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1.
Nanomedicine ; 58: 102749, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38719107

RESUMEN

New adjuvant strategies are needed to improve protein-based subunit vaccine immunogenicity. We examined the potential to use nanostructure of 6-O-ascorbyl palmitate to formulate ovalbumin (OVA) protein and an oligodeoxynucleotide (CpG-ODN) (OCC). In mice immunized with a single dose, OCC elicited an OVA-specific immune response superior to OVA/CpG-ODN solution (OC). Rheological studies demonstrated OCC's self-assembling viscoelastic properties. Biodistribution studies indicated that OCC prolonged OVA and CpG-ODN retention at injection site and lymph nodes, reducing systemic spread. Flow-cytometry assays demonstrated that OCC promoted OVA and CpG-ODN co-uptake by Ly6ChiCD11bhiCD11c+ monocytes. OCC and OC induced early IFN-γ in lymph nodes, but OCC led to higher concentration. Conversely, mice immunized with OC showed higher serum IFN-γ concentration compared to those immunized with OCC. In mice immunized with OCC, NK1.1+ cells were the IFN-γ major producers, and IFN-γ was essential for OVA-specific IgG2c switching. These findings illustrate how this nanostructure improves vaccine's response.


Asunto(s)
Nanoestructuras , Oligodesoxirribonucleótidos , Ovalbúmina , Vacunas de Subunidad , Animales , Nanoestructuras/química , Vacunas de Subunidad/inmunología , Vacunas de Subunidad/química , Vacunas de Subunidad/farmacocinética , Ratones , Oligodesoxirribonucleótidos/química , Oligodesoxirribonucleótidos/farmacocinética , Ovalbúmina/inmunología , Ovalbúmina/química , Femenino , Ratones Endogámicos C57BL , Adyuvantes Inmunológicos/química , Adyuvantes Inmunológicos/farmacocinética , Interferón gamma/metabolismo , Distribución Tisular , Ácido Ascórbico/análogos & derivados
2.
J Am Pharm Assoc (2003) ; 63(5): 1539-1544.e1, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37257695

RESUMEN

BACKGROUND: In response to emergencies, such as wildfires, donations of pharmaceuticals often occur. These donations can be given directly by governments, to non-governmental organizations as corporate donations, or by private entities that donate to individual health institutions. OBJECTIVE: This paper aimed to collect, review and analyze pharmaceutical product donations received during the natural disaster caused by wildfires in the San Luis province, Argentina, in September and October 2020. METHODS: A descriptive, cross-sectional, and retrospective study was performed. An introductory approach to good donation practices was also carried out. Medicines were classified and in the case of products that were not suitable for administration, these were discarded. RESULTS: A total of 15,593 units were segregated, of which 52.8% were over-the-counter products and 47.2% were prescription drugs. 86.3% (13,467 units) were accepted, while 13.7% (2126 units) had to be destroyed. The value of donations totaled USD 16,544. The analysis of the results showed that an important part of the donations was irrelevant in the emergency context. Donations were also received in incorrect amounts, which generated a large stock of medicines that couldn't be used. In emergencies, inappropriate donations create additional work during sorting, storage, and distribution, increasing the time professionals need to complete tasks. This extra work can easily overwhelm limited human and logistical resources. CONCLUSIONS: It is important to previously evaluate the real need for donations. In addition, the distribution of donations must be done through pre-established systems and policies. Otherwise, unsolicited and unnecessary drug donations become wasteful and should therefore be avoided.


Asunto(s)
Desastres Naturales , Medicamentos bajo Prescripción , Humanos , Estudios Transversales , Urgencias Médicas , Estudios Retrospectivos
3.
Drug Dev Ind Pharm ; 49(11): 703-714, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37883065

RESUMEN

OBJECTIVE AND SIGNIFICANCE: This research aims to design and develop a pilot plant-type pharmaceutical reactor with a strong focus on its volumetric capacity and heat transfer capabilities. The primary goal is to replicate design and control strategies at the laboratory or pilot scale to analyze and produce generic semisolid formulations. METHODS: Computational fluid dynamics and heat transfer modeling, utilizing the finite volume method, were employed to determine the reactor's performance and particle trajectory during the mixing and stirring. This allowed for the establishment of optimal operational parameters and variables. Furthermore, prototypes were constructed at 1:2.5 and 1:15 scales to examine the reactor's morphology, ensure volumetric versatility, and conduct mixing, homogenization, and coloration tests using varying volumes. RESULTS AND CONCLUSIONS: The outcomes of this study yielded a versatile reactor suitable for processing pharmaceutical semisolids at both laboratory and pilot-scale volumes. Notably, the reactor demonstrated exceptional volumetric capacity within a single vessel while effectively facilitating heat transfer to its interior.


