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1.
Eur J Pharm Biopharm ; 203: 114456, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39153641

RESUMO

Moisture activated dry granulation (MADG) is an attractive granulation process. However, only a few works have explored modified drug release achieved by MADG, and to the best of the authors knowledge, none of them have explored gastroretention. The aim of this study was to explore the applicability of MADG process for developing gastroretentive placebo tablets, aided by SeDeM diagram. Floating and swelling capacities have been identified as critical quality attributes (CQAs). After a formulation screening step, the type and concentration of floating matrix formers and of binders were identified as the most relevant critical material attributes (CMAs) to investigate in ten formulations. A multiple linear regression analysis (MLRA) was applied against the factors that were varied to find the design space. An optimized product based on principal component analysis (PCA) results and MLRA was prepared and characterized. The granulate was also assessed by SeDeM. In conclusion, granulates lead to floating tablets with short floating lag time (<2 min), long floating duration (>4 h), and showing good swelling characteristics. The results obtained so far are promising enough to consider MADG as an advantageous granulation method to obtain gastroretentive tablets or even other controlled delivery systems requiring a relatively high content of absorbent materials in their composition.


Assuntos
Química Farmacêutica , Composição de Medicamentos , Liberação Controlada de Fármacos , Excipientes , Comprimidos , Composição de Medicamentos/métodos , Química Farmacêutica/métodos , Excipientes/química , Preparações de Ação Retardada , Solubilidade , Água/química , Análise de Componente Principal
2.
Brasília, D.F.; OPAS; 2024-08-14.
em Português | PAHO-IRIS | ID: phr2-61101

RESUMO

Para estabelecer medidas equivalentes para o ensaio de produtos de tabaco em escala mundial é necessário que haja métodos consensuais de medição do conteúdo e das emissões específicas dos cigarros. Nenhum regime de tragada obtido por máquinas é capaz de representar plenamente o comportamento humano de fumar: os ensaios realizados em máquinas de fumar são úteis para caracterizar as emissões de cigarro para fins de design e regulação, mas a divulgação aos fumantes das medições em máquinas pode resultar em interpretações equivocadas a respeito das diferenças de exposição e risco existentes entre as marcas. Os dados de emissão de fumaça obtidos por medições em máquinas podem ser usados como elementos para a avaliação do perigo do produto, mas não são e nem se destinam a ser medidas válidas de exposição ou risco para os seres humanos. A apresentação de diferenças nas medições em máquina como diferenças de exposição ou risco constitui uso indevido dos resultados do ensaio com métodos recomendados da TobLabNet da OMS. Este documento foi preparado por membros da Rede de Laboratórios de Tabaco (TobLabNet) da Organização Mundial da Saúde (OMS) como um procedimento operacional padrão (POP) de método analítico para determinação de umectantes no tabaco do cigarro.


Assuntos
Produtos do Tabaco , Fumar , Excipientes , Glicerol , Propilenoglicol , Testes de Toxicidade
3.
Drug Dev Ind Pharm ; 50(7): 646-657, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39072436

RESUMO

OBJECTIVE: This work aims to present a Quality-by-Design (QbD) step-by-step methodology to formulate anti-ulcer and gastro-protective oral suspensions. METHODS: Sucralfate was used as a drug model. The Quality Target Product Profile was established early during preformulation. Viscosity, resuspendability, pH, and density were assessed through the screening of several suspension platforms based on different prototype compositions. A compatibility study between the active pharmaceutical ingredient and the excipients was performed by thermal analysis and infrared spectroscopy. An Ishikawa fishbone diagram and Failure Mode and Effect Analysis were employed to identify the Critical Material Attributes (CMAs), Critical Process Parameters (CPPs), and Critical Quality Attributes (CQAs). CMAs' and CPPs' impact on identified CQAs was further assessed through a 22 full factorial experimental design at normal conditions after manufacture and one month at super-accelerated stress conditions. Results: The lead prototype exhibited no physicochemical incompatibilities. The risk assessment tools revealed that the concentration of the wetting agent and the total concentration of thickening agents represented critical factors for the quality profile of the preparation in terms of viscosity. The optimized formulation comprising 1.125 w/v% total concentration of Natrosol 250 HX and Avicel RC 591 exhibited an enhanced performance according to the established profile. CONCLUSIONS: The analytical and physicochemical tests showed the robustness and compliance of the final preparation with the quality profile. The proposed step-by-step methodology based on QbD, Design of Experiments, and Quality Risk Management presented in our research holds practical implications for local industries and formulation scientists involved in the development of oral suspensions.


