Cycles Of Centrifugation Research Articles

Formulation of self-nanoemulsifying drug delivery system (SNEDDS) of combined 70% ethanolic of Begonia medicinalis herbs and Moringa oleifera leaves

Background: Benalu batu (Begonia medicinalis) and kelor leaves (Moringa oleifera) are empirically used as alternative therapies by people in Central Sulawesi to maintain their health. Our previous research showed that the combination of these two plant extracts possessed an immunomodulatory activity. Self-Nanoemulsifying Drug Delivery System (SNEDDS) formulation was performed to improve the extract's bioavailability, solubility and stability. Objective: This study aims to formulate and characterise SNEDDS preparations of combined ethanolic extract of B. medicinalis herbs and M. oleifera leaves and further test its stability. Method: SNEDDS formulation was started by screening for proper oil, surfactant, and co-surfactant. The formula was then optimised using a ternary phase diagram and characterisation. The stability test was performed using centrifugation, heating-cooling, and freeze-thaw cycles. Results: The optimal SNEDDS formula consists of isopropyl myristate (10%), tween 80 (50%) and propylene glycol (40%). The characterisation values obtained were: Transmittance value 83.785 ± 0.275%, particle size 18.666 ± 0.208 nm, polydispersity index 0.664 ± 0.0085, and zeta potential -39.20 ± 0.2 mV. The formula was stable during three stability evaluation tests. Conclusion: The optimal formula met the SNEDDS characteristics requirements and showed good stability.

Differences between first- and second-generation autologous platelet concentrates.

Autologous platelet concentrates (APCs) applied alone or combined with other biomaterials are popular bioactive factors employed in regenerative medicine. The main biological rationale of using such products is to concentrate blood-derived growth factors and cells into the wound microenvironment to enhance the body's natural healing capacity. First-generation APC is represented by platelet-rich plasma (PRP). While different protocols have been documented for PRP preparation, they overall consist of two cycles of centrifugation and have important limitations related to the use of an anticoagulant first and an activator afterward, which may interfere with the natural healing process and the release of bioactive molecules. The second generation of platelet concentrates is represented by leukocyte and platelet-rich fibrin (L-PRF). L-PRF protocols involve a single centrifugation cycle and do not require the use of anticoagulants and activators, which makes the preparation more straight forward, less expensive, and eliminates potential risks associated with the use of activators. However, since no anticoagulant is employed, blood undergoes rapid clotting within the blood collection tube; hence, a timely management of L-PRF is crucial. This review provides an overview on the most documented protocols for APC preparations and critically discusses the main differences between first- and second-generation APCs in terms of cell content, protein release, and the formation of a 3D fibrin network. It appears evident that the inconsistency in reporting protocol parameters by most studies has contributed to conflicting conclusions regarding the efficacy of different APC formulations and has significantly limited the ability to interpret the results of individual clinical studies. In the future, the use of a standardized classification system, together with a detailed reporting on APC protocol parameters is warranted to make study outcomes comparable. This will also allow to clarify important aspects on the mechanism of action of APCs (like the role of leukocytes and centrifugation parameters) and to optimize the use of APCs in regenerative medicine.

Hollow-fibre infection model: adaptations for the culture and assessment of fastidious organisms.

The hollow-fibre infection model (HFIM) is a valuable in vitro platform for emulating antimicrobial drug pharmacokinetic profiles. Despite its potential, standardized protocols for HFIM operation, especially concerning fastidious organisms, are lacking. This study addresses this gap by examining challenges in culturing Pasteurella multocida and Actinobacillus pleuropneumoniae, two fastidious organisms, in the HFIM. Our findings reveal effective strategies to prevent system clogging, involving multiple freeze-thaw cycles of horse blood, centrifugation and cell straining to enhance the clarity of the Mueller-Hinton fastidious medium defined by the European Committee on Antimicrobial Susceptibility Testing and Clinical and Laboratory Standards Institute. Additionally, we propose that the provision of a CO2 atmosphere, along with the utilization of gas-permeable tubing and gas vent filters, significantly facilitates the growth of fastidious organisms. Remarkably, both P. multocida and A. pleuropneumoniae were sustained for a period of up to 10 days under these optimized conditions. This study provides crucial insights into the modifications necessary to successfully culture fastidious organisms in the HFIM, paving the way for more accurate and representative in vitro models for antimicrobial drug testing. These advancements hold promise for advancing research in the field of antimicrobial pharmacokinetics and efficacy against challenging pathogens.

