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1.
Small ; 18(15): e2200449, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35229498

RESUMEN

A surface adsorption strategy is developed to enable the engineering of microcomposites featured with ultrahigh loading capacity and precise ratiometric control of co-encapsulated peptides. In this strategy, peptide molecules (insulin, exenatide, and bivalirudin) are formulated into nanoparticles and their surface is decorated with carrier polymers. This polymer layer blocks the phase transfer of peptide nanoparticles from oil to water and, consequently, realizes ultrahigh peptide loading degree (up to 78.9%). After surface decoration, all three nanoparticles are expected to exhibit the properties of adsorbed polymer materials, which enables the co-encapsulation of insulin, exenatide, and bivalirudin with a precise ratiometric control. After solidification of this adsorbed polymer layer, the release of peptides is synchronously prolonged. With the help of encapsulation, insulin achieves 8 days of glycemic control in type 1 diabetic rats with one single injection. The co-delivery of insulin and exenatide (1:1) efficiently controls the glycemic level in type 2 diabetic rats for 8 days. Weekly administration of insulin and exenatide co-encapsulated microcomposite effectively reduces the weight gain and glycosylated hemoglobin level in type 2 diabetic rats. The surface adsorption strategy sets a new paradigm to improve the pharmacokinetic and pharmacological performance of peptides, especially for the combination of peptides.


Asunto(s)
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Adsorción , Animales , Glucemia , Diabetes Mellitus Experimental/tratamiento farmacológico , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Exenatida/uso terapéutico , Hipoglucemiantes/uso terapéutico , Insulina/uso terapéutico , Péptidos/farmacología , Polímeros/química , Ratas
2.
Small ; 15(24): e1901427, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-31062448

RESUMEN

The surface modification of nanoparticles (NPs) using different ligands is a common strategy to increase NP-cell interactions. Here, dentin phosphophoryn-derived peptide (DSS) lignin nanoparticles (LNPs) are prepared and characterized, the cellular internalization of the DSS-functionalized LNPs (LNPs-DSS) into three different cancer cell lines is evaluated, and their efficacy with the widely used iRGD peptide is compared. It is shown that controlled extent of carboxylation of lignin improves the stability at physiological conditions of LNPs formed upon solvent exchange. Functionalization with DSS and iRGD peptides maintains the spherical morphology and moderate polydispersity of LNPs. The LNPs exhibit good cytocompatibility when cultured with PC3-MM2, MDA-MB-231, and A549 in the conventional 2D model and in the 3D cell spheroid morphology. Importantly, the 3D cell models reveal augmented internalization of peptide-functionalized LNPs and improve antiproliferative effects when the LNPs are loaded with a cytotoxic compound. Overall, LNPs-DSS show equal or even superior cellular internalization than the LNPs-iRGD, suggesting that DSS can also be used to enhance the cellular uptake of NPs into different types of cells, and release different cargos intracellularly.


Asunto(s)
Antineoplásicos/administración & dosificación , Portadores de Fármacos/síntesis química , Portadores de Fármacos/farmacocinética , Proteínas de la Matriz Extracelular/química , Lignina/química , Nanopartículas/química , Fosfoproteínas/química , Sialoglicoproteínas/química , Células A549 , Antineoplásicos/farmacocinética , Transporte Biológico/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Portadores de Fármacos/química , Liberación de Fármacos , Humanos , Ensayo de Materiales , Células PC-3 , Péptidos/química , Esferoides Celulares/efectos de los fármacos , Esferoides Celulares/metabolismo , Células Tumorales Cultivadas
3.
Small ; 14(27): e1800462, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29855134