Assuntos
Antiulcerosos , Química Farmacêutica , Composição de Medicamentos , Excipientes , Sucralfato , Suspensões , Antiulcerosos/administração & dosagem , Antiulcerosos/química , Viscosidade , Excipientes/química , Sucralfato/administração & dosagem , Sucralfato/química , Administração Oral , Composição de Medicamentos/métodos , Química Farmacêutica/métodos , Concentração de Íons de Hidrogênio
4.
AAPS PharmSciTech ; 25(5): 127, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38844724

RESUMO

The success of obtaining solid dispersions for solubility improvement invariably depends on the miscibility of the drug and polymeric carriers. This study aimed to categorize and select polymeric carriers via the classical group contribution method using the multivariate analysis of the calculated solubility parameter of RX-HCl. The total, partial, and derivate parameters for RX-HCl were calculated. The data were compared with the results of excipients (N = 36), and a hierarchical clustering analysis was further performed. Solid dispersions of selected polymers in different drug loads were produced using solvent casting and characterized via X-ray diffraction, infrared spectroscopy and scanning electron microscopy. RX-HCl presented a Hansen solubility parameter (HSP) of 23.52 MPa1/2. The exploratory analysis of HSP and relative energy difference (RED) elicited a classification for miscible (n = 11), partially miscible (n = 15), and immiscible (n = 10) combinations. The experimental validation followed by a principal component regression exhibited a significant correlation between the crystallinity reduction and calculated parameters, whereas the spectroscopic evaluation highlighted the hydrogen-bonding contribution towards amorphization. The systematic approach presented a high discrimination ability, contributing to optimal excipient selection for the obtention of solid solutions of RX-HCl.


Assuntos
Química Farmacêutica , Excipientes , Polímeros , Cloridrato de Raloxifeno , Solubilidade , Difração de Raios X , Polímeros/química , Excipientes/química , Cloridrato de Raloxifeno/química , Análise Multivariada , Difração de Raios X/métodos , Química Farmacêutica/métodos , Portadores de Fármacos/química , Composição de Medicamentos/métodos , Microscopia Eletrônica de Varredura/métodos , Ligação de Hidrogênio , Cristalização/métodos
5.
AAPS PharmSciTech ; 25(4): 79, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38589718

RESUMO

The development of suitable dosage forms is essential for an effective pharmacological treatment in children. Orally disintegrating tablets (ODTs) are attractive dosage forms that avoid swallowing problems, ensure dosage accuracy and are easy to administer as they disintegrate in the oral cavity. This study aimed to develop ODTs containing losartan potassium (LP) for the treatment of arterial hypertension in children. The ODTs, produced by the cost-effective manufacturing process of direct compression, consisted of a mixture of diluent, superdisintegrant, glidant and lubricant. Five superdisintegrants (croscarmellose sodium, two grades of crospovidone, sodium starch glycolate and pregelatinized starch) were tested (at two concentrations), and combined with three diluents (mannitol, lactose and sorbitol). Thus, thirty formulations were evaluated based on disintegration time, hardness and friability. Two formulations, exhibiting the best results concerning disintegration time (< 30 s), hardness and friability (≤ 1.0%), were selected as the most promising ones for further evaluation. These ODTs presented favourable drug-excipient compatibility, tabletability and flow properties. The in vitro dissolution studies demonstrated 'very rapid' drug release. Preliminary stability studies highlighted the requirement of a protective packaging. All quality properties retained appropriate results after 12 months of storage in airtight containers. In conclusion, the ODTs were successfully developed and characterised, suggesting a potential means to accomplish a final prototype that enables an improvement in childhood arterial hypertension treatment.