Deproteinization of Natural Rubber Latex and Its Pale-Colored Thin Films

The non-rubber components present in natural rubber latex can contribute to the dark color of dried films and may cause allergic reactions. This project aimed to develop light-color rubber films with minimal protein contamination. Various additives were incorporated, and a leaching procedure was implemented to address this issue. The evaluation focused on protein content, color changes, and swelling properties of thin natural rubber films. Texapon N70 proved effective as both a latex stabilizer and leaching agent, while Uniphen P-23 served as a preservative. The combined use of these additives facilitated the removal of soluble serum through appropriate incubation, leaching, and centrifugation processes. The introduction of additional centrifugation cycles improved deproteinization and color reduction; however, it led to a loss of rubber mass and an increase in manufacturing costs. Increasing the amount of Texapon N70 and introducing alkali potassium hydroxide (KOH) further enhanced the efficiency of deproteinization and color reduction. The optimal conditions determined in this investigation were as follows: 0.5% w/w Texapon N70, 0.5% w/w KOH, 1% w/w Uniphen P-23, a 60-min incubation period, and a single leaching cycle with distilled water. These conditions resulted in a 90.57 ± 1.20% decrease in protein contamination and a color change (ΔE) of 433.69 ± 20.23. This successful condition can be replicated and scaled up for further applications.

Encapsulation of Concentrated Solution Obtained by Block Freeze Concentration in Calcium Alginate and Corn Starch Calcium Alginate Hydrogel Beads

A model (sucrose and gallic acid) solution was concentrated by block freeze concentration (BFC) at three centrifugation cycles, and the solutions were encapsulated in calcium alginate and corn starch calcium alginate hydrogel beads. Static and dynamic tests determined the rheological behavior, differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FTIR) established thermal and structural properties, and the release kinetics was evaluated under in vitro simulated digestion experiment. The highest efficiency encapsulation value was close to 96%. As the concentrated solution increased in terms of solutes and gallic acid, the solutions were fitted to the Herschel-Bulkley model. Moreover, from the second cycle, the solutions exhibited the highest values of storage modulus (G') and loss modulus (G″), contributing to form a more stable encapsulation. The FTIR and DSC results demonstrated strong interactions between corn starch and alginate, establishing a good compatibility and stability in the bead formation. The kinetic release model under in vitro conditions was fitted to the Korsmeyer-Peppas model, demonstrating the significant stability of the model solutions inside the beads. Therefore, the present study proposes a clear and precise definition for the elaboration of liquid foods obtained by BFC and its incorporation inside an edible material that facilitates the controlled release in specific sites.

Processing Vat Polymerized Triply Periodic Minimal Surface Scaffolds of Hydroxyapatite

Vat polymerization of ceramic slurries offers a means for producing triply periodic minimal surface (TPMS) structures, which are candidates for artificial trabecular bone replacement therapy. However, structures with relevant pore sizes below 500 μm and porosities above 80% push the limits of current ceramic additive manufacturing capabilities. Herein, printing and postprocessing of TPMS structures with features relevant to bone, specifically, pore sizes from 400 to 1,265 μm, porosities over 75%, and wall thicknesses below 200 μm are addressed. The resolution of several key fundamental challenges includes: (a) adhesion to the build plate by starting the first layer with the highest surface area slice, (b) cleaning complex designs with two centrifugation cycles consistently removing 100% of residual slurry, (c) elimination of contamination from heating elements by sintering hydroxyapatite in a tube furnace, and (d) determining differences in firing shrinkage between designs to allow for targeting specified sintered dimensions. The outcome of this work enables the consistent fabrication of hydroxyapatite TPMS scaffolds (gyroid, trifurcating, clover) with high agreement between the computer‐aided design (CAD), printed, and fired designs in 5 mm cubes and cylinder with 8 mm diameter and 20 mm length.

Influence of Centrifugation Cycles of Natural Rubber Latex on Final Properties of Uncrosslinked Deproteinized Natural Rubber.

