Differential Scanning Calorimetry Results Research Articles

DNA interaction of selected tetrahydropyrimidine and its effects against CCl4-induced hepatotoxicity in vivo: Part II.

Tetrahydropyrimidine (compound A = methyl 4-[4'-(heptyloxy)-3'-methoxyphenyl]-1,6-dimethyl-2-thioxo-1,2,3,4-tetrahydropyrimidine-5-carboxylate) was chosen for in vivo studies after exhibiting noteworthy in vitro activity against the K562 and MDA-MB-231 cell lines, with IC50 values of 9.20 ± 0.14 µM and 12.76 ± 1.93 µM, respectively. According to experimental (fluorescence titration, viscosity, and differential scanning calorimetry) results, A interacts with DNA via the minor groove. In vivo, acute oral toxicity studies in Wistar albino rats proved no noticeable symptoms of either toxicity or death during the follow-up period. Genotoxic and antigenotoxic studies at three different concentrations of A (5, 10, and 20 mg/kg of body weight) in Wistar albino rats showed that the dose of 5 mg/kg body weight did not cause DNA damage and had a remarkable DNA protective activity against CCl4-induced DNA damage, with a percentage reduction of 78.7%. It is also important to note that, under the investigated concentrations of A, liver damage is not observed. Considering all experimental outcomes realized under various in vivo investigations (acute oral toxicity, genotoxicity, antigenotoxicity, and biochemical tests), compound A could be a promising candidate for further clinical testing.

Enhancing the dyeability of polyurethane fibers by introducing protonated tertiary amine groups

Traditional polyurethane fibers (CPUF) are widely used in the preparation of blend clothing in order to improve the elasticity and comfort of fabrics. However, there has been a problem of low acid dye adsorption for CPUF, resulting in light hue of dyed CPUF. In this work, a poly (HMDI-BHOPA) was prepared with dicyclohexylmethane 4,4′-diisocyanate (HMDI) and 1,4-(2-hydroxyethyl) piperazine (BHOPA), and then added into the CPUF spinning solution for the preparation of modified polyurethane fibers (BPUFs) through dry-spinning technology. Tertiary amine groups were introduced after the addition of poly (HMDI-BHOPA), which could be protonated at acidic conditions to form binding sites for acid dyes, further enhancing the adsorption capacity of the fibers. Nuclear magnetic resonance spectroscopy (1H and 13C NMR) was used to confirm the structure of poly (HMDI-BHOPA). The results of differential scanning calorimetry (DSC) and thermogravimetry analysis (TGA) demonstrated that the addition of poly (HMDI-BHOPA) had little effect on the glass transition temperature and thermal stability of BPUFs. The addition of poly (HMDI-BHOPA) affected the ordered arrangement of hard segments and reduced crystallization enthalpy of hard and soft segments in polyurethane. Hence, the elastic recovery of BPUFs showed little change, and the elongation at break and break strength decreased compared to CPUF. Zeta potential testing results showed that BPUFs was protonated under acidic conditions. Dyeing results proved the enhancement of dyeability of BPUFs. The dyeing kinetics and thermodynamics of acid dyes on BPUFs were studied to investigate the dyeing mechanism. From the dyeing kinetics results, both CPUF and BPUFs fitted Elovich model. From dyeing thermodynamics results, Langmuir model showed a better applicability for BPUFs at a low pH and temperature condition, while Freundlich model fitted better for CPUF.

Novel differential scanning calorimetry (DSC) application to select polyhydroxyalkanoate (PHA) producers correlating 3-hydroxyhexanoate (3-HHx) monomer with melting enthalpy.

