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1.
AAPS PharmSciTech ; 22(5): 193, 2021 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-34184163

RESUMO

The human immunodeficiency virus (HIV) impacts up to 37 million people globally, of which 1.8 million are children. To date, there is no cure for HIV, although treatment options such as antiretroviral therapy (ART) are available. ART, which involves a patient taking a combination of antiretrovirals, is being used to treat HIV clinically. Despite the effectiveness of ART, there is currently no palatable pediatric formulation to treat HIV in children, which has hindered patient compliance and overall treatment efficacy. In addition, anti-HIV therapeutics are often poorly water-soluble, and hence have poor bioavailability. In the present study, we developed a pediatric-friendly formulation for anti-HIV therapeutics with improved dissolution characteristics of the therapeutic agents. Lopinavir (LPV) and ritonavir (RTV), available as FDA-approved fixed-dose combination products, were chosen as model ART drugs, and the formulation and processing parameters of spray-dried cyclodextrin (CD)-based LPV and RTV complexes were studied. Results showed that the spray-dried complexes exhibited enhanced dissolution profiles in comparison to pure drugs, particularly spray-dried ß-CD complexes, which showed the most favorable dissolution profiles. This current formulation with enhanced dissolution and taste-masking ability through the use of cyclodextrin has the potential to address the unmet need for the development of suitable pediatric formulations.


Assuntos
Fármacos Anti-HIV/análise , Fármacos Anti-HIV/síntese química , Ciclodextrinas/análise , Ciclodextrinas/síntese química , Desenvolvimento de Medicamentos/métodos , Secagem por Atomização , Fármacos Anti-HIV/uso terapêutico , Criança , Ciclodextrinas/uso terapêutico , Composição de Medicamentos/métodos , Infecções por HIV/tratamento farmacológico , Humanos , Espectroscopia de Ressonância Magnética/métodos , Pediatria/métodos , Difração de Raios X/métodos
2.
Pharm Dev Technol ; 24(9): 1133-1143, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31327289

RESUMO

Objective: To design and characterize aerosol microparticles (MP) to provide sustained release of the water-soluble compound sulforhodamine B (SRB) and achieve effective aerosol dispersion. Significance: Modulating the release of water-soluble compounds remains a challenge in pulmonary drug delivery. Methods: SRB and water made up an aqueous solution, while acetalated dextran (Ac-Dex) and isopropyl alcohol made up an organic solution. The two solutions were mixed together, and the solution was spray dried to produce MP. MP were characterized for morphology, size, release kinetics, aerosol dispersion, and cellular interactions. Results: Ac-Dex MP exhibited corrugated morphology and aerodynamic diameters from 2.06 to 2.86 µm. MP deposited in all stages of a Next Generation Impactor, with >90% fine particle fraction. MP exhibited encapsulation efficiencies >129% with SRB loading values up to 16.7 µg SRB/mg MP. MP exhibited sustained release of SRB at pH 7 and fast release at pH 5. In vitro experiments showed minimal cytotoxicity, successful uptake of MP in epithelial cells, and no disruption to the integrity of epithelial monolayers. Conclusions: Ac-Dex MP systems demonstrated the ability to provide sustained the release of a water-soluble therapeutic in addition to effective aerosol dispersion for pulmonary applications.


Assuntos
Aerossóis/química , Preparações de Ação Retardada/química , Dextranos/química , Corantes Fluorescentes/administração & dosagem , Rodaminas/administração & dosagem , Acetilação , Administração por Inalação , Cristalização , Liberação Controlada de Fármacos , Inaladores de Pó Seco , Corantes Fluorescentes/química , Pós , Rodaminas/química , Água/química
3.
ACS Biomater Sci Eng ; 5(12): 6570-6580, 2019 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-32133390

RESUMO

Paclitaxel (as intravenous Taxol) is one of the most applied chemotherapeutics used for the treatment of lung cancer. This project involves the development of a dry powder nanocomposite microparticle (nCmP) aerosol containing PTX-loaded nanoparticles (NP) to be delivered via a dry powder inhaler to the lungs for the treatment of non-small cell lung cancer (NSCLC). Nanoparticles were formulated by a single emulsion and solvent evaporation method, producing smooth, neutral PTX NP of approximately 200 nm in size. PTX nCmP were obtained via spray drying PTX NP with mannitol, producing amorphous wrinkled particles that demonstrated optimal aerosol deposition for in vitro pulmonary delivery. Free PTX, PTX NP, and PTX nCmP were evaluated in vitro in both 2D monolayers and 3D multicellular spheroids (MCS). PTX NP enhanced cytotoxicity when compared to pure drug in the 2D evaluation. However, on a liquid culture 3D tumor spheroid model, PTX NP and pure PTX showed similar efficacy in growth inhibition of MCS. The PTX nCmP formulation had a comparable cytotoxicity impact on MCS compared with free PTX. Finally, PTX nCmP were evaluated in an air-grown 3D MCS platform that mimics the pulmonary environment, representing a new model for the assessment of dry powder formulations.