RESUMEN

The last decade has seen remarkable advances in the development of drug delivery systems as alternative to parenteral injection-based delivery of insulin. Neonatal Fc receptor (FcRn)-mediated transcytosis has been recently proposed as a strategy to increase the transport of drugs across the intestinal epithelium. FcRn-targeted nanoparticles (NPs) could hijack the FcRn transcytotic pathway and cross the epithelial cell layer. In this study, a novel nanoparticulate system for insulin delivery based on porous silicon NPs is proposed. After surface conjugation with albumin and loading with insulin, the NPs are encapsulated into a pH-responsive polymeric particle by nanoprecipitation. The developed NP formulation shows controlled size and homogeneous size distribution. Transmission electron microscopy (TEM) images show successful encapsulation of the NPs into pH-sensitive polymeric particles. No insulin release is detected at acidic conditions, but a controlled release profile is observed at intestinal pH. Toxicity studies show high compatibility of the NPs with intestinal cells. In vitro insulin permeation across the intestinal epithelium shows approximately fivefold increase when insulin is loaded into FcRn-targeted NPs. Overall, these FcRn-targeted NPs offer a toolbox in the development of targeted therapies for oral delivery of insulin.


Asunto(s)
Albúminas/química , Antígenos de Histocompatibilidad Clase I/química , Insulina/química , Nanopartículas/química , Polímeros/química , Receptores Fc/química , Silicio/química , Concentración de Iones de Hidrógeno , Microscopía Electrónica de Transmisión , Nanopartículas/ultraestructura , Porosidad
4.
Biomacromolecules ; 19(10): 3983-3993, 2018 10 08.
Artículo en Inglés | MEDLINE | ID: mdl-30207704

RESUMEN

Pharmaceutical nanosuspensions are formed when drug crystals are suspended in aqueous media in the presence of stabilizers. This technology offers a convenient way to enhance the dissolution of poorly water-soluble drug compounds. The stabilizers exert their action through electrostatic or steric interactions, however, the molecular requirements of stabilizing agents have not been studied extensively. Here, four structurally related amphiphilic Janus-dendrimers were synthesized and screened to determine the roles of different macromolecular domains on the stabilization of drug crystals. Physical interaction and nanomilling experiments have substantiated that Janus-dendrimers with fourth generation hydrophilic dendrons were superior to third generation analogues and Poloxamer 188 in stabilizing indomethacin suspensions. Contact angle and surface plasmon resonance measurements support the hypothesis that Janus-dendrimers bind to indomethacin surfaces via hydrophobic interactions and that the number of hydrophobic alkyl tails determines the adsorption kinetics of the Janus-dendrimers. The results showed that amphiphilic Janus-dendrimers adsorb onto drug particles and thus can be used to provide steric stabilization against aggregation and recrystallization. The modular synthetic route for new amphiphilic Janus-dendrimers offers, thus, for the first time a versatile platform for stable general-use stabilizing agents of drug suspensions.


Asunto(s)
Dendrímeros/química , Indometacina/química , Poloxámero/química , Tensoactivos/química , Agua/química , Interacciones Hidrofóbicas e Hidrofílicas , Suspensiones
5.
AAPS PharmSciTech ; 18(5): 1554-1563, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27604883

RESUMEN

In this study, the feasibility of ultrasonic processing (UP) technique as green preparation method for production of poorly soluble model drug substance, diacerein, loaded niosomes was demonstrated. Also, the effects of different surfactant systems on niosomes' characteristics were analyzed. Niosomes were prepared using both the green UP technique and traditional thin-film hydration (TFH) technique, which requires the use of environmentally hazardous organic solvents. The studied surfactant systems were Span 20, Pluronic L64, and their mixture (Span 20 and Pluronic L64). Both the production techniques produced well-defined spherical vesicles, but the UP technique produced smaller and more monodisperse niosomes than TFH. The entrapment efficiencies with the UP method were lower than with TFH, but still at a feasible level. All the niosomal formulations released diacerein faster than pure drug, and the drug release rates from the niosomes produced by the UP method were higher than those from the TFH-produced niosomes. With UP technique, the optimum process conditions for small niosomal products with low PDI values and high entrapment efficiencies were obtained when 70% amplitude and 45-min sonication time were used. The overall results demonstrated the potency of UP technique as an alternative fast, cost-effective, and green preparation approach for production of niosomes, which can be utilized as drug carrier systems for poorly soluble drug materials.