Asunto(s)
Calor , Composición de Medicamentos/métodos , Preparaciones Farmacéuticas
4.
Pharm Res ; 39(9): 2277-2290, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35851629

RESUMEN

PURPOSE: 3D printing (3DP) makes it possible to obtain systems that are not achievable with current conventional methods, one of them, sustained release floating systems. Floating systems using ricobendazole (RBZ) as a model drug and a combination of polymers were designed and obtained by melt solidification printing technique (MESO-PP). METHODS: Four different MESO-PP inks were formulated based on combinations of the polymers Gelucire 43/01 and Gelucire 50/13 in different ratios. For each of the formulated inks, physicochemical characterization was performed by thermal analysis (thermogravimetric analysis [TGA] and differential scanning calorimetry [DSC]), fourier transform infrared spectrophotometer (FTIR) and X-ray diffraction (XRD). Pharmaceutical characterization was performed by in vitro assays to determine pharmaceutically relevant parameters. These parameters were calculated by applying mathematical models developed to evaluate in vitro drug release profiles. On the other hand, a physiologically based pharmacokinetic (PBPK) model was developed to predict the in vivo performance of RBZ loaded in the different inks by determining the Cmax, and the AUC0-∞. RESULTS: By increasing the proportion of Gelucire 50/13 co-surfactant in the mixtures (the proportion in Ink 1 was 33%, while the proportion in Ink 4 was 80%), the dissolution capacity of RBZ increases substantially, decreasing flotation times. CONCLUSION: MESO-PP produced ink 1 (50% Gelucire 43/01, 25% Gelucire 50/13 and 25% RBZ), which has a zero-order release (RR = 0.180%/min) and the longest flotation time (545 ± 23 min), and in turn would produce a significant increase in oral absorption of the drug, with an AUC0-∞ 2.16-fold higher than that obtained in animals treated with RBZ loaded in conventional tablets.


Asunto(s)
Excipientes , Tinta , Albendazol/análogos & derivados , Animales , Preparaciones de Acción Retardada/química , Excipientes/química , Polímeros , Impresión Tridimensional , Tensoactivos , Comprimidos
5.
Int J Mol Sci ; 23(3)2022 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-35163203

RESUMEN

At present, the use of benzimidazole drugs in veterinary medicine is strongly limited by both pharmacokinetics and formulative issues. In this research, the possibility of applying an innovative semi-solid extrusion 3D printing process in a co-axial configuration was speculated, with the aim of producing a new gastro-retentive dosage form loaded with ricobendazole. To obtain the drug delivery system (DDS), the ionotropic gelation of alginate in combination with a divalent cation during the extrusion was exploited. Two feeds were optimized in accordance with the printing requirements and the drug chemical properties: the crosslinking ink, i.e., a water ethanol mixture containing CaCl2 at two different ratios 0.05 M and 0.1 M, hydroxyethyl cellulose 2% w/v, Tween 85 0.1% v/v and Ricobendazole 5% w/v; and alginate ink, i.e., a sodium alginate solution at 6% w/v. The characterization of the dried DDS obtained from the extrusion of gels containing different amounts of calcium chloride showed a limited effect on the ink extrudability of the crosslinking agent, which on the contrary strongly influenced the final properties of the DDS, with a difference in the polymeric matrix toughness and resulting effects on floating time and drug release.


