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1.
Int J Pharm ; 643: 123264, 2023 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-37488059

RESUMO

The effect of particle size on the sublimation behavior of butylhydroxytoluene (BHT) was investigated when BHT was included as antioxidant in tablets. Sublimation of pure BHT was found to be independent of its particle size, with pore formation on the surface of all tablets after storage at room temperature and above. Moreover, a higher residual BHT content after storage was detected in tablets containing a larger size fraction. X-ray µCT scans revealed the formation of peripherally larger pores at higher BHT particle sizes, implying a slower sublimation rate in the tablet core. A stability study indicated an increase in the extent of BHT sublimation at higher temperature and longer exposure time for all size fractions. The influence of BHT particle size was more pronounced when the tablets were stored at higher temperature, but the effect receded with longer exposure time. Similar trends were seen in film-coated tablets. Due to the short exposure time to elevated temperatures, a gradient in pore size was also observed at smaller particle sizes, with peripheral pores being larger in uncoated tablets. Superficial pores disappeared when a film coating was deposited onto the tablets. After storage of the film-coated tablets, less BHT had sublimated compared to the uncoated tablet. The coating layer did not prevent sublimation, but the process was slowed down.


Assuntos
Antioxidantes , Hidroxitolueno Butilado , Tamanho da Partícula , Comprimidos , Comprimidos com Revestimento Entérico
2.
Eur J Pharm Biopharm ; 188: 217-226, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37207943

RESUMO

The aim of this study was to develop an age-appropriate tablet of mebendazole 500 mg to be used in large donation programs by the World Health Organization (WHO) for preventive chemotherapy of soil-transmitted helminth (STH) infections in pre-school and school-age children living in tropical and subtropical endemic areas. To that end, a new oral tablet formulation was developed that can be either chewed or given to young (≥1 year old) children by spoon after rapid disintegration to a soft mass with the addition of a small amount of water directly on the spoon. Although the tablet was manufactured using conventional fluid bed granulation, screening, blending, and compression processes, one of the main challenges was to combine properties of a chewable, dispersible, and regular (solid) immediate release tablet to meet the predefined requirements. The tablet disintegration time was below 120 s, allowing for administration by the "spoon method". The tablet hardness was higher (160-220 N) than normally applicable for chewable tablets, permitting shipment along a lengthy supply chain in a primary 200-tablet count bottle packaging. In addition, the resulting tablets are stable for 48 months in all climatic zones (I-IV). In this article, several aspects of the development of this unique tablet are described, including formulation, process development, stability, clinical acceptability testing, and regulatory filing.


Assuntos
Helmintíase , Helmintos , Animais , Criança , Pré-Escolar , Humanos , Helmintíase/tratamento farmacológico , Helmintíase/prevenção & controle , Helmintíase/epidemiologia , Mebendazol , Solo , Comprimidos
3.
Drug Dev Ind Pharm ; 43(7): 1126-1133, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28274133

RESUMO

The bioavailability of the anthelminthic flubendazole was remarkably enhanced in comparison with the pure crystalline drug by developing completely amorphous electrospun nanofibres with a matrix consisting of hydroxypropyl-ß-cyclodextrin and polyvinylpyrrolidone. The thus produced formulations can potentially be active against macrofilariae parasites causing tropical diseases, for example, river blindness and elephantiasis, which affect altogether more than a hundred million people worldwide. The bioavailability enhancement was based on the considerably improved dissolution. The release of a dose of 40 mg could be achieved within 15 min. Accordingly, administration of the nanofibrous system ensured an increased plasma concentration profile in rats in contrast to the practically non-absorbable crystalline flubendazole. Furthermore, easy-to-grind fibers could be developed, which enabled compression of easily administrable immediate release tablets.


Assuntos
Mebendazol/análogos & derivados , Nanofibras/química , Povidona/química , Comprimidos/química , beta-Ciclodextrinas/química , 2-Hidroxipropil-beta-Ciclodextrina , Administração Oral , Animais , Disponibilidade Biológica , Química Farmacêutica , Cristalização , Mebendazol/administração & dosagem , Mebendazol/química , Ratos
4.
J Pharm Sci ; 105(9): 2782-2793, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27113473

