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1.
AAPS PharmSciTech ; 24(6): 159, 2023 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-37498506

RESUMO

The development of formulations adapted to the patient's age is a challenge in the pharmaceutical industry. Pediatric and geriatric patients may have difficulties in swallowing oral medications when an adequate formulation is not available. Carvedilol is a poorly water-soluble drug used to treat cardiovascular problems; it is commercialized in several countries only as solid oral formulations, which are often manipulated at the point of administration to treat pediatric or geriatric patients. The purpose of this work was to obtain a new dosage form of Carvedilol using safe excipients, suitable for administration to pediatric and geriatric patients. To improve the solubility of Carvedilol, the effect of several factors was analyzed and optimized. Subsequently, to improve the physical stability of the formulations, two preparation methods were analyzed by adding HPMC. In "method 1," HPMC was dissolved in buffer and incorporated into a mixture of Carvedilol-PEG 400, while in "method 2," Carvedilol was solubilized in buffer containing PEG 400, and then, HPMC was added. Finally, microbiological tests were performed to the stable formulations. The factors "pH value" and "concentration of PEG" affected the solubility of Carvedilol. A formulation containing Carvedilol (3 mg/mL), pH=3, PEG 400 (15% v/v), and HPMC (0.25% w/v) prepared by method 2 was stable for 180 days at 4 °C while those containing Carvedilol (5 mg/mL), pH=3, PEG 400 (27% v/v), and HPMC (0.5% w/v), prepared by method 2, were stable for 180 days at 4 and 25°C. These oral liquid formulations were physicochemical and microbiologically stable for 6 months.


Assuntos
Excipientes , Polietilenoglicóis , Humanos , Criança , Idoso , Carvedilol , Solubilidade , Estabilidade de Medicamentos , Administração Oral
2.
Parasitology ; 148(13): 1545-1553, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-35060467

RESUMO

Albendazole (ABZ) is an anthelmintic pharmaceutical commonly used in the treatment of nematode infections. It is a Class II drug poorly water-soluble, with very low bioavailability, a feature particularly limiting to treat the trichinellosis chronic phase. Microcrystals obtained by controlled precipitation using hydroxyethyl cellulose and chitosan have previously been shown to improve ABZ biopharmaceutical properties. This investigation aimed to test the systems' in vivo efficacy in the CBi-IGE murine model of Trichinella spiralis infection in the infection's different phases and parasite' stages. Treatment in the enteral phase led to a 90% decrease in the larval muscle load, probably due to its effect on T. spiralis female fecundity. Both microcrystal systems given in the migratory phase halved muscle load in males, a response not observed in females. The chitosan-based microcrystals proved to be the best when administered in the chronic phase of the infection ­ an increased proportion of L1 dead larvae was found compared to controls, except in CBi+-treated females. Males and females from the highly susceptible CBi+ line presented a significantly different treatment response in this phase. In vivo efficacy depended on the host genotype and sex and was related to the parasite cycle stage in which the formulations were administered.


Assuntos
Anti-Helmínticos , Trichinella spiralis , Triquinelose , Albendazol/farmacologia , Animais , Anti-Helmínticos/farmacologia , Anti-Helmínticos/uso terapêutico , Modelos Animais de Doenças , Feminino , Genótipo , Imunoglobulina E/farmacologia , Imunoglobulina E/uso terapêutico , Masculino , Camundongos , Triquinelose/tratamento farmacológico , Triquinelose/parasitologia
3.
AAPS PharmSciTech ; 21(6): 221, 2020 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-32748291

RESUMO

Sildenafil citrate causes vasodilatation, relaxation of the smooth muscle, and reduction of pulmonary arterial pressure. The latter property makes sildenafil citrate efficient for the treatment of cardiovascular diseases, including pulmonary arterial hypertension. Pediatric patients with pulmonary arterial hypertension are more susceptible to errors in drug administration than adults because of a lack of suitable drug dosages. Thus, the purpose of this study was to develop stable (chemically and microbiologically) sildenafil citrate drop liquid formulation, suitable for pediatric patients (including diabetics), ensuring safety during preparation and storing and improving palatability by using milk as a carrier for administration. The significant factors that affect the sildenafil solubility were evaluated by applying a Plackett-Burman design using two levels with six variables. The experiment showed that the type of buffer and glycerin content influenced the sildenafil solubility. The developed formulations proved to be stable for 6 months at all three assayed conditions (40± 2°C, 75 ± 5% RH; 25± 2°C, 60 ± 5% RH; and 4 ± 2°C). The microbiological tests fit with the requirement of the pharmacopeia at day 0 and 90 and even more at day 180. Finally, the palatability assay showed that 0.82 mL of the formulation containing buffer phosphate, 20% glycerin, and 4 mg mL-1 of sildenafil citrate diluted in 4.8 mL milk (which fits the medium pediatric dose) presented similar palatability to milk alone, and no precipitate or turbidity was observed. Graphical abstract.