Natural rubber latex (NRL) is a polymer (blend) extracted from the milky sap of para rubber trees. Due to being a natural biopolymer, NRL contains various proteins that may be allergenic to humans when in skin contact. Attempts have been made to use deproteinized natural rubber (DPNR) instead of impure NRL, and the final properties of these two types of rubber tend to differ. Thus, the correlations between their chemistry and properties are of focal interest in this work. DPNR was prepared by incubating NRL with urea, followed by aqueous washing/centrifugation. The physical, mechanical, and dynamic properties of incubated NRL before and after washing/centrifugation were examined to distinguish its influences from those of incubation with urea. According to the findings, the proteins, phospholipids, and chain entanglements were responsible for natural polymer networks formed in the NR. Although the proteins were largely removed from the latex by incubation, the properties of high ammonia natural rubber (HANR) were still maintained in its DPNR form, showing that other network linkages dominated over those contributed by the proteins. In the incubated latex, the naturally occurring linkages were consistently reduced with the number of wash cycles.

Successful healing of non-healing surgical wound based on the release of platelet-derived growth factors from single donor allogeneic platelet-RICH plasma with one freeze-thaw cycle: a case report after a 1-year follow-up

BackgroundNon-healing surgical wounds is a risk in certain patients. Recently, allogenic plasma-rich-platelet (PRP) is used such as regenerative treatment of different non-healing surgical wounds.PurposeWe explore the potential role of using platelet-derived growth factors from single donor PRP, with a freeze-thaw process, for the treatment of surgical scar ulcer.MethodsWe have used a PRP preparation protocol that involved a single cycle of centrifugation at a mean speed of 2400–2800 rpm of donor blood taken with an apheresis machine.ResultsTo our knowledge, this is the first study using the platelet-derived growth factors (PDGF) from single donor apheresis, with a freeze-thaw process. Four weeks after daily application of al-PRP, the ulcer progressed satisfactorily; at six weeks, the ulcer had healed.ConclusionWe concluded that the healing of a surgical wound observed in our case, is promising and suggests that al-PRP might play a role in treating surgical scar ulcers. This must be confirmed in future studies.

Robust Dual-Biomimetic Titanium Dioxide-Cellulose Monolith for Enrichment of Phosphopeptides.

Metal oxide affinity chromatography (MOAC) is considered to be one of the most effective methods for phosphopeptide enrichment. However, most of the materials used in the method are powder; frequent centrifugation is necessitated during the enrichment process, and potential risks of loss of peptides and materials and clogging of the column employed for liquid chromatography-mass spectrometry (LC-MS) arise. Moreover, the reusability of these materials to achieve sustainability was hardly investigated. To overcome these limitations, herein, inorganic titanium dioxide (TiO2) was coated onto the skeletal surface of the organic cellulose monolith (CM) material with a coral-like structure via a sol-gel method. This produced an organic-inorganic hybrid TiO2-CM material, which contained a combination of organic and inorganic substances, making it mimic the mollusk shell in terms of composition. The prepared TiO2-CM material as monolith exhibited excellent mechanical strength and did not break during the enrichment process; thus, the tedious implementation of multiple centrifugation cycles was prevented, thereby streamlining the experimental procedure and avoiding the loss of peptides and materials. Moreover, a large amount of TiO2 was introduced onto the surface of the CM material, and thus, the resultant TiO2-CM material exhibited a large surface area. As a result, the fabricated TiO2-CM material was successfully applied to the enrichment of phosphopeptides obtained from the tryptic digests of a BSA/β-casein (mass ratio, 500/1) mixture. The results were superior to those achieved for commercial TiO2 beads, confirming that TiO2-CM has excellent selectivity for phosphopeptides and reusability. Furthermore, 9287 unique phosphopeptides derived from the 2661 phosphoproteins were successfully identified from two milligrams of tryptic digests of Hela cell exosomes obtained through five independent replications after enriching using the TiO2-CM material. The results indicated that the material has good application prospects in the analysis of protein phosphorylation. Furthermore, TiO2-CM consists of green and cheap cellulose as the skeleton, and its synthesis process is environment-friendly, simple, and inexpensive.

