Powder Suspension Research Articles

Preclinical development and characterisation of PP353, a formulation of linezolid for intradiscal administration.

Bacterial infection of the intervertebral disc can lead to vertebral endplate edema known as Modic changes, with associated chronic low back pain. Oral antimicrobial therapy has shown efficacy but relies on prolonged dosing and may not be optimal in terms of patient outcome, side effects, or antibiotic stewardship. There is no antibiotic formulation approved for intradiscal administration. Here, we describe the development and preclinical characterization of a formulation of linezolid, a suspension of 50 mg/mL micronized powder, for intradiscal administration. Micronization, particle size analysis, Franz cell diffusion assays, ex vivo bioassay, and estimates of gelling temperature were used to optimize the composition and properties of the formulation. Performance of the formulation was assessed using sheep to characterize the pharmacokinetics and a model of intradiscal infection was developed to demonstrate efficacy. Suitability for human administration was demonstrated in a Good Laboratory Practice (GLP) local tolerance study. Micronized linezolid, formulated as a powder suspension using a vehicle containing poloxamer 407 and iohexol, provided a temperature-dependent radio-opaque gel that was suitable for image-guided percutaneous intradiscal administration. Efficacy in a sheep model of intradiscal Staphylococcus aureus infection was demonstrated. The formulation provides a high level of sheep disc tissue exposure, with Cmax of 6500 μg/g and limited systemic exposure, with a plasma Cmax of 0.04 μg/mL per 0.1 mL dose (5 mg of linezolid). Deconvolution of plasma linezolid pharmacokinetics correlated with linezolid remaining in the disc over time. Observations from a GLP local tolerance study with the linezolid formulation were of a minor nature and related to the intradiscal administration procedure. Linezolid can be formulated for image-guided percutaneous intradiscal administration. The formulation is now in a Phase 1b clinical trial to evaluate safety, pharmacokinetics, and efficacy in patients with CLBP and suspected bacterial infection.

Long-term leaching kinetics and solution chemistry of aqueous BaTiO3 powder suspensions: a numerical model supported experiment.

The advent of lead-free perovskite materials with favorable toxicity profiles has made them candidates for in vivo and environmental applications. However, their tendency to leach A-site cations raises concerns about toxicity, catalytic efficiency, and slurry properties. The present study investigates the long-term leaching kinetics of BaTiO3 powders over 31 days in aqueous solutions of varying pH levels. Using ICP-MS analysis and a numerical model based on the Unreacted Shrinking Core (USC) principle. The study extends the understanding of BaTiO3 stability beyond previously reported timeframes. The findings highlight the material's long-term stability, with implications for biomedical and environmental applications.

Pharmacokinetics and Bioequivalence of Two Powders of Azithromycin for Suspension: A Nonblinded, Single-Dose, Randomized, Three-Way Crossover Study in Fed and Fasting States Among Healthy Chinese Volunteers.

Azithromycin, a macrolide antibiotic, is commonly used to treat mild-to-moderate bacterial infections. This research aimed to evaluate the pharmacokinetics (PK) properties and bioequivalence (BE) of two azithromycin (EQ 100 mg base/packet) powders for suspension in Chinese healthy participants in fed and fasting conditions. A total of 90 Chinese healthy participants were enrolled in this nonblinded, single-dose, randomized, semireplicate, three-period, three-sequence, crossover study. Of them, 42 and 40 were categorized to the fed and fasting conditions, respectively. The washout period between doses was 21 days. Blood specimens were harvested prior to administering the drug and 194 h following administration. The plasma levels of azithromycin were analyzed using a validated liquid chromatography-tandem mass spectrometry (LC-MS/MS) approach. PK parameters were measured using noncompartmental analysis. This research compared BE between the reference and test products using the average bioequivalence (ABE) or reference-scaled average bioequivalence (RSABE) method, considering the within-subject variability (SWR) of the reference preparation. Adverse events (AEs) were monitored to examine safety and tolerability. The RSABE method (SWR ≥ 0.294) was used to determine the BE of maximal plasma concentration (Cmax) in both fed and fasting conditions. In the ABE approach, (SWR < 0.294) was adopted to assess the BE of the area under the plasma concentration-time curve from time zero to the last measurable time point (AUC0-t) and determine the area under the plasma concentration time curve from time zero to time infinity (AUC0-inf). In the fasting condition, the point estimate of the test/reference ratio for Cmax was 1.08, with a 95% upper confidence bound of - 0.05 < 0.00. The geometric mean ratio (GMRs) for AUC0-t and AUC0-inf was 115.21% [90% confidence interval (CI) 107.25-123.27%] and 113.07% (90% CI 105.14-121.61%), respectively. In the fed condition, the point estimate of the test/reference ratio for Cmax was 0.94, with a 95% upper confidence bound of - 0.10 < 0.00. The GMR for AUC0-t and AUC0-inf was 99.51% (90% CI of 91.03-108.78%) and 99.43% (90% CI 91.73-107.78%), respectively. These data all satisfied the BE criteria for drugs with high variability. All AEs were transient and mild, and no severe AEs were observed. Our study indicated that the test and reference products of azithromycin (EQ 100 mg base/packet) powder for suspension were bioequivalent and safe in healthy Chinese participants, irrespective of the feeding condition. CLINICAL TRIAL REGISTRATION (CHINADRUGTRIALS.ORG.CN): CTR20232646, registered on 25 August 2023.