Polyhydroxyalkanoate (PHA) is an environmental alternative to petroleum-based plastics because of its biodegradability. The polymer properties of PHA have been improved by the incorporation of different monomers. Traditionally, the monomer composition of PHA has been analyzed using gas chromatography (GC) and nuclear magnetic resonance (NMR), providing accurate monomer composition. However, sequential analysis of the thermal properties of PHA using differential scanning calorimetry (DSC) remains necessary, providing crucial insights into its thermal characteristics. To shorten the monomer composition and thermal property analysis, we directly applied DSC to the analysis of the obtained PHA film and observed a high correlation (r2 = 0.98) between melting enthalpy and the 3-hydroxyhexanoate (3-HHx) mole fraction in the polymer. A higher 3-HHx fraction resulted in a lower melting enthalpy as 3-HHx provided the polymer with higher flexibility. Based on this, we selected the poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (P(3HB-co-3HHx)) producing strain from Cupriavidus strains that newly screened and transformed with vectors containing P(3HB-co-3HHx) biosynthetic genes, achieving an average error rate below 1.8% between GC and DSC results. Cupriavidus sp. BK2 showed a high 3-HHx mole fraction, up to 10.38mol%, with Tm(℃) = 171.5 and ΔH of Tm (J/g) = 48.0, simultaneously detected via DSC. This study is an example of the expansion of DSC for PHA analysis from polymer science to microbial engineering.

Experimental investigation on the thermal characteristics of Kevlar/hemp intraply hybrid composites: Influence of various weaving designs

In this work, several weaving designs of intra-ply woven fabric Kevlar/hemp fiber (KHE) reinforced epoxy hybrid composites are developed and their thermal characteristics are examined. Thermogravimetric analysis showed that intra-ply hybrid of plain and basket weave designs possessed highest thermal stability. The different weaving patterns of KHE hybrid composites have no effect on the glass transmission temperature (Tg) value as inferred from the differential scanning calorimetry results. The thermomechanical analysis clearly demonstrates the superior dimension stability of the hybrid composites with basket weave. Dynamic mechanical analysis reveals that twill weave KHE have exhibited the maximum storage modulus (2021 MPa), loss modulus (210 MPa) and lower tan delta (0.3090) values compared to all other composites. Based on the obtained results, it is denoted that all the fabricated KHE hybrid composites displayed improved thermal performance. It may be suitable for applications in thermal insulation panels, fire-resistant clothing, and automotive underbody shields.

Effect of extrusion using plasma-activated water on the structural, physicochemical, antioxidant and in vitro digestive properties of yam flour

The synergistic effects of plasma-activated water (PAW) and twin-screw extrusion (TSE) on the structural, physicochemical, antioxidant, and digestive properties of yam flour (YF) were studied. Compared to common TSE, PAW-TSE reduced the protein, starch, and polyphenol contents, swelling power, and gel property of YF, while PAW-TSE enhanced the flavonoid content, whiteness index, solubility, and antioxidant property of YF. Moreover, the results of structural characterization and differential scanning calorimetry indicated that the long-range or short-range ordering, and gelatinization enthalpy of starch in YF were reduced after PAW-TSE, while the structure ordering of proteins in YF increased. Furthermore, the in vitro digestibility results demonstrated a reduction in the rate of enzymatic hydrolysis, coupled with an increase in total contents of slowly digestible and resistant starch after PAW-TSE. It should be noted that TSE using PAW prepared by a longer plasma treatment resulted in a more significant improvement effect on YF.

Influence of Processing Parameters on Mechanical Properties and Degree of Crystallization of Polylactide.

This work attempts to assess the influence of process parameters on the change of mechanical properties and the degree of crystallinity of polylactide (PLA). PLA is a biodegradable material that has been widely used in various areas-from packaging, through medicine, to 3D printing, where it is used to produce prototypes. The method of processing is important, because the technological process and its parameters have a significant impact on the quality of the finished product. Their appropriate selection depends on quality and mechanical properties. The process parameters have an impact on the structure of PLA, specifically on the share of the crystalline phase, which is also important from the point of view of the functional properties of the finished product. This work assessed the impact of the technological parameters of the injection process on the final properties of the obtained samples. The obtained results of static tensile strength, hardness and differential scanning calorimetry (DSC) analysis confirm that changing these parameters affects the material properties.