Assuntos
Hipertensão Pulmonar/tratamento farmacológico , Citrato de Sildenafila/química , Adulto , Criança , Composição de Medicamentos , Estabilidade de Medicamentos , Humanos , Pessoa de Meia-Idade , Citrato de Sildenafila/uso terapêutico , Solubilidade , Soluções
4.
AAPS PharmSciTech ; 21(3): 112, 2020 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-32236813

RESUMO

This study was aimed to design a simple and novel prototype device for the production of polymeric microparticles. To prove the effectiveness of this device, benznidazole microparticles using chitosan as carrier and NaOH, KOH, or SLS as counter ions were used. For comparison, benznidazole microparticles were prepared by the conventional dripping technique (syringe and gauge) using the same excipients. Microparticles were characterized in terms of encapsulation efficiency, particle shape, size and surface topography, crystallinity characteristics, thermal behavior, and dissolution rate. Then, the pharmacokinetic parameters were evaluated after the oral administration of the microparticles to healthy Wistar rats. The prepared formulations, by means of this device, showed good drug encapsulation efficiency (> 70%). Release studies revealed an increased dissolution of benznidazole from chitosan microparticles prepared using the novel device. It achieved more than 90% in 60 min, while those of the conventional microparticles and raw drug achieved 65% and 68%, respectively, during the same period. Almost spherical benznidazole microparticles with a smooth surface and size around 10-30 µm were observed using scanning electron microscopy. Thermal analysis and X-ray diffraction studies suggested a partial reduction of drug crystallinity. Moreover, the relative oral bioavailability of the novel benznidazole microparticles showed that the area under the curve for the microencapsulated drug was 10.3 times higher than the raw drug. Thus, these findings indicate that the designed glass prototype device is a useful alternative to formulate benznidazole polymeric microparticles with improved biopharmaceutical properties and could be useful for other therapeutic microparticulate systems.


Assuntos
Composição de Medicamentos/instrumentação , Nitroimidazóis/química , Animais , Quitosana/química , Liberação Controlada de Fármacos , Nitroimidazóis/farmacocinética , Ratos , Ratos Wistar
5.
AAPS PharmSciTech ; 21(5): 149, 2020 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-32435903

RESUMO

Albendazole (ABZ), an anthelmintic compound widely used in the treatment of systemic nematode infections, is included in the list of class II drugs based on the Biopharmaceutical Classification System. ABZ has limited effectiveness due to its poor water solubility and consequent low bioavailability. Bioavailability of novel ABZ microcrystals based on hydroxyethylcellulose (S4A) or chitosan (S10A) was studied in male and female mice of two inbred lines, from the murine CBi-IGE model of trichinellosis, differing in susceptibility to this parasitosis (line CBi/L, resistant; line CBi+, susceptible). ABZ microcrystals were administered orally, and albendazole sulfoxide (ABZSO) was quantified in plasma by high-performance liquid chromatography. Mice given the microcrystals showed a significant increase in maximum plasmatic concentration (Cmax) compared with those receiving pure ABZ (P < 0.01). In both genotypes, males and females given S4A had higher Cmax than those receiving S10A (P < 0.05). CBi/L showed a greater Cmax than CBi+ (significantly different only in females treated with S4A (P = 0.001)). CBi/L females attained a higher Cmax than males (P < 0.05). No sex effect was observed for this variable in CBi+ (P > 0.05). The results of the pharmacokinetic analysis indicate that the microcrystalline formulations optimize ABZ bioavailability, both in males and females, S4A being the best system in CBi/L mice and S10A in CBi+. In summary, the microcrystals increased ABZ bioavailability, and under the conditions of this investigation, both host genotype and sex influenced the pharmacokinetic parameters measured.


