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1.
Int J Pharm ; 660: 124377, 2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38914351

RESUMO

Lidocaine is generally recognized and preferred for local anaesthesia, but in addition, studies have described additional benefits of lidocaine in cancer therapy, inflammation reduction, and wound healing. These properties contribute to its increasing importance in dermatological applications, and not only in pain relief but also in other potential therapeutic outcomes. Therefore, the purpose of our study was to enhance lidocaine delivery through the skin. A stable nanostructured lipid carrier (NLC), as a passive permeation enhancer, was developed using a 23 full factorial design. The nanosystems were characterized by crystallinity behaviour, particle size, zeta potential, encapsulation efficiency measurements, and one of them was selected for further investigation. Then, NLC gel was formulated for dermal application and compared to a traditional dermal ointment in terms of physicochemical (rheological behaviour) and biopharmaceutical (qualitative Franz diffusion and quantitative Raman investigations) properties. The study also examined the use of 3D printed solid microneedles as active permeation enhancers for these systems, offering a minimally invasive approach to enhance transdermal drug delivery. By actively facilitating drug permeation through the skin, microneedles can complement the passive transport achieved by NLCs, thereby providing an innovative and synergistic approach to improving lidocaine delivery.

2.
Pharmaceutics ; 15(12)2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38140120

RESUMO

Nanotechnology is playing a significant role in modern life with tremendous potential and promising results in almost every domain, especially the pharmaceutical one. The impressive performance of nanomaterials is shaping the future of science and revolutionizing the traditional concepts of industry and research. Titanate nanotubes (TNTs) are one of these novel entities that became an appropriate choice to apply in several platforms due to their remarkable properties such as preparation simplicity, high stability, good biocompatibility, affordability and low toxicity. Surface modification of these nanotubes is also promoting their superior characters and contributing more to the enhancement of their performance. In this research work, an attempt was made to functionalize the surface of titanate nanotubes with carboxylic groups to increase their surface reactivity and widen the possibility of bonding different molecules that could not be bonded directly. Three carboxylic acids were investigated (trichloroacetic acid, citric acid and acrylic acid), and the prepared composites were examined using FT-IR and Raman spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and dynamic light scattering (DLS). The toxicity of these functionalized TNTs was also investigated using adherent cancer cell lines and fibroblasts to determine their safety profile and to draw the basic lines for their intended future application. Based on the experimental results, acrylic acid could be the suitable choice for permanent surface modification with multiple carboxylic groups due to its possibility to be polymerized, thus presenting the opportunity to link additional molecules of interest such as polyethylene glycol (PEG) and/or other molecules at the same time.

3.
Eur J Pharm Sci ; 187: 106491, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37301240

RESUMO

Parkinson's disease (PD) is neurodegenerative chronic illness which affects primarily the elderly over 45 years of age. The symptoms can be various, both non-motor and motor symptoms can appear. The biggest problem in the treatment of the disease is the difficulty in swallowing for the patients. However, buccal patches can solve this problem because the patients do not have to swallow the dosage form, and during application, the API can absorb from the area of the buccal mucosa quickly without causing a foreign body sensation. In our present study, we focused on the development of buccal polymer films with pramipexole dihydrochloride (PR). Films with different compositions were formulated and their mechanical properties and chemical interactions were investigated. The biocompatibility of the film compositions was examined on the TR146 buccal cell line. The permeation of PR was also monitored across the TR146 human cell line. It can be stated that the plasticizer can enhance the thickness and the breaking hardness of the films, while not decreasing their mucoadhesivity significantly. All formulations proved to have cell viability higher than 87%. Finally, we found the best composition (3% SA+1% GLY-PR-Sample1) which can be applied on the buccal mucosa in the treatment of PD.


