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1.
J Pharm Belg ; (3): 32-41, 2016 Sep.
Artigo em Francês | MEDLINE | ID: mdl-30281242

RESUMO

Aim Aims are: 1] Identify causes of Drug Related Problems (DRPs), interventions performed by pharmacists and results of corticosteroid- related problems and 2] distinguish between problems related to inhaled and general corticosteroids. Methods During 5 days of their internship, 534 final year students of pharmaceutical sciences in six Belgian universities collected DRPs encountered in community pharmacies, as well as related interventions performed by pharmacists and the result of the intervention. The DRPs' electronic registration was done through an adapted tool for Belgium based on the classification of Pharmaceutical Care Network Europe [PCNE- v 6.2]. Findings The frequency of DRPs is 24,8%. 766 DRPs (4,8%) related to corticosteroids, of which 351 were inhaled corticosteroids. The most common causes of corticosteroid-related problems (53- 59%) were technical causes. The most represented category of clinical causes was the inappropriate choice of drug [33-41%]. Pharmacists' intervention was similar for inhaled and general corticosteroids. Pharmacists intervened orally with patients in 38-40% of total interventions, and in writing in 16% of interventions. Pharmacists did not react in 16% of corticosteroid-related problems. 81-83% of PLMS were resolved partially or completely. Conclusion In conclusion, DRPs detected in community pharmacies related to corticosteroid are infrequent (4,8% of DRPs) but 82% of detected problems have been resolved. Furthermore, the study shows the importance for the Belgian health system to introduce an official DRPs classification and software facilitating their documentation in community pharmacies.


Assuntos
Corticosteroides/efeitos adversos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Bélgica/epidemiologia , Feminino , Humanos , Incidência , Masculino , Farmácias
2.
Drug Dev Ind Pharm ; 41(12): 2037-44, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26006329

RESUMO

Chitosan and chitosan derivative-based nanoparticles loaded with insulin were prepared by self-assembly, via electrostatic interactions between the negatively charged drug and the positively charged polymers. In the investigated chitosan derivatives, the amine groups were substituted to different extents (33, 52 or 99%) by 2-hydroxypropyl-3-trimethyl ammonium groups, rendering the polymers permanently positively charged, irrespective of the pH. This is an important property for this type of advanced drug delivery system, since the pH value changes throughout the gastrointestinal tract and electrostatic interactions are of crucial importance for the stability of the nanoparticles. Permanent positive charges are also in favor of mucoadhesion. In contrast, the electric charges of chitosan molecules depend on the pH of the surrounding medium. Since the solubility of the chitosan derivatives increased due to the introduction of quaternary ammonium groups, sodium tripolyphosphate (TPP) was added to the systems to create supplementary cross-links and stabilize the nanoparticles. The presence of TPP influenced both the dissolution of the polymer matrix as well as the resulting release kinetics. The underlying drug release mechanisms were found to be more complex than simple diffusion under constant conditions, likely involving also ionic interactions and matrix dissolution. The most promising formulation was based on a chitosan derivative with 33% substitution degree and characterized by a Z-average of 142 ± 10 nm, a zeta potential of 29 ± 1 mV, an encapsulation efficacy of 52 ± 3% and, most importantly, the release of insulin was sustained for more than 210 min.


Assuntos
Quitosana/química , Portadores de Fármacos/química , Insulina/química , Nanopartículas/química , Administração Oral , Quitosana/administração & dosagem , Quitosana/farmacocinética , Relação Dose-Resposta a Droga , Portadores de Fármacos/administração & dosagem , Portadores de Fármacos/farmacocinética , Avaliação Pré-Clínica de Medicamentos/métodos , Humanos , Insulina/farmacocinética , Nanopartículas/administração & dosagem , Nanopartículas/metabolismo
3.
Int J Pharm ; 597: 120337, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33549812

