grafted chitosan nanogels were prepared by ionic gelation using sodium tripolyphosphate (TPP) as a cross-linking agent. The functionalized chitosan was characterized using Fourier-Transform Infrared (FTIR) and Nuclear Magnetic Resonance (NMR) spectroscopy, while Scanning Electron Microscopy (SEM) was employed for nanogel characterization. Compared to unmodified chitosan nanogels, grafted chitosan nanogels exhibited almost ten-fold higher antioxidant activity and approximately 20% greater antibacterial activity. Full article

Background/Objectives: Whiter teeth are widely accepted as the most beautiful. With the growing demand for whiter teeth, several manufacturers have launched different brands of whitening toothpaste claiming to be effective in removing tooth stains and whitening teeth. The objective of this in vitro study was to evaluate and compare the whitening effect of eight over-the-counter available toothpastes by measuring the changes in color using a digital colorimeter in a simulated staining–brushing cycle model. Methods: A total of 32 extracted bovine enamel were polished with 1000–2000 grit SIC paper and immersed in a tea staining solution for 30 min at 37 °C to create extrinsic staining. The specimens were randomly divided into eight groups (n = 4) and subjected to a staining–brushing cycle for 2 weeks. During this period, the specimens were stained for 5 min twice, brushed for 2 min twice per day, and immersed in artificial saliva for the remaining time. The colors of the enamel surfaces L*, a*, and b* were recorded, and the color difference (ΔE) was measured before the treatment and after 1 and 2 weeks of the staining–brushing cycle. Results: The repeated measures showed a significant reduction of (ΔE) after 1 week of the staining–brushing cycle in all eight experimental groups (p < 0.05). The (ΔE) was significantly reduced after the second week of the staining–brushing cycle in groups 1, 3, and 5 (p < 0.05). However, it was insignificant in groups 2, 6, 7, and 8 (p > 0.05). Among the tested materials, group 1 showed the highest and group 8 showed the lowest teeth-whitening effects. Conclusions: The over-the-counter toothpaste used in this study showed effective teeth-whitening. Charcoal-based toothpaste showed the highest efficiency in teeth whitening. Full article

In the last 10–15 years, the use of waste refractory materials has significantly increased because it is not economically justified to transport such expensive materials to landfills. This work compared the physical and mechanical properties of refractory concrete samples with those of individual deflocculants—polycarboxilate, sodium tripolyphosphate, and a deflocculant mixture. Three refractory concrete compositions with individual deflocculants and a deflocculant mix were created to choose the best main properties of refractory concrete. Five compositions of refractory concrete specimens were created by partial replacement of chamotte aggregate (CA) by refractory concrete waste (RCW) (100, 75, 50, and 25%). Exothermal profile, structure development and spread were determined for fresh refractory concrete pastes. It was found that with an increase in CA replacement level to RCW, the EXO maximum temperature, spread and structure evolution speed decreases. SEM and porosity tests confirmed density, compressive strength results and structural parameters. The study shows that RCW replacement slows the hydration process, particularly at replacement levels above 33%. However, replacement levels of up to 25% improve compressive strength by 13% due to the additional amount of cement minerals in RCW aggregates, which can participate in the hydration process, making it a viable option for applications where enhanced durability is required, such as in non-critical zones of industrial refractory linings. Full article

In this paper, the effect of soybean isolate protein (SPI) content on the physicochemical properties and oxidative stability of chitosan–sodium tripolyphosphate (CS-STPP)-loaded fish oil capsules was investigated. The SPI/CS-STTP capsules formed after the addition of different amounts of SPI were larger in size and more homogeneous in morphology than the CS-STPP capsules, and the SPI was encapsulated on the surface of the CS matrix, altering the surface properties and morphology of the particles. The study of different CS-to-SPI blend ratios (1:0, 3:1, 2:1, 1:1, 1:2) showed that the water content of the microcapsules increased from 49.79% to 53.27–64.99%, the fish oil loading increased from 17.06% to 18.31–24.89%, and the encapsulation rate increased from 89.42% to 93.90–96.14%. In addition, the addition of SPI reduced the maximum peroxide value from 445 to 264 meq/kg oil. In the simulated in vitro digestion experiments, the addition of various amounts of SPI resulted in a significantly lower percentage of final free fatty acid (FFA) release than observed for CS-STPP capsules alone. These changes observed in the properties may be due to structural differences between CS-STPP capsules and SPI/CS-STPP capsules. All the results confirm that the obtained capsules are promising for the development of functional foods and drugs. Full article

