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1.
AAPS PharmSciTech ; 20(8): 323, 2019 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-31654184

RESUMO

The most common route of the drug administration is oral route despite the fact that most drugs have low oral aqueous solubility and bioavailability especially for BCS class II and class IV drugs. Many methods have been developed in recent years to overcome the poor solubility and oral bioavailability which includes self-emulsifying drug delivery systems (SEDDS) as one of the approaches. Not only for hydrophobic drugs, but also for hydrophilic compounds with low permeability, bioavailability can be enhanced by self nanoemulsifying drug delivery systems. Recently, a lot of focus and attention has been put in the conversion of liquid SEDDS (L-SEDDS) to solid SEDDS (S-SEDDS) to overcome the limitations of liquid formulations related to their physical and chemical stability, portability, accurate dosing, and limited choices of dosage forms. This article aims to review the formulation components used in SEDDS, various approaches used in the conversion of L-SEDDS to S-SEDDS, their applications, merits, and demerits.


Assuntos
Composição de Medicamentos/métodos , Sistemas de Liberação de Medicamentos/métodos , Emulsões/síntese química , Administração Oral , Disponibilidade Biológica , Emulsões/administração & dosagem , Emulsões/farmacocinética , Interações Hidrofóbicas e Hidrofílicas , Permeabilidade , Solubilidade
2.
Int J Pharm ; 570: 118609, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31415878

RESUMO

Previously, we synthesized 4-(N)-docosahexaenoyl 2', 2'-difluorodeoxycytidine (DHA-dFdC), a novel lipophilic compound with a potent, broad-spectrum antitumor activity. Herein, we report a solid lipid nanoparticle (SLN) formulation of DHA-dFdC with improved apparent aqueous solubility, chemical stability, as well as efficacy in a mouse model. The SLNs were prepared from lecithin/glycerol monostearate-in-water emulsions emulsified with D-α-tocopherol polyethylene glycol 1000 succinate (TPGS) and Tween 20. The resultant DHA-dFdC-SLNs were 102.2 ±â€¯7.3 nm in diameter and increased the apparent solubility of DHA-dFdC in water to at least 5.2 mg/mL, more than 200-fold higher than its intrinsic water solubility. DHA-dFdC in a lyophilized powder of DHA-dFdC-SLNs was significantly more stable than the waxy solid of pure DHA-dFdC. DHA-dFdC-SLNs also showed an increased cytotoxicity against certain tumor cells than DHA-dFdC. The plasma concentration of DHA-dFdC in mice intravenously injected with DHA-dFdC-SLNs in dispersion followed a bi-exponential model, with a half-life of ~44 h. In mice bearing B16-F10 murine melanoma, DHA-dFdC-SLNs were significantly more effective than DHA-dFdC in controlling the tumor growth. In addition, histology evaluation revealed a high level of apoptosis and tumor encapsulation in tumors in mice treated with DHA-dFdC-SLNs. DHA-dFdC-SLNs represents a new DHA-dFdC formulation with improved antitumor activity.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Desoxicitidina/química , Lipídeos/química , Nanopartículas/química , Solubilidade/efeitos dos fármacos , Animais , Linhagem Celular Tumoral , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos/métodos , Emulsões/síntese química , Emulsões/farmacologia , Feminino , Lecitinas/química , Camundongos , Camundongos Endogâmicos C57BL , Tamanho da Partícula , Polietilenoglicóis/química , Vitamina E/química
3.
AAPS PharmSciTech ; 20(7): 297, 2019 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-31444661

RESUMO

Miconazole nitrate (MZ) is a BCS class II antifungal poorly water-soluble drug with limited dissolution properties and gastrointestinal side effects. Self-nanoemulsifying delivery system-based gel of MZ can improve both solubility and oral mucosal absorption with enhanced antifungal activity. The study aims to formulate MZ self-nanoemulsion (MZ-NE) and combine it within hyaluronic acid-based gel. MZ solubility in various oils, surfactants, and cosurfactant used in NE formulations were evaluated. Mixture design was implemented to optimize the levels of NE components as a formulation variable to study their effects on the mean globule size and antifungal inhibition zones. Further, the optimized MZ-NE was loaded into a hyaluronic acid gel base. Rheological behavior of the prepared gel was assessed. Ex vivo permeability of optimized formulation across buccal mucous of sheep and inhibition against Candida albicans were examined. Mixture design was used to optimize the composition of MZ-NE formulation as 22, 67, and 10% for clove oil, Labrasol, and propylene glycol, respectively. The optimized formulation indicated globule size of 113 nm with 29 mm inhibition zone. Pseudoplastic flow with thixotropic behavior was observed, which is desirable for oral gels. The optimized formulation exhibited higher ex vivo skin permeability and enhanced antifungal activity by 1.85 and 2.179, respectively, compared to MZ-SNEDDS, and by 1.52 and 1.72 folds, respectively, compared to marketed gel. Optimized MZ-NE hyaluronic acid-based oral gel demonstrated better antifungal activity, indicating its potential in oral thrush pharmacotherapy.


