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1.
Int J Pharm Compd ; 24(1): 77-82, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32023219

RESUMO

This study reports on the stability of United States Pharmacopeia-grade metronidazole powder and commercially available metronidazole tablets in two dye-free oral suspending vehicles, namely Oral Mix and Oral Mix Sugar-Free. Metronidazole at 50 mg/mL was prepared individually in Oral Mix and Oral Mix Sugar-Free suspension vehicles and placed in 50-mL amber polyethyleneterephthalate bottles and 3-mL amber plastic syringes and stored at 4°C or 25°C/60% relative humidity for 90 days. The solutions were analyzed at the time of preparation and at 7 days, 14 days, 30 days, 45 days, 60 days, 75 days, and 90 days, with the concentration of metronidazole measured by high-performance liquid chromatography with photodiode array detection. The oral solutions were also monitored for pH, homogeneity, color, and odor. Except for the Oral Mix suspension of metronidazole prepared from the United States Pharmacopeia-grade powder and from the commercial tablet, when stored in pre-filled syringes, all the other preparations were stable at 4°C or 25°C/60% relative humidity for 90 days, with the metronidazole remaining within ± 10% of the initial concentration. The pH, color, odor, and resuspendability remained essentially unchanged. Metronidazole in Oral Mix and Oral Mix Sugar-Free oral suspensions, compounded from United States Pharmacopeia-grade powder or commercially available tablets, are a suitable alternative as an extemporaneously prepared medication.


Assuntos
Metronidazol , Administração Oral , Cromatografia Líquida de Alta Pressão , Composição de Medicamentos/métodos , Estabilidade de Medicamentos , Suspensões , Comprimidos/administração & dosagem , Estados Unidos
2.
AAPS PharmSciTech ; 21(2): 62, 2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-31925586

RESUMO

The study mainly aimed to improve the solubility of honokiol (HK) by preparing honokiol nanosuspensions (HNS). In this study, HNS were obtained using Kolliphor®P407 (P407) as a stabilizer through melting method combined with high pressure homogenization (HPH). The crystalline state of HNS was confirmed through differential scanning calorimetry (DSC) and X-ray Diffraction (XRD). In vitro, the dissolution rate of HNS was significantly improved than that of pure HK. In vivo, higher anti-inflammatory activity was achieved after free HK had been made into HNS. There was no significant difference between the degree of edema (DE) of HNS group and that of aspirin group. Consequently, melting method combined with HPH was a potent technique to prepare HNS. Furthermore, nanosuspension was a valid formulation that could be utilized to enhance the anti-inflammatory effect of HK.


Assuntos
Anti-Inflamatórios/farmacologia , Compostos de Bifenilo/farmacologia , Lignanas/farmacologia , Animais , Compostos de Bifenilo/química , Feminino , Lignanas/química , Masculino , Camundongos , Nanopartículas/química , Solubilidade , Suspensões
3.
J Environ Manage ; 255: 109939, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31790872

RESUMO

Conventional flocculants bear environmental and health concerns which could be avoided by applying natural materials, particularly polysaccharide and glycoprotein-containing ones. In the present study, yeast cell wall (YCW), a natural polymer matrix, was used as natural flocculant. To prepare YCW, Saccharomyces cerevisiae was cultivated in bench scale fermenter. After characterization, YCW was employed as anionic flocculant in jar tests to remove turbidity from kaolin suspensions at different conditions where either alum or poly aluminum chloride (PAC) was coagulant. Generally, the lower coagulant consumption, higher turbidity removal or faster sedimentation was observed by using YCW as flocculant. The developed flocculant was more effective in the presence of PAC compared to alum. At best, by applying 300 mg/L YCW, the highest turbidity removals of 98 and 97% were achieved using 10 ppm PAC at pH 6.5 and 50 ppm alum at pH 7.5, respectively. The presence of the flocculant in the structure of the flocs was proved by FTIR analysis. The final pH of the treated suspensions was suitable for discharge purpose without the need for neutralization. The excess positive charge neutralization and bridging were the governing mechanism in coagulation-flocculation process. YCW with proper performance, GRAS designation and readily availability can be considered as natural alternative to chemical anionic flocculants where the process needs safe compounds.