RESUMO

The main objective of this work was to explore the feasibility to print monoclonal antibody (mAb)-loaded implantable systems using fused-deposition modelling (FDM) to build complex dosage form designs. Indeed, to our knowledge, this work is the first investigation of mAb-loaded devices using FDM. To make this possible, different steps were developed and optimized. A mAb solution was stabilized using trehalose (TRE), sucrose (SUC), hydroxypropyl-ß-cyclodextrin (HP-ß-CD), sorbitol or inulin (INU) in order to be spray dried (SD). Printable filaments were then made of poly(lactide-co-glycolide) (PLGA) and mAb powder (15% w/w) using hot melt extrusion (HME). The FDM process was optimized to print these filaments without altering the mAb stability. TRE was selected and associated to L-leucine (LEU) to increase the mAb stability. The stability was then evaluated considering high and low molecular weight species levels. The mAb-based devices were well-stabilized with the selected excipients during both the HME and the FDM processes. The 3D-printed devices showed sustained-release profiles with a low burst effect. The mAb-binding capacity was preserved up to 70% following the whole fabrication process. These promising results demonstrate that FDM could be used to produce mAb-loaded devices with good stability, affinity and sustained-release profiles of the mAb.


Assuntos
Anticorpos Monoclonais , Tecnologia Farmacêutica , Liberação Controlada de Fármacos , Impressão Tridimensional , Solubilidade , Comprimidos
4.
Biomed Pharmacother ; 139: 111716, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34243618

RESUMO

Despite the advances in targeted therapies and immunotherapy for non-small cell lung cancer (NSCLC) patients, the intravenous administration of carboplatin (CARB) and paclitaxel (PTX) in well-spaced cycles is widely indicated for the treatment of NSCLC from stage II to stage IV. Our strategy was to add a controlled-release cisplatin-based dry-powder for inhalation (CIS-DPI-ET) to the conventional CARB-PTX-IV doublet, administered during the treatment off-cycles to intensify the therapeutic response while avoiding the impairment of pulmonary, renal and haematological tolerance of these combinations. The co-administration of CIS-DPI-ET (0.5 mg/kg) and CARB-PTX-IV (17-10 mg/kg) the same day showed a higher proportion of neutrophils in BALF (35 ± 7% vs 1.3 ± 0.8%), with earlier regenerative anaemia than with CARB-PTX-IV alone. A first strategy of CARB-PTX-IV dose reduction by 25% also induced neutrophil recruitment, but in a lower proportion than with the first combination (20 ± 6% vs 0.3 ± 0.3%) and avoiding regenerative anaemia. A second strategy of delaying CIS-DPI-ET and CARB-PTX-IV administrations by 24 h avoided both the recruitment of neutrophils in BALF and regenerative anaemia. Moreover, all these groups showed higher cytotoxicity (LDH activity, protein content) with no higher renal toxicities. These two strategies seem interesting to be assessed in terms of antitumor efficacy in mice.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Carboplatina/administração & dosagem , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Cisplatino/administração & dosagem , Neoplasias Pulmonares/tratamento farmacológico , Paclitaxel/administração & dosagem , Pós/administração & dosagem , Administração por Inalação , Idoso , Animais , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C
5.
Int J Pharm ; 599: 120425, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33647417

RESUMO

Despite recent advances, platinum-based chemotherapy (partially composed of cisplatin, CIS) remains the backbone of non-small-cell lung cancer treatment. As CIS presents a cumulative and dose-limiting nephrotoxicity, it is currently administered with an interruption phase of 3-4 weeks between treatment cycles. During these periods, the patient recovers from the treatment side effects but so does the tumour. Our strategy is to increase the treatment frequency by delivering a cisplatin controlled-release dry powder for inhalation (CIS-DPI) formulation during these off-cycles to expose the tumour environment for longer to CIS, increasing its effectiveness. This is promising as long as the pulmonary and renal toxicities remain acceptable. The aim of the present investigation was to evaluate the pulmonary and renal tolerance of CIS-DPI (three times per cycle) and CIS using the intravenous (IV) route (CIS-IV) (one time per cycle) as monotherapies and to optimize their combination in terms of dose and schedule. At the maximum tolerated dose (MTD), combining CIS-DPI and CIS-IV impaired the pulmonary and the renal tolerance. Therefore, pulmonary tolerance was improved when the CIS-IV dose was decreased by 25% (to 1.5 mg/kg) while maintaining the MTD for CIS-DPI. In addition to this dose adjustment, a delay of 24 h between CIS-DPI and CIS-IV administrations limited the acute kidney injury.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Animais , Protocolos de Quimioterapia Combinada Antineoplásica , Cisplatino , Humanos , Rim , Neoplasias Pulmonares/tratamento farmacológico , Dose Máxima Tolerável , Camundongos
6.
J Microencapsul ; 27(8): 714-25, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21034364