Synthesis and characterization of nanoemulsion of citronella oil (Cymbopogon Nardus L. Rendle) and its Sunscreen Potential Evaluation

Abstract Citronella (Cymbopogon nardus L. Rendle) essential oil contains active compounds such as antioxidants and has the potential to be developed as a sunscreen. Nanoemulsion is a water and oil dispersion stabilized by a surfactant layer and has a particle size below 100 nm. This study described the formulation, characterization of citronella oil nanoemulsions, and determination of their activity as a sunscreen through the SPF values. The nanoemulsion formulation was made with 3 variations of oil concentration: F1 (1%), F2 (3%), and F3 (5%). The results of the organoleptic test were following the standards which were clear and no phase separation occurred. In addition, the pH value of the 1%, 3%, and 5% prepared nanoemulsions were categorized as safe to be used on the skin. The prepared formulas were categorized as O/W nanoemulsion types. The viscosity values were found to be 12.76, 25.13, and 84.05 cP respectively. Furthermore, the percent transmittance values were 98.4, 98.9, and 99.9%. The particle sizes, respectively, were 9.4 (100%), 10.07 (97%), and 8.96 nm (82.5%). The centrifugation and freeze-thaw cycle tests showed good physical stability. The results of the sunscreen potential test of the 1%, 3%, and 5% citronella oil nanoemulsion showed SPF values of 1.03, 1.13, and 1.14 with %Te values of 77.42, 70.21, and 67.86% respectively, and %Tp values of 95.94, 94.04, and 93.61% respectively. Keywords: Citronella essential oil (Cymbopogon nardus L. Rendle), nanoemulsion, antioxidant, sunscreen, SPF.

Development of Test Cycle for Centrifugal Clutch of CVT Driven Scooters Intended for Urban Traffic Conditions

The present study deals with the development of a test cycle for the centrifugal clutch of continuously variable transmission (CVT) driven scooters. Centrifugal clutch experiences different duty cycles during the usage of scooters in city traffic and highways during its lifetime. Since the friction characteristics of the centrifugal clutch are controlled by acquired factors, it is difficult to predict ideal friction characteristics under all conditions. The wear of friction lining increases due to heat generated in the clutch assembly because of the repeated “stick-slip” phenomena. Therefore, an attempt has been made for developing à new test cycle by keeping the engagement frequency as a reference. Road load data for three different riding conditions have been collected and analyzed. The developed test cycle has been automated on the centrifugal clutch test bench and a new set of clutch liners was tested thoroughly. The surface roughness, thickness, and wear of clutch liners have been observed and evaluated against the field vehicles. For the surface roughness, maximum deviations of 3.74%, 3.36%, and 2.16% have been observed for trailing, middle and leading sections of clutch liners respectively. For the thickness, maximum deviations of 3.06%, 2.59%, and 3.14% have been observed for trailing, middle and leading sections of clutch liners respectively. The developed test cycle demonstrates a good correlation with field use.

The G-Force Conundrum in Platelet-Rich Fibrin Generation

Aim:A force of 400 g at 2700 revolutions per minute (RPM) results in an optimum leukocyte and platelet-rich fibrin (L-PRF). Most of centrifuges with varying characteristics generate a g-force in excess of 700 g at 2700 RPM. In this context, the study explores the effect of the original centrifugation protocol and a modified protocol tailor-made to lower the RPM to generate a g-force of ~ 400 g on platelet concentration, clot size and growth factors release in L-PRF prepared in two different commercially available centrifuges.Materials and Methods:Twenty five subjects each were assigned to the following groups; R1 and R2 where L-PRF was obtained from two laboratory swing-out centrifuges (Remi 8C® and Remi C854®, Mumbai, India), respectively. PRF was obtained from each subject within a group using two protocols; Original (O) protocol: conforming to the original centrifugation cycle (2700 RPM for 12 min) and Modified (M) protocol. Clot size, growth factor estimation, and platelet counts were measured at 20, 40, and 60 min from all the L-PRF clots, respectively.Results:At the third time period (40–60 min), there were no significant differences in clot sizes with the original protocol (P = 0.09), but a highly significant difference was noticed with the modified protocol in both the centrifuges (P = 0.001). Our results showed an increased concentration of vascular endothelial growth factor and epidermal growth factor with modified protocol than with original protocol with both the centrifuges (P = 0.001). By the end of second and third time periods, more platelet concentration was observed with modified protocol than with the original protocol in both the centrifuges (P = 0.001).Conclusion:This study infers that the centrifuge type and relative centrifugal force can affect the quality and quantity of cells and growth factors and an optimum relationship between g-force and RPM should be maintained to obtain L-PRF with adequate cell viability and optimum growth factor release.