Assuntos
Caulim , Purificação da Água , Ânions , Floculação , Polímeros , Suspensões
4.
Environ Technol ; 41(3): 287-295, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29974822

RESUMO

In this study, the flocculation properties of FucoPol, a bacterial extracellular polysaccharide, were investigated. FucoPol is a high molecular weight polymer and negatively charged due to the presence of glucuronic acid and the acyl groups succinyl and pyruvyl. High flocculation rate values (>70%) were achieved with a low bioflocculant dosage of 1 mg/L, for pH values in the range 3-5 and temperature within 15-20°C. The bioflocculant was also shown to be stable after freezing/thawing and heating up to 100°C. Given the polymer's anionic character, the size of flocs formed and their surface profile, bridging seems to be the main flocculation mechanism of FucoPol. This study demonstrated that FucoPol is a promising natural, biodegradable and biocompatible alternative to the currently used synthetic or inorganic hazardous products, with potential to be used as a novel flocculation agent in several applications, such as water treatment, food or mining. Further studies will involve evaluating the reduction of cation dosage on flocculation efficiency, as well as testing the applicability of FucoPol to flocculate different types of suspended solids, such as, for example, activated carbons, soil solids or yeast cells.


Assuntos
Caulim , Purificação da Água , Floculação , Concentração de Íons de Hidrogênio , Polissacarídeos Bacterianos , Suspensões
5.
Chemosphere ; 239: 124736, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31494326

RESUMO

In this work, a novel process involving the preparation of nanochitosan-grafted flocculants (CPAM-g-NCS) to treat low turbid and salmonella suspensions simultaneously was introduced. Nanotechnology was employed to enhance the adsorption-adhesion and sterilization abilities of dual-functional flocculants. The monomers of chitosan, acrylamide, methacryloyl ethyl trimethyl ammonium chloride, and sodium tripolyphosphate were utilized for flocculants copolymerization. Then, using fourier-transform infrared spectroscopy, nuclear magnetic resonance hydrogen spectrum, and thermogravimetric and differential scanning calorimetry analysis, the successful synthesis of CPAM-g-NCS was verified. Scanning electron microscopy and size analysis suggested that nanostructured flocculants with irregular morphology and nanocolloids of 60.44 nm were formed. CPAM-g-NCS was applied to treat a series of simulated low turbid and salmonella suspensions. The simulation results showed that the minimum residual turbidity of 1.97 NTU and optical density of 0.16 (initial 0.89) can be achieved at dosages of 2.5 and 8.75 mg L-1, respectively, which were superior to conventional organics flocculants. Mechanistic studies suggested that the excellent adsorption property, and large numbers of quaternary ammonium and amino groups of nanoflocculants contributed to the superior flocculation and antibacterial performance of CPAM-g-NCS.


Assuntos
Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Nanoestruturas/química , Purificação da Água/métodos , Acrilamida/química , Varredura Diferencial de Calorimetria , Quitosana/química , Floculação , Espectroscopia de Ressonância Magnética , Metacrilatos/química , Microscopia Eletrônica de Varredura , Polimerização , Salmonella typhimurium/efeitos dos fármacos , Espectroscopia de Infravermelho com Transformada de Fourier , Suspensões , Termogravimetria , Microbiologia da Água
6.
J Oncol Pharm Pract ; 25(8): 1907-1915, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31694495

RESUMO

PURPOSE: Use of aprepitant for chemotherapy-induced nausea and vomiting prophylaxis in patients unable to swallow capsules is hindered by the lack of a commercially available oral liquid formulation in many jurisdictions. A stable oral suspension can be extemporaneously prepared using commercially available capsules. We aimed to determine the bioavailability of this aprepitant suspension relative to the capsule. METHODS: This two-period crossover study enrolled 17 healthy adult volunteers. Volunteers received a single 125 mg aprepitant dose during each study period. Order of formulation presentation (capsule vs suspension first) was randomized. Thirteen blood samples were collected over a 48-h period. Aprepitant plasma concentrations were determined using liquid chromatography-mass spectroscopy. Relative bioavailability was defined as the geometric least squares mean ratio for area under the concentration versus time curve (AUC) from time zero to infinity of the aprepitant suspension versus the capsule. Bioequivalence, defined as per Health Canada guidelines, was assessed as a secondary aim. RESULTS: Relative bioavailability of the aprepitant suspension was 82.3% (90% CI: 69.09-98.00%). Bioequivalence was not established: geometric least squares mean ratios (suspension/capsule) for AUC time zero to 48 h and maximum concentration were 87.8% (90% CI: 75.48-102.16%) and 86.1% (90% CI: 75.59-98.16%), respectively. No serious adverse events were observed. CONCLUSIONS: With a relative bioavailability of 82.3%, the extemporaneous aprepitant oral suspension was well-absorbed relative to the capsule. Though not bioequivalent to the oral capsule, the clinical use of this aprepitant oral suspension in adult and pediatric patients unable to swallow capsules is likely to be effective and safe.


