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1.
Asia Pac J Clin Nutr ; 31(3): 543-550, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36173226

RESUMO

BACKGROUND AND OBJECTIVES: Assess the different nutritional status between admission and discharged in older adult patients using the GLIM criteria. METHODS AND STUDY DESIGN: A retrospective analysis was conducted on a multicenter study which initiated in 34 hospitals in China with 2734 hospitalized older patients. The dynamic changes of malnutrition according to GLIM criteria were performed between at admission and discharge, and their significance was analyzed using the chi-square test. The association between malnutrition and clinical outcomes was analyzed using the chi-square test, t-test, or rank sum test, and divided into different disease types for further analysis. RESULTS: The incidence of nutritional risk in elderly patients was 51.6% at admission and 48.4% at discharge. The prevalence of malnutrition according to the GLIM criteria was 19.6% at admission and increased to 33.4% at discharge, which was significantly different. Different age and disease type were related with nutrition status. Malnutrition is significantly association with adverse clinical outcomes such as increased risk of complications and prolonged length of hospital stay. CONCLUSIONS: The GLIM criteria can be used in elderly patients to assess malnutrition. The prevalence of malnutrition in elderly inpatients is high, and the prevalence of malnutrition at discharge is higher than that observed at admission. Attention should be paid to the dynamic changes of malnutrition in elderly patients during hospitalization.


Assuntos
Desnutrição , Avaliação Nutricional , Idoso , Hospitalização , Humanos , Desnutrição/epidemiologia , Estado Nutricional , Estudos Retrospectivos
2.
Drug Dev Ind Pharm ; 47(11): 1700-1712, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35287534

RESUMO

Nanocrystal technology is a new way to increase the solubility and bioavailability of poorly soluble drugs. As an intermediate preparation technology, nanocrystals are widely used in drug delivery for oral, venous, percutneous and inhalation administration, which exhibits a broad application prospect. By referring to the domestic anforeign literatures, this paper mainly reviews the preparation methods of nanocrystals for poorly soluble natural products and its application in the mucosal delivery for skin, eye, oral cavity and nasal cavity. This can provide the reference for the research and development of nanocrystal technology in natural product preparations.


Assuntos
Nanopartículas , Disponibilidade Biológica , Sistemas de Liberação de Medicamentos/métodos , Nanopartículas/química , Preparações Farmacêuticas/química , Solubilidade
3.
AAPS PharmSciTech ; 18(5): 1572-1584, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27620195

RESUMO

Poorly water-soluble drugs offer challenges in developing a formulation product with adequate bioavailability. This study took advantage of the features of nanocrystals and direct compression technologies to develop a novel solid self-nanodispersion delivery system for andrographolide (Andro) in order to increase its dissolution rate for enhancing bioavailability. Andro nanosuspensions (Andro-NS) with a particle size of about 500 nm were prepared by homogenization technology and further converted into dried nanocrystal particles (Andro-NP) via spray-drying. The solid self-nanodispersion delivery system (Andro-SNDS)-loaded Andro-NP was prepared via direct compression technology. The DSC and PXRD results demonstrated that the Andro nanocrystals retained its original crystallinity. The dissolution of the Andro-SNDS formulation was 85.87% in pure water over 30 min, better than those of the coarse Andro and physical mixture of Andro and stabilizer. And the C max (299.32 ± 78.54 ng/mL) and AUC0-∞ (4440.55 ± 764.13 mg/L · h) of the Andro-SNDS formulation were significantly higher (p < 0.05) than those of the crude Andro (77.52 ± 31.73 ng/mL and 1437.79 ± 354.25 mg/L · h). The AUC of the Andro-SNDS was 3.09 times as high as that of the crude Andro. This study illustrated a novel approach to combine the features of nanocrystals and composite particles used to improve oral bioavailability of poorly soluble drug.