Assuntos
Antifúngicos/administração & dosagem , Candidíase Bucal/tratamento farmacológico , Química Farmacêutica/métodos , Ácido Hialurônico/administração & dosagem , Miconazol/administração & dosagem , Nanocápsulas/administração & dosagem , Administração Oral , Animais , Antifúngicos/síntese química , Antifúngicos/farmacocinética , Candidíase Bucal/metabolismo , Sistemas de Liberação de Medicamentos/métodos , Avaliação Pré-Clínica de Medicamentos/métodos , Emulsões/administração & dosagem , Emulsões/síntese química , Emulsões/farmacocinética , Ácido Hialurônico/síntese química , Ácido Hialurônico/farmacocinética , Hidrogéis/administração & dosagem , Hidrogéis/síntese química , Hidrogéis/farmacocinética , Miconazol/síntese química , Miconazol/farmacocinética , Nanocápsulas/química , Ovinos
4.
Chem Pharm Bull (Tokyo) ; 67(8): 786-794, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31366828

RESUMO

Teriflunomide (TEF, A771726) is the active metabolite of leflunomide (LEF), a disease-modifying anti-rheumatic drug. The main purpose of this study was to develop and evaluate water-in-oil (W/O) microemulsion formulation of TEF. The W/O microemulsion was optimized formula is the physical and chemical stability of lecithin, ethanol, isopropyl myristate (IPM) and water (20.65/20.78/41.52/17.05 w/w) by using the pseudo-ternary phase diagram and the average droplet size is about 40 nm. The permeability of TEF microemulsion is about 6 times higher than control group in vitro penetration test. The results of anti-inflammatory effect showed that compared with the control group, the external TEF microemulsion group could significantly inhibit swelling of paw in rats, and no significant difference compared with oral LEF group. The results of hepatotoxicity test show that there were normal content of alanine aminotransferase (ALT)/aspartate aminotransferase (AST) and no obvious inflammatory infiltration of TEF microemulsion group compared with LEF group. The plasma concentration curve showed that compared with LEF group, the peak concentration of TEF microemulsion group was decreased, the half-life (t1/2) was prolonged, and the relative bioavailability of TEF microemulsion was 75.35%. These results suggest that TEF W/O microemulsion can be used as a promising preparation to play an anti-inflammatory role while significantly reducing hepatotoxicity.


Assuntos
Antirreumáticos/farmacologia , Crotonatos/farmacologia , Sistemas de Liberação de Medicamentos , Edema/tratamento farmacológico , Toluidinas/farmacologia , Animais , Antirreumáticos/química , Crotonatos/química , Composição de Medicamentos , Edema/patologia , Emulsões/síntese química , Emulsões/química , Estrutura Molecular , Óleos/química , Medição da Dor , Ratos , Ratos Sprague-Dawley , Toluidinas/química , Água/química
5.
J Colloid Interface Sci ; 554: 404-416, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31310879

RESUMO

A novel series of lysine-based ampholytic amphiphiles, with alkylsuccinic anhydrides of varying chain lengths as hydrophobic acylating agents, were synthesized in medium to high yield (50.23-90.15%) based on a facile, catalyst-free method in water medium; and structurally confirmed by mass spectrometry (MS), Fourier transform infra-red (FTIR) spectroscopy, and 1H/13C nuclear magnetic resonances (NMR) analysis. The resulting compounds were subjected to pH-dependent amphiphilic property, ferrous ion chelating, DPPH antioxidant capacity, and cytotoxicity analyses. Results showed that CMC values decrease, γ value increase, and emulsion stability increase with the increase of medium pH, suggesting that the surface activity of synthetic compounds at air/water and oil/water interface under neutral and alkaline conditions was remarkably higher than that under acidic condition. Lauryl O-acylated malic lysine (compound 4b) presented excellent foaming ability close to commercial detergent sodium dodecyl sulphate; dodecyl succinic lysine (compound 4a) afforded highly stable o/w nanoemulsion. Moreover, compound 4b displayed comparable ferrous ion chelating property to lysine and 2,2-diphenyl-1-picrylhydrazyl (DPPH) antioxidative capacity similar to a commercial food ingredient, diacetyl tartaric acid esters of mono- and di-glycerides (DATEM), indicating its multi-faceted functionalities. A cytotoxicity study of compounds 3b &4b showed that they were non-toxic. Thus, these novel ampholytic amphiphiles may find multi-purpose applications in food, detergent, pharmaceutical, and cosmetic industry.


