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1.
EFSA J ; 21(Suppl 1): e211008, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38047132

RESUMO

Plastics are ubiquitously, becoming part of our everyday life. Recently, the issue of human exposure to micro- and nanoplastic particles and potentially resulting toxicological consequences has been broached, triggered by the discovery of microplastics in foodstuff and dietary exposure via contaminated food and beverages. Within this EU-FORA fellowship project, a determination and quantification of plastic polyester plastics oligomers in food samples was performed to assess exposure at these categories of 'nanoplastics', evaluating them as potential contaminants or as indicators and marker compounds of the exposure to specific nanoplastics/microplastics from polyesters, such as polyethylene terephthalate (PET) and polybutylene terephthalate (PBT). UHPLC-TOF-MS/MS analysis has been set-up for 10 PET and PBT oligomers and analysis has been performed in foods and drinks. Moreover, the project focused also on the effects of these oligomers in in vitro and ex vivo experiments. These data would be combined with EFSA Comprehensive Food Consumption Database, for the exposure and risk assessment of these 'Nanoplastics'.

2.
Int J Pharm ; 616: 121512, 2022 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-35085730

RESUMO

The study aimed to fabricate naproxen sodium loaded in-situ gels of sodium alginate. Different in-situ gel forming solutions of naproxen sodium and sodium alginate were prepared and gel formation was studied in different physiological ions i.e., CaCl2 and Ca-gluconate. The prepared gel formulations were evaluated for different physical attributes such as gelation time, sol-gel fraction, ATR-FTIR spectroscopy and in silico molecular dynamics (MD) simulations. Drug release studies were carried out in a dialysis membrane using USP dissolution basket apparatus-I. In vivo anti-inflammatory studies were performed in Sprague-Dawley rats having carrageenan-induced hind paw inflammation. Higher polymer concentration in formulations resulted in decreased gelation time and an increased gel fraction. The ATR-FTIR and MD simulation revealed H-bonding between the alginate and naproxen sodium at 3500-3200 cm-1 with a RMSD of ∼2.8 Å and binding free energy ΔGpred (GB) = -10.93 kcal/mol. In vitro drug release studies from F8CAG suggested a sustained release of naproxen sodium. In vivo studies revealed a continuous decrease in swelling degree (≈-5.28 ± 0.210 mm) in inflamed hind paw of Sprague-Dawley rats over 96 h. The in-situ gel forming injectable preparation (F8CAG) offers a sustained release of naproxen sodium in the articular cavity which promises the treatment of chronic inflammatory conditions such as arthritis.


Assuntos
Naproxeno , Diálise Renal , Animais , Preparações de Ação Retardada , Géis/química , Naproxeno/química , Ratos , Ratos Sprague-Dawley
3.
Daru ; 27(2): 673-681, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31630328

RESUMO

PURPOSE: The aim of this study was to design and characterize microneedle patch formulation containing cetirizine hydrochloride. METHODS: Chitosan was co-formulated with cetirizine hydrochloride. Transdermal patches were prepared by casting this solution to microneedle molds. Control patches were formulated by casting this solution to a plain cuvet of same area as mold but lacking microneedles. An array of methods namely; differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and scanning electron microscopy (SEM) were employed for the characterization of the films and the microneedles accordingly whereas in vitro permeation studies were conducted across rat skin. Light microscopy was performed to assess any histological changes upon microneedles application onto the rat skin. RESULTS: The patches had a reproducible thickness (0.86 ± 0.06 mm) and folding endurance. Both the blank and drug loaded patches had 100 microneedles each of 300 micrometre length. In addition, the microneedle patches were ascribed with a two-fold increase in drug permeation across rat skin in the presence of microneedles as compared to the control formulations. Histological examination confirms a minimal invasion of the skin conferred by the microneedles. CONCLUSION: The microneedle patches serve as an alternate route of drug administration in patients with nausea and swelling difficulties. Graphical abstract Microneedle patch manifest a two-fold increase in the skin permeation of Cetirizine Hydrochloride as compared to the control that is drug loaded patch without microneedles.


Assuntos
Cetirizina/farmacocinética , Quitosana/química , Microtecnologia/instrumentação , Animais , Varredura Diferencial de Calorimetria , Microscopia Eletrônica de Varredura , Agulhas , Ratos , Termogravimetria , Adesivo Transdérmico
4.
AAPS PharmSciTech ; 19(2): 741-752, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28980185