4.
J Pharm Sci ; 106(12): 3539-3547, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28827039

RESUMO

Nanocomposite microparticle (nCmP) systems exhibit promising potential in the application of therapeutics for pulmonary drug delivery. This work aimed at identifying the optimal spray-drying condition(s) to prepare nCmP with specific drug delivery properties including small aerodynamic diameter, effective nanoparticle (NP) redispersion upon nCmP exposure to an aqueous solution, high drug loading, and low water content. Acetalated dextran (Ac-Dex) was used to form NPs, curcumin was used as a model drug, and mannitol was the excipient in the nCmP formulation. Box-Behnken design was applied using Design-Expert software for nCmP parameter optimization. NP ratio (NP%) and feed concentration (Fc) are significant parameters that affect the aerodynamic diameters of nCmP systems. NP% is also a significant parameter that affects the drug loading. Fc is the only parameter that influenced the water content of the particles significantly. All nCmP systems could be completely redispersed into the parent NPs, indicating that none of the factors have an influence on this property within the design range. The optimal spray-drying condition to prepare nCmP with a small aerodynamic diameter, redispersion of the NPs, low water content, and high drug loading is 80% NP%, 0.5% Fc, and an inlet temperature lower than 130°C.


Assuntos
Dextranos/química , Pulmão/efeitos dos fármacos , Nanocompostos/administração & dosagem , Nanocompostos/química , Nanopartículas/administração & dosagem , Nanopartículas/química , Administração por Inalação , Curcumina/química , Sistemas de Liberação de Medicamentos/métodos , Excipientes/química , Manitol/química , Tamanho da Partícula , Temperatura
5.
Int J Cancer ; 141(10): 2143-2153, 2017 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-28771722

RESUMO

Three-dimensional (3 D) cell culture platforms are increasingly being used in cancer research and drug development since they mimic avascular tumors in vitro. In this study, we focused on the development of a novel air-grown multicellular spheroid (MCS) model to mimic in vivo tumors for understanding lung cancer biology and improvement in the evaluation of aerosol anticancer therapeutics. 3 D MCS were formed using A549 lung adenocarcinoma cells, comprising cellular heterogeneity with respect to different proliferative and metabolic gradients. The growth kinetics, morphology and 3 D structure of air-grown MCS were characterized by brightfield, fluorescent and scanning electron microscopy. MCS demonstrated a significant decrease in growth when the tumor-penetrating peptide iRGD and paclitaxel (PTX) were coadministered as compared with PTX alone. It was also found that when treated with both iRGD and PTX, A549 MCS exhibited an increase in apoptosis and decrease in clonogenic survival capacity in contrast to PTX treatment alone. This study demonstrated that coadministration of iRGD resulted in the improvement of the tumor penetration ability of PTX in an in vitro A549 3 D MCS model. In addition, this is the first time a high-throughput air-grown lung cancer tumor spheroid model has been developed and evaluated.


Assuntos
Adenocarcinoma/patologia , Apoptose/efeitos dos fármacos , Técnicas de Cultura de Células/métodos , Neoplasias Pulmonares/patologia , Oligopeptídeos/administração & dosagem , Paclitaxel/farmacologia , Esferoides Celulares/patologia , Adenocarcinoma/tratamento farmacológico , Antineoplásicos Fitogênicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Avaliação de Medicamentos , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Esferoides Celulares/efeitos dos fármacos , Células Tumorais Cultivadas
6.
AAPS PharmSciTech ; 18(8): 3247-3257, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28584899

RESUMO

Pulmonary arterial hypertension (PAH) is an incurable cardiovascular disease characterized by high blood pressure in the arteries leading from the heart to the lungs. Over two million people in the USA are diagnosed with PAH annually and the typical survival rate is only 3 years after diagnosis. Current treatments are insufficient because of limited bioavailability, toxicity, and costs associated with approved therapeutics. Aerosol delivery of drugs is an attractive approach to treat respiratory diseases because it increases localized drug concentration while reducing systemic side effects. In this study, we developed phospholipid-based aerosol microparticles via spray drying consisting of the drug tacrolimus and the excipients dipalmitoylphosphatidylcholine and dipalmitoylphosphatidylglycerol. The phospholipid-based spray-dried aerosol microparticles were shown to be smooth and spherical in size, ranging from 1 to 3 µm in diameter. The microparticles exhibited thermal stability and were amorphous after spray drying. Water content in the microparticles was under 10%, which will allow successful aerosol dispersion and long-term storage stability. In vitro aerosol dispersion showed that the microparticles could successfully deposit in the deep lung, as they exhibited favorable aerodynamic diameters and high fine particle fractions. In vitro dose-response analysis showed that TAC is nontoxic in the low concentrations that would be delivered to the lungs. Overall, this work shows that tacrolimus-loaded phospholipid-based microparticles can be successfully created with optimal physicochemical and toxicological characteristics.


