CLSM Images Research Articles

Influence of amyloid fibril length and ionic strength on WPI-based fiber-hydrogel composites: Microstructural, rheological and water holding properties

One of the possible advantages of protein fibers in composites is that they can interact with the continuous gel matrix as active fillers at neutral pH. This study aimed to investigate the impacts of short (SAF) and long amyloid fibrils (LAF) and ionic strength (0–150 mM NaCl) on the whey protein isolate (WPI)-based fiber-hydrogel composites. The water holding capacity of the composite gels more depended on the gel coarseness rather than their elasticity. Significant differences were observed between the rheological data of the SAF-WPI and LAF-WPI composites, and the maximum elastic modulus (G′) was achieved at 100 mM NaCl where the LAF-WPI composites outperformed the SAF-WPI ones in enhancing G′ and hardness. Nevertheless, the elasticity and hardness of the composites dramatically dropped at 150 mM NaCl due to the change in the gel microstructure from fine strand to particulate, according to CLSM and SEM images. Interestingly, the trend in average particle size changed at 150 mM NaCl for the SAF- and LAF-WPI soluble aggregates compared to the WPI soluble aggregates. The effects of amyloid fibril and NaCl concentration on the protein aggregates as the initial building blocks of the gel were confirmed by size exclusion chromatography. These results indicated that the properties of composite gel were related to the balance between aggregate creation and the development of cross-links between them during gelation. The findings of the current study could be exploited to predict the functional behavior of globular protein gels containing amyloid fibrils with different lengths at various NaCl concentrations.

Boron-containing coating yields enhanced antimicrobial and mechanical effects on translucent zirconia

ObjectivesTo evaluate the mechanical and antimicrobial properties of boron-containing coating on translucent zirconia (5Y-PSZ). Methods5Y-PSZ discs (Control) were coated with a glaze (Glaze), silver- (AgCoat), or boron-containing (BCoat) glasses. The coatings' antimicrobial potential was characterized using S. mutans biofilms after 48 h via viable colony-forming units (CFU), metabolic activity (CV) assays, and quantification of extracellular polysaccharide matrix (EPS). Biofilm architectures were imaged under scanning electron and confocal laser scanning microscopies (SEM and CLSM). The cytocompatibility was determined at 24 h via WST-1 and LIVE&DEAD assays using periodontal ligament stem cells (PDLSCs). The coatings' effects on properties were characterized by Vickers hardness, biaxial bending tests, and fractography analysis. Statistical analyses were performed via one-way ANOVA, Tukey's tests, Weibull analysis, and Pearson's correlation analysis. ResultsBCoat significantly decreased biofilm formation, having the lowest CFU and metabolic activity compared with the other groups. BCoat and AgCoat presented the lowest EPS, followed by Glaze and Control. SEM and CLSM images revealed that the biofilms on BCoat were thin and sparse, with lower biovolume. In contrast, the other groups yielded robust biofilms with higher biovolume. The cytocompatibility was similar in all groups. BCoat, AgCoat, and Glaze also presented similar hardness and were significantly lower than Control. BCoat had the highest flexural strength, characteristic strength and Weibull parameters (σF: 625 MPa; σ0: 620 MPa; m = 11.5), followed by AgCoat (σF: 464 MPa; σ0: 478 MPa; m = 5.3). SignificanceBCoat is a cytocompatible coating with promising antimicrobial properties that can improve the mechanical properties and reliability of 5Y-PSZ.

Multifunctional nucleoside-AIEgens bearing quaternary ammonium cationic for reversible response, bioimaging, and antibacterial