RESUMO

In the present study, liquisolid formulations were developed for improving dissolution profile of aprepitant (APT) in a solid dosage form. Experimental studies were complemented with artificial neural networks and genetic programming. Specifically, the type and concentration of liquid vehicle was evaluated through saturation-solubility studies, while the effect of the amount of viscosity increasing agent (HPMC), the type of wetting (Soluplus® vs. PVP) and solubilizing (Poloxamer®407 vs. Kolliphor®ELP) agents, and the ratio of solid coating (microcrystalline cellulose) to carrier (colloidal silicon dioxide) were evaluated based on in vitro drug release studies. The optimum liquisolid formulation exhibited improved dissolution characteristics compared to the marketed product Emend®. X-ray diffraction (XRD), scanning electron microscopy (SEM) and a novel method combining particle size analysis by dynamic light scattering (DLS) and HPLC, revealed that the increase in dissolution rate of APT in the optimum liquisolid formulation was due to the formation of stable APT nanocrystals. Differential scanning calorimetry (DSC) and attenuated total reflection FTIR spectroscopy (ATR-FTIR) revealed the presence of intermolecular interactions between APT and liquisolid formulation excipients. Multilinear regression analysis (MLR), artificial neural networks (ANNs), and genetic programming (GP) were used to correlate several formulation variables with dissolution profile parameters (Y 15min and Y 30min) using a full factorial experimental design. Results showed increased correlation efficacy for ANNs and GP (RMSE of 0.151 and 0.273, respectively) compared to MLR (RMSE = 0.413).


Assuntos
Morfolinas/administração & dosagem , Aprepitanto , Celulose , Liberação Controlada de Fármacos , Excipientes/química , Morfolinas/química , Redes Neurais de Computação , Tamanho da Partícula , Polietilenoglicóis , Polivinil , Análise de Regressão , Dióxido de Silício/química , Solubilidade
5.
J Drug Target ; 23(4): 305-10, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25582133

RESUMO

A scalable platform to prepare multi-functional ocular lenses is demonstrated. Using rapidly dissolving polyvinylpyrrolidone (PVP) as the active stabilizing matrix, both sides of ocular lenses were coated using a modified scaled-up masking electrohydrodynamic atomization (EHDA) technique (flow rates variable between 5 and 10 µL/min, applied voltage 4-11 kV). Each side was coated (using a specially designed flip-able well) selectively with a pre-determined morphology and model drug substance. PVP nanoparticles (inner side, to be in contact with the cornea, mean size

Assuntos
Cloranfenicol/administração & dosagem , Sistemas de Liberação de Medicamentos , Lentes Intraoculares , Nanopartículas , Antibacterianos/administração & dosagem , Antibacterianos/farmacologia , Química Farmacêutica/métodos , Cloranfenicol/farmacologia , Excipientes/química , Tamanho da Partícula , Polímeros/química , Povidona/química , Staphylococcus aureus/efeitos dos fármacos , Temperatura
6.
Drug Discov Today ; 17(3-4): 153-9, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21978988

RESUMO

The early promise of boron neutron capture therapy as a method for the treatment of cancer has been inhibited by the inherent toxicity associated with therapeutically useful doses of ¹°B-containing pharmacophores, the need for target-tissue specificity and the challenges imposed by biological barriers. Although developments in the synthetic chemistry of polyhedral boranes have addressed issues of toxicity to a considerable extent, the optimisation of the transport and the delivery of boronated agents to the site of action--the subject of this review--is a challenge that is addressed by the development of innovative formulation strategies.


Assuntos
Boranos/química , Terapia por Captura de Nêutron de Boro/métodos , Neoplasias/radioterapia , Animais , Transporte Biológico , Boranos/farmacocinética , Compostos de Boro/efeitos adversos , Compostos de Boro/química , Compostos de Boro/farmacocinética , Terapia por Captura de Nêutron de Boro/efeitos adversos , Humanos
7.
J Pharm Sci ; 99(8): 3522-32, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20564382

RESUMO

The purpose of the present study was to study the impact of free fatty acid and monoglyceride level and ratio on the nanostructural composition and solubilizing capacity of media simulating fed state intestinal fluids (SIFs). SIFs, without or with oleic acid/monoolein (OA/MO) in ratios of 2:1 or 6:1 were composed and characterized by surface tension, dynamic light scattering, and cryogenic transmission electron microscopy. Additionally solubilizing capacities towards three poorly water-soluble compounds: danazol, fenofibrate, and cinnarizine, were assessed. The surface tension of the media was not affected by the OA/MO ratio but only determined by the total surfactant concentration. The media with no lipolysis products only contained micelles, whereas media with lipolysis products also contained vesicles and other colloidal structures. The structures in the 6:1 media were more numerous and more well-defined regarding shape and size. The nanostructural composition of the media did influence the solubilizing capacity toward fenofibrate and cinnarizine, but not toward danazol. The relative composition of SIFs is important for the solubilizing capacity of some drug compounds. The findings in this study suggest that the affinity of the drug to the different colloidal structures is determining for the solubility of the compound in the media.