A comparative characterization analysis of electrode materials for optimal deposition on copper by advancing electrical discharge coating

This research explores the efficiency of Electrical Discharge Coating (EDC) as an advanced surface modification technique using powder suspension, conventional electrodes, and 3D printed electrodes (3DPE), focusing on Ti6Al4V alloys. Conventional Ti electrodes resulted in 100% titanium content with a thickness of 110 µm, while the powder suspension coating was inadequate. The use of 3D printed electrodes showed promising results, with uniform deposition of 61.20 µm thickness and enhanced surface properties under 10 A current. Further analysis of 3D printed Ti6Al4V EDC revealed a higher Ti percentage of 44.20%, TiC formation of 84.17%, and enhanced microhardness with lower surface roughness. Thorough optimization of 3D printed electrode EDC has been undertaken. The study suggests the potential replacement of traditional electrodes such as powder metallurgy with 3D printed counterparts, advancing surface modification techniques and opening new avenues for materials engineering and manufacturing processes.

Fabrication of customized open-cell titanium foams by direct foaming for biomedical applications

Titanium (Ti) foams offer a promising alternative for bone reconstruction and repair due to their high porosity and lower stiffness compared to solid metals, which improves in vivo osseointegration by reducing the stress shielding effect and allowing bone ingrowth. In this work, customized Ti foams were successfully fabricated for the first time at room temperature using a direct foaming method. Ti powder suspension with a water-soluble surfactant and environmentally friendly thickener was foamed by mechanical stirring. Then, 3D-printed moulds were utilized to achieve near-net shape foams, which were subsequently consolidated by sintering, thus avoiding the need for complex processing of molten Ti. The resulting Ti foams exhibited a cancellous-like open-cell structure, high porosity (> 80%), and a five times higher effective surface area than a 3D Ti mesh with a primitive cubic-based cell fabricated by additive manufacturing. In addition, the Ti foams exhibited similar mechanical properties to cancellous bone and facilitated the adhesion, proliferation, and maturation of human osteoblasts in vitro.

Enhancing Mild Steel Surface Characteristics through Electrical Discharge Coating with Titanium Dioxide Suspension

In this research, surface modification of mild steel was carried out by using electric discharge coating (EDC) with titanium dioxide (TiO2) powder suspension. The concentrations of TiO2 powder were varied and their effect on the surface roughness and deposited element were investigated. The results showed that elements such as titanium, carbon, copper, oxygen, zinc and iron were successfully coated on the mild steel surface. Aside from that, the weight % of the titanium element increased with an increase of TiO2 powder concentration. The surface roughness was also reduced 62.9% by using 5 g/l TiO2 powder when compared to the pure kerosene oil.