Asunto(s)
Antraquinonas , Hexosas , Poloxámero , Antraquinonas/administración & dosificación , Antraquinonas/farmacocinética , Antiinflamatorios/administración & dosificación , Antiinflamatorios/farmacocinética , Portadores de Fármacos/farmacología , Composición de Medicamentos/métodos , Sistemas de Liberación de Medicamentos/métodos , Liberación de Fármacos , Estudios de Factibilidad , Tecnología Química Verde/métodos , Hexosas/química , Hexosas/farmacología , Liposomas , Poloxámero/química , Poloxámero/farmacología , Tensoactivos/química , Tensoactivos/farmacología , Ultrasonido/métodos
6.
Pharm Res ; 32(2): 628-39, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25145336

RESUMEN

PURPOSE: The lack of effective screening methods and systemic understanding of interaction mechanisms complicates the stabilizer selection process for nanocrystallization. This study focuses on the efficiency of stabilizers with various molecular compositions and structures to stabilize drug nanocrystals. METHODS: Five structurally different polymers were chosen as stabilizers for indomethacin nanocrystals. The affinity of polymers onto drug surfaces was measured using surface plasmon resonance (SPR) and contact angle techniques. Nanosuspensions were prepared using the wet-ball milling technique and their physico-chemical properties were thoroughly characterized. RESULTS: SPR and contact angle measurements correlated very well with each other and showed that the binding efficiency decreased in the order L64 > 17R4 > F68 ≈ T908 ≈ T1107, which is attributed to the reduced PPO/PEO ratio and different polymer structures. The electrostatic interactions between the protonated amine of poloxamines and ionized indomethacin enhanced neither the affinity nor the properties of nanosuspensions, such as particle size and physical stability. CONCLUSIONS: A good stabilizer should have high binding efficiency, full coverage, and optimal hydrophobic/hydrophilic balance. A high affinity combined with short PEO chains (L64, 17R4) caused poor physical stability of nanosuspensions, whereas moderate binding efficiencies (F68, T908, T1107) with longer PEO chains produced physically stable nanosuspensions.


Asunto(s)
Excipientes/metabolismo , Indometacina/metabolismo , Nanopartículas/metabolismo , Polietilenglicoles/metabolismo , Glicoles de Propileno/metabolismo , Interacciones Farmacológicas , Excipientes/química , Indometacina/química , Nanopartículas/química , Polietilenglicoles/química , Polímeros/química , Polímeros/metabolismo , Glicoles de Propileno/química , Resonancia por Plasmón de Superficie/métodos
7.
Small ; 10(10): 2029-38, 2014 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-24616278

RESUMEN

We report an advanced drug delivery platform for combination chemotherapy by concurrently incorporating two different drugs into microcompoistes with ratiometric control over the loading degree. Atorvastatin and celecoxib were selected as model drugs due to their different physicochemical properties and synergetic effect on colorectal cancer prevention and inhibition. To be effective in colorectal cancer prevention and inhibition, the produced microcomposite contained hypromellose acetate succinate, which is insoluble in acidic conditions but highly dissolving at neutral or alkaline pH conditions. Taking advantage of the large pore volume of porous silicon (PSi), atorvastatin was firstly loaded into the PSi matrix, and then encapsulated into the pH-responsive polymer microparticles containing celecoxib by microfluidics in order to obtain multi-drug loaded polymer/PSi microcomposites. The prepared microcomposites showed monodisperse size distribution, multistage pH-response, precise ratiometric controlled loading degree towards the simultaneously loaded drug molecules, and tailored release kinetics of the loaded cargos. This attractive microcomposite platform protects the payloads from being released at low pH-values, and enhances their release at higher pH-values, which can be further used for colon cancer prevention and treatment. Overall, the pH-responsive polymer/PSi-based microcomposite can be used as a universal platform for the delivery of different drug molecules for combination therapy.