Assuntos
Albendazol/farmacocinética , Celulose/análogos & derivados , Quitosana/química , Albendazol/química , Animais , Área Sob a Curva , Disponibilidade Biológica , Celulose/química , Feminino , Genótipo , Masculino , Camundongos , Caracteres Sexuais
6.
Int J Mol Sci ; 20(15)2019 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-31357647

RESUMO

Among different Candida species triggering vaginal candidiasis, Candida albicans is the most predominant yeast. It is commonly treated using azole drugs such as Tioconazole (TIO) and Econazole (ECO). However, their low water solubility may affect their therapeutic efficiency. Therefore, the aim of this research was to produce a novel chitosan nanocapsule based delivery system comprising of TIO or ECO and to study their suitability in vaginal application. These systems were characterized by their physicochemical properties, encapsulation efficiency, in vitro release, storage stability, cytotoxicity, and in vitro biological activity. Both nanocapsules loaded with TIO (average hydrodynamic size of 146.8 ± 0.8 nm, zeta potential of +24.7 ± 1.1 mV) or ECO (average hydrodynamic size of 127.1 ± 1.5 nm, zeta potential of +33.0 ± 1.0 mV) showed excellent association efficiency (99% for TIO and 87% for ECO). The analysis of size, polydispersity index, and zeta potential of the systems at 4, 25, and 37 °C (over a period of two months) showed the stability of the systems. Finally, the developed nanosystems presented fungicidal activity against C. albicans at non-toxic concentrations (studied on model human skin cells). The results obtained from this study are the first step in the development of a pharmaceutical dosage form suitable for the treatment of vaginal candidiasis.


Assuntos
Antifúngicos/administração & dosagem , Quitosana/química , Portadores de Fármacos/química , Nanopartículas/química , Antifúngicos/química , Candida albicans/efeitos dos fármacos , Fenômenos Químicos , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Estabilidade de Medicamentos , Econazol/administração & dosagem , Econazol/química , Imidazóis/administração & dosagem , Imidazóis/química , Testes de Sensibilidade Microbiana , Estrutura Molecular , Nanocápsulas/química , Nanopartículas/ultraestrutura
7.
AAPS PharmSciTech ; 21(1): 16, 2019 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-31807963

RESUMO

Triclabendazole belongs to the class II/IV of the Biopharmaceuticals Classification System, and its low aqueous solubility represents a major drawback during the development of effective dosage forms. Therefore, the goal of this study was to elucidate whether polymeric solid dispersions would represent a suitable approach to overcome such disadvantage. Due to the lack of information on triclabendazole release, four different dissolution media were evaluated to analyze drug dissolution rate. The polymeric solid dispersions were characterized by X-ray diffraction and Fourier transform infrared spectroscopy. The selected final formulations were further stored for 24 months, and their physical stability was evaluated by means of X-ray diffraction and drug dissolution assays. Drug solubility studies indicated that poloxamer 407 (P407) solubilized a higher amount of drug than polyethylene glycol 6000. Drug-to-carrier ratio, nature of the selected carriers, and the type of dissolution media were important factors for increasing dissolution. By infrared spectroscopy, there were no specific interactions between the drug and polymers. The physicochemical characterization of the systems showed a detectable evidence of drug amorphization by increasing the carrier ratio. Micromeritic studies indicated that raw triclabendazole, physical mixtures, and reference formulation showed poor flow properties, in contrast to the triclabendazole:P407 solid dispersion sample. Both the crystalline properties and dissolution rate of selected samples were very similar after 24 months at room temperature. Thus, considering physical stability and dissolution studies, the development of the solid dispersion is a very suitable methodology to improve triclabendazole dissolution and, potentially, its biopharmaceutical performance.


