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Molecular Pharmaceutics Nov 2023Dry powder inhaler (DPI) products are commonly formulated as a mixture of micronized drug particles and large carrier particles, with or without additional fine particle... (Review)
Review
Dry powder inhaler (DPI) products are commonly formulated as a mixture of micronized drug particles and large carrier particles, with or without additional fine particle excipients, followed by final powder filling into dose containment systems such as capsules, blisters, or reservoirs. DPI product manufacturing consists of a series of unit operations, including particle size reduction, blending, and filling. This review provides an overview of the relevant critical process parameters used for jet milling, high-shear blending, and dosator/drum capsule filling operations across commonly utilized instruments. Further, this review describes the recent achievements regarding the application of empirical and mechanistic models, especially discrete element method (DEM) simulation, in DPI process development. Although to date only limited modeling/simulation work has been accomplished, in the authors' perspective, process design and development are destined to be more modeling/simulation driven with the emphasis on evaluating the impact of material attributes/process parameters on process performance. The advancement of computational power is expected to enable modeling/simulation approaches to tackle more complex problems with better accuracy when dealing with real-world DPI process operations.
Topics: Powders; Drug Compounding; Administration, Inhalation; Drug Carriers; Computer Simulation; Dry Powder Inhalers; Particle Size; Aerosols
PubMed: 37783568
DOI: 10.1021/acs.molpharmaceut.3c00557 -
Handbook of Experimental Pharmacology 2024The formulation of drugs in poly(lactic-co-glycolic acid) (PLGA) nanoparticles can be accomplished by various methods, with nanoprecipitation and nanoemulsion being...
The formulation of drugs in poly(lactic-co-glycolic acid) (PLGA) nanoparticles can be accomplished by various methods, with nanoprecipitation and nanoemulsion being among the most commonly used manufacturing techniques to provide access to high-quality nanomaterials with reproducible quality. Current trends turned to sustainability and green concepts leading to a re-thinking of these techniques, particularly as the conventional solvents for the dissolution of the polymer suffer from limitations like hazards for human health and natural environment. This chapter gives an overview about the different excipients used in classical nanoformulations with a special focus on the currently applied organic solvents. As alternatives, the status quo of green, sustainable, and alternative solvents regarding their application, advantages, and limitations will be highlighted as well as the role of physicochemical solvent characteristics like water miscibility, viscosity, and vapor pressure for the selection of the formulation process, and for particle characteristics. New alternative solvents will be introduced for PLGA nanoparticle formation and compared regarding particle characteristics and biological effects as well as for in situ particle formation in a matrix consisting of nanocellulose. Conclusively, new alternative solvents are available that present a significant advancement toward the replacement of organic solvents in PLGA nanoparticle formulations.
Topics: Humans; Polylactic Acid-Polyglycolic Acid Copolymer; Polyglycolic Acid; Lactic Acid; Nanoparticles; Solvents; Particle Size
PubMed: 37306814
DOI: 10.1007/164_2023_659 -
Journal of Esthetic and Restorative... Dec 2023This study aimed to isolate the relationship between filler size and the surface properties of roughness and gloss before and after toothbrush abrasion for experimental...
OBJECTIVE
This study aimed to isolate the relationship between filler size and the surface properties of roughness and gloss before and after toothbrush abrasion for experimental resin-based composites (RBCs) containing uniform spherical fillers.
MATERIALS AND METHODS
Five experimental light-cured RBCs with different spherical filler sizes and three commercial RBCs were studied. Forty specimens were polished using silicon carbide papers. Gloss was measured after 0, 90, 180, and 360 min of simulated toothbrushing, and surface roughness was measured before and after 360 min of toothbrushing. Two-way ANOVA/Tukey's multiple comparison tests were used to compare the RBCs, and the correlation between particle size and surface roughness or gloss was also determined.
RESULTS
After polishing and toothbrushing, RBCs with smaller fillers exhibited significantly higher gloss and lower surface roughness, and RBCs with larger fillers exhibited lower gloss and higher surface roughness. A significant correlation was found between filler particle size and gloss and surface roughness both before and after toothbrush abrasion.
CONCLUSIONS
Gloss of RBCs containing fillers with larger particle sizes was significantly reduced. After toothbrushing abrasion, the surface roughness increased for all RBCs, except those containing the finest-sized fillers. The particle size of the filler is a critical determinant of the surface roughness and gloss of RBCs, after polishing and after toothbrushing.
CLINICAL SIGNIFICANCE
Increased surface roughness caused by toothbrush abrasion reduces the gloss of resin-based composites. Resin-based composites containing finer fillers best maintain glossiness after routine tooth brushing.
Topics: Particle Size; Materials Testing; Composite Resins; Dental Materials; Toothbrushing; Surface Properties; Dental Polishing
PubMed: 37449726
DOI: 10.1111/jerd.13105 -
European Journal of Pharmaceutical... Dec 2023This work presents a system, where deep learning was used on images captured with a digital camera to simultaneously determine the API concentration and the particle...