Novel kraft-lignin-based adhesives for the production of particleboards

Lignin is produced worldwide in pulp mills and is currently mainly used for energy recovery. Because of its chemical properties, one possible utilisation is the production of lignin-based materials. Currently, developed lignin-based adhesives are based mainly on lignosulfonate instead of kraft lignin since lignosulfonate is more reactive than kraft lignin. However, worldwide substantially more kraft lignin is produced. The presented research deals with the development of resin chemically modified with kraft lignin up to 40% (w/w) content of kraft lignin. The synthesis of adhesives is described, and developed adhesives are characterised. Namely, viscosity, mechanical properties of resins and results of differential scanning calorimetry are presented. Furthermore, the developed kraft-lignin-based adhesives were used for the production of particleboards. Pre-pressing in a cold press followed by hot pressing in a laboratory press was used for the production of particleboards. The physical (thickness swelling, moisture uptake, vertical density profile), as well as mechanical (internal bonding, modulus of rupture, modulus of elasticity in three-point bending) properties of particleboards, were evaluated. The results clearly show that kraft lignin can be used for the production of lignin-based adhesives for the production of particleboards.

Insight into in situ enzymatic transesterification modification of polyethylene terephthalate fibers with polyethylene glycol

Polyethylene terephthalate (PET) fabric was enzymatically modified with polyethylene glycol (PEG). Lipase from Aspergillus oryzae was used as a catalyst. The wetting behavior of the modified PET fabric was characterized by the water contact angle, water adsorption dynamics and moisture regain. The initial water contact angle of the modified fabric decreased from 129.3° to 74.9°. The water absorption dynamics results indicated that the equilibrium water absorption amount of the modified fabric was approximately 10 times greater than that of the untreated sample. The initial absorption rate (Vinit) of the modified fabric was almost 30 times higher than that of the untreated fabric. The moisture regain reached 3.52% after modification. Scanning electron microscopy revealed granular and sheet coatings on the surface of the modified fabric. Chemical linkage of PEG onto the PET fibers was confirmed by attenuated total reflection–Fourier transform infrared spectroscopy. The modification had no significant effect on the thermal properties of the PET fabrics according to the thermogravimetric curve and differential scanning calorimetry results. The mechanical properties of the modified fabric were slightly improved. Therefore, in situ enzymatic transesterification between PET and PEG could be a potential novel modification approach for adding value to PET fiber textiles.

Euglena gracilis Protein: Effects of Different Acidic and Alkaline Environments on Structural Characteristics and Functional Properties.

Due to the growing demand for human-edible protein sources, microalgae are recognized as an economically viable alternative source of proteins. The investigation into the structural characteristics and functional properties of microalgin is highly significant for its potential application in the food industry as an alternative source of protein. In this research, we extracted protein from Euglena gracilis by using alkaline extraction and acid precipitation and investigated its structural characteristics and functional properties in different acidic and alkaline environments. The molecular weight distribution of Euglena gracilis protein (EGP), as revealed by the size exclusion chromatography results, ranges from 152 to 5.7 kDa. EGP was found to be rich in hydrophobic amino acids and essential amino acids. Fourier infrared analysis revealed that EGP exhibited higher α-helix structure content and lower β-sheet structure content in alkaline environments compared with acidic ones. EGP exhibited higher foaming properties, emulsifying activity index, solubility, free sulfhydryl, and total sulfhydryl in pH environments far from its isoelectric point, and lower fluorescence intensity (2325 A.U.), lower surface hydrophobicity, larger average particle size (25.13 µm), higher emulsifying stability index, and water-holding capacity in pH environments near its isoelectric point. In addition, X-ray diffraction (XRD) patterns indicated that different acidic and alkaline environments lead to reductions in the crystal size and crystallinity of EGP. EGP exhibited high denaturation temperature (Td; 99.32 °C) and high enthalpy (ΔH; 146.33 J/g) at pH 11.0, as shown by the differential scanning calorimetry (DSC) results. The findings from our studies on EGP in different acidic and alkaline environments provide a data basis for its potential commercial utilization as a food ingredient in products such as emulsions, gels, and foams.

Glycidyl methacrylate co-polymer emulsion-based heat and water-resistant wood adhesive