Assuntos
Aprepitanto/administração & dosagem , Administração Oral , Adulto , Aprepitanto/farmacocinética , Área Sob a Curva , Disponibilidade Biológica , Canadá , Cápsulas , Estudos Cross-Over , Feminino , Humanos , Masculino , Estudos Prospectivos , Suspensões , Equivalência Terapêutica , Adulto Jovem
7.
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi ; 31(5): 535-537, 2019 Oct 16.
Artigo em Chinês | MEDLINE | ID: mdl-31713388

RESUMO

OBJECTIVE: To compare the effectiveness of snail control between immersion of molluscicides through tide diversion and mollusciciding by spraying in marshland areas. METHODS: Immersion of 26% suspension concentrate of metaldehyde and niclosamide through tide diversion and spraying 26% suspension concentrate of metaldehyde and niclosamide alone were employed for snail control in two neighboring snail-breeding marshlands, and snails were surveyed before and after mollusciciding. The mortality of snails and the density of living snails were estimated. RESULTS: The density of living snails reduced by 72.19% and 100.00% 1 and 2 years after immersion of 26% suspension concentrate of metaldehyde and niclosamide through tide diversion, and 5.93% and 18.15% 1 and 2 years after spraying 26% suspension concentrate of metaldehyde and niclosamide alone. CONCLUSIONS: Immersion of 26% suspension concentrate of metaldehyde and niclosamide through tide diversion is significantly superior to spraying 26% suspension concentrate of metaldehyde and niclosamide along for snail control, and implementation of immersion of 26% suspension concentrate of metaldehyde and niclosamide through tide diversion for more than 2 successive years may achieve a higher snail control efficiency.


Assuntos
Moluscocidas , Niclosamida , Controle de Pragas , Caramujos , Animais , Imersão , Controle de Pragas/métodos , Inquéritos e Questionários , Suspensões , Ondas de Maré , Áreas Alagadas
8.
Int J Pharm Compd ; 23(6): 519-527, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31751949

RESUMO

Amlodipine besylate is an antihypertensive agent recommended for the management of hypertension in children and adolescents. The commercially available 2.5-mg, 5-mg, and 10-mg amlodipine besylate tablets do not provide the necessary flexibility in dosing needed for treating children. This flexibility is readily achieved using an oral, liquid dosage form. However, no commercial liquid dosage form of amlodipine currently exists. An extemporaneously compounded suspension from pure drug powder or commercial tablets would provide a convenient option to meet unique patient needs. The purpose of this study was to determine the physicochemical stability of extemporaneously compounded amlodipine besylate suspensions in the PCCA Base, SuspendIt. This base is a sugar-free, paraben-free, dye-free, and gluten-free thixotropic vehicle containing a natural sweetener obtained from the monk fruit. The study design included two amlodipine besylate concentrations to provide stability documentation over a bracketed concentration range for eventual use by compounding pharmacists. A robust stabilityindicating high-performance liquid chromatographic assay for the determination of the chemical stability of amlodipine besylate in SuspendIt was developed and validated. Suspensions of amlodipine were prepared in SuspendIt at 0.5-mg/mL and 10.0-mg/mL concentrations, selected to represent a range within which the drug is commonly dosed. Samples were stored in plastic amber prescription bottles at two temperature conditions (5°C and 25°C). Samples were assayed initially, and at the following time points: 7 days, 14 days, 29 days, 46 days, 60 days, 90 days, 120 days, and 180 days. Physical data such as pH, viscosity, and appearance were also noted. All measurements were obtained in triplicate. A stable extemporaneous product is defined as one that retains at least 90% of the initial drug concentration throughout the sampling period. This study demonstrates that amlodipine besylate is physically and chemically stable in SuspendIt for 90 days in the refrigerator and 7 days at room temperature, retaining 90% of the label claim (initial drug concentration) at both concentrations. The pH values did not change significantly. The viscosity of the refrigerated samples at both concentrations decreased slightly, while that of the room temperature samples showed a marked increase in viscosity. This study provides a viable, compounded alternative for amlodipine in a liquid dosage form, with an adequate beyond-use-date to meet patient needs. The study further provides stability documentation over a bracketed amlodipine concentration range of 0.5 mg/mL to 10.0 mg/mL, allowing compounding pharmacists more flexibility in customizing their formulations.


Assuntos
Anlodipino , Anti-Hipertensivos , Cromonas , Composição de Medicamentos , Administração Oral , Adolescente , Anlodipino/química , Anti-Hipertensivos/química , Criança , Cromatografia Líquida de Alta Pressão , Estabilidade de Medicamentos , Armazenamento de Medicamentos , Humanos , Suspensões
9.
Drug Deliv ; 26(1): 1092-1103, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31735092

RESUMO

Drug nanosuspensions/nanocrystals have been recognized as one useful and successful approach for drug delivery. Drug nanocrystals could be further decorated to possess extended functions (such as controlled release) and designed for special in vivo applications (such as drug tracking), which make best use of the advantages of drug nanocrystals. A lot of novel and advanced size reduction methods have been invented recently for special drug deliveries. In addition, some novel downstream processes have been combined with nanosuspensions, which have highly broadened its application areas (such as targeting) besides traditional routes. A large number of recent research publication regarding as nanocrystals focuses on above mentioned aspects, which have widely attracted attention. This review will focus on the recent development of nanocrystals and give an overview of regarding modification of nanocrystal by some new approaches for tailor-made drug delivery.