Assuntos
Aerossóis/química , Descoberta de Drogas/métodos , Inaladores de Pó Seco/tendências , Microesferas , Fosfolipídeos/química , Células A549 , Administração por Inalação , Aerossóis/administração & dosagem , Aerossóis/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Relação Dose-Resposta a Droga , Inaladores de Pó Seco/métodos , Excipientes/administração & dosagem , Excipientes/química , Excipientes/metabolismo , Humanos , Hipertensão Pulmonar/tratamento farmacológico , Hipertensão Pulmonar/metabolismo , Tamanho da Partícula , Fosfolipídeos/administração & dosagem , Fosfolipídeos/metabolismo , Resultado do Tratamento
7.
Int J Pharm ; 525(1): 264-274, 2017 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-28450166

RESUMO

Biocompatible, biodegradable polymers are commonly used as excipients to improve the drug delivery properties of aerosol formulations, in which acetalated dextran (Ac-Dex) exhibits promising potential as a polymer in various therapeutic applications. Despite this promise, there is no comprehensive study on the use of Ac-Dex as an excipient for dry powder aerosol formulations. In this study, we developed and characterized pulmonary drug delivery aerosol microparticle systems based on spray-dried Ac-Dex with capabilities of (1) delivering therapeutics to the deep lung, (2) targeting the particles to a desired location within the lungs, and (3) releasing the therapeutics in a controlled fashion. Two types of Ac-Dex, with either rapid or slow degradation rates, were synthesized. Nanocomposite microparticle (nCmP) and microparticle (MP) systems were successfully formulated using both kinds of Ac-Dex as excipients and curcumin as a model drug. The resulting MP were collapsed spheres approximately 1µm in diameter, while the nCmP were similar in size with wrinkled surfaces, and these systems dissociated into 200nm nanoparticles upon reconstitution in water. The drug release rates of the Ac-Dex particles were tuned by modifying the particle size and ratio of fast to slow degrading Ac-Dex. The pH of the environment was also a significant factor that influenced the drug release rate. All nCmP and MP systems exhibited desirable aerodynamic diameters that are suitable for deep lung delivery (e.g. below 5µm). Overall, the engineered Ac-Dex aerosol particle systems have the potential to provide targeted and effective delivery of therapeutics into the deep lung.


Assuntos
Administração por Inalação , Aerossóis/química , Curcumina/administração & dosagem , Dextranos/química , Liberação Controlada de Fármacos , Excipientes/química , Pulmão/efeitos dos fármacos , Tamanho da Partícula , Pós
8.
Int J Pharm ; 512(1): 305-313, 2016 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-27568494

RESUMO

Tacrolimus (TAC) has exhibited promising therapeutic potential in the treatment of pulmonary arterial hypertension (PAH); however, its application is prevented by its poor solubility, instability, poor bioavailability, and negative systemic side effects. To overcome the obstacles of using TAC for the treatment of PAH, we developed nanocomposite microparticles (nCmP) for the pulmonary delivery of tacrolimus in the form of dry powder aerosols. These particles can provide targeted pulmonary delivery, improved solubility of tacrolimus, the potential of penetration through mucus barrier, and controlled drug release. In this system, tacrolimus-loaded polymeric nanoparticles (NP) were prepared via emulsion solvent evaporation and nCmP were prepared by spray drying these NP with mannitol. The NP were approximately 200nm in diameter with narrow size distribution both before loading into and after redispersion from nCmP. The NP exhibited smooth, spherical morphology and the nCmP were raisin-like spheres. High encapsulation efficacy was achieved both in the encapsulation of tacrolimus in NP and that of NP in nCmP. nCmP exhibited desirable aerosol dispersion properties, allowing them to deposit into the deep lung regions for effective drug delivery. A549 cells were used as in vitro models to demonstrate the non-cytotoxicity of TAC nCmP. Overall, the designed nCmP have the potential to aid in the delivery of tacrolimus for the treatment of PAH.


Assuntos
Hipertensão Pulmonar/tratamento farmacológico , Nanocompostos/administração & dosagem , Nanocompostos/química , Tacrolimo/administração & dosagem , Tacrolimo/uso terapêutico , Administração por Inalação , Aerossóis , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Preparações de Ação Retardada/química , Liberação Controlada de Fármacos , Humanos , Nanocompostos/ultraestrutura , Tamanho da Partícula , Pós , Solubilidade , Tacrolimo/farmacocinética , Tacrolimo/farmacologia
9.
Pharm Res ; 33(8): 1862-72, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27091030