Assuntos
Antiplatelmínticos/química , Sistemas de Liberação de Medicamentos/métodos , Triclabendazol/química , Administração Oral , Antiplatelmínticos/administração & dosagem , Varredura Diferencial de Calorimetria/métodos , Química Farmacêutica/métodos , Cristalização/métodos , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Solubilidade , Espectrofotometria Infravermelho/métodos , Triclabendazol/administração & dosagem , Difração de Raios X/métodos
8.
AAPS PharmSciTech ; 19(4): 1781-1788, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29603083

RESUMO

Liquid formulations can be used in children of different ages by varying the volume of the administered dose in order to ensure an exact dosage. The aim of this work was to develop and to optimize a safe liquid atenolol formulation and to carry out the corresponding chemical and microbiological stability studies. A Plackett-Burman design was used to determine the factors that could be critical in the development of the formulations, and a central composite design was used to determine the optimal working conditions. As a result of these analyses, three formulations were selected and their stability studied in three storage conditions, 4, 25, and 40°C. After 6 months of stability testing, the optimal systems showed no pH change or atenolol loss; however, only glycerin-based formulations showed no microbial development. These systems, employing excipients in a range that the EMA has recommended, showed chemical and microbiological stability for at least 6 months even at the worst storage conditions.


Assuntos
Atenolol/síntese química , Excipientes/síntese química , Administração Oral , Antiarrítmicos/administração & dosagem , Antiarrítmicos/síntese química , Atenolol/administração & dosagem , Criança , Composição de Medicamentos , Estabilidade de Medicamentos , Excipientes/administração & dosagem , Humanos , Soluções Farmacêuticas/administração & dosagem , Soluções Farmacêuticas/síntese química
9.
AAPS PharmSciTech ; 19(3): 1152-1159, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29218582

RESUMO

Albendazole (ABZ) and ricobendazole (RBZ) are referred to as class II compounds in the Biopharmaceutical Classification System. These drugs exhibit poor solubility, which profoundly affects their oral bioavailability. Micellar systems are excellent pharmaceutical tools to enhance solubilization and absorption of poorly soluble compounds. Polysorbate 80 (P80), poloxamer 407 (P407), sodium cholate (Na-C), and sodium deoxycholate (Na-DC) have been selected as surfactants to study the solubilization process of these drugs. Fluorescence emission was applied in order to obtain surfactant/fluorophore (S/F) ratio, critical micellar concentration, protection efficiency of micelles, and thermodynamic parameters. Systems were characterized by their size and zeta potential. A blue shift from 350 to 345 nm was observed when ABZ was included in P80, Na-DC, and Na-C micelles, while RBZ showed a slight change in the fluorescence band. P80 showed a significant solubilization capacity: S/F values were 688 for ABZ at pH 4 and 656 for RBZ at pH 6. Additionally, P80 micellar systems presented the smallest size (10 nm) and their size was not affected by pH change. S/F ratio for bile salts was tenfold higher than for the other surfactants. Quenching plots were linear and their constant values (2.17/M for ABZ and 2.29/M for RBZ) decreased with the addition of the surfactants, indicating a protective effect of the micelles. Na-DC showed better protective efficacy for ABZ and RBZ than the other surfactants (constant values 0.54 and 1.57/M, respectively), showing the drug inclusion into the micelles. Entropic parameters were negative in agreement with micelle formation.


Assuntos
Albendazol/análogos & derivados , Albendazol/química , Ácido Desoxicólico/química , Fluorescência , Micelas , Poloxâmero/química , Polissorbatos/química , Colato de Sódio/química , Solubilidade , Espectrometria de Fluorescência , Tensoativos/química , Termodinâmica
10.
AAPS PharmSciTech ; 19(8): 3907, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29744815

RESUMO

In the INTRODUCTION section, Atenolol is defined in parenthesis as (ATN, Fig. 1.) The correct definition is (ATN). Fig 1 corresponds to the RESULTS section.

11.
AAPS PharmSciTech ; 19(5): 2311-2321, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29845501

RESUMO

Triclabendazole is the first-line drug of choice to treat and control fasciolasis, a neglected parasitic human disease. It is a class II/IV compound according to the Biopharmaceutics Classification System. Thus, the aim of this study was to improve aqueous solubility and dissolution rate of triclabendazole complexed with 2-hydroxylpropyl-ß-cyclodextrin (HP-ß-CD) and methyl-ß-cyclodextrin (Me-ß-CD) at 1:1 and 1:2 M ratio. The impact of storage on the solubility, dissolution profile, and solid-state properties of such complexes was also investigated. Drug-carrier interactions were characterized by infrared spectroscopy, differential scanning calorimetry, X-ray diffractometry, and scanning electron microscopy. The solubility of triclabendazole improved up to 256- and 341-fold using HP-ß-CD and Me-ß-CD, respectively. In particular, the drug complexed with Me-ß-CD showed a positive deviation from linearity, suggesting that its solubility increases with an increasing concentration of Me-ß-CD concentration in a nonlinear manner. The drug dissolution was found to be improved through complex formation with HP-ß-CD and Me-ß-CD. In particular, the 1:2 M ratio complexes exhibited higher dissolution than the corresponding 1:1 M ratio complexes. The physicochemical characterization of the systems showed strong evidence of amorphous phases and/or of the formation of an inclusion complex. Stored at 25 °C, 60% RH for 24 months, drug complexed with ß-cyclodextrins (CDs) at 1:2 M ratio remained amorphous. Based on these findings, it is postulated that the formation of triclabendazole-CD inclusion complexes produced significant enhancement in both the dissolution and solid-state properties of the drug, which may lead to the development of triclabendazole novel formulations with improved biopharmaceutical characteristics.