Assuntos
Diterpenos , Sistemas de Liberação de Medicamentos , Animais , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/farmacocinética , Disponibilidade Biológica , Dessecação , Diterpenos/administração & dosagem , Diterpenos/farmacocinética , Composição de Medicamentos/métodos , Nanopartículas/química , Tamanho da Partícula , Solubilidade
4.
AAPS PharmSciTech ; 18(7): 2744-2753, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28341935

RESUMO

The objective of this study is to prepare a novel drug nanosuspension modified by a natural triterpenoid saponin (glycyrrhizin (GZ)) and evaluate its stability and redispersibility. A poorly soluble drug (andrographolide (AGE)) was used as a model drug. AGE nanosuspensions (AGE-NS) using GZ as natural stabilizer with mean particle size of 487 nm were firstly prepared by homogenization and converted into dried AGE nanosuspension powder (AGE-NP) by freeze-drying. It was found that GZ was able to prevent the aggregation of AGE nanocrystals and the freeze-dried AGE-NP could easily redisperse back to AGE-NS. It was related with special properties of GZ that possessed the interfacial property (37.02 ± 0.29 N/m) and electrostatic effect (-43.6 ± 0.9 mV) and could entrap AGE nanocrystals into its network structure. The freeze-dried AGE-NP/GZ exhibited excellent performance, compared with those combined with trehalose as matrix formers. The powder X-ray diffraction result demonstrated that GZ did not alter the AGE crystal state. The dissolution of AGE-NP/GZ (99.87%) was significantly enhanced, compared with the coarse AGE (42.35%). This study demonstrated that GZ could be used as a novel multifunctional stabilizer for production of drug nanosuspensions and provided a promising basis for further formulation development of poorly soluble drug.


Assuntos
Diterpenos/química , Ácido Glicirrízico/química , Estabilidade de Medicamentos , Liofilização , Nanopartículas/química , Pós , Solubilidade , Suspensões
5.
J Pharm Sci ; 113(3): 699-710, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-37659720

RESUMO

The oral bioavailability of poorly soluble drugs has always been the focus of pharmaceutical researchers. We innovatively combined nanocrystal technology and solid dispersion technology to prepare novel nanocrystalline solid dispersions (NCSDs), which enable both the solidification and redispersion of nanocrystals, offering a promising new pathway for oral delivery of insoluble Chinese medicine ingredients. The rubusoside (Rub) was first used as the multifunctional stabilizer of novel apigenin nanocrystal-based solid dispersions (AP-NSD), improving the in vitro solubilization rate of the insoluble drug apigenin(AP). AP-NSD has been produced using a combination of homogenisation and spray-drying technology. The effects of stabilizer type and concentration on AP nanosuspensions (AP-NS) particles, span, and zeta potential were studied. And the effects of different types of protective agents on the yield and redispersibility of AP-NSD were also studied. Furthermore, AP-NSD was characterized by infrared spectroscopy (IR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), differential scanning calorimetry (DSC), and powder X-ray diffraction (PXRD). Solubility was used to assess the in vitro dissolution of AP-NSD relative to APIs and amorphous solid dispersions (AP-ASD), and AP-ASD was prepared by the solvent method. The results showed that 20% Rub stabilized AP-NSD exhibited high drug-loading and good redispersibility and stability, and higher in vitro dissolution rate, which may be related to the presence of Rub on surface of drug. Therefore provides a natural and safe option for the development of formulations for insoluble drugs.


Assuntos
Apigenina , Diterpenos do Tipo Caurano , Glucosídeos , Nanopartículas , Preparações Farmacêuticas , Composição de Medicamentos/métodos , Excipientes , Difração de Raios X , Nanopartículas/química , Solubilidade , Varredura Diferencial de Calorimetria , Espectroscopia de Infravermelho com Transformada de Fourier
6.
Biomater Sci ; 11(3): 1013-1030, 2023 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36545798

RESUMO

Multiple gastrointestinal barriers (mucus clearance and epithelium barrier) are the main challenges in the oral administration of nanocarriers. To achieve efficient mucus penetration and epithelial absorption, a novel strategy based on mesoporous silica nanoparticles with dendritic superstructure, hydrophilicity, and nearly neutral-charged modification was designed. The mPEG covalently grafted dendritic mesoporous silica nanoparticles (mPEG-DMSNs) had a particle size of about 200 nm and a loading capacity of up to 50% andrographolide (AG) as a nanocrystal cluster in the mesoporous structure. This dual strategy of combining with the surface topography structure and hydrophilic modification maintained a high mucus permeability and showed an increase in cell absorption. The mPEG-DMSN formulation also exhibited effective transepithelial transport and intestinal tract distribution. The pharmacokinetics study demonstrated that compared with other AG formulations, the andrographolide nanocrystals-loaded mPEG-DMSN (AG@mPEG-DMSN) exhibited much higher bioavailability. Also, AG@mPEG-DMSN could significantly improve the in vitro and in vivo anti-inflammatory efficacy of AG. In summary, mPEG-DMSN offers an interesting strategy to overcome the mucus clearance and epithelium barriers of the gastrointestinal tract.