RESUMO

PURPOSE: Pulmonary antibiotic delivery is recommended as maintenance therapy for cystic fibrosis (CF) patients who experience chronic infections. However, abnormally thick and sticky mucus present in the respiratory tract of CF patients impairs mucus penetration and limits the efficacy of inhaled antibiotics. To overcome the obstacles of pulmonary antibiotic delivery, we have developed nanocomposite microparticles (nCmP) for the inhalation application of antibiotics in the form of dry powder aerosols. METHODS: Azithromycin-loaded and rapamycin-loaded polymeric nanoparticles (NP) were prepared via nanoprecipitation and nCmP were prepared by spray drying and the physicochemical characteristics were evaluated. RESULTS: The nanoparticles were 200 nm in diameter both before loading into and after redispersion from nCmP. The NP exhibited smooth, spherical morphology and the nCmP were corrugated spheres about 1 µm in diameter. Both drugs were successfully encapsulated into the NP and were released in a sustained manner. The NP were successfully loaded into nCmP with favorable encapsulation efficacy. All materials were stable at manufacturing and storage conditions and nCmP were in an amorphous state after spray drying. nCmP demonstrated desirable aerosol dispersion characteristics, allowing them to deposit into the deep lung regions for effective drug delivery. CONCLUSIONS: The described nCmP have the potential to overcome mucus-limited pulmonary delivery of antibiotics.


Assuntos
Fibrose Cística/tratamento farmacológico , Sistemas de Liberação de Medicamentos/métodos , Nanocompostos/química , Nanopartículas/química , Tamanho da Partícula , Infecções Respiratórias/tratamento farmacológico , Azitromicina/administração & dosagem , Azitromicina/química , Humanos , Nanocompostos/administração & dosagem , Nanopartículas/administração & dosagem , Sirolimo/administração & dosagem , Sirolimo/química , Resultado do Tratamento , Difração de Raios X
10.
Curr Pharm Des ; 22(17): 2522-31, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26831643

RESUMO

BACKGROUND: The use of non-invasive inhaled aerosols for pulmonary drug delivery continues to grow. This is due to the many unique advantages this delivery route offers for the treatment of both local and systemic diseases. The physicochemical properties of the formulated drugs as well as the physiology of the lungs play a key role in both the deposition and absorption of the particles. The airway and the alveolar epithelium are targets for the treatment of respiratory diseases. However, particles have to overcome biological barriers before they reach their target and produce an effect. METHODS: In vitro aerosol dispersion performance (i.e. aerodynamic size and aerodynamic size distribution) of inhalable particles is quantified by inertial impaction, as required by regulatory agencies for an investigational pharmaceutical inhalation aerosol formulation to be approved for use in patients as a marketed pharmaceutical product. Using inertial impaction in conjunction with cell cultures of various pulmonary cells in situ as bioimpactors has unique aspects in correlating aerodynamic properties with pulmonary cellular behavior including viability and uptake. These can be as co-culture or in single culture, as 3-D multicellular spheroids or 2-D cellular monolayer using different conditions to grow them, such as air-liquid interface culture (ALI) or in liquid covered culture (LCC). RESULTS: evaluation of the currently available in vitro models and the challenges in developing reliable cellular tools to predict the deposition of inhalable particles in the lungs as a function of aerodynamic particle properties is presented in the manuscript. CONCLUSION: The mechanistic aerodynamic and biophysical properties of inhaled aerosol particles on the entire respiratory tract at the cellular level based on aerodynamic size and aerodynamic size distribution will be better understood with the development of in vitro methods which are described in this work.


Assuntos
Aerossóis/química , Sistemas de Liberação de Medicamentos , Pulmão/química , Modelos Biológicos , Administração por Inalação , Aerossóis/administração & dosagem , Animais , Células Cultivadas , Humanos , Pulmão/citologia , Pulmão/metabolismo , Tamanho da Partícula
11.
Int J Oncol ; 48(4): 1701-9, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26846376

RESUMO

Three-dimensional (3D) lung multicellular spheroids (MCS) in liquid-covered culture (LCC) and air-interface culture (AIC) conditions have both been developed for the evaluation of aerosol anticancer therapeutics in solution and aerosols, respectively. The MCS were formed by seeding lung cancer cells on top of collagen where they formed spheroids due to the prevalence of cell-to-cell interactions. LCC MCS were exposed to paclitaxel (PTX) in media whereas AIC MCS were exposed to dry powder PEGylated phospholipid aerosol microparticles containing paclitaxel. The difference in viability for 2D versus 3D culture for both LCC and AIC was evaluated along with the effects of the particles on lung epithelium via transepithelial electrical resistance (TEER) measurements. For LCC and AIC conditions, the 3D spheroids were more resistant to treatment with higher IC50 values for A549 and H358 cell lines. TEER results initially indicated a decrease in resistance upon drug or particle exposure, however, these values increased over the course of several days indicating the ability of the cells to recover. Overall, these studies offer a comprehensive in vitro evaluation of aerosol particles used in the treatment of lung cancer while introducing a new method for culturing lung cancer MCS in both LCC and AIC conditions.