RESUMO

The aim of this study was to encapsulate ethylhexyl methoxycinnamate (EMC), a commonly used UVB filter, in a solid lipid matrix in order to obtain microparticles and then nanoparticles to reduce its photo-instability under UV light exposure. Glyceryl behenate, rice bran wax and ozokerite were investigated for encapsulating EMC. The suspensions of nanoparticles contained 70% encapsulated EMC (relative to the lipid mass). The absorbance level at 310 nm of suspensions containing nanoparticles was more than twice that of those containing microparticles. So, decreasing the size of particles improved the efficiency of light protection, regardless of the lipid material used. Moreover, free EMC presented a 30% loss of its efficiency after 2 h of irradiation, whereas the three NLC formulations showed a loss of absorbency between 10% and 21%. The in vitro cutaneous penetration test did not show a higher potential penetration for EMC contained in nanosuspensions compared to free EMC.


Assuntos
Cinamatos/química , Lipídeos/química , Nanopartículas/química , Protetores contra Radiação , Raios Ultravioleta , Varredura Diferencial de Calorimetria , Cristalização , Composição de Medicamentos , Emulsões , Ácidos Graxos/química , Humanos , Técnicas In Vitro , Oryza/química , Tamanho da Partícula , Absorção Cutânea , Suspensões , Ceras/química
7.
Int J Cosmet Sci ; 31(4): 279-92, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19496837

RESUMO

The aim of this study was to evaluate the possible penetration through human skin of organic and inorganic filters contained in sunscreen emulsions packaged in aerosol cans, using an in vitro method. Experiments were carried out on two different types of emulsion: W/Si and W/O. This study was conducted using static diffusion cells (Franz cells). The determination of organic UV filters [Methylene Bis Benzotriazolyl Tetramethylbutylphenol (MBBT); Bis-Ethylhexyloxyphenol Methoxyphenyl Triazine (BEMT); Diethylamino Hydroxybenzoyl Hexyl Benzoate (DHHB); Ethylhexyl Methoxycinnamate (EMC); and 2-Ethylhexyl Dimethyl PABA (ED-PABA)] was performed by High Performance Liquid Chromatography (HPLC). Therefore, it was important to develop a single analytical method for the quantification of the five organic filters with the aim of facilitating the experiment. The determination of inorganic filters [titanium dioxide (TiO(2)) and zinc oxide (ZnO)] was performed using an emission spectrometric analysis method (ICP-OES). The HPLC and ICP-OES methods were validated. After a penetration test of 24 h duration, the results showed very low penetration only for two of the organic filters (maximum penetration of 1.21 microg cm(-2) h(-1) for EMC and 0.14 microg cm(-2) h(-1) for MBBT) and no penetration for the inorganic filters. Moreover, more than 50% of each sunscreen agent stayed on the surface on the skin. These results are consistent with those in the literature that presents similar experiments. This study showed that the sprayable sunscreen products developed, which contained high concentrations of UV filters, presented a low level of skin penetration.