Assuntos
Lisina/síntese química , Anidridos Succínicos/síntese química , Tensoativos/síntese química , Água/química , Alquilação , Antioxidantes/síntese química , Antioxidantes/química , Linhagem Celular , Emulsões/síntese química , Emulsões/química , Humanos , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Lisina/química , Anidridos Succínicos/química , Tensoativos/química
6.
Food Chem Toxicol ; 131: 110552, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31163220

RESUMO

[OBJECTIVE]: Di(2-ethylhexyl) phthalate (DEHP), a widely used plasticizer, may act as an endocrine disruptor and cause developmental toxicity. Differentiated human embryonic stem cells (hESCs) were used to investigate the underlying mechanism of the embryotoxicity induced by DEHP. [Materials and Methods] H9-hESCs were treated with DEHP at different concentrations for 10 days, and the cytotoxicity of DEHP on cell proliferation was determined using a cell-microelectronic sensing technique (Real-Time Cellular Analysis: RTCA). Based on the 50% inhibitory proliferation concentration (IC50), differentiated H9-hESCs were treated with DEHP at 0, 50, 100, and 200 µg/ml for 120 h, followed by measurement of its toxic effects on the transcriptome by mRNA microarray and QuantiGene Plex (QGP). Proteins were detected by the iTRAQ-based proteomics method and the proteins related to the PPARγ/PTEN/Akt pathways were measured by western blotting. The progression of the cell cycle and apoptosis were characterized using flow cytometry (FCM). In other experiments, hESCs were pre-treated with GW9662 (20 µM), a specific PPARγ inhibitor, for 30 min, followed by exposure to GW9662 (20 µM) and DEHP (200 µg/ml) for 120 h to observe the underlying mechanism of DEHP's embryotoxicity. [RESULTS]: DEHP inhibited H9-hESC cell proliferation in a dose-dependent manner, with an IC50 of 165.78 µg/ml. FCM results showed that DEHP could markedly induce cell cycle arrest and increase apoptosis. Gene microarray and QPG array analyses indicated that the peroxisome proliferator-activated receptor γ (PPARγ) was an apparent target for DEHP. We further demonstrated that DEHP could activate the PPARγ and upregulate the expression of PTEN downstream genes, and then play a negative role in the AKT signaling pathway. Cells pretreated with PPARγ inhibitor, GW9662, were shown to restore the effect of DEHP on the PPARγ/PTEN/AKT signaling pathway, and induce the recovery of cell cycle arrest and apoptosis. [CONCLUSION]: DEHP inhibited cell proliferation, promoted cell cycle arrest, and induced apoptosis through the PPARγ/PTEN/AKT signaling pathway in differentiated human embryonic stem cells. It suggested that DEHP exposure possibly cause reproductive or developmental toxicity in humans through the PPARγ signaling pathway.


Assuntos
Apoptose/efeitos dos fármacos , Dietilexilftalato/toxicidade , Disruptores Endócrinos/toxicidade , Células-Tronco Embrionárias Humanas/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Animais , Bovinos , Proliferação de Células/efeitos dos fármacos , Emulsões/síntese química , Emulsões/química , Humanos , PPAR gama/metabolismo , PTEN Fosfo-Hidrolase/metabolismo , Plastificantes/toxicidade , Proteínas Proto-Oncogênicas c-akt/metabolismo , Pontos de Checagem da Fase S do Ciclo Celular/efeitos dos fármacos , Soroalbumina Bovina/química , Teratogênios/toxicidade
7.
Colloids Surf B Biointerfaces ; 181: 244-251, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31151037