Effects of mulberry leaf enrichment with Lepidium sativum L. seed powder suspension on the economic parameters of Bombyx mori L

The phytochemicals of high nutritional and functional properties in Lepidium sativum L. (garden cress) seeds have nominated their seed powder (regardless of the concentration used) for enrichment of mulberry leaves in order to enhance Bombyx mori L. larval feeding, and consequently to gain ground in sericulture industry. As expected, B. mori larval feeding on L. sativum-enriched mulberry leaves showed not only a remarkable increase in mean values of certain economic parameters of B. mori, such as cocoon weight, cocoon shell weight, pupal weight, and egg yield, compared with the control group, but also showed a phenomenal increase in egg counts (on average, ca. 958–1256 eggs laid per female moth) and a significant increase in egg size (measured as egg surface area and egg volume). Male or female moth larval diet has significantly influenced the reproductive performance or fitness of both sexes of B. mori in terms of large-sized moths (measured as forewing, hind femur, and hind tibia lengths) and highly fecund moths (i.e., increased fecundity and spermatophore counts per female moth, and large-sized eggs). On the basis of B. mori female moth reproductive index, the female moths from L. sativum-fed larvae proved to have a lower reproductive index compared to their corresponding value for females of the control group, indicating more efficient utilization of larval resources for B. mori reproduction. Quantification of the three main physiological resources viz., protein, lipid and carbohydrate in the internal reproductive tract of B. mori female moths at death has nominated the female moth abdomens, or simply their bodies, as being a reasonable natural source of protein, lipid, and carbohydrate, to be involved in certain manufactures (e.g., pet feed formulations) instead of discarding them as a source of environmental pollution. Evidently, the L. sativum seed powder is of considerable interest because it remarkably improves the performance of such an economically important insect, B. mori. This is the first study for evaluating the efficacy of L. sativum seed powder in sericulture field to enhance B. mori productivity parameters.

(Invited) Photocatalyst Sheets for Scalable Solar Fuels Production from Water and CO2

The development of sunlight-driven water splitting or CO2 reduction systems with high efficiency, scalability, and cost-competitiveness is a central issue for mass production of fuels and energy-rich chemicals.1 Z-scheme photocatalytic systems, employing the two-step photoexcitation of photocatalyst I (PC I) and photocatalyst II (PC II), have garnered significant attention. These systems can utilize narrow bandgap semiconductors capable of either water/CO2 reduction or oxidation potential, enabling the conversion of solar energy. The challenge in developing a Z-scheme system lies in ensuring efficient electron transfer between PC I and PC II.2 To address these challenges, we have developed all-solid-state devices—photocatalyst sheets—for photocatalytic water splitting.3,4 These sheets establish a direct connection between PC I and PC II particles via a conductive layer or conductive nanoparticles, effectively facilitating electron transfer between them. Consequently, these photocatalyst sheets achieve a high solar-to-H2 conversion efficiency exceeding 1%. They outperform analogous powder suspension and photoelectrochemical systems in their optimal reaction solutions due to the effective electron transfer enabled by the conductive layer or nanoparticles bridging PC I and PC II. Compared to traditional photoelectrochemical systems, the photocatalyst sheet design significantly reduces the effects of H+/OH− concentration overpotentials and the IR drop due to the proximity of PC I and PC II in the sheet. Hence, the design of these photocatalyst sheets proves highly suitable for efficient large-scale applications.Additionally, efforts to demonstrate fuel production from CO2 powered by sunlight are currently hampered by the requirements of sacrificial electron donors or external bias, and lack of efficiency, selectivity and scalability. To overcome those barriers, we integrate a selective molecular catalyst on semiconductor light absorbers to form a wireless and monolithic photocatalyst sheet.5 For instance, by incorporating a phosphonated cobalt(II) bis(terpyridine) catalyst (CotpyP) onto a modified SrTiO3:La,Rh|Au|BiVO4:Mo sheet, we have achieved a solar-to-formate conversion efficiency of 0.08%. This configuration harnesses the high selectivity of molecular catalysts for CO2 reduction and the strong water oxidation power of semiconductors, yielding a formate selectivity of 97±3% through the coupled process of CO2 reduction and water oxidation. We have also developed a bio-abiotic hybrid system by combining a photocatalyst sheet, capable of scalable photocatalytic water splitting, with nonphotosynthetic bacteria acting as biocatalysts.6 When pairing CO2-fixing acetogenic bacteria, Sporomusa ovata, with a SrTiO3:La,Rh|ITO|BiVO4:Mo sheet, a solar-to-acetate conversion efficiency of ~0.7% was achieved (as shown in the figure). This coupling exhibited an impressive selectivity for acetate production in CO2 reduction reactions, reaching ~100%.Our study offers novel and versatile strategies toward sustainable solar fuel production.References Q. Wang, C. Pornrungroj, S. Linley, E. Reisner. Nat. Energy 7 , 13–24 (2022)Y. Sasaki, H. Nemoto, K. Saito, A. Kudo. J. Phys. Chem. C 113, 17536–17542 (2009)Q. Wang, T. Hisatomi, Q. Jia, H. Tokudome, M. Zhong, C. Wang, Z. Pan, T. Takata, M. Nakabayashi, N. Shibata, Y. Li, I. D. Sharp, A. Kudo, T. Yamada, K. Domen. Nat. Mater. 15,611–615 (2016)Q. Wang, T. Hisatomi, Y. Suzuki, Z. Pan, J. Seo, M. Katayama, T. Minegishi, H. Nishiyama, T. Takata, K. Seki, A. Kudo, T. Yamada, K. Domen. J. Am. Chem. Soc. 139, 1675–1683 (2017)Q. Wang, J. Warnan, S. Rodríguez-Jiménez, J. J. Leung, S. Kalathil, V. Andrei, K. Domen, E, Reisner. Nat. Energy 5, 703–710 (2020)Q. Wang, S. Kalathil, C. Pornrungroj, D. C. Sahm, E. Reisner. Nat. Catal. 5, 633–641 (2022) Figure 1