Assuntos
Alternativas aos Testes com Animais/métodos , Pele/metabolismo , Protetores Solares/farmacocinética , Cromatografia Líquida de Alta Pressão , Emulsões/farmacocinética , Feminino , Humanos , Técnicas In Vitro , Absorção Cutânea/fisiologia , Raios Ultravioleta
8.
Int J Clin Pharm ; 41(1): 244-250, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30610541

RESUMO

Background Many tools exist to document drug-related problems (DRP), such as the Pharmaceutical Care Network Europe (PCNE) classification. However, none have been adapted and published for French-speaking Belgian community pharmacies. Settings French-speaking Belgian Community pharmacies. Objective The objective was to translate and adapt the PCNE V6.2 classification to the Belgian pharmacy practice and legal setting and to assess the content validity, daily use and inter-rater reliability of this classification. Main Outcome Measure Validation of the French-language adapted PCNE v6.2 classification in Belgium. Method The first step translated and adapted the PCNE V6.2 classification to the Belgian setting. Thereafter academic and community pharmacists evaluated the content validity, which involved six criteria and concerned the instruction manual (clarity, helpfulness) and the registration form (representativeness, logical design, completeness and uniqueness). The next step was the DRP collection, using the PCNE tool daily. Compliance with the instructions and the time needed to solve a DRP were evaluated. Finally, the inter-rater reliability was evaluated by comparing DRP codings done by pharmacist volunteers. Results The classification was translated into French and adapted by adding 16 items. The classification showed a high content validity for the academics and the community pharmacists. A total of 109 DRP forms were coded, with an average resolution time of 5 min. Regarding the inter-rater reliability, 74 tool items out of the set of 83 showed high consistency in coding. Conclusion This study showed that the tool adaptation to a French-speaking Belgian context was reliable and has adequate validity for daily use.


Assuntos
Serviços Comunitários de Farmácia/normas , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/classificação , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Multilinguismo , Assistência Farmacêutica/normas , Tradução , Bélgica/epidemiologia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/prevenção & controle , Humanos , Farmacêuticos/normas , Reprodutibilidade dos Testes
9.
Int J Pharm ; 565: 367-377, 2019 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-31071420

RESUMO

This study assesses the feasibility of printing implantable devices using 3D printing Fused deposition modeling (FDM) technology. The influence of the deposition temperature, the deposition rate and the layer thickness on the printing process and the physical properties of the devices were evaluated. The filaments were composed of neat poly(lactic acid) (PLA) and blends of different plasticizers (polyethylene glycol 400 (PEG 400), triacetine (TA), acetyltriethyl citrate (ATEC) and triethyl citrate (TEC)) at 10% (w/w). The assessment of thermomechanical characteristics and morphology of both filaments and devices (cylinders and dog bones) were performed. The influence of each parameter was evaluated using a design of experiment (DoE) and the significance of the results was discussed. A large amount of data about the evaluation of FDM process parameters are already available in the literature. However, specific insights needed to be increased into the impact of the use of PLA and plasticized PLA raw material on the feasibility of printing devices in three dimensions. To conclude, the ductility was improved with a high layer thickness, low temperature and using ATEC. Whereas, adhesion was promoted with an increase in temperature, a lower layer thickness and adding TA.


Assuntos
Poliésteres/química , Impressão Tridimensional , Tecnologia Farmacêutica , Citratos/química , Plastificantes/química , Polietilenoglicóis/química , Temperatura , Triacetina/química
10.
Eur J Pharm Biopharm ; 68(2): 310-8, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17804212

RESUMO

The aim of this study was to develop a new coated multiple-unit sustained-release floating system that is able to float over an extended period of time. Levodopa was used as a model drug. The system consisted of a 3mm drug-containing gas-generating core, prepared by melt granulation and subsequent compression, and coated with a flexible polymeric membrane. Eudragit RL30D and ATEC were used as a film former and a plasticizer, respectively. The coating level was fixed at 20% (w/w). The floating lag time decreased as the proportion of effervescent agents increased. The optimized coated floating minitablets could float within 20min and remained buoyant for more than 13h. In addition, a sustained release of levodopa for more than 20h was observed.