Asunto(s)
Preparaciones de Acción Retardada/síntesis química , Composición de Medicamentos/instrumentación , Concentración de Iones de Hidrógeno , Microfluídica/instrumentación , Nanocápsulas/química , Silicio/química , Cristalización/instrumentación , Cristalización/métodos , Difusión , Composición de Medicamentos/métodos , Diseño de Fármacos , Diseño de Equipo , Análisis de Falla de Equipo , Cinética , Ensayo de Materiales , Microfluídica/métodos , Nanocápsulas/ultraestructura , Nanoconjugados/química , Nanoconjugados/ultraestructura , Tamaño de la Partícula , Polímeros/química , Porosidad
8.
Macromol Rapid Commun ; 35(6): 624-9, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24497275

RESUMEN

Currently, developing a stable nanocarrier with high cellular internalization and low toxicity is a key bottleneck in nanomedicine. Here, we have developed a successful method to covalently conjugate poly(methyl vinyl ether-co-maleic acid) (PMVE-MA) copolymer on the surface of (3-aminopropyl)triethoxysilane-functionalized thermally carbonized porous silicon nanoparticles (APSTCPSi NPs), forming a surface negatively charged nanovehicle with unique properties. This polymer conjugated NPs could modify surface smoothness, charge, and hydrophilicity of the developed NPs, leading to considerable improvement in the colloidal and plasma stabilities via enhanced suspensibility and charge repulsion. Furthermore, despite the surface negative charge of the polymer-conjugated NPs, the cellular internalization was increased in both MDA-MB-231 and MCF-7 breast cancer cells. These results provide a proof-of-concept evidence that such polymer-based PSi nanocomposite can be extensively used as a promising candidate for intracellular drug delivery.


Asunto(s)
Células/citología , Nanopartículas/química , Polímeros/química , Silicio/química , Adhesión Celular , Línea Celular Tumoral , Supervivencia Celular , Humanos , Porosidad
9.
Int J Pharm ; 655: 124070, 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38554740

RESUMEN

The importance of ink rheology to the outcome of 3D printing is well recognized. However, rheological properties of printing inks containing drug nanocrystals have not been widely investigated. Therefore, the objective of this study was to establish a correlation between the composition of nanocrystal printing ink, the ink rheology, and the entire printing process. Indomethacin was used as a model poorly soluble drug to produce nanosuspensions with improved solubility properties through particle size reduction. The nanosuspensions were further developed into semisolid extrusion 3D printing inks with varying nanocrystal and poloxamer 407 concentrations. Nanocrystals were found to affect the rheological properties of the printing inks both by being less self-supporting and having higher yielding resistances. During printing, nozzle blockages occurred. Nevertheless, all inks were found to be printable. Finally, the rheological properties of the inks were successfully correlated with various printing and product properties. Overall, these experiments shed new light on the rheological properties of printing inks containing nanocrystals.


Asunto(s)
Nanopartículas , Poloxámero , Geles , Excipientes/química , Impresión Tridimensional , Reología , Tinta
10.
ACS Appl Mater Interfaces ; 16(15): 18643-18657, 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38564504

RESUMEN

Musculoskeletal diseases involving tissue injury comprise tendon, ligament, and muscle injury. Recently, macrophages have been identified as key players in the tendon repair process, but no therapeutic strategy involving dual drug delivery and gene delivery to macrophages has been developed for targeting the two main dysregulated aspects of macrophages in tendinopathy, i.e., inflammation and fibrosis. Herein, the anti-inflammatory and antifibrotic effects of dual-loaded budesonide and serpine1 siRNA lipid-polymer hybrid nanoparticles (LPNs) are evaluated in murine and human macrophage cells. The modulation of the gene and protein expression of factors associated with inflammation and fibrosis in tendinopathy is demonstrated by real time polymerase chain reaction and Western blot. Macrophage polarization to the M2 phenotype and a decrease in the production of pro-inflammatory cytokines are confirmed in macrophage cell lines and primary cells. The increase in the activity of a matrix metalloproteinase involved in tissue remodelling is proven, and studies evaluating the interactions of LPNs with T cells proved that dual-loaded LPNs act specifically on macrophages and do not induce any collateral effects on T cells. Overall, these dual-loaded LPNs are a promising combinatorial therapeutic strategy with immunomodulatory and antifibrotic effects in dysregulated macrophages in the context of tendinopathy.