Asunto(s)
Albendazol/análogos & derivados , Sistemas de Liberación de Medicamentos/métodos , Albendazol/administración & dosificación , Albendazol/farmacología , Alginatos/química , Cloruro de Calcio/química , Composición de Medicamentos/métodos , Sistemas de Liberación de Medicamentos/instrumentación , Sistemas de Liberación de Medicamentos/veterinaria , Liberación de Fármacos , Geles/química , Ácidos Hexurónicos/química , Impresión Tridimensional
6.
Parasitology ; 147(9): 1026-1031, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32338226

RESUMEN

Alveolar echinococcosis is a neglected parasitic zoonosis caused by Echinococcus multilocularis. The pharmacological treatment is based on albendazole (ABZ). However, the low water solubility of the drug produces a limited dissolution rate, with the consequent failure in the treatment of the disease. Solid dispersions are a successful pharmacotechnical strategy to improve the dissolution profile of poorly water-soluble drugs. The aim of this work was to determine the in vivo efficacy of ABZ solid dispersions using poloxamer 407 as a carrier (ABZ:P407 solid dispersions (SDs)) in the murine intraperitoneal infection model for secondary alveolar echinococcosis. In the chemoprophylactic efficacy study, the ABZ suspension, the ABZ:P407 SDs and the physical mixture of ABZ and poloxamer 407 showed a tendency to decrease the development of murine cysts, causing damage to the germinal layer. In the clinical efficacy study, the ABZ:P407 SDs produced a significant decrease in the weight of murine cysts. In addition, the SDs produced extensive damage to the germinal layer. The increase in the efficacy of ABZ could be due to the improvement of water solubility and wettability of the drug due to the surfactant nature of poloxamer 407. In conclusion, this study is the basis for further research. This pharmacotechnical strategy might in the future offer novel treatment alternatives for human alveolar echinococcosis.


Asunto(s)
Albendazol/farmacología , Antiprotozoarios/farmacología , Portadores de Fármacos/farmacología , Equinococosis/prevención & control , Echinococcus multilocularis/efectos de los fármacos , Poloxámero/farmacología , Animales , Femenino , Ratones
7.
AAPS PharmSciTech ; 21(7): 237, 2020 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-32808055

RESUMEN

Valero-fenbendazole (VAL-FBZ) is a novel hybrid compound with in vitro anthelmintic activity, designed and synthesized to address the global problem of resistance to anthelmintic compounds. This new molecule derives from fenbendazole (FBZ), a well-known commercially available benzimidazole used in veterinary medicine despite its poor water solubility. In this work, we report for the first time a strategy to solve the solubility problems of FBZ and VAL-FBZ by means of self-dispersible nanocrystals (SDNC). Nanocrystals were prepared by media milling followed by a spray-drying step, and a comprehensive and exhaustive structural and physicochemical characterization was carried out, in order to understand the systems and their behavior. The formulation poloxamer 188 (P188):FBZ 1:1 turned out with the best process yield (53%) and re-dispersability properties, particle size average of 258 nm, and polydispersity index of 0.2 after redispersion in water. The dissolution profile showed a markedly increased dissolution rate compared with the simple mixture of the components (80% FBZ dissolved in 15 min from the SDNC vs 14% from the control formulation). FTIR spectroscopy, thermal analysis, and X-Ray Powder Diffraction (XRPD) studies showed no chemical interactions between components and an extensive confocal Raman microscopy analysis of the formulations showed very homogeneous spatial distribution of components in the SDNC samples. This manufacturing process was then successfully transferred for preparing and characterizing VAL-FBZ:P188 (1:1) SDNC with similar results, suggesting the promising interest of a novel anthelmintic with improved biopharmaceutical behavior. In conclusion, new FBZ and VAL-FBZ SDNC with improved dissolution rate were successfully prepared and characterized. Graphical abstract.


Asunto(s)
Fenbendazol/química , Lactamas/química , Nanopartículas/química , Desecación , Excipientes/química , Tamaño de la Partícula , Poloxámero/química , Difracción de Polvo , Solubilidad , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Agua/química
8.
Exp Parasitol ; 198: 79-86, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30769018