Assuntos
Hipertensão , Losartan , Humanos , Criança , Análise Custo-Benefício , Solubilidade , Administração Oral , Composição de Medicamentos/métodos , Excipientes , Hipertensão/tratamento farmacológico , Comprimidos , Dureza
6.
Drug Chem Toxicol ; 47(5): 507-515, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38326987

RESUMO

Tobacco stalk is a cellulose-rich material and a sustainable alternative to be applied as a plant-based nanofibrillated cellulose (NFC) source. NFC use has garnered attention in the development of oral pharmaceutical forms, despite concerns about its safety due to the adverse effects of nicotine on health. Therefore, we aimed at establishing the safety of NFC derived from tobacco stalk for its potential use as a novel pharmaceutical excipient, exploring its potential functions for tablet production. We conducted acute and subchronic oral toxicity tests in adult female Wistar rats. Initially, individual animals received sequential doses (175-5,000 mg·kg-1) for 24 hours followed by a careful observation of any toxic effects. Subsequently, 20 rats were divided into four groups for a subchronic assay, evaluating toxicity signs, body weight changes, hematological, biochemical, and histopathological parameters. No deaths or other clinical toxicity signs were observed in either the acute or the subchronic assays. We noticed a significant reduction in body weight gain (p < 0.05) after 14 days. We found statistical differences for hematological and biochemical parameters, unrelated to dosage. There were no observed toxic effects, and tobacco stalk ingestion did not adversely affect organ morphology in the histopathological evaluation. The oral administration of NFC at 5,000 mg·kg-1 per day for 28 days was well-tolerated by treated rats, with no reported deaths. In conclusion, NFC derived from tobacco stalk has shown to be a sustainable and safe alternative for use as an excipient at experimental doses, demonstrating compatibility with its proposed applications.


Assuntos
Celulose , Excipientes , Nicotiana , Ratos Wistar , Animais , Feminino , Celulose/toxicidade , Celulose/administração & dosagem , Celulose/química , Excipientes/toxicidade , Excipientes/química , Administração Oral , Testes de Toxicidade Subcrônica , Ratos , Testes de Toxicidade Aguda , Nanofibras/toxicidade , Química Verde , Relação Dose-Resposta a Droga
7.
Int J Biol Macromol ; 263(Pt 1): 130230, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38373564

RESUMO

Pectin is widely used in several products in the industry. Conventionally, strong and harmful acids are used for its extraction. This study optimized the extraction of orange peel's pectin using citric acid, considering yield and degree of esterification (DE) as response variables. Proximal analyses were performed, and the samples were subjected to a Box-Behnken design on three central points, considering as variables the temperature, time, and pH. The results of proximate analyses of the orange peels revealed 11.76 % moisture content, 87.26 % volatiles, 0.09 % ash, 50.45 % soluble carbohydrates, 70.60 % total carbohydrates, 0.89 % fixed carbon, 5.35 % lipids, and 36.75 mg GAE/g of phenolic compounds. The resulting second-order polynomial model described the relation of the input and output variables related to each other. The best performance to obtain a higher yield (18.18 %) of high methoxyl pectin (DE 50 %) was set at 100 °C/30 min/pH 2.48. Pectin showed antioxidant properties by ABTS and DPPH assays and similar thermal properties to the commercial polymer. Its equivalent weight was 1219.51 mol/g, and the methoxyl and anhydrouronic acid were 2.23 and 67.10 %, respectively. Hence, pectin extraction with citric acid results in a high-quality polymer and could be used as a gelling agent, stabilizer, or texturizer in food products.


Assuntos
Citrus sinensis , Pectinas , Pectinas/química , Citrus sinensis/química , Ácido Cítrico/química , Temperatura , Antioxidantes/farmacologia , Excipientes
8.
Int J Pharm ; 652: 123849, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38266938

RESUMO

This feasibility study evaluates a cleaning process designed to avoid the use of detergents and reduce operator exposure to the active pharmaceutical ingredient (API). The continuous manufacturing equipment was cleaned using excipients to displace ibuprofen residues from the system. The cleaning process was performed using 3.0 kg of Prosolv® and 3.0 kg of Tablettose® 70. The impact of different volumetric feed rates of the cleaning excipient was assessed. The displacement of API and blend residues was evaluated with in-line near infrared (NIR) spectroscopy. Principal component analysis (PCA) was performed to evaluate the cleaning progress as the Prosolv® flowed through the feeder, mixer and stream sampler. In-place Raman spectra were acquired from the material sticking to detect the ibuprofen residues. The study showed that Prosolv® and Tablettose® can remove ibuprofen residues effectively from the hopper, feeder screw, mixer paddles, shaft and stream sampler. The Process Analytical Technology (PAT) system can be utilized to detect API displacement during the cleaning process. However, dismantling and manual cleaning was required to remove material sticking at the surfaces adjacent to the rotating feeder screws and mixer paddles.