Bioavailability of Bilastine Oral Self-nanoemulsion: Comparative Study with Commercial Formula in Rats

Background: Bilastine (BL) is a novel non-sedating second-generation antihistamine, and its bioavailability is about 60%. Objective: To compare the bioavailability of prepared oral self-nanoemulsions of BL (BL-SNE) with that of pure BL and marketed tablets. Methods: Four groups of Wistar rats were used in this study, each with six rats weighing between 200 and 250 g. They were treated orally using a a gavage tube. The groups were fed either with conventional tablets ("Alerbix®") after being ground and dispersed with deionized water (DIW), treated with BL-SNE or fed with pure BL powder suspension. The fourth group did not receive any medication. The concentration of BL in the rat’s plasma was measured using HPLC. We used Trandolapril as an an internal standard. Results: The bioavailability results for the the prepared formula, tablet, and pure BL were 24289.91 ng/ml, 0.75 h, 12.81, 97844.7 ng.h/ml, and 98732.9 ng/ml, respectively, for the BL-SNE formula, and 15840.37, 1.0, 13.014, 66140.4, and 67088.3 for the tablets. Meanwhile, the BL suspension demonstrates 10830.12, 1.0 h, 12.96, 59397.12 ng/ml, and 60534.64 ng/ml, respectively. Conclusions: The relative bioavailability of BL-SNE was 1.47 and 1.6 times higher than that of marketed tablets and pure BL, respectively. This indicates an improvement in BL's bioavailability.

Unravelling the emulsifying properties of unfractionated plant powders: From interface to bulk

Crude plant-based by-product powders can stabilise emulsions. Their chemical composition varies substantially depending on both the source plant and the manufacturing process, resulting in different emulsifying properties. This diversity was assessed by studying the emulsifying properties of three chemically different by-products (apple seed cake: protein-rich, apple pomace: non-protein soluble-rich, and liquorice root: mostly water-insoluble) ground into fine and coarse powders. The properties (droplet size, particle anchoring ratio, rheological properties) of the powder-stabilised emulsions were monitored for one month and linked to powder suspensions properties assessed in the presence and absence of solid particles. The interfacial scale was emphasized as the primary location to study the interactions between mixed emulsifiers. The interfacial properties of the powders, and especially the competition between solid particles and soluble compounds, were successfully linked to emulsions properties. Protein-rich powder-stabilised emulsions contained smaller droplets, whose diameter varied slightly with particle size, confirming soluble macromolecules dominance at interfaces. With the soluble powder, particles and soluble macromolecules acted synergistically at both interfacial and bulk scales, indicating mixed interfaces. Particle size determined the properties of the emulsions stabilised with insoluble powder, suggesting interfaces mostly composed of solid particles. Solid particles ensured the gravitational and thermodynamic stability of all powder-stabilised emulsions.