Assuntos
Portadores de Fármacos , Nanopartículas , Portadores de Fármacos/química , Dióxido de Silício/química , Nanopartículas/química , Absorção Intestinal , Administração Oral , Muco
7.
Drug Deliv ; 29(1): 637-651, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35188021

RESUMO

Pulmonary inhalation administration is an ideal approach to locally treat lung disease and to achieve systemic administration for other diseases. However, the complex nature of the structural characteristics of the lungs often results in the difficulty in the development of lung inhalation preparations. Nanocrystals technology provides a potential formulation strategy for the pulmonary delivery of poorly soluble drugs, owing to the decreased particle size of drug, which is a potential approach to overcome the physiological barrier existing in the lungs and significantly increased bioavailability of drugs. The pulmonary inhalation administration has attracted considerable attentions in recent years. This review discusses the barriers for pulmonary drug delivery and the recent advance of the nanocrystals in pulmonary inhalation delivery. The presence of nanocrystals opens up new prospects for the development of novel pulmonary delivery system. The particle size control, physical instability, potential cytotoxicity, and clearance mechanism of inhaled nanocrystals based formulations are the major considerations in formulation development.


Assuntos
Portadores de Fármacos/farmacocinética , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Administração por Inalação , Sobrevivência Celular/efeitos dos fármacos , Química Farmacêutica/métodos , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Estabilidade de Medicamentos , Liofilização/métodos , Macrófagos Alveolares/metabolismo , Nanopartículas/química , Tamanho da Partícula , Surfactantes Pulmonares/farmacologia , Solubilidade , Tecnologia Farmacêutica/métodos
8.
Pharmaceutics ; 14(3)2022 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-35335914

RESUMO

To effectively achieve the pulmonary delivery for curcumin (CN), novel inhalable mucus-penetrating nanocrystal-based microparticles (INMP) were designed. The D-Tocopherol acid polyethylene glycol 1000 succinate (TPGS) modified CN nanocrystals (CN-NS@TPGS) were prepared by high pressure homogenization and further converted into nanocrystal-based microparticles (CN-INMP@TPGS) using spray-drying. It was demonstrated that CN-NS@TPGS exhibited little interaction with the negatively charged mucin due to a strong electrostatic repulsion effect and PEG hydrophilic chain, and exhibited a much higher penetration ability across the mucus layer compared with poloxamer 407 modified CN-NS (CN-NS@P407) and tween 80 modified CN-NS (CN-NS@TW80). The aerodynamic results demonstrated that the CN-INMP with 10% TPGS acting as the stabilizer presented a high FPF value, indicating excellent deposition in the lung after inhalation administration. Additionally, in vivo bioavailability studies indicated that the AUC(0-t) of CN-INMP@TPGS (2413.18 ± 432.41 µg/L h) were 1.497- and 3.32-fold larger compared with those of CN-INMP@TW80 (1612.35 ± 261.35 µg/L h) and CN-INMP@P407 (3.103 ± 196.81 µg/L h), respectively. These results indicated that the CN-INMP@TPGS were absorbed rapidly after pulmonary administration and resulted in increased systemic absorption. Therefore, the inhalable CN-INMP could significantly improve the bioavailability of CN after inhalation administration. The developed mucus-penetrating nanocrystals-in-microparticles might be regarded as a promising formulation strategy for the pulmonary administration of poorly soluble drugs.