RESUMO

In this paper, we report the use of amphiphilic crosslinked starch nanoparticles (CSTNs) as biocompatible, biodegradable and effective stabilizer for Pickering emulsion formulation. The nearly monodispersed CSTNs (˜140 nm) were synthesized through alkali-freezing method followed by crosslinking using citric acid. The prepared nanoparticles were characterized by field emission scanning electron microscopy, zeta-potential measurements, dynamic light scattering, and Fourier transform infrared spectroscopy. The efficacy of the CSTNs toward the stability, the oil droplet size distribution and the surface area moment mean diameter (d3,2) of sunflower oil-in-water emulsions were then assessed as a function of pH. Increase in pH from 3 to 5 and 7.4 led to an enhance in the emulsion stability, decrease in d3,2 and narrowing of the size distribution of emulsions droplets. Moreover, the abundance of nanoparticles increased with pH so that the surface coverage for pH 3, 5 and 7.4 were calculated 10.6, 14.8 and 22.2%, respectively. In vitro controlled release studies showed that the encapsulated curcumin, as a lipophilic and therapeutic compound, into the Pickering emulsion can be tuned by pH of the release media; drug release increases with pH. Collectively, the facile preparation of emulsions stabilized by solid particles derived from biocompatible and renewable resources along with the pH responsivity of these emulsions make them promising drug carriers to treat gastrointestinal tissue disorders via oral drug delivery.


Assuntos
Nanopartículas/química , Amido/química , Tensoativos/química , Materiais Biocompatíveis/síntese química , Materiais Biocompatíveis/química , Emulsões/síntese química , Emulsões/química , Concentração de Íons de Hidrogênio , Tamanho da Partícula , Propriedades de Superfície , Tensoativos/síntese química
8.
Drug Deliv ; 26(1): 168-178, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30822166

RESUMO

The present study aims at designing a thermosensitive gel prepared from w1/o/w2 multiple microemulsions (MMEs) for the vaginal delivery of siRNA. The w1/o/w2 MMEs were prepared by two-step emulsifications: the first step was to prepare primary emulsions (w1/o) by low energy emulsification (LEE); the second step was to obtain stable w1/o/w2 MMEs by self-emulsifying. An extensive formulation optimization process was undertaken. The final w1/o/w2 MMEs could be formed in ddH2O, phosphate buffer solution (PBS, pH 7.4) and 1640 culture media with diameter size about 166.5 ± 13.1, 271.0 ± 11.1 and 278.7 ± 12.1 nm respectively. The release rates of siRNA from solutions, MMEs and MMEs-gels were completed within 2 h, 6 h and13 h respectively. The transfection efficiency of MMEs was confirmed both in vitro and in vivo. The relative target gene expressions of MMEs were 0.07 ± 0.05% vs. 0.37 ± 0.06% in Hela cells against Lipofectamine2000® and 1.88% ± 0.00% vs. 9.65% ± 0.02% in mouse vaginal mucosa against PEI. Good biocompatibility of MMEs was verified by cytotoxicity and pathological studies. Overall, our results indicated the potential of the MMEs-gel system for the vaginal delivery of siRNA.


Assuntos
Administração Intravaginal , Sistemas de Liberação de Medicamentos/métodos , Emulsões/administração & dosagem , Microesferas , Ácidos Nucleicos/administração & dosagem , Tensoativos/administração & dosagem , Animais , Emulsões/síntese química , Emulsões/metabolismo , Feminino , Géis , Células HeLa , Humanos , Camundongos , Ácidos Nucleicos/síntese química , Ácidos Nucleicos/metabolismo , Distribuição Aleatória , Tensoativos/síntese química , Tensoativos/metabolismo , Água/administração & dosagem , Água/química , Água/metabolismo
9.
Colloids Surf B Biointerfaces ; 177: 520-528, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30822627

RESUMO

Tumor eradication has many challenges due to the difficulty of selectively delivering anticancer drugs to malignant cells avoiding contact with healthy tissues/organs. The improvement of antitumor efficacy and the reduction of systemic side effects can be achieved using drug loaded nanoparticles. In this study, poly (ethyl 2-cyanoacrylate) nanoparticles (PECA-NPs) were prepared using an emulsion polymerization method and their potential for cancer treatment was investigated. The size, polydispersity index and zeta potential of prepared nanoparticles are about 80 nm, 0.08 and -39.7 mV, respectively. The stability test shows that the formulation is stable for 15 days, while an increase in particle size occurs after 30 days. TEM reveals the spherical morphology of nanoparticles; furthermore, FTIR and 1H NMR analyses confirm the structure of PECA-NPs and the complete polymerization. The nanoparticles demonstrate an in vitro concentration-dependent cytotoxicity against human epithelial colorectal adenocarcinoma cell lines (Caco-2), as assessed by MTT assay. The anticancer activity of PECA-NPs was studied on 3D tumor spheroids models of hepatocellular carcinoma (HepG2) and kidney adenocarcinoma cells (A498) to better understand how the nanoparticles could interact with a complex structure such as a tumor. The results confirm the antitumor activity of PECA-NPs. Therefore, these systems can be considered good candidates in tumor treatment.