Potential of artificial soil preparation for vegetation restoration using red mud and phosphogypsum

Red mud and phosphogypsum have long been a focus and challenge in global industrial waste management, and their low-cost and large-scale utilization technology has always been an urgent need. This study is based on the strong acid-base neutralization reaction between red mud and phosphogypsum, which contain an elemental composition similar to that of natural soil, red mud itself has characteristic of clay minerals, and other auxiliary materials (i.e. rice husk powder, bentonite, fly ash, polyacrylamide flocculant and microbial suspension) were added, so as to explore the potential of synergistically prepared artificial soil for vegetation restoration. The results showed that the artificial soils exhibited physicochemical characteristics (e.g., pH, moisture content, cation exchange capacity) similar to those of natural soil, along with abundant organic matter, nitrogen, phosphorus, and potassium contents, meeting the growth requirements of plants. The artificial soils were able to support favorable growth of suitable plants (e.g., sunflower, wheat, rye grass), accumulating high levels of diverse enzymatic activities, comparable to those in natural soils (e.g., catalase, urease, phosphatase), or even surpassing natural soils (e.g., sucrase), and rich microorganism communities, such as Cyanobacteria, Proteobacteria, Actinobacteria in the bacteria domain, and Ascomycota in the fungi domain, were initially developed. It's suggested that preparing 1 ton of artificial soil entails synergistic consumption of 613.7 kg of red mud and 244.6 kg of phosphogypsum, accounting for mass proportions of 61.4 % and 24.5 %, respectively. In future, more evaluations on the leaching loss of nutrients and alkalinity and the environmental risks of heavy metals should be conducted to more references for the artificial soil application. In summary, the preparation of artificial soil is a very simple, efficient, scalable and low-cost collaborative resource utilization scheme of red mud and phosphogypsum, which has great potential for vegetation restoration in some places such as tailings field and soil-deficient depression.

Production and characterisation of microfluidized olive powder

SummaryMicrofluidization has been gaining popularity as a size reduction process in recent years. In this study, microfluidization technique was used for olives to change the cell wall structure and decrease the size of oil droplets. Olive powders were produced from green, black and raw olives using freeze drying following microfluidization at 1200 bar. Antioxidant activity was not affected significantly for all powders while total phenolic content decreased for green and raw olive powders with microfluidization. Among all olive powders, the one raw olive gave the highest antioxidant activity and phenolic content. In microscopic analysis, Scanning Electron Microscope images revealed that microfluidization results in finer particles which are self‐encapsulated by trapping the oil droplets. Stability analysis through Turbi Scan and rheological measurements of the powder suspensions showed that microfluidization process enables more stable suspensions having higher water holding capacity. Herschel–Bulkley model was found for the flow behaviours of the olive powder suspensions.

In vivo antimalarial efficacy of Artemisia afra powder suspensions

BackgroundA global death toll of 608,000 in 2022 and emerging parasite resistance to artemisinin, the mainstay of antimalarial chemotherapy derived from the Chinese herb Artemisia annua, urge the development of novel antimalarials. A clinical trial has found high antimalarial potency for aqueous extracts of A. annua as well as its African counterpart Artemisia afra, which contains only trace amounts of artemisinin. The artemisinin-independent antimalarial activity of A. afra points to the existence of other antimalarials present in the plant. However, the publication was retracted due to ethical and methodological concerns in the trial, so the only evidence for antimalarial activity of A. afra is built on in vitro studies reporting efficacy only in the microgram per milliliter range. HypothesisOur study aims to shed more light on the controversy around the antimalarial activity of A. afra by assessing its efficacy in mice. In particular, we are testing the hypothesis that A. afra contains a pro-drug that is inactive in vitro but active in vivo after metabolization by the mammalian host. MethodsPlasmodium berghei-infected mice were treated once or thrice (on three consecutive days) with various doses of A. afra, A. annua, or pure artemisinin. ResultsAqueous powder suspensions of A. annua but not A. afra showed antimalarial activity in mice. ConclusionOur experiments conducted in mice do not support the pro-drug hypothesis.