Assuntos
Química Farmacêutica , Tecnologia Farmacêutica , Tecnologia Farmacêutica/métodos , Química Farmacêutica/métodos , Excipientes/química , Ibuprofeno/química , Pós/química , Comprimidos , Composição de Medicamentos/métodos
9.
Curr Microbiol ; 80(12): 372, 2023 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-37843653

RESUMO

Phage therapy is a promising alternative to control bacterial diseases and the increasing problem of antibiotic resistance. In this sense, this research evaluates the viability of lyophilized vibrio phage vB_Pd_PDCC-1 using trehalose as a preservative excipient at different concentrations (4, 2, 1, and 0.5% w/v) and its potential for phage therapy application against a pathogenic bacteria Vibrio diabolicus in brine shrimp nauplii (Artemia franciscana). The lyophilized phages were stored at 4 and 23 °C and rehydrated using biological sterile saline solution to test their viability at days 1, 15, and 60 post-lyophilization. The results showed that trehalose is beneficial in maintaining the viability of post-lyophilization phages (without titer losses) at 4 °C and even at room temperature (23 °C). When lyophilized phages with 4% w/v trehalose concentration were stored at 23 °C, they had not titer losses among the trials; viability and titer concentration were maintained up to 60 days at log 7. The use of lyophilized phage PDCC-1 increased brine shrimp survival and reduced Vibrio concentrations. The present study has identified trehalose as a promising lyophilization excipient to effectively preserve lyophilized bacteriophages for biotechnological applications and long-term storage.


Assuntos
Bacteriófagos , Vibrio , Trealose/farmacologia , Excipientes , Myoviridae
10.
Int J Nanomedicine ; 18: 5891-5904, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37873551

RESUMO

Introduction: Chimeric antigen receptor (CAR) cell therapy represents a hallmark in cancer immunotherapy, with significant clinical results in the treatment of hematological tumors. However, current approved methods to engineer T cells to express CAR use viral vectors, which are integrative and have been associated with severe adverse effects due to constitutive expression of CAR. In this context, non-viral vectors such as ionizable lipid nanoparticles (LNPs) arise as an alternative to engineer CAR T cells with transient expression of CAR. Methods: Here, we formulated a mini-library of LNPs to deliver pDNA to T cells by varying the molar ratios of excipient lipids in each formulation. LNPs were characterized and screened in vitro using a T cell line (Jurkat). The optimized formulation was used ex vivo to engineer T cells derived from human peripheral blood mononuclear cells (PBMCs) for the expression of an anti-CD19 CAR (CAR-CD19BBz). The effectiveness of these CAR T cells was assessed in vitro against Raji (CD19+) cells. Results: LNPs formulated with different molar ratios of excipient lipids efficiently delivered pDNA to Jurkat cells with low cytotoxicity compared to conventional transfection methods, such as electroporation and lipofectamine. We show that CAR-CD19BBz expression in T cells was transient after transfection with LNPs. Jurkat cells transfected with our top-performing LNPs underwent activation when exposed to CD19+ target cells. Using our top-performing LNP-9-CAR, we were able to engineer human primary T cells to express CAR-CD19BBz, which elicited significant specific killing of CD19+ target cells in vitro. Conclusion: Collectively, our results show that LNP-mediated delivery of pDNA is a suitable method to engineer human T cells to express CAR, which holds promise for improving the production methods and broader application of this therapy in the future.


Assuntos
Excipientes , Nanopartículas , Humanos , Leucócitos Mononucleares , Plasmídeos/genética , DNA/genética , Lipídeos
11.
Food Res Int ; 172: 113099, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37689863

RESUMO

Rice protein isolate (RPI) has been receiving increasing attention from the food industry due to its performance as an emulsifier. However, it is possible to enlarge its field of applications through enzymatic hydrolysis. Therefore, this work aimed to investigate the effects of the controlled enzymatic hydrolysis (degree of hydrolysis DH as 2, 6, and 10%) using Flavourzyme on the physicochemical properties of rice protein and to identify the minimum concentration of these hydrolysates (0.5, 1.0, and 1.5%) to form and stabilize oil/water emulsion. The physicochemical, interfacial tension (IT), and surface characteristics of RPI and their hydrolysates (RPH) were determined. Even at a lower protein concentration (1.0%), protein hydrolysate presented lower IT when compared with RPI at a higher protein concentration (1.5%). The interfacial tension decreased from 17.6 mN/m to 9.9 mN/m when RPI was hydrolyzed. Moreover, enzymatic hydrolysis (DH 6 and 10%) enhanced the protein solubility by almost 20% over a pH range of 3-11. The improved amphiphilic property of RPH, supported by the results of IT and solubility, was confirmed by the higher emulsion stability indicated by the Turbiscan and emulsion stability indexes. Emulsions stabilized by RPH (DH 6% and 10%) at lower protein concentrations (1%) exhibited better physical stability than RPI at higher protein concentrations (1.5%). In this work, we verified the minimum concentration of rice protein hydrolysate required to form and stabilize oil-in-water (O/W) emulsions.