Assuntos
Antineoplásicos/farmacologia , Cianoacrilatos/farmacologia , Nanopartículas/química , Antineoplásicos/síntese química , Antineoplásicos/química , Células CACO-2 , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cianoacrilatos/síntese química , Cianoacrilatos/química , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Emulsões/síntese química , Emulsões/química , Emulsões/farmacologia , Células Hep G2 , Humanos , Tamanho da Partícula , Polimerização , Propriedades de Superfície
10.
Bioconjug Chem ; 30(3): 531-535, 2019 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-30730698

RESUMO

The rapid surface immobilization of protein on monodispersed polyester microcarriers is reported. A model protein, functionalized with a dibenzocyclooctyne core, immobilizes on the surface of azide-terminal polycaprolactone microcarriers within 10 min compared to 12 h for other conjugation techniques, and it is conducted in physiological conditions and in the absence of coupling reagents.


Assuntos
Azidas/química , Química Click/métodos , Proteínas Imobilizadas/química , Poliésteres/química , Albumina Sérica Humana/química , Alquinos/síntese química , Alquinos/química , Azidas/síntese química , Ciclo-Octanos/síntese química , Ciclo-Octanos/química , Emulsões/síntese química , Emulsões/química , Proteínas Imobilizadas/síntese química , Poliésteres/síntese química , Albumina Sérica Humana/síntese química
11.
Biomater Sci ; 7(4): 1623-1631, 2019 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-30702723

RESUMO

Polymers that spontaneously self-assemble in water can form spherical micelles. These micelles are typically used in drug delivery and gene therapeutics. Importantly, the generated emulsion during the process of polymers self-assembly could be crystallized under suitable conditions. The formed crystal structure can enhance the mechanisms of nanoparticle formation. In this study, levodopa-loaded crystallization nanoparticles (LD crystalsomes) were prepared by a mini-emulsion crystallization method. The LD crystalsomes exhibited a positive zeta potential, nanoscale range and longer releasing time for levodopa (LD). Moreover, the therapeutic effects of LD crystalsomes on an MPTP-induced Parkinson's diseases (PD) mouse model were examined. The results showed that pre-administration twice with LD crystalsomes significantly enhanced locomotor activities and climbing times in the PD mouse model. For pathological changes, the numbers of the tyrosine hydroxylases positive neurons (TH+ neuron) of nigral and tyrosine hydroxylases (TH) protein expression of striatum were significantly increased than that in a PD mouse model. Besides, in comparison with bulk LD treatment, the LD crystalsomes administration exhibited better effects on improving behavioral deficits and TH expression. These results suggest that the unique crystalsomes represents a new type of nanoparticle and could be excellent potential drug carriers for drug control and release.


Assuntos
Antiparkinsonianos/uso terapêutico , Levodopa/uso terapêutico , Nanopartículas/química , Doença de Parkinson/tratamento farmacológico , Temperatura Ambiente , Animais , Antiparkinsonianos/síntese química , Antiparkinsonianos/química , Cristalização , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Portadores de Fármacos/química , Emulsões/síntese química , Emulsões/química , Emulsões/uso terapêutico , Feminino , Levodopa/síntese química , Levodopa/química , Camundongos , Camundongos Endogâmicos BALB C , Estrutura Molecular , Relação Estrutura-Atividade
12.
J Oleo Sci ; 68(3): 281-290, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30760674

RESUMO

The effects of pH on the freeze-thaw stability of glycated soy protein isolate (SPI) and soy protein isolate hydrolysate (SPH) were studied. The covalent compounds were prepared by conjugating SPI, SPH and dextran under heated Maillard reaction, which the macromolecules were named SPI-D and SPH-D. SDS-PAGE analysis verified that SPI-D and SPH-D form a covalent bond through the Maillard reaction. Afterwards, the effects of pH on the freeze-thaw stability of SPI, SPI-D and SPH-D emulsions were evaluated. The covalent conjugate stabilized emulsions improved the stability of the emulsions to pH stress. After freeze-thaw cycles, SPH-D revealed the lowest particle size, degree of coalescence (CD) and oiling off. The results above were also supported by optical microscopy analysis.