Assuntos
Doença de Parkinson , Humanos , Idoso , Pramipexol , Doença de Parkinson/tratamento farmacológico , Administração Bucal , Portadores de Fármacos/química , Mucosa Bucal/metabolismo , Sistemas de Liberação de Medicamentos
4.
Biomedicines ; 10(11)2022 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-36428514

RESUMO

The vast scope of 3D printing has ignited the production of tailored medical device (MD) development and catalyzed a paradigm shift in the health-care industry, particularly following the COVID pandemic. This review aims to provide an update on the current progress and emerging opportunities for additive manufacturing following the introduction of the new medical device regulation (MDR) within the EU. The advent of early-phase implementation of the Quality by Design (QbD) quality management framework in MD development is a focal point. The application of a regulatory supported QbD concept will ensure successful MD development, as well as pointing out the current challenges of 3D bioprinting. Utilizing a QbD scientific and risk-management approach ensures the acceleration of MD development in a more targeted way by building in all stakeholders' expectations, namely those of the patients, the biomedical industry, and regulatory bodies.

5.
Biomedicines ; 10(10)2022 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-36289841

RESUMO

In recent years, we have witnessed prominent improvements in urinary catheter coatings to tackle the commonly occurring catheter-associated urinary tract infection (CAUTI) in catheterized patients. CAUTIs are claimed to be one of the most frequent nosocomial infections that can lead to various complications, from catheter encrustation to severe septicaemia and pyelonephritis. Besides general prevention hygienic strategies, antimicrobial-coated urinary catheters show great potential in the prevention of urinary catheter-associated complications. The aim of this review is to present and evaluate recent updates on the development of antimicrobial urinary catheters in the context of the aetiology of urinary malfunction. Subsequently, we shed some light on future perspectives of utilizing 3D printing and the surrounding regulatory directions.

6.
Gels ; 8(9)2022 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-36135271

RESUMO

Poor bioavailability of eye drops is a well-known issue, which can be improved by increasing the residence time on the eye surface and the penetration of the active pharmaceutical ingredient (API). This study aims to formulate in situ gelling mucoadhesive ophthalmic preparations. To increase the residence time, the formulations were based on a thermosensitive polymer (Poloxamer 407 (P407)) and were combined with two types of mucoadhesive polymers. Dexamethasone (DXM) was solubilized by complexation with cyclodextrins (CD). The effect of the composition on the gel structure, mucoadhesion, dissolution, and permeability was investigated with 33 full factorial design. These parameters of the gels were measured by rheological studies, tensile test, dialysis membrane diffusion, and in vitro permeability assay. The dissolution and permeability of the gels were also compared with DXM suspension and CD-DXM solution. The gelation is strongly determined by P407; however, the mucoadhesive polymers also influenced it. Mucoadhesion increased with the polymer concentration. The first phase of drug release was similar to that of the CD-DXM solution, then it became prolonged. The permeability of DXM was significantly improved. The factorial design helped to identify the most important factors, thereby facilitating the formulation of a suitable carrier for the CD-DXM complex.

7.
J Pharm Sci ; 111(10): 2674-2686, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35872025

RESUMO

The term "Medical devices" includes technology-based devices or articles, both basic and complex. Due to these types of variations, a strict, robust, transparent, and sustainable regulatory framework is required. In recent clinical practice, incidents including the breast implant and the hip replacement crisis have made it necessary to improve the regulatory and compliance approaches for the industry to ensure the manufacturing and distribution of safe and innovative MDs within the EU. In response to this, the EU revised the laws governing medical devices and in vitro diagnostics to align with the developments of the sector, address critical safety issues and support innovation. The new regulation (EU) 2017/745 on Medical Devices (MDR) is now applicable from May 26 2021 and the In Vitro Diagnostic Medical Devices Regulation (EU) 2017/746 will take effect from May 2022.In this review, we aim to provide an update on the new Medical Device Regulations in the context of the current medical needs of the world, and also to give a glimpse at the non-EU regulatory landscape. Finally, we take a look at the closed-system transfer devices (CSTD) and COVID facilitated changes promoting demand for continuous improvement and trends in the pharmaceutical and medical industry related areas.