9.
Int J Biol Macromol ; 183: 2314-2325, 2021 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-34087300

RESUMO

Novel peppermint oil (PO)-loaded composite microcapsules (CM) with hydroxypropyl methyl cellulose (HPMC)/chitosan/silica shells were effectively fabricated by PO Pickering emulsion, which were stabilized with chitosan-decorated silica nanoparticles (CSN). The surface modification of chitosan could improve the hydrophobicity of silica nanoparticles and favor their adsorption at the oil-water interface of PO Pickering emulsions. The microcapsule composite shells were formed dependent on the electrostatic adsorption of HPMC and CSN, and further subjected to spray-drying. The peppermint oil-loaded composite microcapsules with 100% HPMC as wall material (PO-CM@100%HPMC) seemed to be optimum formulation based on the prolonged release, acceptable entrapment efficiency (89.1%) and drug loading (25.5%). The PO-CM@100%HPMC could remarkably prolong the stability of PO. Moreover, the PO-CM@100%HPMC had a long-term antimicrobial activity (85.4%) against S. aureus and E. coli even after storage for 60 days. Therefore, the Pickering emulsions based microcapsules seemed to be a promising strategy for antibacterial application for PO.


Assuntos
Antibacterianos/farmacologia , Quitosana/química , Portadores de Fármacos , Escherichia coli/efeitos dos fármacos , Nanopartículas , Óleos de Plantas/farmacologia , Dióxido de Silício/química , Staphylococcus aureus/efeitos dos fármacos , Adsorção , Antibacterianos/química , Cápsulas , Preparações de Ação Retardada , Composição de Medicamentos , Liberação Controlada de Fármacos , Estabilidade de Medicamentos , Emulsões , Escherichia coli/crescimento & desenvolvimento , Interações Hidrofóbicas e Hidrofílicas , Derivados da Hipromelose/química , Mentha piperita , Óleos de Plantas/química , Staphylococcus aureus/crescimento & desenvolvimento , Fatores de Tempo
10.
Int J Pharm ; 594: 120182, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33346126

RESUMO

The objective of this study is to use a carbohydrate polymer deacetylated gellan gum (DGG) as matrix to design nanocrystals based intranasal in situ gel (IG) for nose-to -brain delivery of drug. The harmine nanocrystals (HAR-NC) as model drug were prepared by coupling homogenization and spray-drying technology. The HAR-NC was redispersed in the (DGG) solutions and formed the ionic-triggered harmine nanocrystals based in situ gel (HAR-NC-IG). The crystal state of HAR remained unchanged during the homogenization and spray-drying. And the HAR-NC-IG with 0.5% DGG exhibited excellent in situ-gelation ability, water retention property and in vitro release behavior. The bioavailability in brain of intranasal HAR-NC-IG were 25-fold higher than that of oral HAR-NC, which could be attributed to nanosizing effect of HAR-NC and bioadhesive property of DGG triggered by nasal fluid. And the HAR-NC-IG could significantly inhibit the expression of acetylcholinesterase (AchE) and increase the content of acetylcholin (ACh) in brain compared with those of reference formulations (p < 0.01). The DGG based nanocrystals-in situ gel was a promising carrier for nose-to-brain delivery of poorly soluble drug, which could prolong the residence time and improve the bioavailability of poorly soluble drugs in brain.


Assuntos
Nanopartículas , Encéfalo , Géis , Nanogéis , Polissacarídeos Bacterianos
11.
Int J Nanomedicine ; 15: 10385-10399, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33376327

RESUMO

Gambogic acid (GA), a kind of dry resin secreted by the Garcinia hanburyi tree, is a natural active ingredient with various biological activities, such as anti-cancer, anti-inflammatory, antioxidant, anti-bacterial effects, etc. An increasing amount of evidence indicates that GA has obvious anti-cancer effects via various molecular mechanisms, including the induction of apoptosis, autophagy, cell cycle arrest and the inhibition of invasion, metastasis, angiogenesis. In order to improve the efficacy in cancer treatment, nanometer drug delivery systems have been employed to load GA and form micelles, nanoparticles, nanofibers, and so on. In this review, we aim to offer a summary of chemical structure and properties, anti-cancer activities, drug delivery systems and combination therapy of GA, which might provide a reference to promote the development and clinical application of GA.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Xantonas/administração & dosagem , Xantonas/farmacologia , Antineoplásicos Fitogênicos/administração & dosagem , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Sistemas de Liberação de Medicamentos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Garcinia/química , Humanos , Micelas , Nanoestruturas , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Neovascularização Patológica/tratamento farmacológico , Xantonas/química
12.
Int J Pharm ; 575: 118945, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31830576