Assuntos
Técnicas de Cultura de Células/métodos , Neoplasias Pulmonares/patologia , Esferoides Celulares/patologia , Aerossóis , Antineoplásicos Fitogênicos/farmacologia , Linhagem Celular Tumoral , Avaliação de Medicamentos , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Paclitaxel/farmacologia , Esferoides Celulares/efeitos dos fármacos
12.
Int J Pharm ; 479(2): 320-8, 2015 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-25542988

RESUMO

Targeted pulmonary delivery facilitates the direct application of bioactive materials to the lungs in a controlled manner and provides an exciting platform for targeting magnetic nanoparticles (MNPs) to the lungs. Iron oxide MNPs remotely heat in the presence of an alternating magnetic field (AMF) providing unique opportunities for therapeutic applications such as hyperthermia. In this study, spray drying was used to formulate magnetic nanocomposite microparticles (MnMs) consisting of iron oxide MNPs and d-mannitol. The physicochemical properties of these MnMs were evaluated and the in vitro aerosol dispersion performance of the dry powders was measured by the Next Generation Impactor(®). For all powders, the mass median aerosol diameter (MMAD) was <5µm and deposition patterns revealed that MnMs could deposit throughout the lungs. Heating studies with a custom AMF showed that MNPs retain excellent thermal properties after spray drying into composite dry powders, with specific absorption ratios (SAR)>200W/g, and in vitro studies on a human lung cell line indicated moderate cytotoxicity of these materials. These inhalable composites present a class of materials with many potential applications and pose a promising approach for thermal treatment of the lungs through targeted pulmonary administration of MNPs.


Assuntos
Sistemas de Liberação de Medicamentos , Pulmão/metabolismo , Nanopartículas de Magnetita , Manitol/administração & dosagem , Aerossóis , Linhagem Celular , Química Farmacêutica/métodos , Portadores de Fármacos/química , Composição de Medicamentos , Humanos , Campos Magnéticos , Manitol/química , Manitol/toxicidade , Nanocompostos , Tamanho da Partícula , Pós
13.
AAPS PharmSciTech ; 15(6): 1574-87, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25139763

RESUMO

Inhalable lung surfactant-based carriers composed of synthetic phospholipids, dipalmitoylphosphatidylcholine (DPPC) and dipalmitoylphosphatidylglycerol (DPPG), along with paclitaxel (PTX), were designed and optimized as respirable dry powders using organic solution co-spray-drying particle engineering design. These materials can be used to deliver and treat a wide variety of pulmonary diseases with this current work focusing on lung cancer. In particular, this is the first time dry powder lung surfactant-based particles have been developed and characterized for this purpose. Comprehensive physicochemical characterization was carried out to analyze the particle morphology, surface structure, solid-state transitions, amorphous character, residual water content, and phospholipid bilayer structure. The particle chemical composition was confirmed using attenuated total reflectance-Fourier-transform infrared (ATR-FTIR) spectroscopy. PTX loading was high, as quantified using UV-VIS spectroscopy, and sustained PTX release was measured over weeks. In vitro cellular characterization on lung cancer cells demonstrated the enhanced chemotherapeutic cytotoxic activity of paclitaxel from co-spray-dried DPPC/DPPG (co-SD DPPC/DPPG) lung surfactant-based carrier particles and the cytotoxicity of the particles via pulmonary cell viability analysis, fluorescent microscopy imaging, and transepithelial electrical resistance (TEER) testing at air-interface conditions. In vitro aerosol performance using a Next Generation Impactor™ (NGI™) showed measurable powder deposition on all stages of the NGI and was relatively high on the lower stages (nanometer aerodynamic size). Aerosol dispersion analysis of these high-performing DPIs showed mass median diameters (MMADs) that ranged from 1.9 to 2.3 µm with excellent aerosol dispersion performance as exemplified by high values of emitted dose, fine particle fractions, and respirable fractions.


Assuntos
1,2-Dipalmitoilfosfatidilcolina/química , Antineoplásicos/administração & dosagem , Portadores de Fármacos , Inaladores de Pó Seco , Neoplasias Pulmonares/tratamento farmacológico , Paclitaxel/administração & dosagem , Fosfatidilgliceróis/química , Administração por Inalação , Aerossóis , Antineoplásicos/química , Varredura Diferencial de Calorimetria , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Química Farmacêutica , Cristalografia por Raios X , Preparações de Ação Retardada , Relação Dose-Resposta a Droga , Impedância Elétrica , Desenho de Equipamento , Humanos , Neoplasias Pulmonares/patologia , Microscopia de Fluorescência , Paclitaxel/química , Tamanho da Partícula , Difração de Pó , Pós , Solubilidade , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície , Tecnologia Farmacêutica/métodos , Fatores de Tempo
14.
Acta Biomater ; 10(6): 2622-9, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24486913