Assuntos
COVID-19 , Legislação de Dispositivos Médicos , COVID-19/epidemiologia , Comércio , Humanos , Preparações Farmacêuticas , Kit de Reagentes para Diagnóstico
8.
Pharmaceutics ; 14(4)2022 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-35456578

RESUMO

Molecular complexation with cyclodextrins (CDs) has long been a known process for modifying the physicochemical properties of problematic active pharmaceutical ingredients with poor water solubility. In current times, the focus has been on the solvent-free co-grinding process, which is an industrially feasible process qualifying as a green technology. In this study, terbinafine hydrochloride (TER), a low solubility antifungal drug was used as a model drug. This study aimed to prepare co-ground products and follow through the preparation process of the co-grinding method in the case of TER and two amorphous CD derivatives: (2-hydroxypropyl)-ß-cyclodextrin (HPBCD); heptakis-(2,6-di-O-methyl)-ß-cyclodextrin (DIMEB). For this evaluation, the following analytical tools and methods were used: phase solubility studies, differential scanning calorimetry (DSC), X-ray powder diffractometry (XRPD), hot-stage X-ray powder diffractometry (HOT-XRPD), Fourier-transform infrared (FT-IR), Raman spectroscopy, and Scanning Electron Microscopy (SEM). Furthermore, in vitro characterization (dissolution and diffusion studies) was performed in two kinds of dissolution medium without enzymes. In the XRPD and SEM studies, it was found that the co-grinding of the components resulted in amorphous products. FT-IR and Raman spectroscopies confirmed the formation of an inclusion complex through the unsaturated aliphatic chain of TER and CDs. In vitro characterization suggested better dissolution properties for both CDs and decreased diffusion at higher pH levels in the case of HPBCD.

9.
Int J Pharm ; 605: 120793, 2021 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-34119582

RESUMO

Counterfeiting of the products for healing is as old as trading, and it is difficult to quantify the magnitude of the problem. It is known that substandard and/or falsified (SF) medicines are a growing global threat to health, and they cause serious social and economic damage. The EU has a strong legal framework for medicines, it is mandatory to meet the requirements of Directive 2011/62/EU. Serialisation prevents SF medicinal products from entering the legal distribution chain. The present study is an extension of the original idea and aims to develop a laser technology-based method to mark an individual traceable code on the surface of the tablet, which technology can also be used for marking personalized medicines. The method is based on the ablation of the upper layer of a double-layer, differently coloured coating. The 2D code should be formed without harming the functional layer, and anyone with a smartphone integrated with a camera should be able to authenticate these drugs with a suitable application. The present findings confirmed that KrF excimer laser and Ti:sapphire femtosecond laser are efficient and reliable for marking. These should be promising candidates for pharmaceutical companies that would like to have additional protection against drug counterfeiters.


Assuntos
Medicamentos Falsificados , Lasers , Comprimidos , Tecnologia
10.
Pharmaceutics ; 13(5)2021 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-33925927

RESUMO

Currently, pharmaceutical companies are working on innovative methods, processes and products. Oral mucoadhesive systems, such as tablets, gels, and polymer films, are among these possible products. Oral mucoadhesive systems possess many advantages, including the possibility to be applied in swallowing problems. The present study focused on formulating buccal mucoadhesive polymer films and investigating the physical and physical-chemical properties of films. Sodium alginate (SA) and hydroxypropyl methylcellulose (HPMC) were used as film-forming agents, glycerol (GLY) was added as a plasticizer, and cetirizine dihydrochloride (CTZ) was used as an active pharmaceutical ingredient (API). The polymer films were prepared at room temperature with the solvent casting method by mixed two-level and three-level factorial designs. The thickness, tensile strength (hardness), mucoadhesivity, surface free energy (SFE), FTIR, and Raman spectra, as well as the dissolution of the prepared films, were investigated. The investigations showed that GLY can reduce the mucoadhesivity of films, and CTZ can increase the tensile strength of films. The distribution of CTZ proved to be homogeneous in the films. The API could dissolve completely from all the films. We can conclude that polymer films with 1% and 3% GLY concentrations are appropriate to be formulated for application on the buccal mucosa as a drug delivery system.