Assuntos
Anti-Helmínticos/química , Benzimidazóis/química , Ciclodextrinas/química , Sistemas de Liberação de Medicamentos/métodos , Anti-Helmínticos/administração & dosagem , Anti-Helmínticos/metabolismo , Benzimidazóis/administração & dosagem , Benzimidazóis/metabolismo , Varredura Diferencial de Calorimetria , Ciclodextrinas/administração & dosagem , Ciclodextrinas/metabolismo , Microscopia Eletrônica de Varredura , Solubilidade , Espectrofotometria Infravermelho , Espectroscopia de Infravermelho com Transformada de Fourier , Triclabendazol , Difração de Raios X
12.
AAPS PharmSciTech ; 19(3): 1274-1286, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29313262

RESUMO

Praziquantel (PZQ) is the recommended, effective, and safe treatment against all forms of schistosomiasis. Solid dispersions (SDs) in water-soluble polymers have been reported to increase solubility and bioavailability of poorly water-soluble drugs like PZQ, generally due to the amorphous form stabilization. In this work, poloxamer (PLX) 237 and poly(vinylpyrrolidone) (PVP) K30 were evaluated as potential carriers to revert PZQ crystallization. Binary and ternary SDs were prepared by the solvent evaporation method. PZQ solubility increased similarly with PLX either as binary physical mixtures or SDs. Such unpredicted data correlated well with crystalline PZQ and PLX as detected by solid-state NMR (ssNMR) and differential scanning calorimetry in those samples. Ternary PVP/PLX/PZQ SDs showed both ssNMR broad and narrow superimposed signals, thus revealing the presence of amorphous and crystalline PZQ, respectively, and exhibited the highest PZQ dissolution efficiency (up to 82% at 180 min). SDs with PVP provided a promising way to enhance solubility and dissolution rate of PZQ since PLX alone did not prevent recrystallization of amorphous PZQ. Based on ssNMR data, novel evidences on PLX structure and molecular dynamics were also obtained. As shown for the first time using ssNMR, propylene glycol and ethylene glycol constitute the PLX amorphous and crystalline components, respectively.


Assuntos
Anti-Helmínticos/química , Portadores de Fármacos/química , Poloxâmero/química , Povidona/química , Praziquantel/química , Anti-Helmínticos/administração & dosagem , Varredura Diferencial de Calorimetria , Cristalização , Praziquantel/administração & dosagem , Solubilidade
13.
AAPS PharmSciTech ; 19(8): 3734-3741, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30255471

RESUMO

Drug repositioning refers to the identification of new therapeutic indications for drugs already approved. Albendazole and ricobendazole have been used as anti-parasitic drugs for many years; their therapeutic action is based on the inhibition of microtubule formation. Therefore, the study of their properties as antitumor compounds and the design of an appropriate formulation for cancer therapy is an interesting issue to investigate. The selected compounds are poorly soluble in water, and consequently, they have low and erratic bioavailability. In order to improve their biopharmaceutics properties, several formulations employing cyclodextrin inclusion complexes were developed. To carefully evaluate the in vitro and in vivo antitumor activity of these drugs and their complexes, several studies were performed on a breast cancer cell line (4T1) and BALB/c mice. In vitro studies showed that albendazole presented improved antitumor activity compared with ricobendazole. Furthermore, albendazole:citrate-ß-cyclodextrin complex decreased significantly 4T1 cell growth both in in vitro and in vivo experiments. Thus, new formulations for anti-parasitic drugs could help to reposition them for new therapeutic indications, offering safer and more effective treatments by using a well-known drug.