Asunto(s)
Nanopartículas , Tendinopatía , Animales , Humanos , Ratones , Polímeros , ARN Interferente Pequeño/genética , Budesonida , Macrófagos , Inflamación , Lípidos , Fibrosis
11.
J Colloid Interface Sci ; 633: 383-395, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36462264

RESUMEN

The use of amphiphilic block copolymers to generate colloidal delivery systems for hydrophobic drugs has been the subject of extensive research, with several formulations reaching the clinical development stages. However, to generate particles of uniform size and morphology, with high encapsulation efficiency, yield and batch-to-batch reproducibility remains a challenge, and various microfluidic technologies have been explored to tackle these issues. Herein, we report the development and optimization of poly(ethylene glycol)-block-(ε-caprolactone) (PEG-b-PCL) nanoparticles for intravenous delivery of a model drug, sorafenib. We developed and optimized a glass capillary microfluidic nanoprecipitation process and studied systematically the effects of formulation and process parameters, including different purification techniques, on product quality and batch-to-batch variation. The optimized formulation delivered particles with a spherical morphology, small particle size (dH < 80 nm), uniform size distribution (PDI < 0.2), and high drug loading degree (16 %) at 54 % encapsulation efficiency. Furthermore, the stability and in vitro drug release were evaluated, showing that sorafenib was released from the NPs in a sustained manner over several days. Overall, the study demonstrates a microfluidic approach to produce sorafenib-loaded PEG-b-PCL NPs and provides important insight into the effects of nanoprecipitation parameters and downstream processing on product quality.


Asunto(s)
Nanopartículas , Neoplasias , Humanos , Sorafenib , Portadores de Fármacos/química , Microfluídica , Reproducibilidad de los Resultados , Poliésteres/química , Polietilenglicoles/química , Nanopartículas/química , Tamaño de la Partícula
12.
Adv Mater ; 35(22): e2211254, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36802103

RESUMEN

Microparticles are successfully engineered through controlled interfacial self-assembly of polymers to harmonize ultrahigh drug loading with zero-order release of protein payloads. To address their poor miscibility with carrier materials, protein molecules are transformed into nanoparticles, whose surfaces are covered with polymer molecules. This polymer layer hinders the transfer of cargo nanoparticles from oil to water, achieving superior encapsulation efficiency (up to 99.9%). To control payload release, the polymer density at the oil-water interface is enhanced, forming a compact shell for microparticles. The resultant microparticles can harvest up to 49.9% mass fraction of proteins with zero-order release kinetics in vivo, enabling an efficient glycemic control in type 1 diabetes. Moreover, the precise control of engineering process offered through continuous flow results in high batch-to-batch reproducibility and, ultimately, excellent scale-up feasibility.


Asunto(s)
Nanopartículas , Polímeros , Reproducibilidad de los Resultados , Agua
13.
ACS Biomater Sci Eng ; 8(10): 4132-4139, 2022 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-34292713

RESUMEN

Porous silicon (PSi) nanoparticles have been applied in various fields, such as catalysis, imaging, and biomedical applications, because of their large specific surface area, easily modifiable surface chemistry, biocompatibility, and biodegradability. For biomedical applications, it is important to precisely control the surface modification of PSi-based materials and quantify the functionalization density, which determines the nanoparticle's behavior in the biological system. Therefore, we propose here an optimized solution to quantify the functionalization groups on PSi, based on the nuclear magnetic resonance (NMR) method by combining the hydrolysis with standard 1H NMR experiments. We optimized the hydrolysis conditions to degrade the PSi, providing mobility to the molecules for NMR detection. The NMR parameters were also optimized by relaxation delay and the number of scans to provide reliable NMR spectra. With an internal standard, we quantitatively analyzed the surficial amine groups and their sequential modification of polyethylene glycol. Our investigation provides a reliable, fast, and straightforward method in quantitative analysis of the surficial modification characterization of PSi requiring a small amount of sample.