11.
Curr Med Chem ; 28(36): 7461-7476, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33823761

RESUMO

The translation of nanomedicines from the lab level into marketed product faces several challenges, including characterization of physicochemical properties, pharmacodynamics, pharmacokinetics, process control, biocompatibility, and nanotoxicity, scaling-up as well as reproducibility. The challenges of nanomedicine development are in connection with the different requirements from the patient (clinical and therapeutic use), industry (production), and regulatory bodies (authorization process). This paper aims at reviewing the status and regulatory aspects of nano-based drug delivery systems with a focus on the Food and Drug Administration (FDA) and the European Medicine Agency (EMA) regulations. In addition to discussing the risks accompanied by the development of nanomedicine, the potential of following a risk-based methodology from the early stage of the R&D phase is emphasized here to ensure safety and efficacy when developing novel nano-based dosage forms. The R&D of nanomedicines is a complex and multidisciplinary approach, and there are still many challenges in their regulation and legislation. In general, the most critical considerations for nanomedicines are the product quality assessment (physicochemical characteristics, quality control, manufacturing process) and product safety assessment (pharmacokinetics, biodegradation, accumulation, and nanotoxicity). The paper presents a promising paradigm in the development and marketing authorization of nanomedicines, namely the Quality by Design (QbD) approach. Sufficient knowledge on the quality, safety, and efficacy of nanomedicines is necessary to obtain a significant focus on establishing robust, standardized methods for evaluating the critical quality attributes of nanomedicines. The QbD-based submission is highly recommended and required by the regulatory authorities, enabling a smooth clinical translation of the novel nanomedicines.


Assuntos
Nanomedicina , Humanos , Reprodutibilidade dos Testes , Estados Unidos
12.
Int J Pharm ; 570: 118665, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31499234

RESUMO

Substandard and/or falsified medicines are a growing global threat for health and they cause serious social and economic damage. In low- and middle-income countries the failure rate of these medical products is approximately 10.5%. 50% of medicines purchased over the Internet may be fake. According to Directive 2011/62/EU as regards the prevention of falsified medicines from entering into the legal supply chain, a unique identification should be put on each box of drugs in the EU from 9th February 2019. The current project is focusing on the development of a laser technology to mark an individual traceable code on the surface of the tablet. Usually, coatings contain titanium dioxide for sufficient coverage, which makes precision laser coding more difficult. New naturally coloured films do not include those excipients. In this research, we would like to compare the physical-chemical properties of conventionally and naturally coloured coatings after the laser marking procedure by using two types of lasers. This unique identification technology can be used for marking personalized medicine with the doses tailored for each patient, too. To sum up, the present findings may contribute to efficient and reliable laser marking solutions in the unique identification procedure. Based on our measurement results, it can be stated that excimer UV lasers are promising candidates as marking instruments for the polymer film in both conventionally and naturally coloured coatings.


Assuntos
Corantes/química , Medicamentos Falsificados/química , Excipientes/química , Comprimidos/química , Lasers
13.
Int J Pharm ; 562: 11-22, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30877028

RESUMO

In this study, authors adapt the Quality by Design (QbD) concept as well as the Risk Assessment (RA) method to the early development phase of a new nano-sized liposomal formulation for nasal administration with brain target. As a model active agent, a BCS II class drug was chosen to investigate the behaviour of the drugs with lipophilic character. This research presents how to apply this risk-focused approach and concentrates on the first four stages of the QbD implementation. In this way the quality target product profile was defined, the critical factors were identified and an RA was performed. The RA results helped in the factorial design-based liposome preparation by the lipid film hydration method. The prepared liposomes were evaluated (vesicle size, size distribution, and specific surface area). The surface characteristics were also investigated to verify the exactness of the RA and critical factors based theoretical prediction. The results confirm that the QbD approach in liposome development can improve the formulation process. The RA focused predictive approach resulted in a decreased number of studies in practice but in an effective product preparation. Using such innovative design and development models can help to optimise and rationalise the development of liposomes.