RESUMO

The objective of this study was to understand the influence of the water adsorption and glass transition of matrix formers on redispersibility in water of drug nanocrystals-aggregated particles(NAP) during storage, and the critical storage strategy for NAP powders were determined based on the Guggenheim-Anderson-de Boer (GAB) and the Gordon-Taylor models. Apigenin was used as model drug. Six kinds of matrix formers sucrose(SU), lactose(LA), trehalose(TR), inulin(IN), maltodextrin(MA) and PVPK30(PV) were used to prepare apigenin nanocrystals-aggregated particles (AN-NAPs). The results demonstrated that the adsorption isotherms curves of six kinds of matrix formers based AN-NAPs all showed typical II (S) type adsorption. The water activity significantly influenced the redispersibility of AN-NAP, which could be attributed to the microstructure collapse of amorphous matrix induced by moisture adsorption at high water activity or high moisture. MD based AN-NAP(AN-NAP/MD) exhibited much better redispersibility at high water activity(0.689) compared with the other amorphous matrix formers. MD was able to significantly enlarge the Tg of AN-NAP system and prevent from aggregation of AN-NAP compared to other matrix formers. And the critical water activity and moisture content of AN-NAPs were in the ranges of 0.015-0.545 and 0.0412-0.1508 g water/g dry matter, respectively. Of all amorphous matrix based NAPs, the critical water activity of AN-NAP/MD was the highest (0.545), and the critical moisture content was 0.1003 g water/g dry matter, and followed by TR based on AN-NAP. MD could be used as an excellent matrix former for nanocrystals-aggregated particles during storage. Therefore, the roles of water adsorption and glass transition of matrix formers on redispersibility of drug nanocrystals-aggregated particles during storage was successful elucidated, and the critical storage strategy was proposed based on the GAB model and the Gordon-Taylor model.


Assuntos
Apigenina/administração & dosagem , Excipientes/química , Nanopartículas/química , Tecnologia Farmacêutica/métodos , Água/química , Adsorção , Portadores de Fármacos/química , Estabilidade de Medicamentos , Pós/química , Temperatura , Vitrificação
13.
Int J Nanomedicine ; 15: 10435-10451, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33380794

RESUMO

PURPOSE: Nose-to-brain drug delivery is an effective approach for poorly soluble drugs to bypass the blood-brain barrier. A new drug intranasal delivery system, a nanosuspension-based in situ gel, was developed and evaluated to improve the solubility and bioavailability of the drug and to prolong its retention time in the nasal cavity. MATERIALS AND METHODS: Breviscapine (BRE) was chosen as the model drug. BRE nanosuspensions (BRE-NS) were converted into BRE nanosuspension powders (BRE-NP). A BRE nanosuspension in situ gelling system (BRE-NG) was prepared by mixing BRE-NP and 0.5% gellan gum (m/v). First, the BRE-NP were evaluated in terms of particle size and by differential scanning calorimetry (DSC), powder X-ray diffraction (PXRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Subsequently, the critical ionic concentration of the gellan gum phase transition, influence of the deacetylated gellan gum (DGG) concentration on the expansion coefficient (S%), water-holding capacity, rheological properties and in vitro release behaviour of the BRE-NG were investigated. The pharmacokinetics and brain distribution of the BRE-NG after intranasal administration were compared with those of the intravenously injected BRE-NP nanosuspensions in rats. RESULTS: The rheology results demonstrated that BRE-NG was a non-Newtonian fluid with good spreadability and bioadhesion performance. Moreover, the absolute bioavailability estimated for BRE-NG after intranasal administration was 57.12%. The drug targeting efficiency (DTE%) of BRE in the cerebrum, cerebellum and olfactory bulb was 4006, 999 and 3290, respectively. The nose-to-brain direct transport percentage (DTP%) of the cerebrum, cerebellum and olfactory bulb was 0.975, 0.950 and 0.970, respectively. CONCLUSION: It was concluded that the in situ gel significantly increased the drug retention time at the administration site. Therefore, the nanosuspension-based in situ gel could be a convenient and effective intranasal formulation for the administration of BRE.