RESUMO

One of the current challenges in the systemic delivery of nanoparticles in cancer therapy applications is the lack of effective tumor localization. Iron oxide nanoparticles (IONPs) coated with crosslinked dextran were functionalized with the tumor-homing peptide CREKA, which binds to fibrinogen complexes in the extracellular matrix of tumors. This allows for the homing of these nanoparticles to tumor tissue. The IONP core allows for particle heating upon exposure to an alternating magnetic field (AMF), while the dextran coating stabilizes the particles in suspension and decreases the cytotoxicity of the system. Magnetically mediated hyperthermia (MMH) allows for the heating of tumor tissue to increase the efficacy of traditional cancer treatments using IONPs. While MMH provides the opportunity for localized heating, this method is currently limited by the lack of particle penetration into tumor tissue, even after effective targeted delivery to the tumor site. The CREKA-conjugated nanoparticles presented were characterized for their size, stability, heating capabilities and biocompatibility. The particles had a hydrated diameter of 52nm, were stable in phosphate buffered saline solution and media with 10% v/v fetal bovine serum over at least 12h, and generated enough heat to raise solution temperatures well into the hyperthermia range (41-45°C) when exposed to an AMF, owing to an average specific absorption rate of 83.5Wg(-1). Cytotoxicity studies demonstrated that the particles have low cytotoxicity over long exposure times at low concentrations. A fibrinogen clotting assay was used to determine the binding affinity of CREKA-conjugated particles, which was significantly greater than the binding affinity of dextran, only coated IONPs demonstrating the potential for this particle system to effectively home to a variety of tumor locations. Finally, it was shown that in vitro MMH increased the effects of cisplatin compared with cisplatin or MMH treatments alone.


Assuntos
Compostos Férricos/química , Hipertermia Induzida/métodos , Nanopartículas Metálicas , Oligopeptídeos/administração & dosagem , Microscopia Eletrônica de Transmissão , Oligopeptídeos/síntese química , Espectrofotometria Ultravioleta , Termogravimetria
15.
Eur J Pharm Sci ; 49(4): 699-711, 2013 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-23707466

RESUMO

Pulmonary inhalation chemotherapeutic drug delivery offers many advantages for lung cancer patients in comparison to conventional systemic chemotherapy. Inhalable particles are advantageous in their ability to deliver drug deep in the lung by utilizing optimally sized particles and higher local drug dose delivery. In this work, spray-dried and co-spray dried inhalable lung surfactant-mimic PEGylated lipopolymers as microparticulate/nanoparticulate dry powders containing paclitaxel were rationally designed via organic solution advanced spray drying (no water) in closed-mode from dilute concentration feed solution. Dipalmitoylphosphatidylcholine (DPPC) and dipalmitoylphosphatidylethanolamine poly(ethylene glycol) (DPPE-PEG) with varying PEG chain length were mixed with varying amounts of paclitaxel in methanol to produce co-spray dried microparticles and nanoparticles. Scanning electron microscopy showed the spherical particle morphology of the inhalable particles. Thermal analysis and X-ray powder diffraction confirmed the retention of the phospholipid bilayer structure in the solid-state following spray drying, the degree of solid-state molecular order, and solid-state phase transition behavior. The residual water content of the particles was very low as quantified analytically Karl Fisher titration. The amount of paclitaxel loaded into the particles was quantified which indicated high encapsulation efficiencies (43-99%). Dry powder aerosol dispersion performance was measured in vitro using the Next Generation Impactor (NGI) coupled with the Handihaler dry powder inhaler device and showed mass median aerodynamic diameters in the range of 3.4-7 µm. These results demonstrate that this novel microparticulate/nanoparticulate chemotherapeutic PEGylated phospholipid dry powder inhalation aerosol platform has great potential in lung cancer drug delivery.


Assuntos
1,2-Dipalmitoilfosfatidilcolina/química , Antineoplásicos Fitogênicos/química , Inaladores de Pó Seco , Paclitaxel/química , Fosfatidiletanolaminas/química , Polietilenoglicóis/química , Tensoativos/química , Administração por Inalação , Aerossóis , Antineoplásicos Fitogênicos/administração & dosagem , Dessecação/métodos , Neoplasias Pulmonares/tratamento farmacológico , Paclitaxel/administração & dosagem , Tamanho da Partícula , Tecnologia Farmacêutica
16.
J Biomater Sci Polym Ed ; 24(9): 1112-26, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23683041

RESUMO

Hyperthermia, the heating of tissue from 41 to 45 °C, has been shown to improve the efficacy of cancer therapy when used in conjunction with irradiation and/or chemotherapy. In this work, hydrogel nanocomposites have been developed that can control the delivery of both heat and a chemotherapeutic agent (e.g. paclitaxel). The nanocomposites studied involve a stealth, poly(ethylene glycol) (PEG)-based system comprised of PEG (n = 1000) methyl ether methacrylate and PEG (n = 400) dimethacrylate with iron oxide nanoparticles physically entrapped within the hydrogel matrices. The capability of the hydrogel nanocomposites to be heated in an alternating magnetic field was demonstrated. The heating of the hydrogel systems was dependent on the crosslinking of the hydrogel network where hydrogels with lower swelling ratios were found to heat to a greater extent than those with higher ratios. In addition, paclitaxel was shown to exhibit non-Fickian release from the hydrogel systems, with the amount of drug released dependent on the hydrogel network structure. Three cell lines: M059K (glioblastoma), MDA MB 231 (breast carcinoma), and A549 (lung adenocarcinoma) were exposed to paclitaxel only, hyperthermia only, and both paclitaxel and hyperthermia to determine if a synergistic cytotoxic effect was possible for these cell lines. The efficacy of paclitaxel was greater with hyperthermia for the A549 cells; however, the M059K and MDA MB 231 did not show the same response.