A multifunctional nucleoside-based AIEgens sensor (TPEPy-dU) was constructed for visual screening of Hg2+, determine to the reversible response of Fe3+ and biothiols, and applied for cell imaging, and drug-free bacterial killing. The TPEPy-dU displayed 10-folds fluorescence enhancement at 540 nm of emission in response to trace Hg2+ ions with 10 nM of LOD, which can be immediately quenched by adding Fe3+ or GSH/Cys-containing sulfhydryl groups. Moreover, their bacterial staining efficiency closely correlates with their antibacterial efficacy as they demonstrated comparatively higher antibacterial activity against Gram-positive bacteria than Gram-negative bacteria. The drug-free antibacterial results involved the stating prominent surface damages at the sites of interactions between bacterial cells and TPEPy-dU that were further verified by CLSM and SEM images. It can be applied as a potential fluorescent agent to explore the related antibacterial mechanisms for treating and monitoring bacterial infections in vivo due to their nontoxic nature. Compared with conventional sensors and antibacterial therapies, these findings elevated the synthetic strategies of fluorescent probes and represented an advanced antibacterial agent wearing quaternary ammonium cationic with low resistance in clinical diagnosis.

Multi-functional epoxides cross-linked collagen sponges for tissue engineering scaffolds

With the efficient cross-linking abilities and the flexible regulation abilities to the performances of cross-linked products, the multi-functional aliphatic epoxides were once widely used to cross-link the collagen-based materials in the last century. In present work, the multi-functional epoxides were used to construct and cross-link collagen sponges for tissue engineering scaffolds, which was hoped to board the theoretical system of epoxides and explore their potentials for modern applications. The bi- to tetra-functional epoxides were used to cross-link collagen solutions and establish the gel-like precursors, then using freeze-drying to form the final sponges. The SEM observed that the sponges had shown regular porous structures with a wide range of pore sizes from 160 to 440 μm. The sponges had presented the resistance to enzymatic degradation, shape-remaining ability, and reversible compressibility in aqueous environments, which all could be regulated through the functionalities of epoxides. The regulation abilities of multi-functional epoxides on the performances of sponges had been mainly achieved through the cross-linking degrees that the higher functionality of epoxides would bring higher cross-linking degree. Such higher cross-linking degrees could enhance the elastic behaviors of gel-like precursors, and improve the compressive strengths and thermal stabilities of sponges. Nevertheless, the multi-functional epoxides had barely affected the safety of collagen sponges at the cellular level according to the results of CCK8 assay and the SEM and CLSM images of L929 fibroblasts cultured on the cross-sections of sponges.Graphical abstract

Effects of microwave on the structural and emulsifying properties and interfacial properties of oxidized soybean protein aggregates.

This research explored microwave treatment impact on the structuro-functional aspects of oxidized soy protein aggregates (OSPI). Data showed that oxidative treatment promoted the formation of high molecular weight aggregates through hydrophobic interactions, thereby disrupting the structure of natural soy protein isolates (SPI). Microwave treatment for an appropriate time (≤30s) caused the molecular structure of OSPI to open up and reduction in molecular weight and disulfide bond content, while absolute zeta potential increased. These modifications increased emulsifying capacity of OSPI, as well as the interfacial adsorption of protein. Longer microwave treatment times (>30s) caused OSPI to exhibit a tendency to aggregate in TEM and CLSM images. It indicated the appropriate microwave electromagnetic field effect and microwave heating effect could coordinatively regulate soy protein functional properties by modifying their aggregation behavior. The results provided new ideas for reducing resource waste, and further expanding soy protein application in the food industry.

Monovalent Salt and pH-Stimulated Gelation of Scallop (Patinopecten yessoensis) Male Gonad Hydrolysates/κ-Carrageenan.

The gelation of scallop Patinopecten yessoensis male gonad hydrolysates (SMGHs) and κ-carrageenan (KC) subjected to pH (2-8, 3-9) and NaCl/KCl stimuli-response was investigated. SMGHs/KC gels subjected to a NaCl response exhibited an increasing storage modulus G'from 2028.6 to 3418.4 Pa as the pH decreased from pH 8 to 2, with corresponding T23 fluctuating from 966.40 to 365.64 ms. For the KCl-treated group, SMGHs/KC gels showed an even greater G' from 4646.7 to 10996.5 Pa, with T23 fluctuating from 622.2 to 276.98 ms as the pH decreased from 9 to 3. The improved gel strength could be ascribed to the blueshift and redshift of hydroxyl groups and amide I peaks, enhanced enthalpy and peak temperature, and gathered characteristic diffraction peaks from SMGHs, KC, NaCl, and KCl. The CLSM and cryo-SEM images further reflected that SMGHs/KC gels showed more flocculation formation and denser and more homogeneous networks with smaller pore sizes in more acidic domains, especially when subjected to the KCl response. This research gives a theoretical and methodological understanding of the construction of salt- and pH-responsive SMGHs/KC hydrogels as novel functional soft biomaterials applied in food and biological fields.