Assuntos
Resinas Acrílicas/química , Levodopa/administração & dosagem , Comprimidos , Preparações de Ação Retardada , Solubilidade
11.
Int J Pharm ; 364(1): 54-63, 2008 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-18778758

RESUMO

In this study, scintigraphic and pharmacokinetic studies were conducted on 10 healthy, fed volunteers. Two concepts of sustained-release floating minitablets--Levo-Form 1 (matrix) and 2 (coated)--were evaluated and compared to the marketed product Prolopa HBS 125. All the floating forms were radiolabelled with (111)In in order to evaluate their gastric residence time using gamma-scintigraphy. It was shown that the three formulations offered almost the same mean gastric residence time, which was about 240 min. Prolopa HBS 125 and Levo-Form 2 presented intragastric disintegration, which can lead to a more pronounced "peak & valley" effect on the plasma concentration-time profile of levodopa. In contrast, the plasma concentration-time profile of levodopa following the administration of Levo-Form 1 was more evenly distributed. Moreover, Levo-Form 1 provided the lowest variations between men and women in terms of AUC and C(max) values. Finally, when the same amount of inhibitors of extracerebral dopa decarboxylase--carbidopa and benserazide--had been administrated, the mean AUC, C(max) and T(max) values obtained for benserazide were lower than those obtained for carbidopa.


Assuntos
Antiparkinsonianos/administração & dosagem , Antiparkinsonianos/farmacocinética , Carbidopa/administração & dosagem , Carbidopa/farmacocinética , Levodopa/administração & dosagem , Levodopa/farmacocinética , Adulto , Antiparkinsonianos/efeitos adversos , Área Sob a Curva , Carbidopa/efeitos adversos , Química Farmacêutica , Cromatografia Líquida de Alta Pressão , Estudos Cross-Over , Preparações de Ação Retardada , Combinação de Medicamentos , Feminino , Meia-Vida , Humanos , Radioisótopos de Índio , Marcação por Isótopo , Levodopa/efeitos adversos , Masculino , Pós , Cintilografia , Comprimidos , Distribuição Tecidual , Adulto Jovem
12.
Drug Dev Ind Pharm ; 34(8): 827-33, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18618310

RESUMO

This article describes the in vitro evaluation and the enhancement of the floating properties of coated sustained release (SR) minitablets (MTs). The evaluated system consisted of a 3-mm drug-containing gas-generating core prepared by melt granulation and subsequent compression, which was then coated with a flexible polymeric membrane. Eudragit RL30D and acetyl triethylcitrate were used as a film former and a plasticizer, respectively. The coating level was fixed at 20% (wt/wt). The optimally coated floating MTs floated within 10 min and remained buoyant for more than 13 h, regardless of the pH of the test medium. By evaluating the dissolution profiles of levodopa at different pH, it was found that the release of levodopa was sustained for more than 12 h regardless of the pH, even if the coating did not cancel the effect of the pH-dependent solubility of the active drug. Finally, the robustness of the coated floating MTs was assessed by testing the drug release variability in function of the stirring conditions during dissolution tests.


Assuntos
Química Farmacêutica/métodos , Dopaminérgicos/administração & dosagem , Levodopa/administração & dosagem , Ácidos Polimetacrílicos , Preparações de Ação Retardada , Dopaminérgicos/química , Concentração de Íons de Hidrogênio , Levodopa/química , Comprimidos com Revestimento Entérico
13.
Rev Mal Respir ; 35(4): 357-377, 2018 Apr.
Artigo em Francês | MEDLINE | ID: mdl-29731372

RESUMO

Despite severe adverse effects, chemotherapy is still widely used in the treatment of lung tumors, including primary lung tumors and metastases. In order to reduce the risk of harm and to intensify treatment responses, several strategies have been described recently. These include the use of nanomedicine-based chemotherapies and pulmonary drug delivery. However, to treat lung tumors, inhalation cannot be effective and safe without an adaptation of current inhalation techniques, i.e. inhalation devices and drug formulations. This can be very challenging. This review presents recent preclinical developments that could address the limitations observed with aerosolized chemotherapy. The solutions involve the use of dry powder inhalers and advanced drug formulations, such as controlled and sustained release formulations and nanomedicine-based formulations.