Assuntos
Nanopartículas/química , Preparações Farmacêuticas/química , Animais , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos/métodos , Humanos , Suspensões/química
10.
Int J Nanomedicine ; 14: 7447-7460, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31686816

RESUMO

Objective: This study aimed to investigate the interaction between the ion-complementary self-assembling peptide RADA16-I and the hydrophobic drug mangiferin (MA), and the potential of the self-assembling peptide to be exploited as a drug carrier of MA. Methods: The RADA16-I-MA suspension was prepared by magnetic stirring, followed by fluorescence spectrophotometry, particle size determination, rheological properties analysis, and in vitro release assay to characterize the interaction between RADA16-I and MA. Then, the effects of in situ MA-loaded hydrogel on the proliferation of KYSE 30 and DLD-1 tumor cells and the toxic effect of the hydrogel on 293T renal epithelial cells were studied by the Cell Counting Kit 8 method. Results: The RADA16-I-MA suspension was formed in water under magnetic stirring; the in situ hydrogel was formed when the suspension was added to PBS. The particle size in the RADA16-I-MA suspension was around 300-600 nm with an average size of 492 nm. Within 24 h, the cumulative release of MA from the RADA16-I-MA hydrogel was about 80%. The release rate of MA from the hydrogel was dependent on the concentration of RADA16-I and the release can be fitted with a first-order kinetic equation. The results suggested that the self-assembling peptide can stabilize MA in water to form a relatively stable suspension; the results also indicated that controlled release of MA from the RADA16-I-MA in situ hydrogel formed from the RADA16-I-MA suspension can be achieved by adjusting the concentration of the peptide in suspension. The cell viability studies showed that the RADA16-I-MA in situ hydrogel not only can maintain or enhance the intrinsic proliferation inhibition effects of MA on tumor cells, but also can reduce the toxicity of MA to normal cells. Conclusion: The self-assembling peptide RADA16-I can be a potential candidate for constructing a delivery system of the hydrophobic drug MA.


Assuntos
Liberação Controlada de Fármacos , Hidrogéis/química , Peptídeos/química , Xantonas/química , Morte Celular , Linhagem Celular , Proliferação de Células , Sobrevivência Celular/efeitos dos fármacos , Coloides/química , Elasticidade , Humanos , Tamanho da Partícula , Reologia , Espectrometria de Fluorescência , Suspensões , Viscosidade
11.
AAPS PharmSciTech ; 20(8): 326, 2019 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-31659558

RESUMO

Present study was aimed to increase the oral bioavailability and reduce the fast fed variability of Ibrutinib by developing nanosuspension by simple precipitation-ultrasonication method. A three factor, three level, box-behnken design was used for formulation optimization using pluronic F-127 as stabilizer. Size and polydispersity index of the developed formulations were in the range of 278.6 to 453.2 nm and 0.055 to 0.198, respectively. Field emission scanning electron microscope (FESEM) revealed discrete units of nanoparticles. Further, differential scanning calorimetry (DSC) and powder X-ray diffraction (PXRD) studies confirmed the transformation of crystal drug to amorphous. The amorphous nature was retained after 6-month storage at room temperature. Size reduction to nano range and polymorphic transformation (crystalline to amorphous) increased the solubility of nanosuspension (21.44-fold higher as compared to plain drug). In vivo studies of plain drug suspension displayed a significant pharmacokinetic variation between fasting and fed conditions. The formulation had shown increased Cmax (3.21- and 3.53-fold), AUC0-t (5.21- and 5.83-fold) in fasting and fed states compared to that of values obtained for plain drug in fasting state (Cmax 48.59 ± 3.30 ng/mL and AUC0-t 137.20 ± 35.47 ng.h/mL). Significant difference was not observed in the pharmacokinetics of nanosuspension in fasting and fed states. The formulation had improved solubility in the intestinal pH, which might be the driving force behind the decreased precipitation and increased absorption at intestinal region. Optimistic results demonstrated nanosuspension as a promising approach for increasing the solubility, extent of absorption and diminishing the fast fed variability.