Asunto(s)
Nanopartículas , Silicio , Aminas , Nanopartículas/química , Polietilenglicoles , Porosidad , Espectroscopía de Protones por Resonancia Magnética , Silicio/química
14.
Nat Commun ; 13(1): 1262, 2022 03 10.
Artículo en Inglés | MEDLINE | ID: mdl-35273148

RESUMEN

Drug delivery systems with high content of drug can minimize excipients administration, reduce side effects, improve therapeutic efficacy and/or promote patient compliance. However, engineering such systems is extremely challenging, as their loading capacity is inherently limited by the compatibility between drug molecules and carrier materials. To mitigate the drug-carrier compatibility limitation towards therapeutics encapsulation, we developed a sequential solidification strategy. In this strategy, the precisely controlled diffusion of solvents from droplets ensures the fast in-droplet precipitation of drug molecules prior to the solidification of polymer materials. After polymer solidification, a mass of drug nanoparticles is embedded in the polymer matrix, forming a nano-in-micro structured microsphere. All the obtained microspheres exhibit long-term storage stability, controlled release of drug molecules, and most importantly, high mass fraction of therapeutics (21.8-63.1 wt%). Benefiting from their high drug loading degree, the nano-in-micro structured acetalated dextran microspheres deliver a high dose of methylprednisolone (400 µg) within the limited administration volume (10 µL) by one single intrathecal injection. The amount of acetalated dextran used was 1/433 of that of low drug-loaded microspheres. Moreover, the controlled release of methylprednisolone from high drug-loaded microspheres contributes to improved therapeutic efficacy and reduced side effects than low drug-loaded microspheres and free drug in spinal cord injury therapy.


Asunto(s)
Polímeros , Traumatismos de la Médula Espinal , Portadores de Fármacos , Sistemas de Liberación de Medicamentos , Humanos , Microesferas , Solventes , Traumatismos de la Médula Espinal/tratamiento farmacológico
15.
Adv Mater ; 34(42): e2203915, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35985348

RESUMEN

As a result of the deficient tumor-specific antigens, potential off-target effect, and influence of protein corona, metal-organic framework nanoparticles have inadequate accumulation in tumor tissues, limiting their therapeutic effects. In this work, a pH-responsive linker (L) is prepared by covalently modifying oleylamine (OA) with 3-(bromomethyl)-4-methyl-2,5-furandione (MMfu) and poly(ethylene glycol) (PEG). Then, the L is embedded into a solid lipid nanoshell to coat apilimod (Ap)-loaded zeolitic imidazolate framework (Ap-ZIF) to form Ap-ZIF@SLN#L. Under the tumor microenvironment, the hydrophilic PEG and MMfu are removed, exposing the hydrophobic OA on Ap-ZIF@SLN#L, increasing their uptake in cancer cells and accumulation in the tumor. The ZIF@SLN#L nanoparticle induces reactive oxygen species (ROS). Ap released from Ap-ZIF@SLN#L significantly promotes intracellular ROS and lactate dehydrogenase generation. Ap-ZIF@SLN#L inhibits tumor growth, increases the survival rate in mice, activates the tumor microenvironment, and improves the infiltration of macrophages and T cells in the tumor, as demonstrated in two different tumor-bearing mice after injections with Ap-ZIF@SLN#TL. Furthermore, mice show normal tissue structure of the main organs and the normal serum level in alanine aminotransferase and aspartate aminotransferase after treatment with the nanoparticles. Overall, this pH-responsive targeting strategy improves nanoparticle accumulation in tumors with enhanced therapeutic effects.


Asunto(s)
Estructuras Metalorgánicas , Nanopartículas , Neoplasias , Corona de Proteínas , Zeolitas , Ratones , Animales , Estructuras Metalorgánicas/química , Especies Reactivas de Oxígeno , Alanina Transaminasa , Anhídridos Maleicos , Nanopartículas/química , Zeolitas/química , Neoplasias/tratamiento farmacológico , Polietilenglicoles/química , Concentración de Iones de Hidrógeno , Aspartato Aminotransferasas , Lactato Deshidrogenasas , Lípidos , Microambiente Tumoral
16.
AAPS PharmSciTech ; 12(4): 1366-73, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22005956