Assuntos
Aerossóis , Antineoplásicos/administração & dosagem , Sistemas de Liberação de Medicamentos , Neoplasias Pulmonares/tratamento farmacológico , Administração por Inalação , Aerossóis/administração & dosagem , Aerossóis/efeitos adversos , Antineoplásicos/efeitos adversos , Sistemas de Liberação de Medicamentos/métodos , Sistemas de Liberação de Medicamentos/tendências , Inaladores de Pó Seco/efeitos adversos , Humanos , Neoplasias Pulmonares/metabolismo
14.
Rev Mal Respir ; 35(4): 378-389, 2018 Apr.
Artigo em Francês | MEDLINE | ID: mdl-29731374

RESUMO

Lung tumours have a high incidence and cause many deaths worldwide. Despite progresses in treatment with targeted therapies and immunotherapies, the global 5-year survival rate remains low. In this context, inhaled chemotherapy could provide a means to intensify current therapeutic modalities. This review is based on clinical studies of inhaled chemotherapy against lung tumours. The advantages of this approach in terms of pharmacokinetic ratio and therapeutic index are presented as well as the limitations including contraindications and pulmonary side effects. Moreover, the challenges linked to technical aspects around administration are identified (inhalation device and facilities to limit aerosol propagation and exposure of healthcare professionals). The current developments proposed to overcome these challenges are described briefly. Also discussed are the potential applications for the distribution of the inhaled anticancer drug into tumour-bearing respiratory tracts and finally the potential indications for current therapeutic modalities.


Assuntos
Aerossóis/uso terapêutico , Antineoplásicos/administração & dosagem , Neoplasias Pulmonares/tratamento farmacológico , Padrões de Prática Médica , Administração por Inalação , Aerossóis/normas , Antineoplásicos/efeitos adversos , Humanos , Neoplasias Pulmonares/metabolismo , Nebulizadores e Vaporizadores , Guias de Prática Clínica como Assunto , Padrões de Prática Médica/normas , Padrões de Prática Médica/tendências
15.
Int J Pharm ; 334(1-2): 35-41, 2007 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-17097841

RESUMO

This work relates to the development and the in vitro evaluation of sustained-release minitablets (MT), prepared by melt granulation and subsequent compression, which are designed to float over an extended period of time. Levodopa was used as a model drug. The importance of the composition and manufacturing parameters of the MT on their floating and dissolution properties was then examined. The investigation showed that MT composition and MT diameter had the greatest influence on drug release, which was sustained for more than 8h. By using the same formulation, the best floating properties were obtained with 3mm MT prepared at low compression forces ranging between 50 and 100N. Their resultant-weight (RW) values were always higher than those obtained with a marketed HBS dosage form within 13h. When they were filled into gelatin capsules, no sticking was observed. By evaluating the dissolution profiles of levodopa at different pH values, it was found that dissolution profiles depend more on the prolonged-release ability of Methocel K15M than on the pH-dependent solubility of levodopa. Finally, the robustness of the floating MT was assessed by testing the drug release variability in function of the stirring conditions during dissolution tests.


Assuntos
Antiparkinsonianos/administração & dosagem , Química Farmacêutica , Excipientes/química , Levodopa/administração & dosagem , Metilcelulose/química , Comprimidos/química , Adesividade , Preparações de Ação Retardada/química , Preparações de Ação Retardada/farmacocinética , Composição de Medicamentos , Concentração de Íons de Hidrogênio , Levodopa/química , Solubilidade
16.
Int J Cosmet Sci ; 29(6): 461-71, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18489385

RESUMO

The purpose of this study was to evaluate the possible influence of different formulation and technological parameters such as sunscreen type and concentration, viscosity, propellant gas, actuator and valve type on size and size distribution of droplets in emulsions of waterproof sunscreens conditioned in aerosol cans. Different kinds of emulsion, W/Si and W/O, were prepared with high concentrations of organic and inorganic UV-filters. These formulations were incorporated in aerosol cans with gas (a blend of butane, propane and isobutane). The size and size distribution of the droplets were analysed by laser diffraction using a Malvern Spraytec. The results showed that the sprayability of the formulation and the particle size characteristics of the emitted sprays are dependent on the physicochemical properties of the formulations. Sprayable waterproof sunscreen emulsions, with a high sun protection factor and negligible percentage of emitted droplets below 30 mum, were successfully developed by optimizing formulation parameters and using appropriate actuators and valves.