Assuntos
Oryza , Hidrolisados de Proteína , Excipientes , Emulsões , Emulsificantes
12.
J Pharm Biomed Anal ; 235: 115634, 2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37595356

RESUMO

Monoglycerides (MGs) such as glycerol monolaurate (GML) and glycerol monostearate (GMS) have been used as excipients in oral formulations because of their emulsifying effect as well as their ability to inhibit the precipitation and intestinal efflux of drugs. Excipient-drug compatibility studies, however, have been underexplored. In this study, benznidazole (BNZ) was selected as a drug model due to the difficulty in improving its solubility and because of the potential impact on public health (it is the only drug currently used to treat Chagas disease). The effect of different processing conditions (maceration, ball milling, and melting) on the physical-chemistry properties of BNZ/MGs mixtures was investigated to guide the rational development of new solid formulations. GML was more effective in improving the solubility of BNZ, which could be due to its more malleable structure, less hydrophobic nature, and greater interaction with BNZ. The formation of hydrogen bonds between the imidazole group of BNZ and the polar region of GML was confirmed by spectroscopy analyses (IR, 1H NMR). The higher the monoglyceride content in the mixture, the higher the BNZ solubility. Regardless of the method of processing the mixture, the drug was found to be crystalline. Polarized light microscopy analysis showed the presence of spherulites. Overall, these findings suggest that preparation methods of BNZ:MGs formulations that involve thermal or/and mechanical treatment have a low impact on the solid properties of the material, and this allows for the production of formulations with reproducible performance.


Assuntos
Monoglicerídeos , Nitroimidazóis , Excipientes , Glicerídeos
13.
Pharm Dev Technol ; 28(8): 768-784, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37632372

RESUMO

Skin disorders are preferentially treated by topical administration of medicines or cosmetics because of the possibility of local action. However, a great concern is the delivery of topical actives with effective penetration through the stratum corneum to ensure the desired effect. Considering the search for a carrier system that allows the penetration/permeation of active pharmaceutical ingredients through this structure, searching for effective topical pharmaceutical forms is needed. Foams have been widely studied over the years due to their high capacity to favor the active to overcome the cutaneous barrier and because this form of presentation has ease of application and high acceptability by users. The objective of this review was to analyze the potential of foam as a topical pharmaceutical form for treating skin disorders, upon clinical cases reported in the literature. Foam presents technical advantages when compared to other conventional topical pharmaceutical forms due to its fast action, high tolerance, and safety, with reduction or total remission of adverse events. Regarding the patient, foam increased the rate of adherence to the treatment. Therefore, it is concluded that foam is an effective, secure, and stable topical presentation form for carrying active pharmaceutical ingredients and widely accepted by patients.


Assuntos
Dermatopatias , Humanos , Preparações Farmacêuticas , Administração Tópica , Dermatopatias/tratamento farmacológico , Epiderme , Excipientes , Administração Cutânea , Pele
14.
AAPS PharmSciTech ; 24(6): 159, 2023 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-37498506

RESUMO

The development of formulations adapted to the patient's age is a challenge in the pharmaceutical industry. Pediatric and geriatric patients may have difficulties in swallowing oral medications when an adequate formulation is not available. Carvedilol is a poorly water-soluble drug used to treat cardiovascular problems; it is commercialized in several countries only as solid oral formulations, which are often manipulated at the point of administration to treat pediatric or geriatric patients. The purpose of this work was to obtain a new dosage form of Carvedilol using safe excipients, suitable for administration to pediatric and geriatric patients. To improve the solubility of Carvedilol, the effect of several factors was analyzed and optimized. Subsequently, to improve the physical stability of the formulations, two preparation methods were analyzed by adding HPMC. In "method 1," HPMC was dissolved in buffer and incorporated into a mixture of Carvedilol-PEG 400, while in "method 2," Carvedilol was solubilized in buffer containing PEG 400, and then, HPMC was added. Finally, microbiological tests were performed to the stable formulations. The factors "pH value" and "concentration of PEG" affected the solubility of Carvedilol. A formulation containing Carvedilol (3 mg/mL), pH=3, PEG 400 (15% v/v), and HPMC (0.25% w/v) prepared by method 2 was stable for 180 days at 4 °C while those containing Carvedilol (5 mg/mL), pH=3, PEG 400 (27% v/v), and HPMC (0.5% w/v), prepared by method 2, were stable for 180 days at 4 and 25°C. These oral liquid formulations were physicochemical and microbiologically stable for 6 months.