Assuntos
Antiparasitários/administração & dosagem , Ciclodextrinas/administração & dosagem , Reposicionamento de Medicamentos/métodos , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Albendazol/administração & dosagem , Albendazol/análogos & derivados , Albendazol/química , Animais , Antiparasitários/química , Disponibilidade Biológica , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/fisiologia , Ciclodextrinas/química , Feminino , Humanos , Células MCF-7 , Camundongos , Camundongos Endogâmicos BALB C , Distribuição Aleatória , Resultado do Tratamento , Neoplasias de Mama Triplo Negativas/patologia , Difração de Raios X , beta-Ciclodextrinas/administração & dosagem , beta-Ciclodextrinas/química
14.
Trop Med Int Health ; 22(12): 1514-1522, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28944986

RESUMO

OBJECTIVES: To develop an alcohol-free solution suitable for children of benznidazole, the drug of choice for treatment of Chagas disease. METHODS: In a quality-by-design approach, a systematic optimisation procedure was carried out to estimate the values of the factors leading to the maximum drug concentration. The formulations were analysed in terms of chemical and physical stability and drug content. The final preparation was subjected to an in vivo palatability assay. Mice were infected and treated orally in a murine model. RESULTS: The results showed that benznidazole solubility increased up to 18.38 mg/ml in the optimised co-solvent system. The final formulation remained stable at all three temperatures tested, with suitable drug content and no significant variability. Palatability of the preparation was improved by taste masking of BZL. In vivo studies showed that both parasitaemia and mortality diminished, particularly at a dose of 40 mg/kg/day. CONCLUSION: Quality by design was a suitable approach to formulate a co-solvent system of benznidazole. The in vivo studies confirmed the suitability of the optimised such solutions to diminish both parasitaemia and mortality. Thus, this novel alternative should be taken into account for further clinical evaluation in all age ranges.


Assuntos
Doença de Chagas/parasitologia , Formas de Dosagem , Nitroimidazóis/administração & dosagem , Solventes , Tripanossomicidas/administração & dosagem , Trypanosoma cruzi , Álcoois , Animais , Doença de Chagas/tratamento farmacológico , Doença de Chagas/mortalidade , Química Farmacêutica , Criança , Chlorocebus aethiops , Contraindicações , Humanos , Camundongos Endogâmicos BALB C , Parasitemia/tratamento farmacológico , Parasitemia/parasitologia , Polietilenoglicóis , Propilenoglicol , Solubilidade , Trypanosoma cruzi/efeitos dos fármacos , Trypanosoma cruzi/crescimento & desenvolvimento , Células Vero , Água
15.
AAPS PharmSciTech ; 18(4): 947-956, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-27882479

RESUMO

The oral route has notable advantages to administering dosage forms. One of the most important questions to solve is the poor solubility of most drugs which produces low bioavailability and delivery problems, a major challenge for the pharmaceutical industry. Albendazole is a benzimidazole carbamate extensively used in oral chemotherapy against intestinal parasites, due to its extended spectrum activity and low cost. Nevertheless, the main disadvantage is the poor bioavailability due to its very low solubility in water. The main objective of this study was to prepare microcrystal formulations by the bottom-up technology to increase albendazole dissolution rate, in order to enhance its antiparasitic activity. Thus, 20 novel microstructures based on chitosan, cellulose derivatives, and poloxamer as a surfactant were produced and characterized by their physicochemical properties and in vitro biological activity. To determine the significance of type and concentration of polymer, and presence or absence of surfactant in the crystals, the variables area under the curve, albendazole microcrystal solubility, and drug released (%) at 30 min were analyzed with a three-way ANOVA. This analysis indicated that the microcrystals made with hydroxyethylcellulose or chitosan appear to be the best options to optimize oral absorption of the active pharmaceutical ingredient. The in vitro evaluation of anthelmintic activity on adult forms of Trichinella spiralis identified system S10A as the most effective, of choice for testing therapeutic efficacy in vivo.