17.
Eur J Pharm Biopharm ; 64(3): 360-8, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16846725

RESUMO

Ucb-35440-3 is a new drug entity under investigation at UCB S.A. Due to its physicochemical characteristics, the drug, a poorly water-soluble weak base, shows poor solubility and dissolution characteristics. In rat, the low oral bioavailability (F < 10%) is largely due to poor absorption. In order to enhance the solubility and dissolution characteristics, formulation of ucb-35440-3 as nanocrystals has been achieved in this study. Nanoparticles were prepared using high pressure homogenization and were characterized in terms of size and morphology. In vitro dissolution characteristics were investigated and compared to the un-milled drug in order to verify the theoretical hypothesis on the benefit of increased surface area. In vivo pharmacokinetic evaluation of ucb-35440-3 nanoparticles was also carried out on rats. Crystalline state evaluation before and following particle size reduction was conducted through polarized light microscopy and PXRD to denote any possible transformation to an amorphous state during the homogenization process. Drug chemical stability was also assessed following homogenization. The dissolution rate increased significantly at pH 3.0, 5.0 and 6.5 for ucb-35440-3 nanoparticles. However, the pharmacokinetic profile obtained yielded lower systemic exposure than the un-milled compound (in fed state), this although being thought to be the consequence of the drug and formulation characteristics.


Assuntos
Antiasmáticos/farmacocinética , Benzamidas/farmacocinética , Nanopartículas , Piperazinas/farmacocinética , Administração Oral , Animais , Antiasmáticos/administração & dosagem , Antiasmáticos/sangue , Antiasmáticos/química , Benzamidas/administração & dosagem , Benzamidas/sangue , Benzamidas/química , Disponibilidade Biológica , Química Farmacêutica , Cristalização , Estabilidade de Medicamentos , Excipientes/química , Concentração de Íons de Hidrogênio , Derivados da Hipromelose , Masculino , Metilcelulose/análogos & derivados , Metilcelulose/química , Tamanho da Partícula , Piperazinas/administração & dosagem , Piperazinas/sangue , Piperazinas/química , Pressão , Ratos , Ratos Wistar , Solubilidade , Tecnologia Farmacêutica , Fatores de Tempo
18.
Int J Pharm ; 323(1-2): 86-92, 2006 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-16815656

RESUMO

Floating pellets were prepared using the melt pelletization process in a Mi-Pro high shear mixer (Pro-C-epT, Belgium). Formulations were based on a mixture of Compritol and Precirol as meltable binders and on the use of sodium bicarbonate and tartaric acid as gas-generating agents. Good floating abilities were obtained by using the gas-generating agents in both the inner matrix and the outer coating layer of the pellets. In vitro evaluation of floating capability was performed both by using the resultant weight apparatus and by counting floating pellets at the surface of beakers containing 0.1N HCl solution, in vivo evaluation of floating pellets capabilities was also performed. Riboflavin-containing floating pellets (FRF) were administered orally to nine healthy volunteers versus non-floating pellets (NFRF). Volunteers were divided in two groups, fasted group (n=4) 729 kcal and fed group (n=5) 1634 kcal as the total calorie intake on the testing day. An increase of urinary excretion of riboflavin was observed when the volunteers were dosed with the floating pellets, especially after feeding. As riboflavin has a narrow window of absorption in the upper part of small intestine, this phenomenon could be attributable to the gastric retention of floating pellets.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Riboflavina/farmacocinética , Adulto , Algoritmos , Disponibilidade Biológica , Preparações de Ação Retardada/química , Diglicerídeos/química , Composição de Medicamentos/métodos , Jejum/urina , Ácidos Graxos/química , Humanos , Concentração de Íons de Hidrogênio , Masculino , Metilcelulose/química , Pessoa de Meia-Idade , Riboflavina/administração & dosagem , Riboflavina/urina , Bicarbonato de Sódio/química , Tartaratos/química
19.
J Pharm Biomed Anal ; 41(1): 70-6, 2006 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-16303276