Assuntos
Excipientes , Polietilenoglicóis , Humanos , Criança , Idoso , Carvedilol , Solubilidade , Estabilidade de Medicamentos , Administração Oral
15.
Expert Opin Drug Deliv ; 20(7): 979-992, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37522812

RESUMO

INTRODUCTION: Although the administration of drugs on the skin is a safe and noninvasive therapeutic alternative, producing formulations capable of disrupting the cutaneous barriers is still a challenge. In this scenario, extrusion-based techniques have emerged as disruptive technologies to ensure unique drug-excipient interactions that facilitate drug skin diffusion for systemic or local effect and even mean the key to obtain viable industrial products. AREAS COVERED: This article presents a comprehensive overview of extrusion-based techniques in developing pharmaceutical dosage forms for topical or transdermal drug delivery. First, the theoretical basis of how extrusion-based techniques can optimize the permeation of drugs through the skin is examined. Then, the current state-of-the-art of drug products developed by extrusion-based techniques, specifically by hot-melt extrusion (HME) and fused deposition modeling (FDM) 3D printing, are discussed and contrasted with the current pharmaceutical processes. EXPERT OPINION: A wide variety of pharmaceutical products can be obtained using HME and FDM 3D printing, including new dosage forms designed for a perfect anatomical fit. Despite the limitations of pharmaceutical products produced with HME and FDM 3D printing regarding thermal stability and available excipients, the advantages in industrial adaptability and improved bioavailability allied with patient-match devices certainly deserve full attention and investment.


Assuntos
Tecnologia de Extrusão por Fusão a Quente , Tecnologia Farmacêutica , Humanos , Tecnologia Farmacêutica/métodos , Preparações Farmacêuticas , Composição de Medicamentos/métodos , Administração Cutânea , Excipientes , Liberação Controlada de Fármacos , Sistemas de Liberação de Medicamentos/métodos , Comprimidos
16.
Sci Rep ; 13(1): 10651, 2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37391489

RESUMO

This study demonstrates a full-color near-eye holographic display capable of superimposing color virtual scenes with 2D, 3D, and multiple objects with extended depth upon a real scene, which also has the ability to present different 3D information depending on the focus of the user's eyes using a single computer-generated hologram per color channel. Our setup makes use of a hologram generation method based on two-step propagation and the singular value decomposition of the Fresnel transform impulse response function to efficiently generate the holograms of the target scene. Then, we test our proposal by implementing a holographic display that makes use of a phase-only spatial light modulator and time-division multiplexing for color reproduction. We demonstrate the superior quality and computation speed of this approach compared with other hologram generation techniques with both numerical and experimental results.


Assuntos
Realidade Aumentada , Holografia , Olho , Excipientes , Cor de Olho
17.
An Acad Bras Cienc ; 95(2): e20211598, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37341271

RESUMO

Despite being little explored for petroporphyrins recovery from oils and bituminous shales, adsorption and desorption processes can be feasible alternatives to obtain a similar synthetic material, and to characterize their original organic materials. Experimental designs were used to analyze the effects of qualitative (e.g., type of adsorbent, solvent, and diluent) and quantitative (e.g., temperature and solid/liquid ratio) variables on the adsorptive and desorptive performance regarding nickel octaethylporphyrin (Ni-OEP) removal using carbon-based adsorbents. The evaluation variables, adsorption capacity (qe ) and desorption percentage (%desorption ) were optimized by means of the Differential Evolution algorithm. The most efficient adsorbent for removing/recovery Ni-OEP was activated-carbon coconut shell, in which dispersive π-π type and acid-base interactions were likely formed. The highest values of qe and %desorption were obtained using toluene as solvent, chloroform as diluent, 293 K as temperature, and 0.5 mg.mL-1 as solid/liquid ratio for adsorption, and a higher temperature (323 K) and lower solid/liquid ratio (0.2 mg.mL-1) for desorption. The optimization process resulted in qe of 6.91 mg.g-1 and %desorption of 35.2%. In the adsorption-desorption cycles, approximately 77% of the adsorbed porphyrins were recovered. The results demonstrated the potential of carbon-based materials as adsorbent materials for obtaining porphyrin compounds from oils and bituminous shales.