Assuntos
Dextranos/química , Glicoproteínas/química , Fragmentos de Peptídeos/química , Proteínas de Soja/química , Dextranos/síntese química , Emulsões/síntese química , Emulsões/química , Congelamento , Glicoproteínas/síntese química , Concentração de Íons de Hidrogênio , Tamanho da Partícula , Estabilidade Proteica , Proteólise
13.
Colloids Surf B Biointerfaces ; 177: 321-328, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30771584

RESUMO

Cellulose nanocrystals/fluorinated polyacrylate soap-free emulsion was successfully synthesized via RAFT-assisted Pickering emulsion process using modified cellulose nanocrystals as particle stabilizers. The cellulose nanocrystals were organically modified by linear triblock copolymer poly(2-(dimethylamino) ethyl methacrylate)-b-poly(glycidyl methacrylate)-b-poly(2,2,3,4,4,4-Hexafluorobutyl acrylate) (PDMAEMA-b-PGMA-b-PHFBA) with reactive trithiocarbonate group. Transmission electron microscopy (TEM) and scanning electron microscopy (SEM) analyses showed that modified cellulose nanocrystals were armored on the surface of spherical particles. The morphology and particle size of the resulting products depended on the pH value of particle dispersion. When the value of pH increased from 1.06 to 2.97, the spherical-like particles size decreased from 763 nm to 253 nm. However, with pH value increasing to 6.85, the particle size increased to 394 nm. Furthermore, a possible mechanism for the formation of the cellulose nanocrystals/fluorinated polyacrylate nanoparticles with core-shell structure was proposed.


Assuntos
Celulose/química , Nanopartículas/química , Resinas Acrílicas/química , Emulsões/síntese química , Emulsões/química , Halogenação , Estrutura Molecular , Polimerização , Sabões/química
14.
AAPS PharmSciTech ; 20(2): 65, 2019 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-30627887

RESUMO

Pain nanomedicine is an emerging field in response to current needs of addressing the opioid crisis in the USA and around the world. Our group has focused on the development of macrophage-targeted perfluorocarbon nanoemulsions as inflammatory pain nanomedicines over the past several years. We present here, for the first time, a quality by design approach used to design pain nanomedicine. Specifically, we used failure mode, effects, and criticality analysis (FMECA) which identified the process and composition parameters that were most likely to impact nanoemulsion critical quality attributes (CQAs). From here, we applied a unique combination approach that compared multiple linear regression, boosted decision tree regression, and partial least squares regression methods in combination with correlation plots. The presented combination approach allowed for in-depth analyses of which formulation steps in the nanoemulsification processes control nanoemulsion droplet diameter, stability, and drug loading. We identified that increase in solubilizer (transcutol) content increased drug loading and decreased nanoemulsion stability. This was mitigated by inclusion of perfluorocarbon oil in the internal phase. We observed negative correlation (R2 = 0.4357, p value 0.0054) between the amount of PCE and the percent diameter increase (destabilization), and no correlation between processing parameters and percent diameter increase over time. Further, we identified that increased sonication time decreases nanoemulsion drug loading but does not significantly impact droplet diameter or stability. We believe the methods presented here can be useful in the development of various nanomedicines to produce higher-quality products with enhanced manufacturing and design control.


Assuntos
Analgésicos não Entorpecentes/síntese química , Desenvolvimento de Medicamentos/métodos , Emulsões/síntese química , Fluorcarbonetos/síntese química , Nanopartículas/química , Nanomedicina Teranóstica/métodos , Celecoxib/síntese química , Sonicação
15.
Carbohydr Polym ; 207: 694-703, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30600055

RESUMO

Graphene oxide(GO), as an amphiphilic and biocompatible material, is often used to prepare Pickering emulsion. However, the preparation of stable Pickering emulsion by a low concentration of GO is very challenging. In this research, we prepared the hydrophobic modified hydroxyethyl cellulose (mHEC) which contained quaternary ammonium group and GO which the water contact angle was 84°-86°. A stable, low cost, and biocompatible Pickering emulsion was fabricated by a low concentration of GO and different contents of mHEC. The effects of mHEC concentration, electrolyte concentration, pH, and oil/water ratio on the stability of Pickering emulsion were investigated. What's more, we prepared the biomedical macroporous polyacrylamide hydrogel by the GO/mHEC composite stabilized emulsion template for drug controlled-release. The composite hydrogel by Pickering emulsion template is a potential drug controlled-release delivery platforms. Furthermore, our strategy is extremely versatile, as Pickering particles, polymer and the monomer of hydrogel can all be varied.