Anammox granule destruction and reconstruction in a partial nitrification/anammox system under hydroxylamine stress

Nitrite oxidizing bacteria (NOB) outcompeting anammox bacteria (AnAOB) poses a challenge to the practical implementation of the partial nitrification/anammox (PN/A) process for municipal wastewater. A granules-based PN/A bioreactor was operated for 260 d with hydroxylamine (NH2OH) added halfway through. qPCR results detected the different amounts of NOB among granules and flocs and the dynamic succession during operation. CLSM images revealed a unique layered structure of granules that NOB located inside led to the inhibition effect of NH2OH delayed. Besides, the physical and morphological characteristics revealed that anammox granules experienced destruction. AnAOB took the broken granules as an initial biofilm aggregate to reconstruct new granules. RT-qPCR and high throughput sequencing results suggested that functional gene expression and community structure were regulated for the AnAOB metabolism process. Correspondingly, the rapid proliferation (0.52 → 1.99%) of AnAOB was realized, and the nitrogen removal rate achieved a nearly quadruple improvement (0.21 → 0.83 kg-N/m3·d). This study revealed that anammox granules can self-reconstruct in the PN/A system when granules are disintegrated under NH2OH stress, broadening the feasibility of applying PN/A process.

Using Antimicrobial Photodynamic Therapy with Ultrasound Devices and Bioactive Glasses as a Combined Approach for Treating Dentin Caries Lesions.

Novel approaches for caries lesion removal and treatment have been proposed. This study evaluates the combined use of an experimental ultrasound, aPDT (antimicrobial photodynamic therapy) and bioactive glasses on the removal, decontamination and remineralization of dentin caries lesions. A biological model created with a duo species biofilm (Streptococcus mutans and Lactobacillus acidophilus) was used for the development of a caries-like lesion over the dentin for 7 days. Bovine dentin specimens (4 × 4 × 2 mm) were randomized according to the following caries removal techniques: bur (BUR) or ultrasound (ULT), decontamination (with or without aPDT) and remineralization materials (45S5 or F18 bioactive glasses). The following different groups were investigated: caries lesion (control); sound dentin (control); BUR; BUR + aPDT; ULT; ULT + aPDT; BUR + 45S5, BUR + F18; ULT + 45S5; ULT + F18; BUR + aPDT + 45S5; BUR + aPDT + F18; ULT + aPDT + 45S5; and ULT + aPDT + F18. Transverse microradiography (TMR), cross-sectional microhardness (CSH), FT-Raman spectroscopy and confocal microscopy (CLSM) were performed. A two-way ANOVA and Tukey's test were used (α = 0.05). (3) Results: The TMR revealed a lesion depth of 213.9 ± 49.5 μm and a mineral loss of 4929.3% vol.μm. The CSH increases as a function of depth, regardless of the group (p < 0.05). Removal with BUR (24.40-63.03 KHN) has a greater CSH than ULT (20.01-47.53 KHN; p < 0.05). aPDT did not affect the CSH (p > 0.05). No difference was observed between 45S5 or F18 (p > 0.05), but a change was observed for ULT (p > 0.05). The FT-Raman shows no differences for the phosphate (p > 0.05), but a difference is observed for the carbonate and C-H bonds. The CLSM images show that aPDT effectively inactivates residual bacteria. A combination of ULT, aPDT and bioactive glasses can be a promising minimally invasive treatment.

