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1.
Adv Drug Deliv Rev ; 175: 113823, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34089777

RESUMO

Advancements in technology and material development in recent years has led to significant breakthroughs in the remit of fiber engineering. Conventional methods such as wet spinning, melt spinning, phase separation and template synthesis have been reported to develop fibrous structures for an array of applications. However, these methods have limitations with respect to processing conditions (e.g. high processing temperatures, shear stresses) and production (e.g. non-continuous fibers). The materials that can be processed using these methods are also limited, deterring their use in practical applications. Producing fibrous structures on a nanometer scale, in sync with the advancements in nanotechnology is another challenge met by these conventional methods. In this review we aim to present a brief overview of conventional methods of fiber fabrication and focus on the emerging fiber engineering techniques namely electrospinning, centrifugal spinning and pressurised gyration. This review will discuss the fundamental principles and factors governing each fabrication method and converge on the applications of the resulting spun fibers; specifically, in the drug delivery remit and in regenerative medicine.


Assuntos
Engenharia Biomédica/métodos , Sistemas de Liberação de Medicamentos/métodos , Ciência dos Materiais/métodos , Medicina de Precisão/métodos , Medicina Regenerativa/métodos , Centrifugação , Fenômenos Eletromagnéticos , Humanos , Pressão
2.
J Drug Target ; 28(5): 525-532, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31718314

RESUMO

The aim of this study was to fabricate Bacillus Calmette-Guérin (BCG)-loaded microneedle patches using micromould casting technique and compare their efficacy with the injectable counterparts. The microneedle patches were formulated using sodium alginate (10% w/v) and trehalose (20% of polymer). The patches were characterised using optical microscopy, scanning electron microscopy and folding endurance. Serum IgG, TLC, granulocyte count, lymphocyte count and CRP were assessed and results were compared to that of intradermal injections alongside controls. The results showed that polymeric patches had a thickness of 0.8 mm, microneedle projections of 272 ± 12 µm and folding endurance of more than 300. Based on haematological and IgG ELISA assays, microneedle-based BCG administration significantly activated the immune cells and induced production of lymphocytes, granulocytes and peptide-specific IgG in immunised rats that were comparable to injectable counterparts. There was an increase in IgG antibodies from 3 g/L to 5.98 g/L and an increase in leucocytes from 2.6 × 109/L to 18.45 × 109/L. There was also an increase in granulocytes from 14.4% to 29.15% and lymphocyte count from 58.75% to 85.3%. It was concluded that BCG-coated polymeric microneedle patches are suitable for the transdermal delivery of vaccine without inducing discomfort usually observed with injections.


Assuntos
Vacina BCG/química , Vacina BCG/imunologia , Polímeros/química , Administração Cutânea , Animais , Sistemas de Liberação de Medicamentos/métodos , Injeções Intradérmicas , Microinjeções/métodos , Agulhas , Ratos , Adesivo Transdérmico , Vacinação/métodos
3.
Pharmaceutics ; 12(1)2019 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-31861296

RESUMO

The purpose of this study was to apply the Quality by Design (QbD) approach to the electrospinning of fibres loaded with the nonsteroidal anti-inflammatory drugs (NSAIDs) indomethacin (INDO) and diclofenac sodium (DICLO). A Quality Target Product Profile (QTPP) was made, and risk assessments (preliminary hazard analysis) were conducted to identify the impact of material attributes and process parameters on the critical quality attributes (CQAs) of the fibres. A full factorial design of experiments (DoE) of 20 runs was built, which was used to carry out experiments. The following factors were assessed: Drugs, voltage, flow rate, and the distance between the processing needle and collector. Release studies exhibited INDO fibres had greater total release of active drug compared to DICLO fibres. Voltage and distance were found to be the most significant factors of the experiment. Multivariate statistical analytical software helped to build six feasible design spaces and two flexible, universal design spaces for both drugs, at distances of 5 cm and 12.5 cm, along with a flexible control strategy. The current findings and their analysis confirm that QbD is a viable and invaluable tool to enhance product and process understanding of electrospinning for the assurance of high-quality fibres.

4.
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
5.
Pharmaceutics ; 11(8)2019 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-31398833

RESUMO

In the current study, the development of mucoadhesive tablets for buccal delivery of a non-steroidal anti-inflammatory drug was investigated. Binary complexes with piroxicam and cyclodextrins (ß-cyclodextrin (ß-CD), methylated-ß-cyclodextrin (Me-ß-CD), and hydroxypropyl-ß-cyclodextrin (HP-ß-CD)) were prepared by the co-evaporation method. All formulations were characterized by means of differential scanning calorimetry, infrared spectroscopy and powder X-ray diffractometry. Mucoadhesive tablets of binary systems were formulated by direct compression using chitosan as mucoadhesive polymer. The in vitro release profiles of tablets were conducted in simulated saliva and, the drug permeation studies, across porcine buccal mucosa. The results suggest that the rank order effect of cyclodextrins for the drug release was Me-ß-CD > HP-ß-CD > ß-CD, whereas the ex vivo studies showed that the tablets containing chitosan significantly increased the transport of the drug compared to their free complexes. Finally, histological assessment revealed loss of the superficial cell layers, which might be attributed to the presence of cyclodextrins.