This work aims to add an epoxy-ended co-monomer to polyvinyl acetate (PVAc) emulsion adhesive-based wood adhesive to improve its resistance to heat and moisture. Here, glycidyl methacrylate (GMA), vinyl neodecanoate (VeoVa), and vinyl acetate (VAc) emulsion copolymers have been created and evaluated as wood adhesives. To prepare the emulsion-based adhesive samples, a polyvinyl alcohol (PVA) solution, aluminium chloride solution, preservatives, and a plasticizer are added. Following that, the poly(VAc–VeoVa–GMA) based adhesive sample is compared with the VAc, VeoVa, and methyl methacrylate (MMA) (poly(VAc-VeoVa-MMA)) co-polymer-based adhesive. Tensile shear strength of wood joints under dry and wet conditions was tested in compliance with EN 204-205 standard to assess the adhesives’ performance. The EN 14257 standard, which defines the shear stress of wood joints at 80 °C, was used to assess the heat resistance of the wood adhesives. Tests on the hardness of films confirmed the results of differential scanning calorimetry, which indicated that the glass transition temperature in the GMA-based adhesive was significantly higher than in the MMA-based adhesive. After 6 h of bonding, EN 204 shows that the tensile shear strength of a GMA-based adhesive increased by 15.56% in a dry environment, by 16.67% in a wet environment and 37.84% heat resistance when compared to a co-polymer-based adhesive based on MMA. The approach that was developed provides a simple and useful way of developing adhesives with enhanced heat, water, and bonding strength resistance.

Calorimetric and Raman spectroscopic studies of zwitterionic and anionic membrane interactions of phenolic compound coumarin

It is well known that polyphenols possess potent antioxidant qualities. However, the precise antioxidant action mechanism of phenolic compounds is still not well defined. It is evident that understanding the molecular mechanisms behind polyphenol-lipid interactions is necessary to comprehend this impact. The objective of this work is to examine the effect of phenolic compound coumarin on the physicochemical properties of cell membrane models. To accomplish this goal, model membranes made up of zwitterionic dimyristoylphosphatidylcholine (DMPC) and anionic dimyristoylphosphatidylglycerol (DMPG) lipids were used. These lipid species are the main component of the mammalian and gram-positive bacteria membranes, respectively. Differential scanning calorimetry (DSC) and Raman spectroscopy were applied for studying the interaction of coumarin with DMPC and DMPG. From the DSC results, it was found that pretransition was abolished for both lipid systems at 20 mol% coumarin. Main phase transition shifted to lower temperatures and broadened, but there was not a complete disappearance of main transition and coumarin was not fully miscible. A sharp peak at a higher temperature and a broad shoulder at a lower temperature of the main transition of DMPC were detected when compared to coumarin/DMPG binary system. A reduction in calorimetric enthalpy and entropy values of coumarin/DMPC system at 20 mol% was observed whereas an increase in these calorimetric parameters for coumarin/DMPG system occurred. Thus, the disorder was caused when 20 mol% coumarin interacts with DMPC lipid bilayers. The increase in enthalpy could be a result of the 20 mol% coumarin interactions with DMPG lipid bilayers or a possible generated partial interdigitation. From the Raman results, the peak height Raman intensity ratio I1090/I1130 showed that coumarin induces disorder in the DMPG bilayers in the gel phase due to the increasing gauche:trans ratio. According to the results obtained by DSC and Raman spectroscopy, it was found that coumarin has a varied effect on membranes made from lipids with choline and glycerol head groups. Thus, it is obvious that the polyphenol/membrane interactions can be significantly impacted by the lipids’ structural variations.

Eutectic mixtures containing the active pharmaceutical ingredient ezetimibe: Phase diagrams, solid state characterization and dissolution profiles

Cardiovascular disease represents the leading cause of death worldwide, according to the World Health Organization (WHO) report. One of the treatment strategies is the use of the drug ezetimibe (EZT). This drug is a cholesterol absorption inhibitor with low aqueous solubility, which affects its therapeutic efficacy. The purpose of this paper was to obtain eutectic materials of EZT with methylparaben (MPB), salicylic acid (SCA) and nicotinamide (NTM) coformers, and to study their phase diagrams, dissolution properties and hygroscopicity to assess possible enhancements. Phase and Tamman diagrams were constructed using differential scanning calorimetry (DSC) results. The eutectic materials were characterized by powder X-ray diffraction (PXRD) and polarized light optical microscopy (OM). The hygroscopicity of the materials was assessed at different relative humidities (RH) through dynamic vapor sorption (DVS). The dissolution study was conducted with the materials in powder form, with paddle dissolution, rotating at 50 rpm, in 900 mL of aqueous buffer solution at pH 6.8 and 37 °C. The phase diagrams demonstrated that EZT formed eutectic systems with eutectic molar fractions of 0.59, 0.67 and 0.69 for EZT-SCA, EZT-NTM and EZT-MPB, respectively. The three eutectic materials are characterized as microcrystalline conglomerates of their components. In terms of the hygroscopic behavior of EZT at different RHs, eutectic materials demonstrated lower susceptibility to monohydrate formation compared to the anhydrous form. In dissolution studies, EZT-SCA and EZT-MPB solubilized EZT in amounts 22 % higher than the pure drug in 15 min. On the other hand, EZT-NTM eutectic suppressed the dissolution of EZT down to 56 % at the same time. The results indicated the possibility of obtaining materials with enhanced properties using eutectic mixtures, with improved dissolution rates and hygroscopic stability.