Assuntos
Encéfalo/efeitos dos fármacos , Sistemas de Liberação de Medicamentos/métodos , Flavonoides/administração & dosagem , Flavonoides/farmacocinética , Nanoestruturas/administração & dosagem , Administração Intranasal , Animais , Disponibilidade Biológica , Varredura Diferencial de Calorimetria , Liberação Controlada de Fármacos , Géis/administração & dosagem , Masculino , Nanoestruturas/química , Tamanho da Partícula , Polissacarídeos Bacterianos/química , Polissorbatos/química , Ratos Sprague-Dawley , Reologia , Solubilidade , Difração de Raios X
14.
Colloids Surf B Biointerfaces ; 175: 333-342, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30554011

RESUMO

Breviscapine (BVP) is a flavonoid compound with strong neuroprotective and anti-platelet aggregation effect. The objective of this study is to design novel BVP nanocrystals modified by natural panax notoginseng saponins (PNS) for enhancing dissolution and anti-platelet aggregation effect of BVP. BVP nanocrystals modified by PNS (BVP-NC/PNS) were firstly prepared by coupling homogenization technology and freeze-drying technology, and BVP nanocrystals modified by RH40 (BVP-NC/RH40) as reference for comparison. The morphology, crystals characterization, dissolution behavior and anti-platelet aggregation effect of BVP-NC/PNS was systemically evaluated. The results demonstrated that the PNS could effectively maintain stability of BVP-NC at suspensions state dependent of its surface activity and the electrostatic repulsion effect. Combination of PNS and trehalose could prevent the aggregation of BVP-NC/PNS during freeze-drying. The PXRD and DSC results demonstrated that the BVP crystal state in BVP-NC/PNS was not changed owing to PNS modification and homogenization treatment. And the freeze-dried BVP-NC could easily recover back to BVP-NS and significantly improve the dissolution of BVP. The AUC(0-∞) of the BVP-NC/PNS was 4.54 times as high as that of the coarse BVP, but not significantly different compared to that of BVP-NC/RH40 (p < 0.05). The anti-platelet aggregation results demonstrated that, BVP-NC/PNS group showed more effective inhibition on PAF-induced platelet aggregation compared with corresponding control groups, which might attribute to the enhanced bioavailability of BVP and synergistic effect of PNS with BVP. In conclusion, PNS could be used as an alternative stabilizer for preparation of BVP-NC, and BVP-NC modified by PNS is a promising formulation strategy for enhancing oral bioavailability and anti-platelet aggregation of BVP.


Assuntos
Flavonoides/farmacocinética , Nanopartículas/química , Panax notoginseng/química , Inibidores da Agregação Plaquetária/farmacocinética , Saponinas/química , Administração Oral , Animais , Disponibilidade Biológica , Flavonoides/química , Flavonoides/farmacologia , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Nanopartículas/ultraestrutura , Tamanho da Partícula , Agregação Plaquetária/efeitos dos fármacos , Inibidores da Agregação Plaquetária/química , Inibidores da Agregação Plaquetária/farmacologia , Ratos , Difração de Raios X
15.
Carbohydr Polym ; 213: 128-137, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-30879652

RESUMO

The objective of this study is to use cellulose nanocrystals (CNC) combining with carboxymethyl cellulose sodium (CMC-Na) and hydroxypropyl methylcellulose (HPMC) as stabilizer to prepare novel redispersible camellia oil Pickering emulsions powder (CO-PEP). Cellulose nanocrystals modified with carboxymethyl cellulose sodium (CNCC) was prepared by homogenization technology. CNCC seemed to be rod-like particles with mean particle size of 124.2 ± 2.5 nm. And the cellulose structure, crystal state and thermal property of CNCC remained unchanged during the homogenization. The combination of CNC and CMC-Na in CNCC might be dependent of physical interaction. The mean particle size of optimum CO-PE/0.25%CNCC was 0.569 ± 0.023 µm. The CNCC based particle stabilizer might form the distinctive barrier layer around oil droplet. The redispersibility results demonstrated that 50% HPMC based CO-PEP formed large composite particle with high drug loading ability and exhibited superior redispersibility. Novel redispersible powdered Pickering emulsions could be prepared by cellulose nanocrystals combining with water-soluble cellulosic derivatives.