Microemulsion for Simulataneous Intransal Delivery of Carbamazepine and Vitamin B6 for Treatment of Epilepsy

<p style="text-align: justify;"><strong>Background: </strong>Status epilepsy is a neurological emergency characterized by severe bouts of seizure. It has been reported that combination of antiepileptic drug with Vitamin supplements reduce the drug resistance and rapid improvement was also observed in epilepsy patients. In this study, we tried to develop novel intranasal microemulsion for simultaneous delivery of carbamazepine and Vitamin B₆ for treatment of epilepsy. <strong>Materials and Methods: </strong>For simultaneous estimation of Carbamazepine and Vitamin B₆, second derivative spectroscopy method was developed and validated. The ME containing CBZ, in lipophilic phase and Vitamin B₆ in aqueous phase was studied for physicochemical characters and ex vivo diffusion through sheep nasal mucosa. The maximal electroshock (MES)- induced seizure models was used to establish the pharmacodynamic credentials of the microemulsion. <strong>Results: </strong>The wavelength selected for Carbamazepine and Vitamin B₆ were 231 nm and 250 nm respectively. It was found that prepared microemulsion is stable with globule size of 395+12 nm. Diffusion across sheep nasal mucosa followed zero order kinetics for carbamazepine and Vitamin B₆ in the prepared microemulsion. It was found that the hind limb extension time and the recovery time were significantly different from control group (<em>p</em>&lt;0.05). The microemulsion remained stable after dilution, centrifugation and freeze thaw cycle as tested for particle size, zeta potential and percentage transmission. <strong>Conclusion:</strong> The proposed microemulsion should form the basis for treatment of epilepsy which warrants co-administration of micronutrients. <strong>Key words:</strong> Carbamazepine, Intranasal Microemulsion, Pharmacodynamic, Simultaneous Delivery, Vitamin B₆.

Biochar Nanoparticles over TiO2 Nanotube Arrays: A Green Co-Catalyst to Boost the Photocatalytic Degradation of Organic Pollutants

Biochar nanoparticles (BC NPs), produced by low temperature pyrolysis (350 °C) of microalgae (Nannochloropsis sp.) and nutshells, are proposed as low-cost and sustainable co-catalysts to promote the photocatalytic activity of TiO2 nanotube (NT) arrays towards the degradation of methylene blue (MB) used as an organic pollutant model molecule. BC NPs (size &lt; 25 nm) were obtained by treating bulk BC (i.e., biomass after pyrolysis) by sonication–centrifugation cycles in a water solution. The filtered BC NPs dispersion was deposited by simple drop-casting on the TiO2 NT support. The BC loading was varied by performing multiple depositions. Photocatalytic experiments under UV light (365 nm) revealed that the decoration with BC NPs significantly improves the TiO2 photoactivity. Such enhancement is mainly influenced by the amount of BC deposited; upon optimizing the BC deposition conditions, the rate of photocatalytic degradation of MB increases approximately three times with respect to bare TiO2, almost irrespective of the nature of the raw material. The greater photocatalytic activity of BC-TiO2 can be attributed to the synergistic combination of reactant/product adsorption and catalytic degradation of the adsorbed organic pollutant, as well as an improved charge carrier separation and electron transfer.

Media and strain studies for the scaled production of cis-enone resorcylic acid lactones as feedstocks for semisynthesis

Resorcylic acid lactones (RALs) with a cis-enone moiety, represented by hypothemycin (1) and (5Z)-7-oxozeaenol (2), are fungal secondary metabolites with irreversible inhibitory activity against protein kinases, with particularly selective activity for inhibition of TAK1 (transforming growth factor beta-activated kinase 1). Gram-scale quantities of these compounds were needed as feedstock for semi-synthesizing RAL-analogues in a step-economical fashion. To do so, this study had three primary goals: identifying fungi that biosynthesized 1 and 2, enhancing their production by optimizing the fermentation conditions on the lab scale, and developing straight forward purification processes. After evaluating 536 fungal extracts via an in-house dereplication protocol, three strains were identified as producing cis-enone RALs (i.e., MSX78495, MSX63935, MSX45109). Screening these fungal strains on three grain-based media revealed enhanced production of 1 by strain MSX78495 on oatmeal medium, while rice medium increased the biosynthesis of 2 by strain MSX63935. Furthermore, the purification processes were improved, moving away from HPLC purification to utilizing two to four cycles of resuspension and centrifugation in small volumes of organic solvents, generating gram-scale quantities of these metabolites readily. In addition, studying the chemistry profiles of strains MSX78495 and MSX63935 resulted in the isolation of ten other RALs (3-12), two radicinin analogues (13-14), and six benzopyranones (15-20), with 19 and 20 being newly described chlorinated benzopyranones.