Pickering emulsion stabilized by conjugated sodium caseinate-ascorbic acid nanoparticles: Synthesis and physicochemical characterization

This study investigated the effect of sodium caseinate (SC)-ascorbic acid (AA) interaction under thermal (as a Maillard reaction) treatment on the physicochemical properties of the SC-AA colloidal particles, as well as, the physical and oxidative stability of the prepared Pickering emulsion (PE) using colloidal particles as an aqueous phase with the volumetric ratio of 50:50 water and oil. The stable colloidal suspensions were obtained when the concentration of SC-AA solution was set at 10 and 1 mg/mL for SC and AA, respectively. The fluorescence and FT-IR results showed strong hydrophobic interaction in SC-AA complex, but after heat treatment of SC and AA (HSC-AA), the covalent Schiff base type bond formed. In the HSC-AA sample, the percentage of free amino group reduction (∼32%) confirmed the Maillard reaction occurrence, and the results of SDS-PAGE showed cross-linking between SC particles. A significant decrease in interfacial tension was observed in samples containing AA, which reached the lowest value in HSC-AA (6.5 mN/m). Also, the wettability of HSC-AA increased based on a three-phase contact angle analysis to θ ∼82°. In the case of physical stability, while SC, SC-AA, and HSC samples could not stabilize the PE, the HSC-AA showed the best physical stability for more than 90 days at 4 °C and 7 days at 37 °C. CLSM images showed HSC-AA particles were located around the oil droplet. Based on TBARS results, the value of advanced oxidation product was the lowest for HSC-AA stabilized PE, indicating the protective effect of HSC-AA solid particles against lipid oxidation. This research confirmed the HSC-AA effectiveness as a solid particle stabilizer for PE, especially in reduced fat formulations. These results are valuable due to the common use of SC and AA as food-grade additives.

Fabrication and characterization of food-grade pea protein-ascorbic acid nanoparticles-stabilized Pickering emulsion

In this study, modified pea proteins (PP) were prepared by heat treatment, ultrasound, adjusting the pH to 9, and the addition of ascorbic acid (AA) to stabilize the Pickering emulsion (PE) with a 50% volume fraction of corn oil. The solubility of PP after different treatments was higher in all treatments than in the native state. FTIR and SDS-PAGE results confirmed that a covalent bond (Maillard reaction) was formed between PP and AA, which occurred more strongly in the heat-treated suspensions. The nanoparticles produced from ultrasonication of PP and the PP/AA complexes were able to stabilize the emulsion with a high volume fraction of oil as novel Pickering emulsifiers. In ultrasonicated PP and PP/AA complexes, the reduction of interfacial tension and particle size and increase of contact angle caused a significant improvement in the physical stability of the PE, which can be the result of regular placement of protein particles at the water-oil interface. The treatment corresponds to highly stable PE, heat-treated PP in the presence of AA in alkaline conditions (HPP.AA.pH), increased the contact angle of PP from ∼ 42 to 77, and decreased interfacial tension from ∼ 25 to 14. These PEs showed high physical and oxidative stability. According to CLSM images, the type of PE was oil in water, and PP particles surrounded the oil droplets. The results of this research could be effective in developing PP-based low-fat formulations with improved oxidative stability by utilizing different treatments, including ultrasonic treatment and/or complex formation between PP and AA.

Pickering stabilizing capacity of Plasma-treated Grass pea protein nanoparticles

The Pickering stabilizing capacity of Grass pea protein isolate (GPPI) was investigated as a function of cold plasma treatments (9.4 and 18.6 kVpp, 300 or 600 s) and particle concentrations (25, 50, and 75 mg/mL). Plasma-treated Grass pea protein (GPPIPT) particles had a lower contact angle with oil, and an ability to form smaller oil droplets than GPPI particle, indicating that cold plasma treatment improved their interfacial properties. GPPIPT-stabilized emulsions were more flocculated and effective at reducing oil droplet coalescence than GPPI particles. GPPIPT-300s18.6-stabilized emulsion had the best coalescence stability, with a uniform and denser steric barrier on the surface of droplets, as confirmed by CLSM images. GPPIPT-600s18.6-stabilized emulsion showed greater creaming stability at high particle concentrations, which was linked to smaller droplet sizes and formed a complex microstructure for the emulsion. This study provides a new method to improve Pickering stabilizing capacity of proteins through cold plasma treatment.