RESUMO

This study investigates 3 amorphous technologies to improve the dissolution rate and oral bioavailability of flubendazole (FLU). The selected approaches are (1) a standard spray-dried dispersion with hydroxypropylmethylcellulose (HPMC) E5 or polyvinylpyrrolidone-vinyl acetate 64, both with Vitamin E d-α-tocopheryl polyethylene glycol succinate; (2) a modified process spray-dried dispersion (MPSDD) with either HPMC E3 or hydroxypropylmethylcellulose acetate succinate (HPMCAS-M); and (3) confining FLU in ordered mesoporous silica (OMS). The physicochemical stability and in vitro release of optimized formulations were evaluated following 2 weeks of open conditions at 25°C/60% relative humidity (RH) and 40°C/75% RH. All formulations remained amorphous at 25°C/60% RH. Only the MPSDD formulation containing HPMCAS-M and 3/7 (wt./wt.) FLU/OMS did not crystallize following 40°C/75% RH exposure. The OMS and MPSDD formulations contained the lowest and highest amount of hydrolyzed degradant, respectively. All formulations were dosed to rats at 20 mg/kg in suspension. One FLU/OMS formulation was also dosed as a capsule blend. Plasma concentration profiles were determined following a single dose. In vivo findings show that the OMS capsule and suspension resulted in the overall highest area under the curve and Cmax values, respectively. These results cross-evaluate various amorphous formulations and provide a link to enhanced biopharmaceutical performance.


Assuntos
Antinematódeos/administração & dosagem , Antinematódeos/farmacocinética , Mebendazol/análogos & derivados , Animais , Dessecação , Composição de Medicamentos , Sistemas de Liberação de Medicamentos , Umidade , Masculino , Mebendazol/administração & dosagem , Mebendazol/farmacocinética , Metilcelulose/análogos & derivados , Mucosa Bucal/metabolismo , Povidona , Ratos , Ratos Sprague-Dawley , Suspensões , Vitamina E/química
5.
J Opioid Manag ; 10(3): 149-58, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24944065

RESUMO

OBJECTIVE: To evaluate tamper-resistant properties of tapentadol tablets formulated with polyethylene oxide (PEO) matrix. DESIGN: Analytical and physical tests to characterize tablets. INTERVENTIONS: Tapentadol extended release (ER) 50, 100, 150, 200, and 250 mg. MAIN OUTCOME MEASURE(S): Mechanical resistance of tapentadol ER tablets to crushing (all doses), in vitro drug-release profiles of intact and tampered 50- and 250-mg tablets, and resistance to extraction of 250-mg tablets subjected to hammering. RESULTS: Crush resistance testing showed no deformation of tablets with two metal spoons, minimal deformation (no pulverization/breakage) with a pill crusher, slight deformation with a standardized pharmacopeia breaking force tester, and flattening (no pulverization/breakage) with a standardized hammer instrument. Mean in vitro release profiles in quality control medium (0.050 M phosphate buffer, pH 6.8) were similar with intact and tampered (pill crusher) tablets; the release profile was faster for hammered than intact tablets, with 30 percent of the drug released after 30 minutes (slightly higher than maximum release allowed per drug product specifications). Intact tablets were completely resistant to extraction in most organic solvents tested; in aqueous solvents, the amount of drug extracted increased with time. Hammered tablets were less resistant to extraction but required vigorous shaking over extended periods of time to release >50 percent of active ingredient. CONCLUSIONS: In vitro results from tampering attempts presented herein demonstrate that tapentadol ER tablets were resistant to these forms of physical manipulation. Tapentadol ER tablets were also generally resistant to dissolution in most solvents. Developing tamper-resistant formulations is an important step in strategies to mitigate opioid abuse.


Assuntos
Fenóis/química , Química Farmacêutica , Preparações de Ação Retardada , Solubilidade , Comprimidos , Tapentadol
6.
Electrophoresis ; 27(12): 2317-29, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16718715

RESUMO

A CE method for metacycline (MTC) determination was investigated in an inter-laboratory experiment. Many problems were encountered in this study, most of which were related to the transfer of the method to different CE equipment. The reported problems could be classified into different categories: problems related to the precision, to the parameters in the protocol, and to the MTC peak shape. As the peak shape problem was partially responsible for the poor precision, a new CE method was developed in order to obtain a good MTC peak shape on all equipment. The precision of this new method for MTC determination was examined in an intermediate precision study, where the influence of the factors "time" and "equipment" was investigated. Although the new method could be transferred to different instruments, the precision remained poor mainly due to the contributions of the between-replicate and the between-injection variances.


Assuntos
Antibacterianos/análise , Eletroforese Capilar/métodos , Metaciclina/análise , Sensibilidade e Especificidade
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