Assuntos
Desenho de Fármacos , Lipossomos , Administração Intranasal , Encéfalo/metabolismo
14.
Int J Pharm ; 559: 68-75, 2019 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-30677482

RESUMO

Meloxicam is an anti-inflammatory drug that could be interesting to deliver locally to the lungs to treat inflammation occurring in cystic fibrosis or chronic obstructive pulmonary disease (COPD). Spray drying conditions were optimized to prepare inhalable dry powders, from meloxicam aqueous solution with pH adjustment. A comparison study between non-porous and large porous particles (LPPs) was carried out to demonstrate the relevance of the aimed large size (>5 µm) and low density (<0.2 mg/cm3) formulations. With the appropriate amount of porogen agent, ammonium bicarbonate, LPPs exhibited the same aerodynamic diameter and a higher deposited fraction than smaller but dense particles. The aerodynamic evaluation of LPPs showed that the fine particle fraction (FPF) reached up to 65.8%, while the emitted fraction (EF) reached 85.4%, both higher than for the non-porous particles. Stability tests demonstrated that, after 10 weeks of storage, no significant difference could be detected in the aerodynamic behaviour of the formulations. To the best of our knowledge this is the first time large porous particles, with enhanced aerodynamic properties, from an aqueous solution of meloxicam are reported.


Assuntos
Pulmão/efeitos dos fármacos , Meloxicam/administração & dosagem , Meloxicam/química , Administração por Inalação , Aerossóis/administração & dosagem , Aerossóis/química , Química Farmacêutica/métodos , Portadores de Fármacos/química , Composição de Medicamentos/métodos , Sistemas de Liberação de Medicamentos/métodos , Inaladores de Pó Seco/métodos , Tamanho da Partícula , Porosidade , Pós/administração & dosagem , Pós/química
15.
Drug Des Devel Ther ; 12: 1567-1580, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29910603

RESUMO

PURPOSE: The article reports a wet milling process, where the planetary ball mill was combined with pearl milling technology to reach nanosize range of meloxicam (Mel; 100-500 nm). The main purpose was to increase the dissolution rate and extent of a poorly water-soluble Mel as nonsteroidal anti-inflammatory drug as well as to study its permeability across cultured intestinal epithelial cell layers. METHODS: Viscosity of milled dispersion and particle size distribution and zeta potential of Mel were investigated and differential scanning calorimeter and X-ray powder diffractometer were used to analyse the structure of the suspended Mel. Finally in vitro dissolution test and in vitro cell culture studies were made. RESULTS: It was found that the ratio of predispersion and pearls 1:1 (w/w) resulted in the most effective grinding system (200-fold particle size reduction in one step) with optimized process parameters, 437 rpm and 43 min. Nanosuspension (1% Mel and 0.5% poly[vinyl alcohol]) as an intermediate product showed a stable system with 2 weeks of holding time. This optimized nanosuspension enhanced the penetration of Mel across cultured intestinal epithelial cell layers without toxic effects. CONCLUSION: The dissolution rate of Mel from the poly(vinyl alcohol) stabilized nanosuspension justified its applicability in the design of innovative per oral dosage form (capsule) in order to ensure/give a rapid analgesia.