Assuntos
Desenho de Drogas , Nanopartículas/química , Nanopartículas/metabolismo , Pirazóis/síntese química , Pirazóis/metabolismo , Pirimidinas/síntese química , Pirimidinas/metabolismo , Administração Oral , Animais , Disponibilidade Biológica , Varredura Diferencial de Calorimetria , Masculino , Nanopartículas/administração & dosagem , Tamanho da Partícula , Poloxâmero/química , Pirazóis/administração & dosagem , Pirimidinas/administração & dosagem , Ratos , Ratos Wistar , Solubilidade , Suspensões , Difração de Raios X/métodos
12.
Clin Nephrol ; 92(6): 312-318, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31661062

RESUMO

BACKGROUND: Rapid and accurate microbiological detection is crucial for effective treatment of peritonitis patients with peritoneal dialysis (PD). Although centrifugation of dialysis effluents can increase the pathogen culture-positive rate, a lack of both centrifugation facilities and experienced staff has prevented its widespread implementation, particularly in basic-level hospitals in developing countries. Thus, we developed a simple peritoneal sediment-collecting method, suspension precipitation method, for microbiological diagnosis of peritonitis. MATERIALS AND METHODS: In the suspension precipitation method, drained effluent bags from individual patients were hung for 1 hour to allow the suspension to drip to the bottom layer of the bag for sediment collection. Sediments obtained by centrifugation from the same batch of dialysis effluent were used as positive controls. Both sediment sample types were then cultured in blood-culture bottles. Subsequent analysis of the pathogen-positive detection rate and species comparison between the two methods were undertaken. RESULTS: Among 90 PD patients, the pathogen positive-detection rate between methods was comparable, as demonstrated by 75 (83.33%) with the suspension precipitation method and 77 (85.56%) by the centrifugation method. Their positive pathogen species were also similar, and the concordance rate was 97.78%. CONCLUSION: The suspension precipitation method is a simple, convenient, and reliable peritoneal sediment-collecting method that is suitable for a wide array of uses, particularly in basic-level hospitals without centrifugation technology.


Assuntos
Técnicas Microbiológicas/métodos , Diálise Peritoneal/efeitos adversos , Peritonite/diagnóstico , Precipitação Química , Humanos , Estudos Prospectivos , Suspensões
13.
J Photochem Photobiol B ; 199: 111625, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31610430

RESUMO

The cultivated grapevine V. vinifera is a rich source of stilbene compounds such as resveratrol, which are widely believed to provide dietary protection against the development of cardiovascular disease and some forms of cancer. Elicitation is a well-known strategy to increase commercial production of natural products in plant cell suspension culture systems. Callus tissues obtained from berry slices of V. vinifera cv. Shahani grown on an optimized medium were used to develop cell suspension cultures used to study the effects of elicitation on stilbene synthesis. The effect of two light regimes (135.1 µmol. s-1 m-2 radiation, and dark), the concentration of phenylalanine (Phe; 0, 0.1, 0.5 and 1 mM) and of methyl jasmonate elicitor (MeJA; 0 and 25 µM), alone or in combination, were tested. The results showed that cultures grown in darkness resulted in significantly higher levels of the accumulation of total stilbenes (resveratrol + piceid) compared with the high light condition. The combined treatments of dark +1 mM Phe and dark +25 µM MeJA induced the synthesis of high levels of total phenolics, total flavonoids and total stilbenes. Finally, the combined elicitation of dark +1 mM Phe + 25 µM MeJA gave the highest synergistic coefficient (1.24) and proved to be the most effective treatment for the production of total phenolics, total flavonoids, and total stilbenes with mean contents of 384.80 mg GA/g DW, 527.62 mg catechin/g DW and 188.34 µg/g DW, respectively. The results of our study suggest that the combinations of dark together with MeJA and/or Phe can be used as an efficient method for the future scale-up of V. vinifera cell cultures for the production of high value stilbene compounds in a bioreactor system.


Assuntos
Acetatos/metabolismo , Técnicas de Cultura de Células/métodos , Ciclopentanos/metabolismo , Oxilipinas/metabolismo , Fenilalanina/metabolismo , Metabolismo Secundário/efeitos dos fármacos , Vitis/citologia , Vias Biossintéticas , Catequina/metabolismo , Linhagem Celular , Condutividade Elétrica , Flavonoides/metabolismo , Glucosídeos/metabolismo , Concentração de Íons de Hidrogênio , Luz , Fenóis/metabolismo , Resveratrol/metabolismo , Estilbenos/metabolismo , Suspensões/metabolismo
14.
Artif Cells Nanomed Biotechnol ; 47(1): 3961-3975, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31588802