Analytical Aspects of ANSA-BSA Association: A Thermodynamic and Conformational Approach.

Many studies have demonstrated the manner in which ANS interacts with bovine serum albumin (BSA), although they are limited by the extremely low solubility of dye. The present study demonstrates the binding of ANSA dye with BSA, and since this dye can easily replace ANS, it not only simplifies research but also improves sensor accuracy for serum albumin. A combination of calorimetry and spectroscopy has been employed to establish the thermodynamic signatures associated with the interaction of ANSA with the protein and the consequent conformational changes in the latter. The results of differential scanning calorimetry reveal that when the concentration of ANSA in solution is increased, the thermal stability of the protein increases substantially. The fluorescence data demonstrated a decrease in the binding affinity of ANSA with the protein when pH increased but was unable to identify a change in the mode of interaction of the ligand. ITC has demonstrated that the mode of interaction between ANSA and the protein varies from a single set of binding sites at pH 5 and 7.4 to a sequential binding site at pH 10, emphasizing the potential relevance of protein conformational changes. TCSPC experiments suggested a dynamic type in the presence of ANSA. Molecular docking studies suggest that ANSA molecules are able to find ionic centers in the hydrophobic pockets of BSA. The findings further imply that given its ease of use in experiments, ANSA may be a useful probe for tracking the presence of serum albumin and partially folded protein states.

Formulation and Characterization of Triamcinolone Acetonide Acetate-Loaded Microspheres Prepared by a Static Mixing Technique

Purpose: Reproducibility and scale-up production of microspheres through spray drying present significant challenges. In this study, biodegradable microspheres of Triamcinolone Acetonide Acetate (TAA) were prepared using a novel static mixing method by employing poly( lactic-co-glycolic acid) (PLGA) as the sustained-release carrier. Methods: TAA-loaded microspheres (TAA-MSs) were prepared using a static mixing technique. The PLGA concentration, polyvinyl alcohol concentration (PVA), phase ratio of oil/water, and phase ratio of water/solidification were optimized in terms of the particle size, drug loading (DL), and encapsulation efficiency (EE) of TAA-MSs. The morphology of TAA-MSs was examined using Scanning Electron Microscopy (SEM), while the physicochemical properties were evaluated through X-ray diffraction (XRD), Differential Scanning Calorimetry (DSC), and Fourier Transform Infrared Spectroscopy (FT-IR). The in vitro release of TAA-MSs was compared to that of the pure drug (TAA) using a water-bath vibration method in the medium of pH 7.4 at 37°C. Results: The formulation composition and preparation condition for the preparation of TAA-MSs were optimized as follows: the PLGA concentration was 1%, the phase ratio of oil(dichloromethane) /water (PVA solution) was 1:3, the phase ratio of water (PVA solution)/solidification was 1:2. The optimized TAA-MSs displayed spherical particles with a size range of 30-70 μm, and DL and EE values of 27.09% and 98.67%, respectively. Moreover, the drug-loaded microspheres exhibited a significant, sustained release, with 20% of the drug released over a period of 28 days. The XRD result indicated that the crystalline form of TAA in microspheres had been partly converted into the amorphous form. DSC and FT-IR results revealed that some interactions between TAA and PLGA occurred, indicating that the drug was effectively encapsulated into PLGA microspheres. Conclusion: TAA-loaded PLGA microspheres have been successfully prepared via the static mixing technique with enhanced EE and sustained-release manner.