6.
Drug Deliv Transl Res ; 8(6): 1815-1827, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-29873037

RESUMO

Electrohydrodynamic atomization (EHDA) is an emerging technique for the production of micron and nano-scaled particles. The process often involves Taylor cone enablement, which results in a fine spray yielding formulated droplets, which then undergo drying during deposition. In this work, novel multi-tip emitter (MTE) devices were designed, engineered and utilized for potential up-scaled EHDA, by comparison with a conventional single-needle system. To demonstrate this, the active ketoprofen (KETO) was formulated using polyvinylpyrrolidone (PVP) polymer as the matrix material. Here, PVP polymer (5% w/v) solution was prepared using ethanol and distilled water (80:20) as the vehicle. KETO was incorporated as 5% w/w of PVP. Physical properties of resulting solutions (viscosity, electrical conductivity, density and surface tension) were obtained. Formulations were electrosprayed through both single and novel MTEs under EHDA conditions at various flow rates (5-300 µl/min) and applied voltages (0-30 kV). The atomization process using MTEs and single nozzle was monitored at using various process parameters via a digital optical camera. Resulting particles were collected 200 mm below processing heads and were analyzed using differential scanning calorimetry (DSC), thermal gravimetric analysis (TGA), X-ray diffraction (XRD) and scanning electron microscopy (SEM). Digital recordings confirmed stable MTE jetting at higher flow rates. Electron micrographs confirmed particle size variation arising due to nozzle head design and evidenced stable jetting derived greater near-uniform particles. DSC, XRD and TGA confirm KETO molecules were encapsulated and dispersed into PVP polymer particles. In conclusion, novel MTE devices enabled stable atomization even at higher flow rates when compared to conventional single-needle device. This indicates an exciting approach for scaling up (EHDA) in contrast to current efforts focusing on multiple-nozzle and pore-based processing outlets.


Assuntos
Composição de Medicamentos/métodos , Cetoprofeno/química , Povidona/química , Varredura Diferencial de Calorimetria , Microscopia Eletrônica de Varredura , Nanopartículas/química , Nebulizadores e Vaporizadores , Tamanho da Partícula , Propriedades de Superfície , Viscosidade
7.
Eur J Pharm Sci ; 102: 147-155, 2017 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-28249823

RESUMO

In this study conventional electrospinning (ESp) was used to prepare a series of buccal films containing indomethacin (INDO, a nonsteroidal anti-inflammatory drug), Ethocel (10), hydroxypropylmethylcellulose (HPMC) and Tween® 80 at various concentrations. The films were characterized using scanning electron microscopy (SEM) and atomic force microscopy (AFM), fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, differential scanning calorimetry (DSC) and X-ray diffraction (XRD). Drug release behaviour was assessed in vitro (buffer pH6.8). SEM revealed film morphology and mean fibre diameter was dependent on the process formulation. INDO was encapsulated in the amorphous state once electrospun as evidenced from DSC and XRD studies. The presence of other excipients within fibrous matrices was confirmed using FTIR and Raman spectroscopy. Loading and release of INDO from filamentous structures was influenced by formulation composition; indicating potential to 'fine-tune' dosage forms. Given that ESp is a one-step preparation method and operational at ambient conditions; an attractive route for engineering tailored film type dosage forms is presented. This is a valuable approach for optimizing dosage forms as needed in a single step for various age groups.


Assuntos
Anti-Inflamatórios não Esteroides/química , Celulose/análogos & derivados , Celulose/química , Sistemas de Liberação de Medicamentos , Indometacina/química , Administração Bucal , Anti-Inflamatórios não Esteroides/administração & dosagem , Varredura Diferencial de Calorimetria , Liberação Controlada de Fármacos , Indometacina/administração & dosagem , Microscopia de Força Atômica , Microscopia Eletrônica de Varredura , Polissorbatos/química , Povidona/química , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman , Tensoativos/química , Tecnologia Farmacêutica , Difração de Raios X
8.
Curr Pharm Des ; 21(22): 3239-47, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26027562

RESUMO

Electrohydrodynamic atomization (EHDA) enabling platform technologies have gathered significant momentum over the last two decades. Utilisation of the underpinning jetting process in tandem with desired materials (including polymers, ceramics, metals and even naturally occurring compounds such as peptides, DNA and cells) provides the basis for novel engineered therapies. Through EHDA processes, the generation of a variety of nano-meter and micro-meter scaled structures with control on surface and encapsulation features is attainable in a single step. While a host of adaptable EHDA techniques have evolved (e.g. printing and template patterning), there are two main processes that continue to dominate: electrospraying (ESy) and electrospinning (ESp). Although ESp has drawn considerable researcher interest for nanofibre applications, ESy is an important and timely process for nano- and micro-particle fabrication. Thus, an appropriate evaluation of ESy is vital. This short review focuses on key developments in the ESy field in relation to nanotechnologies with potential healthcare applications using metals, polymers and ceramics. An insight into the process of particle formation (during EHDA spraying or ESy), process parameters and materials specifications, is provided. Emerging biomedical and other healthcare research through nanotechnologies are highlighted.


Assuntos
Nanotecnologia , Humanos , Metais/química , Nanomedicina/métodos , Nanopartículas/química , Nanotecnologia/métodos , Polímeros/química , Propriedades de Superfície
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