Assuntos
Níquel , Porfirinas , Carbono , Adsorção , Excipientes , Solventes
18.
AAPS PharmSciTech ; 24(4): 97, 2023 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-37016118

RESUMO

The evaluation of the vehicle formulation is important during the development of sunscreens, as it influences their efficacy. In this context, the aim of the present study was to develop photoprotective formulations and evaluate the influence of the formulation components in the sun protection factor (SPF) and physical-mechanical and sensory properties of the formulations. We evaluated four sunscreens through a 22 full factorial design in terms of concentration and emulsifier type. The design of experiments (DOE) parameters were SPF, thixotropy, and work of shear. After the screening of the formulations by DOE, the SPF values, mechanical and sensory properties, and stability were evaluated. All study formulations showed non-Newtonian pseudoplastic behavior, compatible with sunscreens, and presented SPF values above 30. The factors evaluated in DOE had significant interactions for all the analyzed parameters. The concentration of the phosphate-based emulsifier influenced the SPF parameter. The work of shear was influenced by the concentration of polyglyceryl-based emulsifier. The concentration and the type of emulsifier influenced the thixotropy. Finally, effective sunscreens were developed, and the type and concentration of emulsifiers had an influence on the SPF of the formulations. In addition, the formulations chosen by DOE were stable and showed good sensory properties.


Assuntos
Fator de Proteção Solar , Protetores Solares , Emulsificantes , Excipientes , Raios Ultravioleta
19.
Int J Mol Sci ; 24(6)2023 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-36982517

RESUMO

Microparticulate systems such as microparticles, microspheres, microcapsules or any particle in a micrometer scale (usually of 1-1000 µm) are widely used as drug delivery systems, because they offer higher therapeutic and diagnostic performance compared to conventional drug delivery forms. These systems can be manufactured with many raw materials, especially polymers, most of which have been effective in improving the physicochemical properties and biological activities of active compounds. This review will focus on the in vivo and in vitro application in the last decade (2012 to 2022) of different active pharmaceutical ingredients microencapsulated in polymeric or lipid matrices, the main formulation factors (excipients and techniques) and mostly their biological activities, with the aim of introducing and discussing the potential applicability of microparticulate systems in the pharmaceutical field.


Assuntos
Sistemas de Liberação de Medicamentos , Polímeros , Composição de Medicamentos/métodos , Sistemas de Liberação de Medicamentos/métodos , Polímeros/química , Excipientes , Cápsulas , Microesferas , Tamanho da Partícula
20.
Braz. J. Pharm. Sci. (Online) ; 59: e22505, 2023. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1439507

RESUMO

Abstract Natural products are considered an important source of the therapeutic arsenal currently available. Among these alternatives are the seeds of Ambrosia peruviana (altamisa), whose extract has shown an anti-inflammatory effect. The main objective of this work was to perform a preformulation study of Ambrosia peruviana seeds ethanolic extract, where the main factors that affect the physical, chemical, and pharmacological stability of the extract were evaluated, as well as a compatibility study by differential scanning calorimetry (DSC) analysis against different excipients. A dry extract was obtained by rotary evaporation of the seeds macerated with 96% ethanol. The anti-inflammatory activity was determined by measuring its effect on NO production in RAW 264.7 macrophages, stimulated with LPS. The results showed that the dry extract maintained its stability over time when stored at a temperature of 4 and 25ºC, demonstrating its biological activity, the content of phenolic compounds, and its physicochemical parameters remain practically invariable. However, when exposed to high temperatures (60 ºC) it was affected. The thermal analysis revelated that the behavior of most of the selected excipients and the dry extract was maintained, which indicates that it did not present incompatibilities, therefore they can be candidates for formulating a microemulsion.


Assuntos
Sementes/metabolismo , Asteraceae/classificação , Ambrosia/efeitos adversos , Produtos Biológicos , Varredura Diferencial de Calorimetria/métodos , Excipientes/administração & dosagem
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