Effect of Heat Treatment on Some Thermodynamics Analysis, Crystal and Microstructures of Cu-Al-X (X: Nb, Hf) Shape Memory Alloy

Heat treatment is an important technique that can improve the properties of shape memory alloys. In this study the effect of heat treatment at three different temperatures (973 K, 1073 K and 1173 K) on some thermodynamics parameters, crystal structure, and microstructure of Cu_86 Al_12 Nb_2 and Cu_86 Al_12 Hf_2 (mass %) Shape Memory Alloy has been investigated. After heat treatment, the change in the thermal properties of the samples was determined using Differential Scanning calorimetry (DSC). The effect of heat treatment on the crystal and microstructure of the alloy samples were determined at room temperature using X-ray diffraction (XRD), Scanning Electron microscopy (SEM) device. The DSC result showed that in both samples the temperature hysteresis was decreased after heat treatment. Also grain size was decreased by increasing the treatment temperature in both samples. And finally, optical images represented that Hafnium (Hf) is more dissolved in the alloy compared to Niobium (Nb).

Thermally induced phase separation of UHMWPE mixture with dioctyl adipate: Competition of liquid–liquid phase separation and polymer crystallization

The thermal behavior of ultra-high molecular weight polyethylene (UHMWPE) with dioctyl adipate (DOA) was investigated by the differential scanning calorimetry (DSC) method. Capillary-porous bodies were obtained via thermally induced phase separation of DOA mixtures with polyethylenes of different molecular weight at different cooling rates. Analysis of the morphology of the prepared porous bodies together with DSC data and results of cloud point estimation revealed an unexpected effect of a cooling rate on the type of phase separation occurring in the mixture during its cooling from homogeneous state. Particularly it was shown that increase in the cooling rate reduces the probability of realization of liquid – liquid phase separation in the mixture. It was argued that such behavior, different from the standard semicrystalline polymers, is a result of kinetic hindrance of liquid – liquid phase separation in mixtures containing a polymer with such a high molecular weight.

Thermal, morphological, and structural characterization of starch-based bio-polymers for melt spinnability

Abstract The demand for sustainable textiles has increased research on bio-based biopolymers. Fiber spinning from starch biopolymer and its blends was widely attempted using electro-spinning; however, it is less attempted using melt spinning which is an industrially feasible method. In this study, native tapioca starch is converted into thermoplastic starch (TPS), blended with polylactic acid (PLA), and is attempted for melt spinnability in its neat and blended form TPS/PLA (70/30) with the intention of checking the possibility of melt spinning. The results from characterization of the prepared biopolymers show that thermal analysis of neat TPS does not reveal clear thermal transitions, glass transition (T g), and melting (T m), in the second heating curve, rather it influenced crystallization behavior of PLA as seen from differential scanning calorimetry result and degradation temperature (T d) was found to be in the range of 296–352°C from thermogravimetric analysis showing that addition of PLA improved thermal stability of TPS. Morphology analysis with AFM images revealed the presence of granular starch in neat TPS and phase separation in TPS/PLA blends with finer phase distribution in the presence of additives. Fourier transform infrared spectroscopy result shows the interaction between starch, glycerol, and PLA showing the effect of thermoplasticization of starch which brings rupture or weakening of the strong glycosidic bonds in between starch molecules and interaction between TPS and PLA as it can be seen from peak shift and peak intensity. The melt spinning trials show the possibility of melt spinning TPS-based biopolymers into fibers even with higher content of TPS as well as neat TPS giving an insight and motivation for more research engagement. The melt-spun fibers were found to have a diameter in the range of 160.0–117.0 μm. However, additional experiments and investigations are required to improve the mechanical and other properties of the fibers.

The Role of WO3 Nanoparticles on the Properties of Gelatin Films.