Assuntos
Portadores de Fármacos , Compostos Férricos/química , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Hipertermia Induzida/métodos , Nanopartículas/uso terapêutico , Paclitaxel/administração & dosagem , Polietilenoglicóis/química , Antineoplásicos/administração & dosagem , Linhagem Celular Tumoral , Portadores de Fármacos/síntese química , Portadores de Fármacos/química , Temperatura Alta/uso terapêutico , Humanos , Hidrogel de Polietilenoglicol-Dimetacrilato/síntese química , Hidrogel de Polietilenoglicol-Dimetacrilato/farmacocinética , Hipertermia Induzida/instrumentação , Nanopartículas/administração & dosagem , Nanopartículas/química , Paclitaxel/farmacocinética
17.
Int J Nanomedicine ; 8: 275-93, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23355776

RESUMO

Novel advanced spray-dried and co-spray-dried inhalable lung surfactant-mimic phospholipid and poly(ethylene glycol) (PEG)ylated lipopolymers as microparticulate/nanoparticulate dry powders of biodegradable biocompatible lipopolymers were rationally formulated via an organic solution advanced spray-drying process in closed mode using various phospholipid formulations and rationally chosen spray-drying pump rates. Ratios of dipalmitoylphosphatidylcholine (DPPC) and dipalmitoylphosphatidylethanolamine PEG (DPPE-PEG) with varying PEG lengths were mixed in a dilute methanol solution. Scanning electron microscopy images showed the smooth, spherical particle morphology of the inhalable particles. The size of the particles was statistically analyzed using the scanning electron micrographs and SigmaScan® software and were determined to be 600 nm to 1.2 µm in diameter, which is optimal for deep-lung alveolar penetration. Differential scanning calorimetry (DSC) and powder X-ray diffraction (PXRD) were performed to analyze solid-state transitions and long-range molecular order, respectively, and allowed for the confirmation of the presence of phospholipid bilayers in the solid state of the particles. The residual water content of the particles was very low, as quantified analytically via Karl Fischer titration. The composition of the particles was confirmed using attenuated total-reflectance Fourier-transform infrared (ATR-FTIR) spectroscopy and confocal Raman microscopy (CRM), and chemical imaging confirmed the chemical homogeneity of the particles. The dry powder aerosol dispersion properties were evaluated using the Next Generation Impactor™ (NGI™) coupled with the HandiHaler® dry powder inhaler device, where the mass median aerodynamic diameter from 2.6 to 4.3 µm with excellent aerosol dispersion performance, as exemplified by high values of emitted dose, fine particle fraction, and respirable fraction. Overall, it was determined that the pump rates defined in the spray-drying process had a significant effect on the solid-state particle properties and that a higher pump rate produced the most optimal system. Advanced dry powder inhalers of inhalable lipopolymers for targeted dry powder inhalation delivery were successfully achieved.


Assuntos
1,2-Dipalmitoilfosfatidilcolina/química , Nanopartículas/química , Fosfatidiletanolaminas/química , Polietilenoglicóis/química , Administração por Inalação , Aerossóis/química , Varredura Diferencial de Calorimetria , Inaladores de Pó Seco , Microscopia , Nanomedicina , Tamanho da Partícula , Pós/química , Surfactantes Pulmonares/química , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Água/análise , Difração de Raios X
18.
Int J Pharm ; 431(1-2): 101-10, 2012 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-22548844

RESUMO

Micro- and nanoparticles have been shown to improve the efficacy of safer protein-based (subunit) vaccines. Here, we evaluate a method of improving the vaccine stability outside cold chain conditions by encapsulation of a model enzyme, horseradish peroxidase (HRP), in an acid-sensitive, tunable biodegradable polymer, acetalated dextran (Ac-DEX). Vaccines that are stable outside the cold chain would be desirable for use in developing nations. Ac-DEX particles encapsulating HRP were prepared using two different methods, probe sonication and homogenization. These particles were stored under different storage conditions (-20 °C, 4 °C, 25 °C or 45 °C) for a period of 3 months. On different days, the particles were characterized for various physical and chemical measurements. At all conditions, Ac-DEX particles remained spherical in nature, as compared to PLGA particles that fused together starting at day 3 at 45 °C. Furthermore, our results indicated that encapsulation of HRP in Ac-DEX reduces its storage temperature dependence and enhances its stability outside cold chain conditions. Homogenized particles performed better than probe sonicated particles and retained 70% of the enzyme's initial activity as compared to free HRP that retained only 40% of the initial activity after 3 months of storage at 25 °C or 45 °C. Additionally, HRP activity was more stable when encapsulated in Ac-DEX, and the variance in enzyme activity between the different storage temperatures was not observed for either particle preparation. This suggests that storage at a constant temperature is not required with vaccines encapsulated in Ac-DEX particles. Overall, our results suggest that an Ac-DEX based micro-/nanoparticles system has wide applications as vaccines and drug delivery carriers, including those in developing nations.