RESUMEN

Cystic echinococcosis (CE), which is caused during the metacestode larval stage of Echinococcus granulosus, is a life-threatening disease and is very difficult to treat. At present, the FDA-approved antihelmintic drugs are mebendazole (MBZ), albendazole (ABZ) and its principal metabolite ABZ sulfoxide (ABZSO), but as these have a therapeutic efficacy over 50%, underlining the need for new drug delivery systems. The aim of this work was the optimization and characterization of previously developed ABZ lipid nanocapsules (ABZ-LNCs) and evaluate their efficacy in mice infected with E. granulosus. LNCs were prepared by the phase inversion technique and characterized in terms of size, surface charge, drug loading, and in vitro stability followed by an in vivo proof-of-concept using a murine model infected with E. granulosus. Stable particle dispersions with a narrow size distribution and high efficiency of encapsulation (≥90%) were obtained. ABZ-LNCs showed a greater chemoprophylactic efficacy than ABZ suspension administered by the oral route as 4 out of the 10 ABZ-LNCs treated mice did not develop any cysts, whereas the infection progressed in all mice from the ABZ suspension group. Regarding the ultrastructural studies of cysts, mice treated with ABZ-LNCs or ABZ suspension revealed changes in the germinal layer. However, the extent of the damage appeared to be greater after ABZ-LNC administration compared to the suspension treatment. These results suggest that ABZ-LNCs could be a promising novel candidate for ABZ delivery to treat CE.


Asunto(s)
Albendazol/uso terapéutico , Anticestodos/uso terapéutico , Equinococosis/tratamiento farmacológico , Echinococcus granulosus/efectos de los fármacos , Albendazol/administración & dosificación , Albendazol/química , Animales , Anticestodos/administración & dosificación , Anticestodos/química , Bovinos , Cromatografía Líquida de Alta Presión , Equinococosis/prevención & control , Echinococcus granulosus/ultraestructura , Femenino , Intestinos/química , Ratones , Microscopía Electrónica de Rastreo , Nanocápsulas/normas , Nanocápsulas/ultraestructura , Enfermedades Desatendidas/tratamiento farmacológico , Enfermedades Desatendidas/prevención & control , Tamaño de la Partícula , Polvos , Estómago/química
9.
Mol Pharm ; 14(12): 4498-4508, 2017 12 04.
Artículo en Inglés | MEDLINE | ID: mdl-29125768

RESUMEN

This work focuses on improving the effectiveness of current therapies against glaucoma by incorporating self-assembled polymers into the ophthalmic formulation. To that end, we first studied the influence of the dispersing medium on the mechanical performance of self-assembling elastin-like (EL) and silk-elastin-like (SEL) hydrogels by conducting rheological tests. These polymers were subsequently incorporated into the antiglaucoma formulation, which contains timolol maleate (TM) as active ingredient, and in vivo tests, namely adhesion tests and intraocular pressure measurements (IOP), were performed in New Zealand rabbits. An enhanced reduction in IOP due to the presence of the polymers was observed. Moreover, differences in the effectiveness between both EL- and SEL-hydrogels, which can be explained on the basis of the different rheological properties displayed by these two systems, were also encountered. The results point to the potential of this system as a basis for the development of an ophthalmic formulation against glaucoma.


Asunto(s)
Antihipertensivos/uso terapéutico , Portadores de Fármacos/química , Glaucoma/tratamiento farmacológico , Presión Intraocular/efectos de los fármacos , Timolol/uso terapéutico , Animales , Rastreo Diferencial de Calorimetría , Línea Celular , Liberación de Fármacos , Elastina/química , Ojo/efectos de los fármacos , Fibroblastos , Humanos , Hidrogeles/química , Masculino , Modelos Animales , Soluciones Oftálmicas/uso terapéutico , Conejos , Reología , Seda/química , Resultado del Tratamiento
10.
Parasitol Res ; 116(8): 2111-2117, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28523490

RESUMEN

The use of pyrethroids to control the human head louse, Pediculus humanus capitis De Geer (Anoplura: Pediculidae), has suffered considerable loss of efficacy due to the evolution of resistance. Thus, the development of efficiently insecticide delivery systems is imperative for the control of head lice. We studied the insecticidal activity of ivermectin-loaded lipid nanocapsules (IVM-LNC) against permethrin-resistant head lice from Argentina. The LNC, prepared by a phase inversion procedure, were characterized in terms of size, surface potential, and physical stability. These nanoparticles were nearly spherical with mean diameters of 55 nm and narrow size distribution (PI ≤ 0.2). The KT50 mortality values of head lice after exposure to two IVM-LNC formulations (0.11 and 0.28%) were significantly smaller (5 and 3 h, respectively) compared to those exposed only to LNC control group (8 h). This investigation showed the effectiveness in the encapsulation of ivermectin (IVM) into stable LNC dispersion with a potential clinical activity against head lice.