This work presents a system, where deep learning was used on images captured with a digital camera to simultaneously determine the API concentration and the particle size distribution (PSD) of two components of a powder blend. The blend consisted of acetylsalicylic acid (ASA) and calcium hydrogen phosphate (CHP), and the predicted API concentration was found corresponding with the HPLC measurements. The PSDs determined with the method corresponded with those measured with laser diffraction particle size analysis. This novel method provides fast and simple measurements and could be suitable for detecting segregation in the powder. By examining the powders discharged from a batch blender, the API concentrations at the top and bottom of the container could be measured, yielding information about the adequacy of the blending and improving the quality control of the manufacturing process.
Topics: Powders; Particle Size; Deep Learning; Chromatography, High Pressure Liquid; Technology, Pharmaceutical
PubMed: 37844806
DOI: 10.1016/j.ejps.2023.106611 -
Food Research International (Ottawa,... Aug 2023High-resolution (HR) visual imaging and spectral imaging are common computer vision-based techniques used for food quality analysis and/or authentication based on the...
High-resolution (HR) visual imaging and spectral imaging are common computer vision-based techniques used for food quality analysis and/or authentication based on the interaction of light and material surface and/or composition. The particle size of ground spices is an important morphological feature that affects the physico-chemical properties of food products containing such particles. This study aimed to interpret the impact of particle size of ground spice on its HR visual profile and spectral imaging profile using ginger powder as a representative spice powder model. The results revealed an increase in the light reflection with the decrease of particle size of ginger powder, which was manifested by the lighter colour (higher percentage of the colour code with lighter yellow colour) of the HR visual image and stronger reflection with spectral imaging. The study also revealed that, in spectral imaging, the influence of the particle size of ginger powder increased with rising wavelengths. Finally, the results indicated a relationship between spectral wavelengths, ginger particle size, and other natural variables of the products which might be generated from cultivation to processing. Ultimately, the impact of natural variables arising during the food production process on the physico-chemical properties of the product should be fully considered or even additionally evaluated prior to the application of specific food quality and/or authentication analytical techniques.
Topics: Zingiber officinale; Particle Size; Powders; Spices
PubMed: 37316086
DOI: 10.1016/j.foodres.2023.113023 -
Wiley Interdisciplinary Reviews.... 2023Nanoemulsions (NEs) are emulsions with particle size of less than around 100 nm. Reviewing the literature, several reports are available on NEs, including preparation,... (Review)
Review
Nanoemulsions (NEs) are emulsions with particle size of less than around 100 nm. Reviewing the literature, several reports are available on NEs, including preparation, characterization, and applications of them. This review aims to brief challenges that researchers or formulators may encounter when working with NEs. For instance, when selecting NE components and identifying their concentrations, stability and safety of the preparation should be evaluated. When preparing an NE, issues over scale-up of the preparation as well as possible effects of the preparation process on the active ingredient need to be considered. When characterizing the NEs, the two major concerns are accuracy of the method and accessibility of the characterizing instrument. Also a highly efficient NE for clinical use to deliver the active ingredient to the target tissue with maximum safety profile is commonly sought. Throughout the review we also have tried to suggest approaches to overcome the challenges. This article is categorized under: Therapeutic Approaches and Drug Discovery > Emerging Technologies.
Topics: Emulsions; Particle Size
PubMed: 37558229
DOI: 10.1002/wnan.1920 -
International Journal of Implant... Oct 2023The main purpose of this study was to evaluate whether large granular bovine bone can be as effective as small granular bovine bone in maxillary sinus floor elevation. (Meta-Analysis)
Meta-Analysis Review
OBJECTIVES
The main purpose of this study was to evaluate whether large granular bovine bone can be as effective as small granular bovine bone in maxillary sinus floor elevation.
METHODS
A comprehensive online search of eligible articles was conducted using PubMed, EMBASE, Cochrane Library, Scopus, and Web of Science, and a systematic review and meta-analysis was performed from establishment to February, 2023. The outcome indicators were the percentage of connective tissue, the percentage of newly formed bone and the percentage of residual xenograft respectively. The meta-analysis was conducted by using the Stata 15.1 (Stata Conpernarn, USA) and Review Manager software5.4.1.
RESULTS
After careful screening and review, a total of 4 studies were included for systematic review and meta-analysis. The data were extracted to compare the histological performance of bovine bones with different particle sizes after maxillary sinus elevation. No significant differences were found in the percentage of connective tissue, the percentage of newly formed bone, and the percentage of residual xenograft.
CONCLUSION
In this study, a systematically review of the previous literature showed that similar histological results were obtained for both large-particle bovine bone and small-particle bovine bone. Therefore, the large granular bovine bone and the small granular bovine bone were equally effective in maxillary sinus elevation. It is difficult to make conclusion from limited evidence from four studies. More clinical evidence was needed.