Gelatin films are very versatile materials whose properties can be tuned through functionalization with different systems. This work investigates the influence of WO3 nanoparticles on the swelling, barrier, mechanical, and photochromic properties of gelatin films. To this purpose, polyvinylpirrolidone (PVP)-stabilized WO3 nanoparticles were loaded on gelatin films at two different pH values, namely, 4 and 7. The values of swelling and solubility of functionalized films displayed a reduction of around 50% in comparison to those of pristine, unloaded films. In agreement, WO3 nanoparticles provoked a significant decrease in water vapor permeability, whereas the decrease in the values of elastic modulus (from about 2.0 to 0.7 MPa) and stress at break (from about 2.5 to 1.4 MPa) can be ascribed to the discontinuity created by the nanoparticles inside the films. The results of differential scanning calorimetry and X-ray diffraction analysis suggest that interaction of PVP with gelatin reduce gelatin renaturation. No significant differences were found between the samples prepared at pH 4 and 7, whereas crosslinking with glutaraldehyde greatly influenced the properties of gelatin films. Moreover, the incorporation of WO3 nanoparticles in gelatin films, especially in the absence of glutaraldehyde, conferred excellent photochromic properties, inducing the appearance of an intense blue color after a few seconds of light irradiation and providing good resistance to several irradiation cycles.

Expanding the Frontiers of nail product evaluation: Novel application of differential scanning calorimetry (DSC) for assessing crosslinking density and predicting nail brittleness and flexibility.

While modern industry advancements have expanded nail beautification options, scientific literature primarily focuses on nail biology and medicine, with limited attention on cosmetic treatments. This study aimed to investigate human nail denaturation properties, including gender impact, blending nails to enlarge the sample pool, nail sensitization through bleaching, and active effectiveness testing. The objective was to understand the DSC and bending fatigue relationship, and define the consumer relevance of the DSC test. Nail clippings were collected from adult female and male volunteers. The wet DSC was employed to validate sample preparation, explore the effects of gender, and assess the potential of using blended nails for claims substantiation testing. Nails were sensitized through bleaching using hydrogen peroxide. The effects were confirmed through DSC and nail flexure tests. Furthermore, the ability of actives to address concerns related to nail softness and brittleness was assessed using these techniques. The results confirmed the viability of equilibrating nails in water for up to 14 h as a standardized testing method. The denaturation temperature results were independent of gender and suitable for claims substantiation testing. Blending nails from different sources did not yield significant variations in denaturation properties. A preliminary study suggested that cadaver nails should be used with caution because they exhibited differences in denaturation temperature, influenced by the sampling location. Bending fatigue tests highlighted the significance of humidity, with higher humidity conditions (80%) enhancing nail flexibility and providing better resolution for claims substantiation. Sensitizing the nails with hydrogen peroxide induced alterations in both DSC and bending fatigue results. Proof-of-principle studies demonstrated an elevation in denaturation temperature and a decrease in the number of cycles to break, indicating a nail-hardening effect when formaldehyde was applied. The use of a nail softener led to an enhancement in nail fatigue resistance due to a notable reduction in nail crosslinking density. The measurement of crosslinking density proved to be a sensitive tool for assessing the effects of cosmetic treatments on nails, particularly in predicting outcomes related to nail brittleness and flexibility.

Potential of polyphenols from Ligustrum robustum (Rxob.) Blume on enhancing the quality of starchy food during frying.

The increasing concerns about health have led to a growing demand for high-quality fried foods. The potential uses of Ligustrum robustum (Rxob.) Blume, a traditional tea in China, as natural additives to enhance the quality of starchy food during frying was studied. Results indicated that L. robustum polyphenols extract (LREs) could improve the quality of fried starchy food, according to the tests of color, moisture content, oil content, texture property, and volatile flavor. The in vitro digestion results demonstrated that LRE reduced the final glucose content from 11.35±0.17 to 10.80±0.70mmol/L and increased the phenolic content of fried starch foods from 1.23±0.04 to 3.76±0.14mg/g. The appearance and polarizing microscopy results showed that LRE promoted large starch bulges on the surface of fried starchy foods. Meanwhile, X-ray diffraction results showed that LRE increased the intensity of characteristic diffraction peak of fried starch with a range of 21.8%-28%, and Fourier transform infrared results showed that LRE reduced the damage to short-range order structure of starch caused by the frying process. In addition, LRE increased the aggregation of starch granules according to the SEM observation and decreased the enthalpy of starch gelatinization based on the differential scanning calorimetry results. The present results suggest that LREs have the potential to be utilized as a natural additive for regulating the quality of fried starchy food in food industries. PRACTICAL APPLICATION: The enhancement of L. robustum polyphenols on the quality of starchy food during frying was found, and its mechanisms were also explored. This work indicated that L. robustum might be used as a novel economic natural additive for producing high-quality fried foods.