Asunto(s)
Insecticidas/farmacología , Ivermectina/farmacología , Infestaciones por Piojos/tratamiento farmacológico , Pediculus/efectos de los fármacos , Permetrina/farmacología , Animales , Argentina , Composición de Medicamentos , Resistencia a Medicamentos , Humanos , Infestaciones por Piojos/parasitología , Lípidos , Nanopartículas
11.
Pharm Dev Technol ; 22(6): 809-817, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27346432

RESUMEN

The aim of this study was to develop ivermectin (IVM) nanosuspensions (NSs) to improve the dissolution rate of this poorly water-soluble drug. Different NSs combining different stabilizers, i.e. poloxamer 188 (P188), polysorbate 80 (T80), polyvinylpyrrolidone (PVP), and sodium lauryl sulfate (SLS), were prepared by high-pressure homogenization. The stabilizers were selected based on the saturation solubility and IVM stability within 72 h. The screening of formulations was performed by considering the drug content within the nanosize range. The best formulation (IVM:T80:PVP 1:0.5:0.5 wt%) was characterized in terms of the particle size distribution, morphology, crystallinity, drug content, and in vitro dissolution profile. This NS was also evaluated from a stability point of view, by conditioning samples at a constant temperature and relative humidity for six months. The fresh and conditioned best NSs Z-sizes were 174.6 and 215.7 nm, respectively; while both NSs showed low polydispersity indexes. The faster dissolution rate for the IVM NS was attributed to the presence of nanoparticles and changes to the crystal structure (i.e. amorphization) that further improved solubility. The best NS had a 4-fold faster initial dissolution rate than raw IVM, and is thus a promising formulation for the treatment of human and animal parasitic diseases.


Asunto(s)
Ivermectina , Animales , Química Farmacéutica , Composición de Medicamentos , Diseño de Fármacos , Humanos , Nanopartículas , Tamaño de la Partícula , Poloxámero , Solubilidad
12.
Drug Dev Ind Pharm ; 42(10): 1564-70, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26856301

RESUMEN

Albendazole (ABZ) is a broad-spectrum antiparasitic drug used in the treatment of human or animal infections. Although ABZ has shown a high efficacy for repeated doses in monogastric mammals, its low aqueous solubility leads to erratic bioavailability. The aim of this work was to optimize a procedure in order to obtain ABZ self-dispersible nanocrystals (SDNC) by combining high pressure homogenization (HPH) and spray-drying (SD). The material thus obtained was characterized and the variables affecting both the HPH and SD processes were studied. As expected, the homogenizing pressure and number of cycles influenced the final particle size, while the stabilizer concentration had a strong impact on SD output and redispersion of powders upon contact with water. ABZ SDNC were successfully obtained with high process yield and redispersibility. The characteristic peaks of ABZ were clearly identified in the X-ray patterns of the processed samples. A noticeable increase in the dissolution rate was observed in the aqueous environment.


Asunto(s)
Albendazol/química , Nanopartículas/química , Disponibilidad Biológica , Desecación , Liberación de Fármacos , Excipientes/química , Tamaño de la Partícula , Polvos/química , Presión , Solubilidad
13.
Graefes Arch Clin Exp Ophthalmol ; 253(11): 1859-65, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25491161

RESUMEN

PURPOSE: To explore decline in visual acuity in patients with neovascular age-related macular degeneration (n-AMD) awaiting intravitreal bevacizumab or ranibizumab treatment following initial diagnosis and after disease reactivation. METHODS: Retrospective analysis of 74 treatment-naïve patients (84 eyes) in two centers in Córdoba, Argentina. The time between treatment indication and intravitreal injection, and the changes in BCVA produced during this delay were studied in both periods. A linear regression model to search the impact of time on progression visual impairment was conducted. RESULTS: In both periods, a significant reduction in vision occurred awaiting intravitreal injection. The longer the delay, the greater the vision loss (R2 = 0.55 p < 0.01) and the less improvement following treatment (Pearson coefficient -0.26). The result of the model shows that the change in vision as a function of initial delay were best described by a polynomic model with a mean loss of 5 letters in the first 3 weeks, a slowdown in the rate of change of VA, and a dependence of visual acuity at the moment of diagnosis . The loss of visual acuity after reactivation shows the same behavior as at the onset of the disease but independent of visual acuity prior to reactivation. CONCLUSION: Visual loss awaiting injection intravitreal anti-VEGF is clinically significant and with an asymptotic pattern, with early rapid loss of vision in both the onset of the disease and the reactivation. Initiation of anti-VEGF treatment must be undertaken urgently, as should retreatment of disease activation to reduce visual loss.