Methodology for Collecting and Aligning Correlative SEM, CLSM and LOM Images of Bulk Material Microstructure to Create a Large Machine Learning Training Dataset.

Methodology for Collecting and Aligning Correlative SEM, CLSM and LOM Images of Bulk Material Microstructure to Create a Large Machine Learning Training Dataset.

Application of Persimmon Pectin with Promising Emulsification Properties as an Acidified Milk Drinks Stabilizer.

The present study aimed to evaluate the capability of persimmon pectin (PP) as a stabilizer for acid milk drinks (AMDs) compared with commercial high-methoxyl pectin (HMP) and sugar beet pectin (SBP). The effectiveness of pectin stabilizers was assessed by analyzing particle size, micromorphology, zeta potential, sedimentation fraction, storage, and physical stability. Results of CLSM images and particle size measurements showed that PP-stabilized AMDs had smaller droplet sizes and more uniform distributions, indicating better stabilization potential compared with the HMP- and SBP-stabilized AMDs. Zeta potential measurements revealed that the addition of PP significantly increased the electrostatic repulsion between particles and prevented aggregation. Moreover, based on the results of Turbiscan and storage stability determination, PP exhibited better physical and storage stability compared with HMP and SBP. The combination of steric repulsion and electrostatic repulsion mechanisms exerted a stabilizing effect on the AMDs prepared from PP. Overall, these findings suggest that PP has promising potential as an AMD stabilizer in the food and beverage industry.

Sequential two-stage extraction of Xanthoceras sorbifolia seed oil using supercritical CO2 and CO2-expanded ethanol

A new method of seed oil extraction from X. Sorbifolia was developed using a two-stage process with supercritical CO2 (SC-CO2) and CO2-expanded ethanol (CXE). The BIC model was employed to optimize the extraction process. During the SC-CO2 extraction stage, the CLSM imaging showed rapid release of EAO from the broken cells at the edge of the particles with an oil yield of 74.11% after 4 h. The follow-up CXE extraction at 10 MPa, 333 K, and 1.5 kg/h, with a CO2 molar fraction of 0.5 resulted in 68% broken cells by SEM imaging, and obtained 18.42% of remaining HAO, with a total oil yield of 92.53%. The whole process was completed in 60% less time compared to the Soxhlet method. Lipid composition analysis found a small amount of fatty acid ethyl ester in CXE oil and a higher content of functional fatty acid nervonic acid at 4.12%.

Development of a bioactive dentin adhesive resin modified with magnesium-doped synthetic hydroxyapatite crystals

The aim is to evaluate the development of an experimental multi-mode/Universal resin-based dentin adhesive modified with synthetic Mg2+ doped hydroxyapatite crystals (HAp) having self-remineralization and antibiofilm properties. HAp doped with Mg2+ was prepared by the precipitation method. Experimental adhesives were subjected to degree of conversion and X-ray diffraction test for size and crystal structure. Bond strength was tested, and electron microscopy (SEM/TEM) imaging of resin-dentin interface was done along with nanoleakage, nanoindentation, confocal and Raman analyses. S. mutans was analysed using CLSM images against modified adhesive specimens. Nucleating abilities within the resin-dentin specimens are determined by measuring Ca2+. Alkaline phosphatase, Runx2, and Ocn transcripts are amplified using quantitative polymerase chain reaction (q-PCR). A calcium assay is performed to quantify level of mineralisation. When compared to control adhesives, the 0.5% Hap/Mg2+ containing experimental dentin adhesive demonstrated improved interaction with dentin. The preservation of uniform intact hybrid layer with the absence of nanoleakage indicated dentin bond integrity with 0.5% HAP/Mg2+ modified adhesive. Self-remineralization and antibiofilm potentials are supported.

Application Prospects of FTIR Spectroscopy and CLSM to Monitor the Drugs Interaction with Bacteria Cells Localized in Macrophages for Diagnosis and Treatment Control of Respiratory Diseases.