Assuntos
Albendazol , Trichinella spiralis/efeitos dos fármacos , Triquinelose/tratamento farmacológico , Administração Oral , Albendazol/administração & dosagem , Albendazol/farmacocinética , Animais , Anti-Helmínticos/administração & dosagem , Anti-Helmínticos/farmacocinética , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Disponibilidade Biológica , Celulose/análogos & derivados , Celulose/química , Celulose/farmacologia , Quitosana/química , Quitosana/farmacologia , Sistemas de Liberação de Medicamentos , Solubilidade
16.
AAPS PharmSciTech ; 18(4): 936-946, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28108973

RESUMO

In this work, chitosan films were prepared by a casting/solvent evaporation methodology using pectin or hydroxypropylmethyl cellulose to form polymeric matrices. Miconazole nitrate, as a model drug, was loaded into such formulations. These polymeric films were characterized in terms of mechanical properties, adhesiveness, and swelling as well as drug release. Besides, the morphology of raw materials and films was investigated by scanning electron microscopy; interactions between polymers were analyzed by infrared spectroscopy and drug crystallinity studied by differential scanning calorimetry and X-ray diffraction. In addition, antifungal activity against cultures of the five most important fungal opportunistic pathogens belonging to Candida genus was investigated. Chitosan:hydroxypropylmethyl cellulose films were found to be the most appropriate formulations in terms of folding endurance, mechanical properties, and adhesiveness. Also, an improvement in the dissolution rate of miconazole nitrate from the films up to 90% compared to the non-loaded drug was observed. The in vitro antifungal activity showed a significant activity of the model drug when it is loaded into chitosan films. These findings suggest that chitosan-based films are a promising approach to deliver miconazole nitrate for the treatment of candidiasis.


Assuntos
Candidíase Bucal/tratamento farmacológico , Quitosana , Sistemas de Liberação de Medicamentos , Derivados da Hipromelose/farmacologia , Miconazol , Adesividade , Administração Bucal , Antidiarreicos/química , Antidiarreicos/farmacologia , Antifúngicos/química , Antifúngicos/farmacologia , Quitosana/química , Quitosana/farmacologia , Composição de Medicamentos , Humanos , Miconazol/química , Miconazol/farmacologia , Microscopia Eletrônica de Varredura/métodos , Pectinas/química , Pectinas/farmacologia , Polímeros/farmacologia , Difração de Raios X/métodos
17.
Bioorg Med Chem Lett ; 26(2): 602-608, 2016 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-26642766

RESUMO

An efficient and green method has been developed for the synthesis of succinyl-ß-cyclodextrin in aqueous media obtaining very good yield. Acidic groups have been introduced in the synthesized carrier molecule to improve the guest-host affinity. To evaluate the suitability of the novel excipient focused to develop oral dosage forms, albendazole, a BSC class II compound, was chosen as a model drug. The ß-cyclodextrin derivative and the inclusion complex were thoroughly characterized in solution and solid state by phase solubility studies, FT-IR spectroscopy, SEM, XRD, ESI-MS, DSC, 1D (1)H NMR, 1D (13)C NMR, selective 1D TOCSY, 2D COSY, 2D HSQC, 2D HMBC and ROESY NMR spectroscopy. Phase solubility studies indicated that both of them ß-cyclodextrin and succinyl-ß-cyclodextrin formed 1:1 inclusion complexes with albendazole, and the stability constants were 68M(-1) (ß-cyclodextrin), 437M(-1) (succinyl-ß-cyclodextrin), respectively. Water solubility and dissolution rate of albendazole were significantly improved in complex forms. Thus, the succinyl-ß-cyclodextrin derivative could be a promising excipient to design oral dosage forms.


Assuntos
Albendazol/administração & dosagem , Anti-Helmínticos/administração & dosagem , Portadores de Fármacos/química , Ácido Succínico/química , beta-Ciclodextrinas/química , Albendazol/química , Anti-Helmínticos/química , Varredura Diferencial de Calorimetria , Portadores de Fármacos/síntese química , Química Verde , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Solubilidade , Espectrometria de Massas por Ionização por Electrospray , Ácido Succínico/síntese química , Difração de Raios X , beta-Ciclodextrinas/síntese química
18.
Drug Dev Ind Pharm ; 41(2): 244-52, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24237328

RESUMO

Both an experimental design and optimization techniques were carried out for the development of chitosan-pectin-carboxymethylcellulose microspheres to improve the oral absorption of albendazole as a model drug. The effect of three different factors (chitosan, pectin and carboxy methyl cellulose concentrations) was studied on five responses: yield, morphology, dissolution rate at 30 and 60 min, and encapsulation efficiency of the microspheres. During the screening phase, the factors were evaluated in order to identify those which exert a significant effect. Simultaneous multiple response optimizations were then used to find out experimental conditions where the system shows the most adequate results. The optimal conditions were found to be: chitosan concentration, 1.00% w/v, pectin concentration 0.10% w/v and carboxymethylcellulose concentration 0.20% w/v. The bioavailability of the loaded drug in the optimized microspheres was evaluated in Wistar rats which showed an area under curve (AUC) almost 10 times higher than the pure drug.