Asunto(s)
Trastornos de la Visión/fisiopatología , Agudeza Visual/fisiología , Degeneración Macular Húmeda/fisiopatología , Anciano , Anciano de 80 o más Años , Inhibidores de la Angiogénesis/uso terapéutico , Bevacizumab/uso terapéutico , Femenino , Humanos , Inyecciones Intravítreas , Masculino , Persona de Mediana Edad , Ranibizumab/uso terapéutico , Estudios Retrospectivos , Tomografía de Coherencia Óptica , Factor A de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Espera Vigilante , Degeneración Macular Húmeda/diagnóstico , Degeneración Macular Húmeda/tratamiento farmacológico
14.
Mol Membr Biol ; 31(2-3): 85-94, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24650150

RESUMEN

Amiodarone (AMI) is a low water-solubility drug, which is very useful in the treatment of severe cardiac disease. Its adverse effects are associated with toxicity in different tissues. Several antioxidants have been shown to reduce, and prevent AMI toxicity. The aim of this work was to develop and characterize Dimyristoylphosphatidylcholine (DMPC) liposomal carriers doped with ascorbyl palmitate (Asc16) as antioxidant, in order to either minimize or avoid the adverse effects produced by AMI. The employment of liposomes would avoid the use of cosolvents in AMI formulations, and Asc16 could minimize the adverse effects of AMI. To evaluate the partition and integration of AMI and Asc16 in lipid membranes, penetration studies into DMPC monolayers were carried out. The disturbance of the liposomes membranes was studied by generalized polarization (GP). The stability of liposomes was evaluated experimentally and by means of the Derjaguin-Landau-Verwey-Overbeek (DLVO) theory. The size particle and zeta potential (ζ) values of the liposomes were used for application in calculations for attractive and repulsive forces in DLVO theory. In experimental conditions all of these vesicles showed stability at time 0, but only DMPC + Asc16 10% + AMI 10% liposomes kept their size stable and ζ during 28 days. These results are encouraging and suggest that such systems could be suitable for AMI delivery formulations.


Asunto(s)
Amiodarona/química , Antioxidantes/farmacocinética , Ácido Ascórbico/análogos & derivados , Dimiristoilfosfatidilcolina/análisis , Liposomas Unilamelares/análisis , Antioxidantes/química , Ácido Ascórbico/química , Ácido Ascórbico/farmacocinética , Fenómenos Químicos , Estabilidad de Medicamentos , Tamaño de la Partícula , Solubilidad , Liposomas Unilamelares/química
15.
J Nanosci Nanotechnol ; 14(5): 3343-7, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24734550

RESUMEN

New magnetic devices consisting of magnetite functionalized with oleic acid and chitosan have been synthesized and employed to the loading of Diclofenac as potential tool for treatment of targeted inflammatory diseases. Magnetic loaded and un-loaded nanoparticles have been thoroughly characterized by infrared spectroscopy, transmission electron microscopy, determination of hydrodynamic diameter by Dynamic light scattering and zeta potential measurements at different pH conditions. A study of the release of Diclofenac has been performed in vitro and available mathematical models have been used to determine the release kinetic. Both properties and release data reveal that this nanomagnetic platform would be suitable for in vivo assays.


Asunto(s)
Antiinflamatorios no Esteroideos/administración & dosificación , Quitosano/química , Diclofenaco/administración & dosificación , Magnetismo , Nanopartículas , Antiinflamatorios no Esteroideos/química , Antiinflamatorios no Esteroideos/farmacocinética , Diclofenaco/química , Diclofenaco/farmacocinética , Sistemas de Liberación de Medicamentos , Microscopía Electrónica de Transmisión , Espectrofotometría Infrarroja
16.
Parasitol Res ; 113(2): 793-800, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24292544