RESUMO

Ion-complementary self-assembling peptides have potential in delivering hydrophobic drugs. This study involved two self-assembling peptides, RADA16-I and RVDV16-I, of which RVDV16-I was a novel self-assembling peptide with different hydrophobic side chains designed from RADA16-I. The purpose of this study was to observe the interaction between different self-assembling peptides and emodin through fluorescence spectrophotometry, CD, SEM and AFM; to construct a preliminary suspension in-situ hydrogel delivery system for emodin with the self-assembling peptides; and to investigate the drug-loading and drug-releasing properties of the self-assembling peptides on emodin. The results showed that both peptides can interact with emodin and the interaction was dominated by hydrophobic interaction. The aqueous solutions of both self-assembling peptides can form relatively stable suspensions with emodin under mechanical stirring, and the suspension can form in-situ hydrogel under physiological condition. In vitro release of emodin from the hydrogels showed a manner of sustained release to some extent. Cell viability studies showed inherent proliferation inhibiting effects of emodin on tumor cells was maintained or enhanced through the in-situ hydrogels. The self-assembling peptides RADA16-I and RVDV16-I had showed promising drug-loading and drug-releasing performance for hydrophobic drugs. It is reasonable to exploit self-assembling peptides as drug carriers for their great potential to improve delivery of hydrophobic drugs.


Assuntos
Antineoplásicos/química , Preparações de Ação Retardada/química , Emodina/química , Hidrogéis/química , Peptídeos/química , Células A549 , Antineoplásicos/administração & dosagem , Antineoplásicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Preparações de Ação Retardada/administração & dosagem , Preparações de Ação Retardada/farmacologia , Portadores de Fármacos/química , Portadores de Fármacos/farmacologia , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Emodina/administração & dosagem , Emodina/farmacologia , Células Hep G2 , Humanos , Hidrogéis/farmacologia , Interações Hidrofóbicas e Hidrofílicas , Estrutura Molecular , Suspensões
15.
Drug Des Devel Ther ; 13: 3249-3258, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31571827

RESUMO

Background: Electronic tongue (ET) is a well-established technology that is used to detect the taste of a food or a medicinal product and to differentiate between different products based on their tastes. In addition, it can be used to monitor environmental parameters and biochemical and biological processes. Purpose: This study aims to assess any correlation between the results of pharmacopeial quality control (ie, assay, impurities, and dissolution, etc) and ET analysis for reconstituted cefdinir (CR) suspension over 10 days (ie, shelf-life). Methods: The reconstituted CR suspension was tested for several quality attributes such as dissolution behavior, pH, assay, related substances, and microbial contamination. An HPLC analytical method was verified and then used for chemical analysis. The taste of CR reconstituted suspension was followed over 10 days and was then compared with the quality control results. Moreover, Pearson's correlation test was used to find a correlation between chemical analysis results and ET results. Results: Pearson's test of correlation showed a significant correlation (p-value <0.05) between the conventional chemical analysis results (% of CR, % of preservative, % of released CR, % of total impurities and % of total undefined impurities in the reconstituted suspension) with the change of their taste (ie, % pattern discrimination index). ET was able to correlate the results of stability of CR suspension with the change in the taste of the suspension during the shelf life of the reconstituted suspension. Conclusion: The obtained results may suggest the use of ET as a new tool for a rapid assessment of the general quality of a suspension. Moreover, such results would suggest the use of ET to identify fake or substandard products, especially those have been stored under inappropriate storage conditions.


Assuntos
Cefdinir/normas , Medicamentos Fora do Padrão/análise , Cefdinir/análise , Estabilidade de Medicamentos , Nariz Eletrônico , Controle de Qualidade , Suspensões , Paladar , Fatores de Tempo
16.
Eur J Pharm Biopharm ; 145: 12-26, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31622652

RESUMO

A major shortcoming of drug nanocomposites as compared with amorphous solid dispersions (ASDs) is their limited supersaturation capability in dissolution media. Here, we prepared drug hybrid nanocrystal-amorphous solid dispersions (HyNASDs) and compare their performance to ASDs. A wet-milled griseofulvin (GF, BCS II drug) nanosuspension and a GF solution, both containing the same dissolved polymer-surfactant (SDS: sodium dodecyl sulfate) with 1:1 and 1:3 GF:polymer mass ratios, were spray-dried. Hydroxypropyl cellulose (HPC) and Soluplus (Sol) were used as matrix-forming polymers. XRPD, DSC, and Raman spectroscopy reveal that ASDs were formed upon spray-drying the solution-based feed, whereas nanocomposites and nanocomposites with >10% amorphous content, HyNASDs, were formed with the nanosuspension-based feed. Sol provided higher GF relative supersaturation, up to 180% and 360% for HyNASDs and ASDs, respectively, in the dissolution tests than HPC (up to 50% for both) owing to Sol's stronger intermolecular interactions and miscibility with GF and its recrystallization inhibition. Besides the higher kinetic solubility of GF in Sol, presence of GF nanoparticles vs. micron-sized particles in the nanocomposites enabled fast supersaturation. This study demonstrates successful preparation of fast supersaturating (190% within 20 min) HyNASDs, which renders nanoparticle formulations competitive to ASDs in bioavailability enhancement of poorly soluble drugs.