The study of marketing opportunities for the use of the raw material of feverfew (Tanacetum parthenium L.) in the pharmacotherapy of musculoskeletal system diseases

Aim. To form a modern idea of the market structure and trends in the consumption of drugs for the pharmacotherapy of rheumatoid arthritis, to determine the possible potential for use of plant raw material of feverfew (Tanacetum parthenium). Materials and methods. The study was conducted using the structural analysis, logical and graphical methods, and marketing analysis methods. Results. It was found that in the pre-war period the market for drugs affecting the musculoskeletal system developed quite vigorously – its growth rate in the period of 2020-2021 ranged from 16 to 29 % in natural units and from 20 to 30 % in monetary terms. According to the structure of producing countries, the market was significantly import-dependent. The market for synthetic drugs was quite saturated, represented by various dosage forms – tablets, powder for suspension, injection solutions (ampoules), granules, capsules, sachets, alcohol solutions, oil solutions, suppositories, oral suspensions, transdermal patches, gels, ointments. The research was conducted taking into account the study of marketing opportunities for the use of the raw material of Tanacetum parthenium in the pharmacotherapy of diseases of the musculoskeletal system since this raw material had certain advantages compared to synthetic analogs. It should be noted that the market of herbal medicines for the treatment of the musculoskeletal system diseases or the prevention of their manifestations is very limited and is represented by a minimum number of product items and one representative of the medicinal flora – Symphytum officinale. In addition, 90 % of the market for this group of drugs belongs to foreign manufacturers. Although research of the market for biological supplements indicates a certain demand for products based on the medicinal plant raw material. Conclusions. Based on the trends identified, we can state the positive development of the market for drugs that affect the musculoskeletal system, the prospects for the development of drugs based on the medicinal plant raw material, including Tanacetum parthenium.

Wet SPF: A wet powder suspension for the detection of latent fingermarks on the sticky side of adhesive tape for use in Seychelles

WET UCIO is an inexpensive carbon-based powder suspension, reportedly as effective as commercially available formulations for latent fingermark detection on the sticky side of adhesive tapes. However, the surfactant solution used in WET UCIO is not readily accessible outside Europe, limiting its use in Seychelles or other non-European jurisdictions. In this study, the UCIO formulation was modified based on a ‘frugal forensic’ approach, by replacing the surfactant solution with an in-house sodium dodecyl sulfate solution prepared in 5 % aqueous ethanol. A comparative assessment against Wetwop™ using eight different pressure-sensitive adhesive tapes found that the modified formulation was at least as effective as commercial powder suspension. Modifying this technique under the frugal forensic framework has enhanced its accessibility to other jurisdictions and is recommended for validation in Seychelles.

Modified powder suspensions for fingermark detection on adhesive tapes in austere or contested environments

ABSTRACT Pressure-sensitive adhesive tapes may be associated with a wide range of criminal and terrorist activity as physical evidence. In this study, a carbon powder suspension formulation for the detection of latent fingermarks on the adhesive side of tapes was modified by using consumer products as alternative surfactant sources. The modified formulations were used to successfully develop latent fingermarks deposited on transparent adhesive tape. This project ultimately intends to establish the performance windows of the modified techniques to allow evidence-based decision-making during technical exploitation in contested and austere environments.

Development of a dry powder insufflation device with application in in vitro cell-based assays in the context of respiratory delivery

Research on pharmaceutical dry powders has been increasing worldwide, along with increased therapeutic strategies for an application through the pulmonary or the nasal routes. In vitro methodologies and tests that mimic the respiratory environment and the process of inhalation itself are, thus, essential. The literature frequently reports cell-based in vitro assays that involve testing the dry powders in suspension. This experimental setting is not adequate, as both the lung and the nasal cavity are devoid of abundant liquid. However, devices that permit powder insufflation over cells in culture are either scarce or technically complex and expensive, which is not feasible in early stages of research. In this context, this work proposes the development of a device that allows the delivery of dry powders onto cell surfaces, thus simulating inhalation more appropriately. Subsequently, a quartz crystal microbalance (QCM) was used to establish a technique enabling the determination of dry powder deposition profiles. Additionally, the determination of the viability of respiratory cells (A549) after the insufflation of a dry powder using the developed device was performed. In all, a prototype for dry powder insufflation was designed and developed, using 3D printing methods for its production. It allowed the homogenous dispersion of the insufflated powders over a petri dish and a QCM crystal, and a more detailed study on how dry powders disperse over the supports. The device, already protected by a patent, still requires further improvement, especially regarding the method for powder weighing and the efficiency of the insufflation process, which is being addressed. The impact of insufflation of air and of locust bean gum (LBG)-based microparticles revealed absence of cytotoxic effect, as cell viability roughly above 70 % was always determined.