Topics: Humans; Animals; Cattle; Sinus Floor Augmentation; Bone Transplantation; Dental Implantation, Endosseous; Particle Size; Bone Substitutes
PubMed: 37782429
DOI: 10.1186/s40729-023-00502-1 -
Journal of Controlled Release :... Mar 2024The availability of analytical methods for the characterization of lipid nanoparticles (LNPs) for in-vivo intracellular delivery of nucleic acids is critical for the...
The availability of analytical methods for the characterization of lipid nanoparticles (LNPs) for in-vivo intracellular delivery of nucleic acids is critical for the fast development of innovative RNA therapies. In this study, analytical protocols to measure (i) chemical composition, (ii) drug loading, (iii) particle size, concentration, and stability as well as (iv) structure and morphology were evaluated and compared based on a comprehensive characterization strategy linking key physical and chemical properties to in-vitro efficacy and toxicity. Furthermore, the measurement protocols were assessed either by testing the reproducibility and robustness of the same technique in different laboratories, or by a correlative approach, comparing measurement results of the same attribute with orthogonal techniques. The characterization strategy and the analytical measurements described here will have an important role during formulation development and in determining robust quality attributes ultimately supporting the quality assessment of these innovative RNA therapeutics.
Topics: Reproducibility of Results; Lipids; RNA, Small Interfering; Nanoparticles; Liposomes; Particle Size; Nucleic Acids
PubMed: 38253203
DOI: 10.1016/j.jconrel.2024.01.037 -
Otolaryngology--head and Neck Surgery :... Dec 2023To determine whether hamster and human tissues generate similar amounts of aerosolized particles using common otolaryngology surgical techniques.
OBJECTIVE
To determine whether hamster and human tissues generate similar amounts of aerosolized particles using common otolaryngology surgical techniques.
STUDY DESIGN
Quantitative experimental research.
STUDY SETTING
University research laboratory.
METHODS
Drilling, electrocautery, and coblation were performed on human and hamster tissues. Particle size and concentration were measured during the surgical procedures using a scanning mobility particle sizer and an aerosol particle sizer (SMPS-APS) and GRIMM aerosol particle spectrometer.
RESULTS
SMPS-APS and GRIMM measurements detected at least 2-fold increases in aerosol concentrations compared to baseline during all procedures. Procedures performed on human and hamster tissues produced similar trends and order of magnitude of aerosol concentrations. Generally, hamster tissues produced higher aerosol concentrations compared to human tissues, and some of these differences were statistically significant. Mean particle sizes for all procedures were small (<200 nm), although statistically significant differences in particle size were identified between human and hamster tissues during coblation and drilling.
CONCLUSION
Aerosol-generating procedures performed on human and hamster tissue produce similar trends in aerosol particle concentrations and sizes, although we observed some differences between the 2 tissue types. Further studies should be performed to understand the clinical significance of these differences.
Topics: Animals; Humans; Particle Size; Nose; Aerosols; Otolaryngology
PubMed: 37313962
DOI: 10.1002/ohn.403 -
Ecotoxicology and Environmental Safety Jul 2023Gold nanoparticles (AuNPs) are widely used in biomedicine and their specific properties including, size, geometrics, and surface coating, will affect their fate and...
Gold nanoparticles (AuNPs) are widely used in biomedicine and their specific properties including, size, geometrics, and surface coating, will affect their fate and behaviour in biological systems. These properties are well studied for their intended biological targets, but there is a lack of understanding on the mechanisms by which AuNPs interact in non-target organisms when they enter the environment. We investigated the effects of size and surface chemistry of AuNPs on their bioavailability, tissue distribution and potential toxicity using zebrafish (Danio rerio) as an experimental model. Larval zebrafish were exposed to fluorescently tagged AuNPs of different sizes (10-100 nm) and surface modifications (TNFα, NHS/PAMAM and PEG), and uptake, tissue distribution and depuration rates were measured using selective-plane illumination microscopy (SPIM). The gut and pronephric tubules were found to contain detectable levels of AuNPs, and the concentration-dependent accumulation was related to the particle size. Surface addition of PEG and TNFα appeared to enhance particle accumulation in the pronephric tubules compared to uncoated particles. Depuration studies showed a gradual removal of particles from the gut and pronephric tubules, although fluorescence indicating the presence of the AuNPs remained in the pronephros 96 h after exposure. Toxicity assessment using two transgenic zebrafish reporter lines, however, revealed no AuNP-related renal injury or cellular oxidative stress. Collectively, our data show that AuNPs used in medical applications across the size range 40-80 nm, are bioavailable to larval zebrafish and some may persist in renal tissue, although their presence did not result in measurable toxicity with respect to pronephric organ function or cellular oxidative stress for short term exposures.
Topics: Animals; Zebrafish; Gold; Metal Nanoparticles; Tumor Necrosis Factor-alpha; Tissue Distribution; Biological Availability; Particle Size
PubMed: 37269610
DOI: 10.1016/j.ecoenv.2023.115019