Assuntos
Celulose/análogos & derivados , Emulsões/química , Grafite/química , Óxidos/química , Resinas Acrílicas/química , Antineoplásicos/química , Antineoplásicos/farmacologia , Celulose/síntese química , Celulose/química , Doxorrubicina/química , Doxorrubicina/farmacologia , Portadores de Fármacos/síntese química , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Emulsões/síntese química , Células HeLa , Humanos , Hidrogéis/síntese química , Hidrogéis/química , Concentração de Íons de Hidrogênio , Nanopartículas/química , Tamanho da Partícula , Porosidade , Compostos de Amônio Quaternário/síntese química , Compostos de Amônio Quaternário/química
16.
Adv Mater ; 31(38): e1801159, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30260511

RESUMO

With their hierarchical structures and the substantial surface areas, hollow particles have gained immense research interest in biomedical applications. For scalable fabrications, emulsion-based approaches have emerged as facile and versatile strategies. Here, the recent achievements in this field are unfolded via an "emulsion particulate strategy," which addresses the inherent relationship between the process control and the bioactive structures. As such, the interior architectures are manipulated by harnessing the intermediate state during the emulsion revolution (intrinsic strategy), whereas the external structures are dictated by tailoring the building blocks and solidification procedures of the Pickering emulsion (extrinsic strategy). Through integration of the intrinsic and extrinsic emulsion particulate strategy, multifunctional hollow particles demonstrate marked momentum for label-free multiplex detections, stimuli-responsive therapies, and stem cell therapies.


Assuntos
Materiais Biocompatíveis , Animais , Materiais Biocompatíveis/síntese química , Engenharia Química/métodos , Emulsões/síntese química , Humanos
17.
J Agric Food Chem ; 67(4): 1197-1208, 2019 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-30157646

RESUMO

In this study, both zein colloidal particles (ZCPs) and propylene glycol alginate (PGA) were simultaneously applied to prepare novel bilayer emulsions using the method of layer-by-layer (LBL) electrostatic deposition. The effects of different concentrations of PGA as well as incorporating sequences of ZCPs and PGA on physical stability and microstructure of bilayer emulsions were investigated. Furthermore, optical microscopy as well as confocal laser scanning microscopy (CLSM) showed that the oil droplets presented uniform spheres and a compact network appeared in bilayer emulsion. Compared to the Pickering emulsion stabilized by ZCPs alone, novel bilayer emulsions exhibited simultaneous and long-term stability against creaming, coalescence, and Ostwald ripening due to the unique interface framework of a particle-polysaccharide hierarchical structure. Novel bilayer emulsions synergistically stabilized by colloidal particles and biopolymers were designed by using interfacial engineering, and a promising pathway was found to produce stable bilayer emulsions for the delivery of bioactive compounds.


Assuntos
Alginatos/química , Emulsões/química , Zeína/química , Emulsões/síntese química , Tamanho da Partícula
18.
J Colloid Interface Sci ; 536: 80-87, 2019 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-30359887

RESUMO

HYPOTHESIS: This study compared the interfacial and emulsification properties of tea saponins, quillaja saponins, and Tween 80. We hypothesized that tea saponins are an effective and sustainable source of plant-based emulsifiers that could replace synthetic or animal-based emulsifiers in many commercial applications. EXPERIMENTS: Interfacial tension measurements were used to characterize the behavior of the three surfactants at an oil-water interface. The emulsifying properties of the surfactants were determined by preparing oil-in-water emulsions containing 10 wt% medium chain triglycerides (MCT) and varying surfactant levels (0.1-2 wt%) using high-pressure homogenization (pH 7). The impact of surfactant type on emulsion formation and stability was determined by measuring particle size, zeta-potential, microstructure, and creaming stability. FINDINGS: The tea saponins were capable of producing nano-scale droplets (d32 < 200 nm) at low surfactant-to-oil ratios (SOR < 0.1). Emulsions containing tea saponins remained stable to droplet aggregation when exposed to various temperatures (30-90 °C), salt levels (0-200 mM NaCl), and pH values (3-9). However, droplet flocculation and/or coalescence occurred under highly acidic (pH 2) and high ionic strength (300-500 mM NaCl) conditions. Tea saponin-coated oil droplets appeared to be mainly stabilized by a combination of electrostatic and steric repulsion. The tea saponins behaved similarly or better than the other two emulsifiers under most conditions. These results suggest that tea saponins are effective plant-based surfactants that may have applications in commercial products.