RESUMO

The construction and electrochemical response characteristics of two types of poly(vinyl chloride) (PVC) membrane sensors for the determination of amodiaquine hydrochloride (ADQ.2HCl) are described. The sensing membrane comprised an ion-pair formed between the cationic drug and sodium tetraphenyl borate (NaTPB) or potassium tetrakis(4-chlorophenyl) borate (KTCPB) in a plasticized PVC matrix. Eight PVC membrane ion-selective electrodes were fabricated and studied. Several plasticizers were studied namely, dioctyl phthalate (DOP), 2-nitrophenyl octyl ether (NPOE), dioctyl phenylphosphonate (DOPP) and bis(2-ethylhexyl)adipate (EHA). The sensors display a fast, stable and near-Nernstian response over a relative wide ADQ concentration range (3.2 x 10(-6) to 2.0 x 10(-2) M), with slopes comprised between 28.5 and 31.4 mV dec(-1) in a pH range comprised between pH 3.7 and 5.5. The assay of amodiaquine hydrochloride in pharmaceutical dosage forms using one of the proposed sensors gave average recoveries of 104.3 and 99.9 with R.S.D. of 0.3 and 0.6% for tablets (Malaritab) and a reconstituted powder containing ADQ.2HCl, respectively. The sensor was also used for dissolution profile studies of two drug formulations. The sensor proved to have a good selectivity for ADQ.2HCl over some inorganic and organic compounds, however, berberine chloride interfered significantly. The results were validated by comparison with a spectrophotometric assay according to the USP pharmacopoeia.


Assuntos
Amodiaquina/análise , Antimaláricos/análise , Química Farmacêutica/métodos , Cloreto de Polivinila/química , Adipatos/química , Amodiaquina/química , Antimaláricos/química , Antimaláricos/farmacologia , Dietilexilftalato/química , Eletrodos , Éteres/química , Íons , Malária/tratamento farmacológico , Nitrobenzenos/química , Organofosfonatos/química , Preparações Farmacêuticas , Sensibilidade e Especificidade , Comprimidos , Tetrafenilborato/análogos & derivados , Tetrafenilborato/química
20.
Int J Pharm ; 299(1-2): 167-77, 2005 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-15996838

RESUMO

Poorly water-soluble drugs such as nifedipine (NIF) (approximately 20 microg/ml) offer challenging problems in drug formulation as poor solubility is generally associated to poor dissolution characteristics and thus to poor oral bioavailability. In order to enhance these characteristics, preparation of nifedipine nanoparticles has been achieved using high pressure homogenization. The homogenization procedure has first been optimized in regard to particle size and size distribution. Nanoparticles were characterized in terms of size, morphology and redispersion characteristics following water-removal. Saturation solubility and dissolution characteristics were investigated and compared to the un-milled commercial NIF to verify the theoretical hypothesis on the benefit of increased surface area. Crystalline state evaluation before and following particle size reduction was also conducted through differential scanning calorimetry (DSC) and powder X-ray diffraction (PXRD) to denote eventual transformation to amorphous state during the homogenization process. Through this study, it has been shown that initial crystalline state is maintained following particle size reduction and that the dissolution characteristics of nifedipine nanoparticles were significantly increased in regards to the commercial product. The method being simple and easily scaled up, this approach should have a general applicability to many poorly water-soluble drug entities.


Assuntos
Bloqueadores dos Canais de Cálcio/química , Nanoestruturas , Nifedipino/química , Varredura Diferencial de Calorimetria , Química Farmacêutica , Dessecação , Microscopia Eletrônica de Varredura , Tamanho da Partícula , Solubilidade , Fatores de Tempo , Difração de Raios X
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