RESUMEN

Microemulsions (ME) are thermodynamically stable isotropic mixtures of oil, water, and surfactant; they would also be attractive as potential insecticidal products due to the high bioviability of the active ingredient, attributable to the small sizes of the oil drops. A laboratory study was conducted in order to compare the biological effect of oil in water (o/w) geranium essential oil (EO) and geraniol MEs and emulsions, against Culex pipiens pipiens mosquito larvae. The systems were based on three nonionic surfactants (Cremophor EL, Brij 35, Tween 80). The MEs showed dispersed phase diameters in the range of 8 to 14 nm and had low PDI values (<0.2). The MEs were analyzed by TEM, indicating that they had nearly spherical morphology. The microemulsified systems based on geranium EO and those of geraniol produced a notable increase of the larvicidal activity when compared with the respectably emulsions, concluding that the biological effect is related with the diameter of the dispersed phase. The smallest drops achieved the highest larvicidal activity, being the aqueous nanoformulations based on geraniol most effective than those of geranium EO. However, geranium microemulsions are preferred due to their residual toxicological profiles. The results indicate that these novel systems could be used in integrated pest management program for the C. pipiens pipiens.


Asunto(s)
Culex , Geranium/química , Insecticidas , Control de Mosquitos , Aceites Volátiles , Terpenos , Monoterpenos Acíclicos , Animales , Culex/crecimiento & desarrollo , Emulsiones , Larva , Dosificación Letal Mediana , Tamaño de la Partícula , Polietilenglicoles , Polisorbatos , Tensoactivos , Agua
17.
Drug Deliv Transl Res ; 14(5): 1301-1318, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-37953429

RESUMEN

The challenge of low water solubility in pharmaceutical science profoundly impacts drug absorption and therapeutic effectiveness. Nanocrystals (NC), consisting of drug molecules and stabilizing agents, offer a promising solution to enhance solubility and control release rates. In the pharmaceutical industry, top-down techniques are favored for their flexibility and cost-effectiveness. However, increased solubility can lead to premature drug dissolution in the stomach, which is problematic due to the acidic pH or enzymes. Researchers are exploring encapsulating agents that facilitate drug release at customized pH levels as a valuable strategy to address this. This study employed wet milling and spray drying techniques to create encapsulated NC for delivering the drug to the intestinal tract using the model drug ivermectin (IVM). Nanosuspensions (NS) were efficiently produced within 2 h using NanoDisp®, with a particle size of 198.4 ± 0.6 nm and a low polydispersity index (PDI) of 0.184, ensuring uniformity. Stability tests over 100 days at 4 °C and 25 °C demonstrated practical viability, with no precipitation or significant changes observed. Cytotoxicity evaluations indicated less harm to Caco-2 cells compared to the pure drug. Furthermore, the solubility of the NC increased by 47-fold in water and 4.8-fold in simulated intestinal fluid compared to the pure active compound. Finally, dissolution tests showed less than 10% release in acidic conditions and significant improvement in simulated intestinal conditions, promising enhanced drug solubility and bioavailability. This addresses a long-standing pharmaceutical challenge in a cost-effective and scalable manner.


Asunto(s)
Química Farmacéutica , Nanopartículas , Humanos , Química Farmacéutica/métodos , Células CACO-2 , Preparaciones Farmacéuticas/química , Solubilidad , Disponibilidad Biológica , Nanopartículas/química , Agua , Concentración de Iones de Hidrógeno , Tamaño de la Partícula
18.
Int J Pharm ; 650: 123720, 2024 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-38110014

RESUMEN

Atorvastatin (ATV) is a first-line drug for the treatment of hyperlipidemia. This drug presents biopharmaceutical problems, partly due to its low solubility and dissolution rate. In this work, nanocrystals of ATV stabilized with Tween 80® were designed by wet milling. A full factorial design was applied to optimize the process. Additionally, a cryoprotectant agent (maltodextrin, MTX) was identified, which allowed maintaining the properties of the nanocrystals after lyophilization. The storage stability of the nanocrystals was demonstrated for six months in different conditions. The obtained nanocrystal powder was characterized using SEM, EDXS, TEM, DSC, TGA, FT-IR, and XRD, showing the presence of irregular crystals with semi-amorphous characteristics, likely due to the particle collision process. Based on the reduction in particle size and the decrease in drug crystallinity, a significant increase in water and phosphate buffer (pH 6.8) solubility by 4 and 6 times, respectively, was observed. On the other hand, a noticeable increase in the dissolution rate was observed, with 90 % of the drug dissolved within 60 min of study, compared to 30 % of the drug dissolved within 12 h in the case of the untreated drug or the physical mixture of components. Based on these results, it can be concluded that the nano-milling of Atorvastatin stabilized with Tween 80® is a promising strategy for developing new formulations with improved biopharmaceutical properties of this widely used drug.