Self-Nanoemulsifying Drug Delivery System (SNEDDS) for Oral Delivery of Cod Liver Oil

Cod liver oil (CLO) has long been used as medicine or as a functional food. The CLO is a potential source of vitamin D, vitamin A, and omega fatty acids (eicosapentaenoic acid/EPA and docosahexaenoic acid/DHA). Self-nanoemulsifying drug delivery system (SNEDDS) can enhance dissolution, absorption, and bioavailability of hydrophilic and lipophilic substances for oral administration. The objective of this study was to develop a SNEDDS of CLO with good physical characteristics and stability. The optimization formula was carried out using various ratios of oil, surfactant, and cosurfactant. The physical properties of SNEDDS were determined by transmittance percentage, dispersibility, robustness, thermodynamics stability (heating-cooling cycle, centrifugation, and freeze-thaw cycle), and globule size distribution. The optimum formula of CLO-SNEDDS was obtained at a ratio of surfactant and cosurfactant 2 : 1 and a comparison of oil and surfactant mixtures 1 : 6. The CLO-SNEDDS meets the requirement of percent transmittance (97.90±0.85), dispersibility (grade A), and stability based on robustness and thermodynamic stability tests. Diluted SNEDDS has an average globule size of 125 nm with a polydispersity index (PDI) of 0.515. CLO-SNEDDS preparation has good physical characteristics and stability.

Preparation of Human Tissues Embedded in Optimal Cutting Temperature Compound for Mass Spectrometry Analysis.

Sphingolipids are cellular components that have well-established roles in human metabolism and disease. Mass spectrometry can be used to determine whether sphingolipids are altered in a disease and investigate whether sphingolipids can be targeted clinically. However, properly powered prospective studies that acquire tissues directly from the surgical suite can be time consuming, and technically, logistically, and administratively challenging. In contrast, retrospective studies can take advantage of cryopreserved human specimens already available, usually in large numbers, at tissue biorepositories. Other advantages of procuring tissues from biorepositories include access to information associated with the tissue specimens including histology, pathology, and in some instances clinicopathological variables, all of which can be used to examine correlations with lipidomics data. However, technical limitations related to the incompatibility of optimal cutting temperature compound (OCT) used in the cryopreservation and mass spectrometry is a technical barrier for the analysis of lipids. However, we have previously shown that OCT can be easily removed from human biorepository specimens through cycles of washes and centrifugation without altering their sphingolipid content. We have also previously established that sphingolipids in human tissues cryopreserved in OCT are stable for up to 16 years. In this report, we outline the steps and workflow to analyze sphingolipids in human tissue specimens that are embedded in OCT, including washing tissues, weighing tissues for data normalization, the extraction of lipids, preparation of samples for analysis by liquid chromatography electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS), mass spectrometry data integration, data normalization, and data analysis.

Antimicrobial Efficacy of a Novel Antibiotic-Eluting Injectable Platelet-Rich Fibrin Scaffold against a Dual-Species Biofilm in an Infected Immature Root Canal Model.