RESUMEN

The purpose of this study was to evaluate the potential of cellulose nanofibers (also referred as microfibrillated cellulose, nanocellulose, nanofibrillated, or nanofibrillar cellulose) as novel tabletting material. For this purpose, physical and mechanical properties of spray-dried cellulose nanofibers (CNF) were examined, and results were compared to those of two commercial grades of microcrystalline cellulose (MCC), Avicel PH101 and Avicel PH102, which are the most commonly and widely used direct compression excipients. Chemically, MCC and CNF are almost identical, but their physical characteristics, like mechanical properties and surface-to-volume ratio, differ remarkably. The novel material was characterized with respect to bulk and tapped as well as true density, moisture content, and flow properties. Tablets made of CNF powder and its mixtures with MCC with or without paracetamol as model compound were produced by direct compression and after wet granulation. The tensile strength of the tablets made in a series of applied pressures was determined, and yield pressure values were calculated from the measurements. With CNF, both wet granulation and direct compression were successful. During tablet compression, CNF particles were less prone to permanent deformation and had less pronounced ductile characteristics. Disintegration and dissolution studies showed slightly faster drug release from direct compression tablets with CNF, while wet granulated systems did not have any significant difference.


Asunto(s)
Acetaminofén/química , Analgésicos no Narcóticos/química , Celulosa/química , Excipientes/química , Nanofibras , Química Farmacéutica , Desecación , Composición de Medicamentos , Cinética , Microscopía Electrónica de Rastreo , Porosidad , Polvos , Presión , Reología , Solubilidad , Propiedades de Superficie , Comprimidos , Tecnología Farmacéutica/métodos , Resistencia a la Tracción , Agua/química
17.
Acta Biomater ; 133: 231-243, 2021 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-33011297

RESUMEN

Nanomedicines represent innovative and promising alternative technologies to improve the therapeutic effects of different drugs for cancer ablation. Targeting M2-like tumor-associated macrophages (TAMs) has emerged as a favorable therapeutic approach to fight against cancer through the modulation of the tumor microenvironment. However, the immunomodulatory molecules used for this purpose present side effects upon systemic administration, which limits their clinical translation. Here, the biocompatible lignin polymer is used to prepare lignin nanoparticles (LNPs) that carry a dual agonist of the toll-like receptors TLR7/8 (resiquimod, R848). These LNPs are targeted to the CD206-positive M2-like TAMs using the "mUNO" peptide, in order to revert their pro-tumor phenotype into anti-tumor M1-like macrophages in the tumor microenvironment of an aggressive triple-negative in vivo model of breast cancer. Overall, we show that targeting the resiquimod (R848)-loaded LNPs to the M2-like macrophages, using very low doses of R848, induces a profound shift in the immune cells in the tumor microenvironment towards an anti-tumor immune state, by increasing the representation of M1-like macrophages, cytotoxic T cells, and activated dendritic cells. This effect consequently enhances the anticancer effect of the vinblastine (Vin) when co-administered with R848-loaded LNPs. STATEMENT OF SIGNIFICANCE: Lignin-based nanoparticles (LNPs) were successfully developed to target a potent TLR7/8 agonist (R848) of the tumor microenvironment (TME). This was achieved by targeting the mannose receptor (CD206) on the tumor supportive (M2-like) macrophages with the "mUNO" peptide, to reprogram them into an anti-tumor (M1-like) phenotype for enhanced chemotherapy. LNPs modified the biodistribution of the R848, and enhanced its accumulation and efficacy in shifting the immunological profile of the cells in the TME, which was not achieved by systemic administration of free R848. Moreover, a reduction in the tumor volumes was observed at lower equivalent doses of R848 compared with other studies. Therefore, the co-administration of R848@LNPs is a promising chemotherapeutic application in aggressive tumors, such as the triple-negative breast cancer.


Asunto(s)
Neoplasias de la Mama , Nanopartículas , Femenino , Humanos , Imidazoles , Lignina , Péptidos , Fenotipo , Distribución Tisular , Microambiente Tumoral , Macrófagos Asociados a Tumores
18.
Int J Pharm ; 590: 119900, 2020 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-32991959

RESUMEN

Nanoprecipitation is a straightforward method for the production of block copolymer nanoparticles for drug delivery applications. However, the effects of process parameters need to be understood to optimize and control the particle size distribution (PSD). To this end, we investigated the effects of material and process factors on PSD and morphology of nanoparticles prepared from an amphiphilic diblock copolymer, poly(ethylene oxide)-block-polycaprolactone. Using a Design of Experiments approach, we explored the joint effects of molecular weight, block length ratios, water volume fraction, stirring rate, polymer concentration and organic phase addition rate on hydrodynamic size and polydispersity index of the nanostructures and created statistical models explaining up to 94% of the variance in hydrodynamic diameter. In addition, we performed morphological characterization by cryogenic transmission electron microscopy and showed that increasing the process temperature may favor the formation of vesicles from these polymers. We showed that the effects of process parameters are dependent on the polymer configuration and we found that the most useful parameters to fine-tune the PSD are the initial polymer concentration and the stirring rate. Overall, this study provides evidence on the joint effects of material and process parameters on PSD and morphology, which will be useful for rational design of formulation-specific optimization studies, scale-up and process controls.