Assuntos
Produtos Biológicos/química , Nanopartículas/química , Polissorbatos/química , Saponinas/química , Tensoativos/química , Produtos Biológicos/síntese química , Emulsões/síntese química , Emulsões/química , Tamanho da Partícula , Polissorbatos/síntese química , Quillaja/química , Saponinas/síntese química , Propriedades de Superfície , Tensoativos/síntese química , Chá/química
19.
Nano Lett ; 19(1): 173-181, 2019 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-30543289

RESUMO

Phase-change contrast agents are rapidly developing as an alternative to microbubbles for ultrasound imaging and therapy. These agents are synthesized and delivered as liquid droplets and vaporized locally to produce image contrast. They can be used like conventional microbubbles but with the added benefit of reduced size and improved stability. Droplet-based agents can be synthesized with diameters on the order of 100 nm, making them an ideal candidate for extravascular imaging or therapy. However, their synthesis requires low boiling point perfluorocarbons (PFCs) to achieve activation (i.e., vaporization) thresholds within FDA approved limits. Minimizing spontaneous vaporization while producing liquid droplets using conventional methods with low boiling point PFCs can be challenging. In this study, a new method to produce PFC nanodroplets using spontaneous nucleation is demonstrated using PFCs with boiling points ranging from -37 to 56 °C. Sometimes referred to as the ouzo method, the process relies on saturating a cosolvent with the PFC before adding a poor solvent to reduce solvent quality, forcing droplets to spontaneously nucleate. This approach can produce droplets ranging from under 100 nm to over 1 µm in diameter. Ternary plots showing solvent and PFC concentrations leading to droplet nucleation are presented. Additionally, acoustic activation thresholds and size distributions with varying PFC and solvent conditions are measured and discussed. Finally, ultrasound contrast imaging is demonstrated using ouzo droplets in an animal model.


Assuntos
Meios de Contraste/química , Fluorcarbonetos/química , Medula Espinal/diagnóstico por imagem , Ultrassonografia/métodos , Animais , Meios de Contraste/síntese química , Meios de Contraste/farmacologia , Emulsões/síntese química , Emulsões/química , Emulsões/farmacologia , Fluorcarbonetos/síntese química , Fluorcarbonetos/farmacologia , Gases/química , Humanos , Microbolhas , Tamanho da Partícula , Ratos , Volatilização
20.
J Agric Food Chem ; 67(4): 1209-1221, 2019 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-30571105

RESUMO

Novel bilayer emulsions co-stabilized by zein colloidal particles (ZCPs) and propylene glycol alginate (PGA) were designed to overcome some limitations of conventional emulsions or Pickering emulsions. The bilayer emulsions of various concentrations of PGA (0.01-1.50%, w/v) and different incorporation sequences of ZCPs and PGA (ZCPs/PGA and PGA/ZCPs) were fabricated using the layer by layer (LBL) electrostatic deposition technique. Influence of environmental stresses (pH 2.5-8.5; temperature 60-80 °C ; ionic strength 0-100 mM NaCl) was focused on the stability and rheological properties of the novel bilayer emulsions. In comparison to the Pickering emulsion stabilized by ZCPs alone, bilayer emulsions exhibited improved stability and unique rheological characteristics under environmental stresses. The microstructure of well-defined spheres existing a branchlike network was observed in bilayer emulsions by TEM. A comprehensive evaluation was made of the physical characteristics and stimuli-responsive behavior of bilayer emulsions. The result provided meaningful information for understanding the changing mechanism of rheology of bilayer emulsions under environmental stresses.


Assuntos
Alginatos/química , Emulsões/química , Zeína/química , Emulsões/síntese química , Temperatura Alta , Concentração de Íons de Hidrogênio , Concentração Osmolar , Tamanho da Partícula , Reologia
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