Assuntos
Álcool de Polivinil/química , Tecnologia Farmacêutica , Tiazinas/química , Tiazóis/química , Células CACO-2 , Sobrevivência Celular/efeitos dos fármacos , Cristalização , Estabilidade de Medicamentos , Humanos , Meloxicam , Nanoestruturas , Tamanho da Partícula , Solubilidade , Análise Espectral Raman , Suspensões , Tiazinas/análise , Tiazinas/farmacologia , Tiazóis/análise , Tiazóis/farmacologia , Viscosidade
16.
Eur J Hosp Pharm ; 25(e2): e139-e143, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31157085

RESUMO

OBJECTIVE: In intensive care units numerous drugs have to be infused simultaneously, resulting inline incompatibility. Propofol is formulated as a lipid emulsion and it is well known that electrolytes can affect the stability of an emulsion system. Our goal was to evaluate and to compare the physical compatibility of three commercial propofol lipid emulsions of different manufacturers, mixing them with the most commonly used crystalloids in intensive care units. METHODS: Simulated Y-site administration was accomplished by mixing the 2% MCT/LCT propofol emulsions with the commonly used crystalloids in the intensive care unit in a 1:1 ratio in a polypropylene syringe. The aliquot samples were evaluated immediately and at 15, 30, 60 and 120 min after preparation by visual observation, pH and droplet size measurement. RESULTS: There was no emulsion breakdown or any visible change during the study period. Mixing the propofols with crystalloids, 10% magnesium sulphate or 10% potassium chloride there was no significant change in the droplet size compared with the original propofol emulsions. A slight alteration in droplet size was noticed in a few of the propofol samples, when magnesium, potassium or both were the secondary additives to the crystalloids, but this is not considered clinically relevant. CONCLUSION: The physical properties of emulsions are determined by component, therefore the compatibility data in literature has to be evaluated prudently. All three commercially available MCT/LCT propofol emulsions are considered physically compatible with the tested crystalloids.

17.
Drug Des Devel Ther ; 11: 2453-2466, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28860716

RESUMO

The nasal delivery of drugs offers a great alternative route to avoid adverse events and to increase patient compliance due to its advantageous properties. Besides nasal application, topical, systemic and central effects are also available. Nasal powders (NPs) have better adhesion due to the additive polymers that may be, eg, gelling or good wettability agents; thus, their bioavailability is better compared to the liquid formulations. Using nanoparticles, innovative and more efficient products can be achieved, which may lead to the improvement of different therapies. The aim of this study was to produce NP formulations containing lamotrigine (LAM) as interactive physical mixtures and nanosized LAM-based formulations. After risk assessment of the preliminary tests, the micrometric properties (particle size and morphology) and the structural properties (differential scanning calorimetry [DSC], X-ray powder diffraction [XRPD]) were investigated; thereafter, physicochemical properties (solubility, polarity) and in vitro dissolution and diffusion profiles were also examined. These product samples showed an appropriate particle size ranging 10-25 µm, while the particle size of LAM in the products was between 120 and 230 nm and the dissolved amount of drug was >60% after 5 minutes in these cases.


Assuntos
Anticonvulsivantes/administração & dosagem , Sistemas de Liberação de Medicamentos , Nanopartículas , Triazinas/administração & dosagem , Administração Intranasal , Varredura Diferencial de Calorimetria , Química Farmacêutica/métodos , Composição de Medicamentos/métodos , Lamotrigina , Tamanho da Partícula , Polímeros/química , Pós , Solubilidade , Triazinas/química , Difração de Raios X
18.
Eur J Pharm Sci ; 95: 54-61, 2016 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-27497612

RESUMO

The focus of this research was to apply the in situ coating technology for producing paracetamol- (PCT-) containing pastilles for paediatric use from a eutectic of two sugar alcohols (sorbitol, xylitol) in one step. This type of melt-technology is more cost-efficient and simpler than other conventional tableting technologies, whereby the formation of the pastilles and their coating occur upon the same fabrication step. We managed to produce pastilles having a softer core and a harder, resistant shell in one cooling step. Adding polyethylene glycol (PEG) 2000 or 6000 to the PCT-containing eutectic, the dissolution rate of PCT could be considerably increased, especially when using PEG 2000, reaching equal dissolution characteristics both under mouth- and gastric-specific conditions. Distributions of the components within the pastilles have been determined by X-ray scattering and Raman spectroscopy. Physico-chemical parameters of the xylitol-sorbitol eutectic and their changes upon adding PCT and PEGs have been determined, and it has been revealed that xylitol and sorbitol form a new entity with a distinguished crystal structure. The significant changes in viscosity were explained and the interaction in the eutectic mixture was investigated using Fourier transform infrared spectroscopy (FT-IR). The uniformity of the physical parameters of the pastilles (including size, weight and drug content) also demonstrates the feasibility of using the cost-efficient and simple one-step eutectic-cooling technology for manufacturing pastilles.