Background and Aims This study was aimed at evaluating the antibacterial property of an injectable platelet-rich fibrin (I-PRF) scaffold containing triple antibiotic mixture against an Actinomyces naeslundii (A. naeslundii) and Enterococcus faecalis (E. faecalis) biofilm in an infected immature root canal model. Methods A dual-species biofilm was inoculated inside the root canals via a series of centrifugal cycles. The samples were allocated to three experimental groups (i.e., G1: triple antibiotic mixture, G2: I-PRF containing triple antibiotic mixture, and G3: antibiotic-free I-PRF scaffold) and two control groups (G4: seven-day biofilm untreated and G5: bacteria-free untreated). Results Bacterial gene quantification change and the overall reduction of live bacteria were evaluated. The highest antibacterial activity against A. naeslundii belonged to G2. However, G1 and G2 had similar antibacterial property against E. faecalis (p value = 0.814). In general, experimental groups revealed higher levels of antibacterial activity against E. faecalis than against A. naeslundii (p value < 0.001). Notably, G2 could dramatically decrease the number of live bacteria up to near 92%. Conclusions The current study provides insight into the antibacterial property of an antibiotic-eluting I-PRF scaffold against a dual-species biofilm colonized inside the root canal. The fabricated scaffold contains not only the antibiotics but also the growth factors, which favor the regeneration.

Bioaccessibility of potentially toxic metals in soil, sediments and tailings from a north Africa phosphate-mining area: Insight into human health risk assessment

The risk assessment of phosphate mining/processing industrial activities on the environment and human health is crucial to properly manage and minimize the risks over time. In this work, we studied the inhalation and dermal bioaccessibility of potentially toxic metals (PTM) in different particle-size fractions of urban soil, sediments and tailings from Gafsa-Metlaoui phosphate mining area, to assess afterwards the non-carcinogenic (NCR) and carcinogenic (CR) risks for the health of local citizens and workers constantly exposed to airborne particulate matter (PM) originating from these sources of contamination. Samples were separated in particle-size fractions by centrifugation and consecutive cycles of sedimentation and decanting. The pseudo-total concentrations and bioaccessible fractions of PTM were extracted by aqua regia and in vitro bioaccessibility tests, respectively. Both sediments and tailings showed higher-than-background concentrations of PTM (mainly Cd, Zn and Cr), with a tendency to accumulate these metals in fine particles (<10 μm). In urban soil, only Cd was above the background concentration. The bioaccessibility of PTM via inhalation was significantly higher in artificial lysosomal fluid (ALF) than in simulated epithelial lung fluid (SELF): basically, Cd was the most bioaccessible metal (relative bioaccessibility up to 80%), followed by the medium-to-high bioaccessible Zn (47%), Pb (46%) and Cu (39%), and the least bioaccessible Cr (16%). In synthetic skin surface liquid (NIHS 96-10), only Cd was bioaccessible at worrying extent (20–44%). On the basis of US.EPA risk assessment, the exposure to PTM bioaccessible fractions or pseudo-total concentrations would not cause serious NCR and CR risks for human health. Significant health risks (Hazard Index >1 and CR > 10−4), especially for children, can occur if ingestion route is also considered. The findings underline the need for adequate protection of contaminated soil, sediments and mine tailings laying nearby urban agglomerates, to reduce the health risks for inhabitants and workers of Gafsa-Metlaoui mining area.

D-optimal design-assisted Elaeis guineensis leaves extract in olive oil-sunflower seed nanoemulsions: development, characterization, and physical stability

A three-factor D-optimal mixture design was used to prepare the Elaeis guineensis leaves extract (EgLE) in olive oil-sunflower seed nanoemulsions. The assessed independent variables were the components of an oil-based nanoemulsion that included oil (8–12%, w/w), Span 80:Brij L23 (28–30%, w/w) and aqueous (56–60% w/w) with mean droplet size (MDS) and polydispersity index (PDI) as the responses. Analysis of variance revealed that both responses fitted a quadratic polynomial model and a residual standard error of <5% indicated good agreement between the experimental and predicted values. Optimal formulation with the lowest MDS and PDI was established to be 10% (w/w) oil, 29% (w/w) Span 80:Brij L23 and aqueous at 58% (w/w). Atomic force micrographs showed the MDS of an optimized EgLE w/o nanoemulsion being <200 nm and was kinetically stable (zeta potential: −30.0 ± 0.7 mV). The system showed satisfactory conductivity (0.70 ± 0.02 µS cm−1) and pH (5.6 ± 0.3), alongside resistance to phase separation under centrifugation and freeze-thaw cycles. The nanoemulsion also exhibited shear thinning and pseudoplastic properties, implying good stability against destabilization by coalescence. It can be construed that the developed EgLE nanoemulsion showed potential as a natural-based personal care product. This is the first report on the preparation of EgLE as bioactive ingredients in a w/o nanoemulsion for topical application.