Assuntos
Liberação Controlada de Fármacos/efeitos dos fármacos , Griseofulvina/química , Nanopartículas/química , Celulose/análogos & derivados , Celulose/química , Cristalização/métodos , Composição de Medicamentos/métodos , Nanocompostos/química , Tamanho da Partícula , Polietilenoglicóis/química , Polímeros/química , Polivinil/química , Dodecilsulfato de Sódio/química , Solubilidade , Tensoativos/química , Suspensões/química
17.
AAPS PharmSciTech ; 20(8): 312, 2019 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-31529266

RESUMO

To enhance efficiency, convenience, and safety of Parkinson's disease (PD) treatment for geriatric patients, an advanced suspension of Levodopa/Benserazide hydrochloride (LD/BH) has been prepared by cation-exchange resin and used to synchronize sustained release of LD and BH by optimizing coating parameters and prescription. For the purpose, LD and BH were immobilized on the surface of cation-exchange resin, respectively. Based on HPLC results, the cation-exchange resin showed high loading capacity. The studies on drug loading mechanism indicated that both drugs were immobilized by electrostatic interaction rather than physical adsorption. After PEG modification, pretreated drug-resin complexes were coated by emulsion-solvent evaporation method. In order to control drug release in a sustained manner, coating parameters of drug-resin microcapsules were optimized respectively by single-factor analysis. Further, coating prescription of the microcapsules was optimized to synchronize sustained release of LD and BH in vitro by orthogonal design. Utilizing optimal LD-resin microcapsules and BH-resin microcapsules, LD/BH suspension, containing both of them, was prepared by an optimal formulation and characterized by accelerated test and pharmacokinetic study in vivo. The accelerated test confirmed high stability of LD/BH suspension. According to pharmacokinetic results in vivo, in contrast with LD/BH commercial tablets, LD/BH suspensions did not only synchronize sustained release of both drugs but also show good bioequivalence. As LD/BH sustained release suspension can synchronize sustained release of multiple active ingredients by oral administration, the suspension presents promising oral dosage forms for geriatric patients with PD. An advanced Levodopa/Benserazide hydrochloride (LD/BH) suspension, prepared by cation-exchange resin and optimized microencapsulation, synchronizes sustained releases of LD and BH in vivo to benefit Parkinson's disease treatment for geriatric patients.


Assuntos
Antiparkinsonianos/administração & dosagem , Antiparkinsonianos/química , Benserazida/administração & dosagem , Benserazida/química , Levodopa/administração & dosagem , Levodopa/química , Administração Oral , Animais , Antiparkinsonianos/farmacocinética , Benserazida/farmacocinética , Cápsulas , Resinas de Troca de Cátion , Preparações de Ação Retardada , Combinação de Medicamentos , Composição de Medicamentos , Levodopa/farmacocinética , Lipídeos/química , Masculino , Ratos , Suspensões , Comprimidos com Revestimento Entérico
18.
Environ Sci Pollut Res Int ; 26(32): 32859-32865, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31502053

RESUMO

Grafting polyacrylamide (PAM) chains onto microparticles may combine the advantages of the flocculation property of the former and the fast sedimentation of the later to realize better flocculation performance. In this work, inexpensive microcrystalline cellulose (MCC) microparticles, and monomer of acrylamide (AM) were mixed, and then irradiated under microwave. The obtained material was characterized by Fourier transform infrared spectroscopy and X-ray diffraction, and the results demonstrated successful modification of MCC with AM on the particle surface. The modification procedure has been carefully investigated to obtain an optimum preparation condition. Kaolin suspension was selected as a model to evaluate the flocculation properties of the obtained AM-MCC. Our results indicate that the AM-MCC with the highest grafting ratio of 95.5% exhibits the best flocculation performance, which is even better than that of PAM, and the turbidity can be decreased to 1.4% of the naked kaolin suspension within 2.5 min. Therefore, this work provides a low cost strategy to prepare biodegradable AM-MCC, which may have promising potential application in the water treatment and other fields.