Posaconazole in paediatric malignancy and haematopoietic stem cell transplant: dosing to achieve therapeutic concentration.

Posaconazole is increasingly used for the treatment and prophylaxis of invasive fungal infections in immunocompromised children. We aimed to review evidence for paediatric posaconazole dosing regimens focusing on attainment of target concentrations and frequency of adverse effects. In May 2023, the Cochrane, Embase, MEDLINE and PubMed databases were searched for articles reporting posaconazole dosing in children with malignancy or post-haematopoietic stem cell transplantation. Studies reporting the attainment of target serum concentrations were included. Overall, 24 studies were included. Eighteen studies of the oral suspension consistently reported poor attainment of target concentrations for prophylaxis (≥0.7 µg/mL, 12%-78%) despite high daily doses of 14-23 mg/kg/day (max. 1200 mg/day). Target attainment was significantly affected by gastric pH and food intake. Six studies of the delayed-release tablet (DRT) reported 58%-94% achieved concentrations ≥0.7 µg/mL, with the majority using lower doses of 4-12 mg/kg/day (max. 300 mg/day). Similarly, one study of powder for oral suspension found 67%-100% achieved target concentrations with a dose of 6 mg/kg/day (max. 300 mg/day). As expected, the IV formulation had high attainment of prophylaxis targets (81%-90%) with 6-10 mg/kg/day (max. 400 mg/day). All formulations were well tolerated, and no relationship between adverse effects and posaconazole concentrations was identified. The required posaconazole dose in immunocompromised children varies depending on the formulation. The IV infusion had the highest attainment of therapeutic concentration followed by the DRT and powder for suspension. By contrast, the oral suspension had low attainment of target concentrations despite higher daily doses.

Photocatalytic Conversion of Methane to Ethanol at a Three-Phase Interface with Concentration-Matched Hydroxyl and Methyl Radicals.

The direct oxidation of CH4 to C2H5OH is attractive but challenging owing to the intricate processes involving carbon-chain growth and hydroxylation simultaneously. The inherent difficulty arises from the strong tendency of CH4 to overoxidize in the commonly used pressurized powder suspension systems rich in reactive oxygen radicals (ROR), which are specifically designed for CH4 concentration and activation. Meanwhile, the strong tendency of nucleophilic attack of potent ROR on the C-C bond of the resulting product C2H5OH ultimately leads to a higher selectivity for C1 oxygenates. This study addresses this multifaceted issue by designing a three-phase interface based on a hydrophilic floating Fe(III)-cross-linked macroporous alginate hydrogel film encapsulated with C3N4 [Fe(III)@ACN] to simultaneously enhance the accessibility of H2O and CH4 molecules to the active sites and species within the macroporous channel. The hydrophilic properties of Fe(III)@ACN allow the in situ production of H2O2 from C3N4 through the water oxidation reaction under irradiation. The concurrent photoinduced Fe(II) triggers Fenton reaction with H2O2 to produce •OH. The enhanced mass transfer of CH4 at the three-phase interface ensures the efficient formation of •CH3 by reacting with •OH, ultimately facilitating carbon-chain growth in the conversion pathway from CH4 to CH3OH and finally to C2H5OH with •CH3 and •OH present in comparable concentrations. Thus, the Fe(III)@ACN catalyst exhibits a remarkable 96% selectivity for alcohol, achieving a 90% selectivity for C2H5OH in the alcohol products. The C2H5OH production rate reaches 171.7 μmol g-1 h-1 without the need for precious-metal additive.

Numerical modeling of the process of extrusion of high-viscosity pastes

This paper provides a theoretical consideration of the process of paste extrusion using a piston dispenser. The paste is considered as a highly viscous suspension of terpineol and silver particle powder. As a result of numerical modeling, the distribution of silver particles in a steady paste flow was obtained. The excess pressure in the piston depending on its speed and the effective width of the track depending on the piston speed were obtained. Modeling showed that the viscosity of the paste has the greatest influence on the extrusion process. Application of the obtained dependencies will allow you to control the paste extrusion process.