Visualization of the interaction of drugs with biological cells creates new approaches to improving the bioavailability, selectivity, and effectiveness of drugs. The use of CLSM and FTIR spectroscopy to study the interactions of antibacterial drugs with latent bacterial cells localized in macrophages create prospects to solve the problems of multidrug resistance (MDR) and severe cases. Here, the mechanism of rifampicin penetration into E. coli bacterial cells was studied by tracking the changes in the characteristic peaks of cell wall components and intracellular proteins. However, the effectiveness of the drug is determined not only by penetration, but also by efflux of the drugs molecules from the bacterial cells. Here, the efflux effect was studied and visualized using FTIR spectroscopy, as well as CLSM imaging. We have shown that because of efflux inhibition, eugenol acting as an adjuvant for rifampicin showed a significant (more than three times) increase in the antibiotic penetration and the maintenance of its intracellular concentration in E. coli (up to 72 h in a concentration of more than 2 μg/mL). In addition, optical methods have been applied to study the systems containing bacteria localized inside of macrophages (model of the latent form), where the availability of bacteria for antibiotics is reduced. Polyethylenimine grafted with cyclodextrin carrying trimannoside vector molecules was developed as a drug delivery system for macrophages. Such ligands were absorbed by CD206+ macrophages by 60-70% versus 10-15% for ligands with a non-specific galactose label. Owing to presence of ligands with trimannoside vectors, the increase in antibiotic concentration inside macrophages, and thus, its accumulation into dormant bacteria, is observed. In the future, the developed FTIR+CLSM techniques would be applicable for the diagnosis of bacterial infections and the adjustment of therapy strategies.

Development and mechanical properties of soy protein fibrils-chitin nanowhiskers complex gel

To enrich the use of protein-polysaccharide complex gel as texture assistance, we introduced a soy protein fibrils-chitin nanowhiskers complex gel system. Firstly, a stable positively charged chitin nanowhiskers (CNW) suspension and amyloid-like soy protein fibrils (SPF) were fabricated. We found that the self-assembled SPF and CNW formed complex with each other at pH 5.0–8.0 due to attractive interactions caused by their carrying opposite electrical charges. Then, the MTGase-induced SPF-CNW complex gel were formed and investigated by instrumental analysis. The results showed that the presence of CNW significantly increased the β-Sheet structure in complex gel and the rheological modules of complex gel were pH-dependent and showing G' > G" at all pHs. The SPF-CNW complex gel showed a strong and elastic textural property during compression test at pH 6.0. Meanwhile, the frequency scan showed that the SPF-CNW system is less dependent on the frequency and belonged to the typical physical gel. According to the results of SEM and CLSM images, the SPF, CNW and complex gel presented spherical shape, rod shape and linear alignment microstructure, respectively. We inferred that the CNW provided a framework for gel formation and introduced rigidity to the SPF gel. Thanks to the attractive interactions, the SPF molecules were attached to the growth of CNW to form a longer fiber structure. After the gelation process, the aggregates further interacted with each other and finally form complex gel with linear, ordered and compact microstructure.

Phase Inversion of Pickering Emulsions Induced by Interfacial Electrostatic Attraction

Phase inversion of Pickering emulsions from water-in-oil (W/O) to oil-in-water (O/W) is achieved by the formation of an interfacial particle bilayer using negatively charged and positively charged particles dispersed in water and oil, respectively, before emulsification. A mechanism based on electrostatic attraction across the toluene-water interface is proposed and verified by systematic investigation of the parameters that affect the surface charge of negatively charged particles such as pH and salt concentration. Cationic silica-FITC particles (600 nm) can be dispersed in toluene and stabilize W/O emulsions alone; phase inversion of this emulsion can be induced by the addition of anionic silica-RB particles in the aqueous phase at a concentration of 1.0 wt % or above. It is revealed that silica-RB particles of a smaller size (100 nm) can induce emulsion phase inversion at a much lower concentration (0.4 wt %) and an interfacial particle bilayer is clearly revealed by CLSM and SEM images. By tuning the surface charge density of silica-RB particles, the electrostatic attraction mechanism leading to the formation of the interfacial particle bilayer is confirmed and emulsion stability can be tuned as demonstrated by osmotic pressure enhancement results obtained from centrifugation.