Asunto(s)
Nanoestructuras , Polietilenglicoles , Óxido de Etileno , Tamaño de la Partícula , Poliésteres
19.
ACS Appl Mater Interfaces ; 12(6): 6899-6909, 2020 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-31967771

RESUMEN

Heart tissue engineering is critical in the treatment of myocardial infarction, which may benefit from drug-releasing smart materials. In this study, we load a small molecule (3i-1000) in new biodegradable and conductive patches for application in infarcted myocardium. The composite patches consist of a biocompatible elastomer, poly(glycerol sebacate) (PGS), coupled with collagen type I, used to promote cell attachment. In addition, polypyrrole is incorporated because of its electrical conductivity and to induce cell signaling. Results from the in vitro experiments indicate a high density of cardiac myoblast cells attached on the patches, which stay viable for at least 1 month. The degradation of the patches does not show any cytotoxic effect, while 3i-1000 delivery induces cell proliferation. Conductive patches show high blood wettability and drug release, correlating with the rate of degradation of the PGS matrix. Together with the electrical conductivity and elongation characteristics, the developed biomaterial fits the mechanical, conductive, and biological demands required for cardiac treatment.


Asunto(s)
Decanoatos/química , Sistemas de Liberación de Medicamentos/métodos , Glicerol/análogos & derivados , Infarto del Miocardio/tratamiento farmacológico , Polímeros/química , Bibliotecas de Moléculas Pequeñas/química , Animales , Sistemas de Liberación de Medicamentos/instrumentación , Conductividad Eléctrica , Glicerol/química , Humanos , Ensayo de Materiales , Ratones , Miocitos Cardíacos/citología , Miocitos Cardíacos/efectos de los fármacos , Nanopartículas/química , Pirroles/química , Bibliotecas de Moléculas Pequeñas/farmacología
20.
Nanoscale ; 12(4): 2350-2358, 2020 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-31930241

RESUMEN

The advent of nanomedicine has recently started to innovate the treatment of cardiovascular diseases, in particular myocardial infarction. Although current approaches are very promising, there is still an urgent need for advanced targeting strategies. In this work, the exploitation of macrophage recruitment is proposed as a novel and synergistic approach to improve the addressability of the infarcted myocardium achieved by current peptide-based heart targeting strategies. For this purpose, an acetalated dextran-based nanosystem is designed and successfully functionalized with two different peptides, atrial natriuretic peptide (ANP) and linTT1, which target, respectively, cardiac cells and macrophages associated with atherosclerotic plaques. The biocompatibility of the nanocarrier is screened on both macrophage cell lines and primary macrophages, showing high safety, in particular after functionalization of the nanoparticles' surface. Furthermore, the system shows higher association versus uptake ratio towards M2-like macrophages (approximately 2-fold and 6-fold increase in murine and human primary M2-like macrophages, respectively, compared to M1-like). Overall, the results demonstrate that the nanosystem has potential to exploit the "hitchhike" effect on M2-like macrophages and potentially improve, in a dual targeting strategy, the ability of the ANP peptide to target infarcted heart.


Asunto(s)
Dextranos/química , Macrófagos/metabolismo , Infarto del Miocardio/terapia , Nanomedicina/métodos , Nanopartículas/química , Péptidos/química , Animales , Apoptosis , Factor Natriurético Atrial/química , Materiales Biocompatibles/metabolismo , Línea Celular , Humanos , Concentración de Iones de Hidrógeno , Ratones , Monocitos/metabolismo , Miocardio/metabolismo , Placa Aterosclerótica/metabolismo , Células RAW 264.7
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