Assuntos
Albendazol/administração & dosagem , Albendazol/farmacocinética , Administração Oral , Animais , Área Sob a Curva , Disponibilidade Biológica , Carboximetilcelulose Sódica/administração & dosagem , Química Farmacêutica/métodos , Quitosana/administração & dosagem , Sistemas de Liberação de Medicamentos , Estabilidade de Medicamentos , Técnicas In Vitro , Masculino , Microscopia Eletrônica de Varredura , Microesferas , Pectinas/administração & dosagem , Ratos , Ratos Wistar
19.
Drug Dev Ind Pharm ; 40(11): 1476-82, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23971494

RESUMO

Encapsulation of albendazole, a class II compound, into polymeric microparticles based on chitosan-sodium lauryl sulfate was investigated as a strategy to improve drug dissolution and oral bioavailability. The microparticles were prepared by spray drying technique and further characterized by means of X-ray powder diffractometry, infrared spectroscopy and scanning electron microscopy. The formation of a novel polymeric structure between chitosan and sodium lauryl sulfate, after the internal or external gelation process, was observed by infrared spectroscopy. The efficiency of encapsulation was found to be between 60 and 85% depending on the internal or external gelation process. Almost spherically spray dried microparticles were observed using scanning electron microscopy. In vitro dissolution results indicated that the microparticles prepared by internal gelation released 8% of the drug within 30 min, while the microparticles prepared by external gelation released 67% within 30 min. It was observed that the AUC and Cmax values of ABZ from microparticles were greatly improved, in comparison with the non-encapsulated drug. In conclusion, the release properties and oral bioavailability of albendazole were greatly improved by using spraydried chitosan-sodium lauryl sulphate microparticles.


Assuntos
Albendazol/química , Anti-Helmínticos/química , Quitosana/química , Dodecilsulfato de Sódio/química , Albendazol/farmacocinética , Animais , Anti-Helmínticos/farmacocinética , Disponibilidade Biológica , Liberação Controlada de Fármacos , Masculino , Microscopia Eletrônica de Varredura , Tamanho da Partícula , Difração de Pó , Ratos , Ratos Wistar , Espectroscopia de Infravermelho com Transformada de Fourier , Tecnologia Farmacêutica
20.
AAPS PharmSciTech ; 14(1): 64-73, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23225117

RESUMO

The objective of the present paper was the development and the full characterization of antifungal films. Econazole nitrate (ECN) was loaded in a polymeric matrix formed by chitosan (CH) and carbopol 971NF (CB). Polyethylene glycol 400 and sorbitol were used as plasticizing agents. The mechanical properties of films were poorer when the drug was loaded, probably because crystals of ENC produces network outages and therefore reduces the polymeric interactions between the polymers. Polymers-ECN and CH-CB interactions were analyzed by Fourier-transform infrared spectroscopy (FTIR), thermal gravimetry analysis, and differential thermal analysis (DTA-TGA). ECN did not show structure alterations when loaded into the films. In scanning electron microphotographs and atomic force microscopy analysis, films prepared with CB showed an evident wrinkle pattern probably due to the strong interactions between the polymers, which were observed by FTIR and DTA-TGA. The in vitro activity of the formulations against Candida krusei and Candida parapsilosis was twice as greater as the commercial cream, probably as a result of the antifungal combination of the drug with the CH activity. All these results suggest that these polymeric films containing ECN are potential candidates in view of alternatives dosages forms for the treatment of the yeast assayed.


Assuntos
Antifúngicos/farmacologia , Polímeros/farmacologia , Desenho de Fármacos , Avaliação Pré-Clínica de Medicamentos , Técnicas In Vitro , Microscopia de Força Atômica , Microscopia Eletrônica de Varredura , Espectroscopia de Infravermelho com Transformada de Fourier , Termogravimetria
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