Assuntos
Mucosa Intestinal/metabolismo , Algoritmos , Bile/química , Líquidos Corporais/metabolismo , Cromatografia Líquida de Alta Pressão , Cinarizina/química , Coloides , Danazol/química , Emulsões , Ácidos Graxos não Esterificados/química , Fenofibrato/química , Luz , Micelas , Microscopia Eletrônica de Transmissão , Monoglicerídeos/química , Tamanho da Partícula , Espalhamento de Radiação , Solubilidade , Soluções , Tensão Superficial
8.
J Nanosci Nanotechnol ; 6(9-10): 2618-37, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17048471

RESUMO

Natural and synthetic arsenolipids, have been discovered, synthesized, and evaluated for their biological activity. Arsonolipids, are analogs of phosphonolipids, in which P has been replaced by As. The synthesis of arsonolipids has been explored and a simple one-pot method with high yield is currently available for their preparation. However, although arsonolipids posses interesting biophysical and biochemical properties their anticancer or antiparasitic activity is not considered adequate for therapeutic applications. But when arsonolipids are incorporated in liposomes, the vesicles formulated have interesting possibilities, as seen in a number of studies. In cell culture studies, nanosized arsonolipid-containing liposomes or else arsonoliposomes, showed increased toxicity against cancer cells (compared to that of arsenic trioxide) but at the same time were less toxic than arsenic trioxide for normal cells. Furthermore, arsonoliposomes also demonstrate antiparasitic activity in vitro. Nevertheless, As is rapidly cleared from blood after in vivo administration of arsonoliposomes, and this will highly limit possible therapeutic applications. In addition, the fact that arsonoliposomes were observed to aggregate and subsequently fuse into larger particles in presence of cations, may also be considered as a problem. Thereby, methods to modulate the stability of arsonoliposomes and, perhaps, their in vivo distribution (as surface property modification) are currently being investigated. In very recent experiments it has been shown that arsonoliposome pegylation results in the formation of liposomes with very high membrane integrity. In addition, pegylation results in increased physical stability of arsonoliposomes and abolishment of cation-induced aggregation and fusion. Nevertheless, further in vivo studies are required in order to prove if pegylation alters arsonoliposome in vivo kinetics in a positive way, without affecting their activity. From studies performed thus far it is concluded that arsonoliposomes are nanosized-vesicles with interesting properties that justify further exploitation towards the development of therapeutic systems for cancer or parasitic diseases.


Assuntos
Arsênio/administração & dosagem , Arsênio/química , Materiais Revestidos Biocompatíveis/química , Cristalização/métodos , Portadores de Fármacos/química , Lipossomos/química , Nanoestruturas/química , Sistemas de Liberação de Medicamentos/métodos , Eletroquímica/métodos , Nanoestruturas/ultraestrutura , Tamanho da Partícula , Rotação
9.
Chem Phys Lipids ; 139(2): 96-106, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16405880

RESUMO

We investigated the effect of pegylation on the physical stability, morphology and membrane integrity of arsonoliposomes. Arsonoliposomes composed of distearoylglycerophosphocholine (DSPC), cholesterol (Chol) and the palmitoyl side chain arsonolipid (with concentrations ranging from 0 mol% [DSPC/Chol vesicles] to 53 mol% of total lipid) containing either 4 or 8 mol% DPPE-PEG2000 or DSPE-PEG2000, were prepared by sonication. Arsonoliposome membrane integrity was evaluated by measuring the retention of encapsulated calcein in vesicles (during incubation in buffer or fetal calf serum [FCS]) while physical stability was evaluated by measuring vesicle dispersion turbidity (during incubation in water or CaCl(2)). Vesicle morphology was studied by cryo-electron microscopy. Experimental results show that: (i) PEG-lipids are incorporated in arsonoliposomes (as confirmed by the vesicle zeta potential modulation), (ii) pegylation of arsonoliposomes prevents their aggregation and fusion in the presence of calcium ions and (iii) when 8 mol% of PEG-DSPE is incorporated in arsonoliposomes based on their arsonolipid content, two groups of pegylated vesicles are formed: low content arsonoliposomes (<20 mol% arsonolipid) which are highly leaky and high content arsonoliposomes (>27 mol% arsonolipid) which are highly stable (70% calcein retention after 24h incubation in fetal calf serum [FCS]). In addition to high membrane integrity, the high content pegylated arsonoliposomes are morphologically perfect round-shaped vesicles without the sharp edges typically observed with non-pegylated DSPC-containing arsonoliposomes.


Assuntos
Arsênio/química , Lipídeos/química , Lipossomos/química , Polietilenoglicóis/química , Fenômenos Químicos , Físico-Química , Colesterol/química , Membranas Artificiais , Ácido Palmítico/química , Fosfatidilcolinas/química , Fosfatidiletanolaminas/química , Fatores de Tempo
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