Assuntos
Dextranos/química , Peroxidase do Rábano Silvestre/química , Vacinas/química , Portadores de Fármacos , Estabilidade de Medicamentos , Armazenamento de Medicamentos , Peróxido de Hidrogênio/química , Nanopartículas/química , Temperatura
19.
Int J Pharm ; 427(2): 177-84, 2012 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-22326297

RESUMO

Poly(ß-amino ester) (PBAE) biodegradable hydrogels were investigated for potential combined chemotherapeutic and heat delivery in the synergistic treatment of cancer. Hyperthermia, the heating of cancerous tissue from 41 to 45 °C, increases the efficacy of conventional cancer therapies such as irradiation and chemotherapy. The hydrogel nanocomposites in this work provide a drug delivery vehicle (via the biodegradable PBAE polymer network) and the ability to be heated remotely upon exposure to an alternating magnetic field (via iron oxide nanoparticles incorporated into the hydrogel matrix). PBAE macromers composed of poly(ethylene glycol) (N=400) diacrylate (PEG400DA) or diethylene glycol diacrylate (DEGDA) with isobutylamine (IBA) were synthesized. Hydrogel nanocomposites were fabricated via free-radical polymerization to form a bulk hydrogel matrix entrapping both iron oxide nanoparticles and paclitaxel. The 2EG-IBA hydrogel exhibited complete degradation after approximately 7 weeks whereas the 9EG-IBA hydrogel degraded completely in 11h. The hydrogels heated upon exposure to an alternating magnetic field throughout the degradation process. Additionally, the cytotoxicity of the degradation products was evaluated. Paclitaxel release was controlled via bulk degradation of the hydrogels. The tailorability of these nanocomposites makes them solid candidates for the synergistic treatment of cancer.


Assuntos
Antineoplásicos Fitogênicos/administração & dosagem , Compostos Férricos/química , Temperatura Alta , Hidrogéis/química , Nanocompostos/química , Paclitaxel/administração & dosagem , Polímeros/química , Células 3T3/efeitos dos fármacos , Algoritmos , Animais , Antineoplásicos Fitogênicos/farmacologia , Sistemas de Liberação de Medicamentos , Fenômenos Mecânicos , Camundongos , Peso Molecular , Paclitaxel/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier , Termogravimetria
20.
Mol Pharm ; 9(2): 290-8, 2012 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-22149217

RESUMO

We propose the use of a new biopolymer, acetalated dextran (Ac-DEX), to synthesize porous microparticles for pulmonary drug delivery. Ac-DEX is derived from the polysaccharide dextran and, unlike polyesters, has tunable degradation from days to months and pH neutral degradation products. Ac-DEX microparticles fabricated through emulsion techniques were optimized using a variety of postprocessing techniques to enhance the respirable fraction for pulmonary delivery. Tangential flow filtration resulted in a maximum 37% respirable fraction for Ac-DEX porous microparticles, compared to a 10% respirable fraction for poly(lactic-co-glycolic acid) (PLGA) porous microparticles. Ac-DEX microparticles were of an optimum diameter to minimize macrophage clearance but had a low enough theoretical density for deep lung penetration. Transepithelial electrical resistance (TEER) measurements showed that the particles did not impinge on a monolayer of lung epithelial cells in either air or liquid conditions. Also, the release of the chemotherapeutic camptothecin was shown to be tunable depending on Ac-DEX degradation time and molecular weight, and drug release was shown to be bioactive over a range of concentrations. Our results indicate that both release kinetics and fraction of burst release of drug from Ac-DEX porous microparticles can be tuned by simply changing the Ac-DEX polymer properties, affording a large range of formulation options for drug delivery to the pulmonary cavity. Overall, Ac-DEX porous microparticles show promise as an emerging carrier for pulmonary delivery of drugs to the alveolar region of the lung, particularly for the treatment of lung diseases.


Assuntos
Antineoplásicos Fitogênicos/administração & dosagem , Camptotecina/administração & dosagem , Preparações de Ação Retardada/química , Dextranos/química , Pulmão , Macrófagos Alveolares/efeitos dos fármacos , Acetais/química , Administração por Inalação , Antineoplásicos Fitogênicos/química , Camptotecina/química , Linhagem Celular Tumoral , Preparações de Ação Retardada/administração & dosagem , Relação Dose-Resposta a Droga , Humanos , Concentração de Íons de Hidrogênio , Ácido Láctico/química , Macrófagos Alveolares/metabolismo , Microesferas , Peso Molecular , Tamanho da Partícula , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Porosidade
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