Assuntos
Acetaminofen/síntese química , Álcoois Açúcares/síntese química , Tecnologia Farmacêutica/métodos , Acetaminofen/farmacocinética , Química Farmacêutica , Solubilidade , Álcoois Açúcares/farmacocinética , Comprimidos com Revestimento Entérico , Difração de Raios X/métodos
19.
Eur J Pharm Sci ; 95: 145-151, 2016 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-27496047

RESUMO

The aim of this work was an investigation of the physical changes of the amorphous model material spray-dried trehalose through the use of various analytical techniques and to identify a suitable, rapid method able to quantify the changes. The crystallinity changes and recrystallization process of amorphous samples were investigated by hot-humidity stage X-ray powder diffractometry (HH-XRPD) with fresh samples, conventional X-ray powder diffractometry (XRPD) used stored samples and by differential scanning calorimetry (DSC). The data from the three methods were compared and the various forms of trehalose were analysed. HH-XRPD demonstrated that the recrystallization began at 40 and 60°C up to 45% RH and at 70°C up to 30% RH into dihydrate form. At 70°C up to 60% RH the anhydrous form of trehalose appeared too. Conventional XRPD results showed, that in the 28days stored samples the dihydrate form was detected at 40°C, 50% RH. Storage at 60°C, 40% RH resulted in the appearance of the anhydrous form and at 60°C, 50% RH both polymorphic forms were detected. By carrying out the DSC measurements at different temperatures the fraction of recrystallized trehalose dihydrate was detected. The recrystallization investigated by HH-XRPD and DSC followed Avrami kinetics, the calculated rate constants of isothermal crystallization (K) were same. Both HH-XRPD and conventional XRPD was suitable for the detection of the physical changes of the amorphous model material. DSC measurements showed similar results as HH-XRPD. Primarily HH-XRPD could be suggested for prediction, because the method is fast and every changes could be studied on one sample.


Assuntos
Temperatura Alta , Umidade , Difração de Pó/métodos , Trealose/química , Difração de Raios X/métodos , Cristalização , Trealose/análise
20.
Molecules ; 21(4): 507, 2016 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-27110752

RESUMO

This article reports on the effects of a new combined wet milling technique on the physicochemical properties of meloxicam (MEL). The influence of milling time on the particle size, the crystallinity, the morphology and the dissolution rate of MEL has been studied in the presence and absence of polyvinyl alcohol (PVA) as a stabilizer agent. Micronized MEL particles were produced in aqueous medium which did not contain additive after milling for 10 min. For nanonization an additive and longer milling time were required. After particle size determination the structural and morphological characterization of the wet milled, dried products containing MEL were studied. X-ray powder diffractometry (XRPD) and differential scanning calorimetry (DSC) examinations revealed the change in the crystallinity of MEL. Scanning electron microscopy (SEM) images showed that aggregates of nanosized MEL particles were formed, regardless of the presence of PVA. The nanonized MEL crystals (D50 = 126 nm) exhibited a regular shape and a smooth surface. The increased specific surface area resulted in a high dissolution rate and concentration of free MEL. According to the results, the produced samples could be applied as a basic material (micronized MEL) and intermediate product (micronized and nanonized MEL with PVA) for the design of dosage forms.


Assuntos
Química Farmacêutica/métodos , Tiazinas/química , Tiazóis/química , Varredura Diferencial de Calorimetria , Cristalografia por Raios X , Meloxicam , Tamanho da Partícula , Solubilidade , Propriedades de Superfície
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