Assuntos
Acrilamida/química , Celulose/química , Micro-Ondas , Purificação da Água/métodos , Resinas Acrílicas , Floculação , Caulim/química , Espectroscopia de Infravermelho com Transformada de Fourier , Suspensões , Difração de Raios X
19.
AAPS PharmSciTech ; 20(7): 305, 2019 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-31506831

RESUMO

The aim of this study was to prepare a 20(S)-protopanaxadiol nanocrystalline suspension and enhance the bioavailability of 20(S)-protopanaxadiol by intramuscular injection. 20(S)-Protopanaxadiol nanocrystalline suspension was prepared using an anti-solvent combined with ultrasonic approach, in which meglumine and bovine serum albumin were screened as the optimized stabilizer and the coating agent during spray drying process, respectively. The optimal nanocrystallines were nearly spherical with a uniform particle size distribution, the mean particle size, polydispersity index, and drug loading of which were 151.20 ± 2.54 nm, 0.11 ± 0.01, and 47.15% (w/w), respectively. Sterile 20(S)-protopanaxadiol nanocrystalline suspension was obtained by passing through a 0.22-µm membrane, and the average filtration efficiency (FE%) was 99.96%. The cumulative release percentage of 20(S)-protopanaxadiol nanocrystalline suspension was 92.36% 20(S)-protopanaxadiol within 60 min in vitro, which was relatively rapid compared with that of the physical mixture for 12.51% and the 20(S)-protopanaxadiol bulk powder for 9.71% during the same time interval. The sterile 20(S)-protopanaxadiol nanocrystalline suspension caused minimal irritation responses by histological examination, indicating a good biocompatibility between the 20(S)-protopanaxadiol nanocrystalline suspension and muscle tissues. In pharmacokinetic study, the absolute bioavailability of 20(S)-protopanaxadiol nanocrystalline suspension for intramuscular injection and for oral gavage was 5.99 and 0.03, respectively. In summary, the 20(S)-protopanaxadiol nanocrystalline via intramuscular injection is an efficient drug delivery system to improve its bioavailability.


Assuntos
Sistemas de Liberação de Medicamentos , Sapogeninas/farmacocinética , Administração Oral , Animais , Disponibilidade Biológica , Injeções Intramusculares , Masculino , Nanopartículas/química , Ratos , Ratos Sprague-Dawley , Sapogeninas/administração & dosagem , Sapogeninas/química , Soroalbumina Bovina/química , Suspensões
20.
Int J Pharm ; 570: 118686, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31513874

RESUMO

Supercritical Emulsion Extraction (SEE) and Supercritical assisted Liposome formation (SuperLip), use dense gases such as carbon dioxide (dCO2) to fabricate advanced micro/nanocarriers. SEE uses dCO2 to extract solvent from the oily phase of an emulsion and obtain biopolymer microbead; For this study, poly-Lactic Acid (PLA) microbeads of 1 ±â€¯0.2 µm in mean size loaded at 1 µg/mgPLA with Rhodamine B (ROD) were prepared by SEE; the beads showed a solvent residue lower than 10 ppm and encapsulated the fluorochrome with an efficiency of 90%. SuperLip uses dCO2 to enhance lipid/ethanol/water mixing and to promote the ethanol extraction from liposome suspension. In this case, phosphatidyl-choline (PC) vesicles with a mean size of 0.2 ±â€¯0.05 µm and loaded with Fluorescein Iso-ThioCyanate (FITC) at 8 µg/mgPC were prepared; small unilamellar structure was observed for all the vesicles with FITC encapsulation efficiency of 80%. Ethanol residue of 50 ppm was measured in all the liposome suspensions. The bioavailability of microbeads and nanoliposomes was assessed through incubation with human monocytes previously isolated from healthy donors' blood. A specifically optimized protocol that allowed their quenching on the cell surface was developed to monitor by flow cytometer assay only the cell population that effectively internalized the carriers. When microbeads were tested, the percentage of alive internalizing monocytes was of about 30%. An internalization of 96.1 ±â€¯21% was, instead, obtained at dosage of 0.1 mg/mL for nanoliposomes. In this last case, monocytes showed a vitality of almost 100% after vesicles internalization at all the concentrations studied; on the other hand, cell apoptosis progressively increased in a dose/response manner, after polymer microbeads phagocytosis. The proposed data suggested that dCO2 technologies can be reliably used to fabricate intracellular carriers.


Assuntos
Dióxido de Carbono/química , Lipossomos/química , Monócitos/metabolismo , Nanopartículas/química , Nanopartículas/metabolismo , Disponibilidade Biológica , Células Cultivadas , Química Farmacêutica/métodos , Portadores de Fármacos/química , Composição de Medicamentos/métodos , Emulsões/química , Citometria de Fluxo/métodos , Humanos , Microesferas , Tamanho da Partícula , Poliésteres/química , Ácido Poliglicólico/química , Rodaminas/química , Solventes/química , Suspensões/química
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