Accelerated mineralization kinetics in children with osteogenesis imperfecta type 1.

Not much is known about the time course of mineralization in newly formed bone from healthy individuals nor in patients with bone disease. To investigate the early phase of mineral accumulation in human bone, we measured the mean mineralization content between double fluorescence labels (CaYoung) with quantitative backscattered electron imaging (qBEI) in human transiliac biopsy samples. Fluorescent labels for histomorphometric evaluation were administered over two 2-day periods separated by a 10-day-free interval, 4–5 days before biopsy procedure. We compared n = 19 children with osteogenesis imperfecta type I (OI, 6 girls/13 boys, age-range 2.2–14.1 years) with both a reference group of n = 38 healthy children (REF, 24 girls/14 boys, age-range 1.5–20.9 years) and an age-matched subgroup ( n = 17) of the latter (CON, 5 girls/12 boys, age-range 2.0–14.7 years). We observed significantly higher levels of CaYoung in OI type I compared to CON and REF in both cortical bone (Ct.CaYoung, +8.3 % and +7.0 %, respectively) and cancellous bone (Cn.CaYoung, +6.5 % and +4.9 %, all p < 0.001). When comparing cortical and cancellous compartments intra-individually, we found a significantly higher Cn.CaYoung than Ct.CaYoung in REF (2.3 ± 2.9 %, p < 0.001), but not in the OI group (0.6 ± 1.6 %, not significant). In the REF group, n = 7 samples also contained double labels in primary woven bone (which is deposited at the external cortex during growth/lateral drift of the iliac crest). This primary woven bone in REF had a higher CaYoung than secondary osteonal bone (4.9 ± 2.7 %). Our findings suggest that bone in OI has an accelerated mineral accumulation compared to healthy bone. This is reflecting the overall increased bone mineralization in OI as reported previously, and indicates that the higher levels of mineralization than those seen in healthy individuals are already achieved in OI type I early after onset of mineralization. • We measured mineralization kinetics by the combination of qBEI and CLSM imaging. • The mineral content of bone between the double labels (CaYoung) was analyzed. • CaYoung was increased in young patients with OI compared to healthy children. • In healthy children but not in OI, CaYoung was higher in spongiosa than in cortex.

Impact of biopolymer-surfactant interactions on the particle aggregation inhibition of β-carotene in high loaded microcapsules: Spontaneous dispersibility and in vitro digestion

The particle aggregation of β-carotene has been a challenge for the development of powdery microcapsules with a high loading. Herein, solvent-free β-carotene high loaded microcapsules based on the wet-milling technique were fabricated by using a complex stabilizer composed of octenyl succinic anhydride modified starch (OSA-starch) and tea saponin (TS). The influence of biopolymer-surfactant interactions on the particle aggregation inhibition of β-carotene in the microcapsules was investigated. The particle size distribution, micromorphology, redispersibility and in vitro digestion of the microcapsules were altered by regulating the addition sequence and the mass ratio of both stabilizers. The optimized β-carotene microcapsule presented a small particle size after rehydration (275.1 nm) with the high encapsulation efficiency and loading capacity (99.04% and 18.87%, respectively). As analyzed by FTIR and XRD, the hydrogen bonding and hydrophobic interactions between β-carotene and wall materials were involved in the amorphization of β-carotene. SEM and CLSM images jointly verified that the biopolymer-surfactant complex retarded the expansion of the microcapsules, and the dents on the surface of microcapsules facilitated the moisture infiltration during rehydration. Moreover, the wall material composition of microcapsules further affected the bioaccessibility of β-carotene during the simulated digestion, and the bioaccessibility of β-carotene was increased from 2.73% to 15.97% due to the enhanced micellization and transport capacity of β-carotene. •Competitive adsorption and hydrophobic effects of wall materials occurred on the particle surface. •The biopolymer-surfactant complexation prevented β-carotene from reaggregation. •The surface irregularity contributed to the spontaneous dispersibility of microcapsules. •The bioaccessibility of β-carotene was improved by adding TS into wall materials.