In this work, the mechanical properties of hydrogels based on linear polyethyleneimine (PEI) chemically crosslinked with ethyleneglycoldiglycidyl ether (EGDE) were improved by the ionic crosslinking with sodium tripolyphosphate (TPP). To this end, the quaternization of the nitrogen atoms present in the PEI structure was conducted to render a network with a permanent positive charge to interact with the negative charges of TPP. The co-crosslinking process was studied by ¹H high-resolution magic angle spinning (¹H HRMAS) NMR and X-ray photoelectron spectroscopy (XPS) in combination with organic elemental analysis and inductively coupled plasma mass spectrometry (ICP-MS). In addition, the mobility and confinement of water molecules within the co-crosslinked hydrogels were studied by low-field ¹H NMR. The addition of small amounts of TPP, 0.03 to 0.26 mmoles of TPP per gram of material, to the PEI-EGDE hydrogel resulted in an increase in the deformation resistance from 320 to 1080%, respectively. Moreover, the adsorption capacity of the hydrogels towards various emerging contaminants remained high after the TPP crosslinking, with maximum loading capacities (q_max) of 77, 512, and 55 mg g⁻¹ at pH = 4 for penicillin V (antibiotic), methyl orange (azo-dye) and copper(II) ions (metal ion), respectively. A significant decrease in the adsorption capacity was observed at pH = 7 or 10, with q_max of 356 or 64 and 23 or 0.8 mg g⁻¹ for methyl orange and penicillin V, respectively. Full article

Biopolymer chitosan sub-micron particles (CSMPs) were prepared by the ionic gelation technique crosslinked with sodium tripolyphosphate co-loaded with trans-cinnamaldehyde (TCIN), and either curcumin (CUR) or paclitaxel (PTX). The size of the spherical CSMPs increased from 118 nm to 136 nm and 170 nm after the loading of TCIN and CUR, whereas the loading of PTX led to a slight decrease (114 nm). Polydispersity indexes of all the samples were smaller than 0.4, indicating monodisperse particles. Zeta potential values higher than +40 mV were determined, which is direct proof of the high stability of these nanoparticles. TCIN and PTX release studies in vitro, at pH 6.5 and 7.4, showed a pH dependence on the release rate with a higher value at pH 6.5. However, CUR was not released from CSMPs probably due to strong interactions with CS biopolymer chains. Cytotoxicity studies showed that the systems loaded with TCIN and PTX were more cytotoxic for HeLa cancer cells than for MDCK cells. Moreover, a synergistic effect against HeLa cells was observed for the TCIN-PTX-loaded CSMP samples. The Sensitivity Index indicated that the CSMPs loaded with TCIN have a prospective attraction to carry and release conventional or new chemotherapeutic drugs. This study demonstrates the in vitro efficiency of the obtained drug delivery system, but in vivo studies are necessary to confirm its potential for clinical applications. Full article

Harmful algal blooms (HABs) pose significant threats to ecosystems and human health worldwide, with their frequency and intensity increasing substantially. The present study reports an algal bloom observed in an aquaculture pond near Haizhou Bay in July 2022. The causative species, identified through morphological observation and DNA barcoding analysis, was the dinoflagellate Levanderina fissa (Levander) Moestrup, Hakanen, Gert Hansen, Daugbjerg & M. Ellegaard, 2014, known for causing extensive HAB events in the coastal waters of China. A sharp decline in phytoplankton species diversity was observed during the transition from the pre-bloom to the bloom phase. Furthermore, the uptake of four types of dissolved organic phosphorus (DOP), including glucose-6-phosphate (G6P), adenosine-5-triphosphate (ATP), sodium tripolyphosphate (TPP), and glyphosate, by isolated L. fissa was investigated in the laboratory. The results showed that G6P, ATP, and TPP supported L. fissa growth as effectively as orthophosphate. Additionally, the elevated concentrations of dissolved inorganic phosphorus in the media of the three treatments indicated the involvement of extracellular hydrolysis. However, alkaline phosphatase was not responsible for the hydrolysis of these three forms of DOP. This study demonstrates that the ability of L. fissa to utilize DOP may confer a competitive advantage within phytoplankton communities, potentially leading to algal blooms in aquaculture ponds. Full article

The non-destructive and rapid monitoring system for residual nitrite content in processed meat products is critical for ensuring food safety and regulatory compliance. This study was performed to investigate the application of hyperspectral imaging in combination with machine learning algorithms to predict and monitor residual nitrite concentrations in emulsified pork sausages. The emulsified pork sausage was formulated with 1.5% (w/w) sodium chloride, 0.3% (w/w) sodium tripolyphosphate, 0.5% (w/w) ascorbic acid, and sodium nitrite at concentrations of 0, 30, 60, 90, 120, and 150 mg/kg, based on total sample weight. Hyperspectral imaging measurements were conducted by capturing images of the cross-sections and lateral sides of sausage samples in a linescan mode, covering the spectral range of 1000–2500 nm. The analysis revealed that higher nitrite concentrations could influence the protein matrix and hydrogen-bonding capacities, which might cause increased reflectance at approximately 1080 nm and 1280 nm. Machine learning models, including XGBoost, CATboost, and LightGBM, were employed to analyze the hyperspectral data. XGBoost demonstrated the best performance, achieving an R² of 0.999 and a root mean squared error of 0.095, highlighting its high predictive accuracy. This integration of hyperspectral imaging with advanced machine learning algorithms offers a non-destructive and real-time method for monitoring residual nitrite content in processed meat products, noticeably improving quality control processes in the meat industry. Additionally, real-time implementation in industrial settings could further streamline quality control and enhance operational efficiency. Further research should focus on validating these findings with larger sample sizes and more diverse datasets to ensure robustness. Full article