Assuntos
Celulose/química , Nanopartículas/química , Pós , Celulose/análogos & derivados , Emulsões/química , Tamanho da Partícula , Propriedades de Superfície
16.
Colloids Surf B Biointerfaces ; 160: 619-627, 2017 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-29031222

RESUMO

To help baicalin pass across BBB and improve its targeting in brain, we designed a novel formulation strategy of baicalin nanocrystals that preferentially adsorbing apolipoprotein E (ApoE) and repelling protein adsorption of opsonins. Intravenous baicalin nanocrystals suspensions (BCL-NS) modified by different surfactant were prepared by high-pressure homogenization. The targeting potential of surface-modified BCL-NS with mean particles size of about 250nm was assessed by in vitro protein adsorption studies using two-dimensional polyacrylamide gel electrophoresis (2-D PAGE), and further evaluated in vivo pharmacokinetics. The protein adsorption results showed that BCL-NS/TPGS, BCL-NS/TW80 and BCL-NS/TPGS+TW80 adsorbed very high amounts of apolipoproteins (ApoA-I, ApoA-Ⅱ, ApoA-IV, ApoC-III, ApoE, ApoJ) and relative low amounts of opsonins (fibrinogen, immunoglobulin heavy chain gamma, immunoglobulin light chain). The pharmacokinetics results demonstrated the AUC (0-∞) in brain of the BCL-NS/TW80+TPGS was 6.67 times as high as that of the BCL solution, and 2.59 times as high as that of the BCL-NS/TW80. It could be attributed to the most ApoE and Apo J adsorption indicative of strong BBB penetration, and least IgG γ and fibrinogen loading minimizing the risk of hepatic uptake. Combination of TW80 and TPGS can be rational choice of surfactants of baicalin nanocrystals for brain-targeting mediated by ApoE adsorption.


Assuntos
Apolipoproteínas/metabolismo , Encéfalo/metabolismo , Flavonoides/metabolismo , Nanopartículas/química , Polissorbatos/química , Vitamina E/química , Adsorção , Animais , Apolipoproteínas/química , Área Sob a Curva , Barreira Hematoencefálica/metabolismo , Flavonoides/química , Flavonoides/farmacocinética , Humanos , Masculino , Microscopia Eletrônica de Transmissão , Nanopartículas/ultraestrutura , Tamanho da Partícula , Ratos Wistar , Suspensões/química
17.
Int J Nanomedicine ; 11: 4187-97, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27616886

RESUMO

PURPOSE: This study was designed to improve the in vivo pharmacokinetics of long-circulating vincristine sulfate (VS)-loaded liposomes; three different long-circulating materials, chitosan, poly(ethylene glycol)-1,2-distearoyl sn-glycero-3-phosphatidylethanolamine (PEG-DSPE), and poly(ethylene glycol)-poly-lactide-co-glycolide (PEG-PLGA), were evaluated at the same coating molar ratio with the commercial product Marqibo(®) (vincristine sulfate liposome injection [VSLI]). MATERIALS AND METHODS: VS-loaded liposomes were prepared by a pH gradient method and were then coated with chitosan, PEG-DSPE, or PEG-PLGA. Physicochemical properties, including the morphology, particle size, zeta potential, encapsulation efficiency (EE%), pH, drug loading, and in vitro release, were determined. Preservation stability and pharmacokinetic studies were performed to compare the membrane-coated liposomes with either commercially available liposomes or the VS solution. RESULTS: The sphere-like morphology of the vesicles was confirmed by transmission electron microscope. Increased particle size, especially for the chitosan formulation, was observed after the coating process. However, the EE% was ~99.0% with drug loading at 2.0 mg/mL, which did not change after the coating process. The coating of long-circulation materials, except for chitosan, resulted in negatively charged and stable vesicles at physiological pH. The near-zero zeta potential exhibited by the PEG-DSPE formulation leads to a longer circulation lifetime and improved absorption for VS, when compared with the PEG-PLGA formulation. Compared with the commercial product, PEG was responsible for a higher plasma VS concentration and a longer half-life. CONCLUSION: PEG-DSPE coating may be related to better absorption, based on the stability and a pharmacokinetic improvement in the blood circulation time.


Assuntos
Fosfatidiletanolaminas/química , Poliésteres/química , Polietilenoglicóis/química , Vincristina/farmacocinética , Animais , Quitosana/química , Sistemas de Liberação de Medicamentos , Meia-Vida , Concentração de Íons de Hidrogênio , Lipossomos/química , Masculino , Microscopia Eletrônica de Transmissão , Tamanho da Partícula , Ratos
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