Asunto(s)
Productos Biológicos , Nanopartículas , Polisorbatos , Atorvastatina/química , Espectroscopía Infrarroja por Transformada de Fourier , Solubilidad , Nanopartículas/química , Liofilización , Tamaño de la Partícula
19.
Acta Trop ; 257: 107285, 2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38908420

RESUMEN

Cystic echinococcosis is a zoonotic infection caused by the larval stage of Echinococcus granulosus sensu lato. The disease is characterized by the long-term growth of cysts, most commonly in the liver and lungs. Although an ideal model of cystic echinococcosis should induce the development of cysts in the liver and imitate the natural infection route, the murine model of intraperitoneal is still widely used in the field of experimental theraphy. The aim of the present work was to evaluate the usefulness of the murine model of hepatic CE for preclinical drug trials. The effectiveness of albendazole could also be assessed by measuring the diameter of the hepatic cyst. The albendazole significantly reduced the size of the cysts. The ultrastructural alterations of the germinal layer of hepatic cysts provoked by albendazole coincided with those observed in the intraperitoneal model. Similar results were obtained with both albendazole doses. Therefore, the efficacy of albendazole nanocrystals in the murine model of hepatic cystic echinococcosis was carried out at albendazole doses of 25 mg/kg. The abdominal ultrasound allows us to assess the response of cysts to drugs only in a qualitative manner. Although the size of cysts in the albendazole nanocrystal group was not significantly lower than that observed with albendazole, at the ultrastructural level, a greater extent of damage was observed. The murine model of hepatic cystic echinococcosis can be effectively used for assessing the effect of novel formulations or compounds. The main advantage of this model is that cysts are located in the orthotopic organ, which resembles the location most commonly found in human cases. In future studies, the usefulness of the model for pharmacokinetics studies in hepatic cysts will be evaluated.

20.
Int J Pharm ; 657: 124098, 2024 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-38621614

RESUMEN

Glaucoma, the second most common cause of blindness worldwide, requires the development of new and effective treatments. This study introduces a novel controlled-release system utilizing elastin-like recombinamers (ELR) and the Supercritical Antisolvent (SAS) technique with supercritical CO2. Acetazolamide (AZM), a class IV drug with limited solubility and permeability, is successfully encapsulated in an amphiphilic ELR at three different ELR:AZM ratios, yielding up to 62 %. Scanning electron microscopy (SEM) reveals spherical microparticles that disintegrate into monodisperse nanoparticles measuring approximately 42 nm under physiological conditions. The nanoparticles, as observed via Transmission Electron Microscopy (TEM) and Atomic Force Microscopy (AFM), do not exhibit aggregates, a fact confirmed by the zeta potential displaying a value of -33 mV over a period of 30 days. Transcorneal permeation tests demonstrate a 10 % higher permeation level compared to the control solution, which increases to 30 % after 2 h. Ocular irritation tests demonstrate no adverse effects or damage. Intraocular pressure (IOP) tests conducted on hypertensive rabbits indicate greater effectiveness for all three analyzed formulations, suggesting enhanced drug bioavailability during treatment. Consequently, the combination of recombinant biopolymers and high-pressure techniques represents a promising approach for advancing glaucoma therapy, emphasizing its potential clinical significance.


Asunto(s)
Acetazolamida , Elastina , Glaucoma , Presión Intraocular , Nanopartículas , Conejos , Animales , Acetazolamida/administración & dosificación , Acetazolamida/química , Acetazolamida/farmacocinética , Glaucoma/tratamiento farmacológico , Elastina/química , Presión Intraocular/efectos de los fármacos , Nanopartículas/química , Preparaciones de Acción Retardada/química , Solventes/química , Solubilidad , Masculino , Inhibidores de Anhidrasa Carbónica/administración & dosificación , Inhibidores de Anhidrasa Carbónica/química , Inhibidores de Anhidrasa Carbónica/farmacocinética , Disponibilidad Biológica , Córnea/metabolismo , Córnea/efectos de los fármacos , Composición de Medicamentos/métodos , Permeabilidad
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