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1.
Mater Today Bio ; 26: 101088, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38779556

RESUMO

Osteogenic-osteoclast coupling processes play a crucial role in bone regeneration. Recently, strategies that focus on multi-functionalized implant surfaces to enhance the healing of bone defects through the synergistic regulation of osteogenesis and osteoclastogenesis is still a challenging task in the field of bone tissue engineering. The aim of this study was to create a dual-drug release-based core-shell nanofibers with the intent of achieving a time-controlled release to facilitate bone regeneration. We fabricated core-shell P/PCL nanofibers using coaxial electrospinning, where alendronate (ALN) was incorporated into the core layer and hydroxyapatite (HA) into shell. The surface of the nanofiber construct was further modified with mussel-derived polydopamine (PDA) to induce hydrophilicity and enhance cell interactions. Surface characterizations confirmed the successful synthesis of PDA@PHA/PCL-ALN nanofibers endowed with excellent mechanical strength (20.02 ± 0.13 MPa) and hydrophilicity (22.56°), as well as the sustained sequential release of ALN and Ca ions. In vitro experiments demonstrated that PDA-functionalized core-shell PHA/PCL-ALN scaffolds possessed excellent cytocompatibility, enhanced cell adhesion and proliferation, alkaline phosphatase activity and osteogenesis-related genes. In addition to osteogenesis, the engineered scaffolds also significantly reduced osteoclastogenesis, such as tartrate-resistant acid phosphatase activity and osteoclastogenesis-related gene expression. After 12-week of implantation, it was observed that PDA@PHA/PCL-ALN nanofiber scaffolds, in a rat cranial defect model, significantly promoted bone repair and regeneration. Microcomputed tomography, histological examination, and immunohistochemical analysis collectively demonstrated that the PDA-functionalized core-shell PHA/PCL-ALN scaffolds exhibited exceptional osteogenesis-inducing and osteoclastogenesis-inhibiting effects. Finally, it may be concluded from our results that the bio-inspired surface-functionalized multifunctional, biomimetic and controlled release core-shell nanofiber provides a promising strategy to facilitate bone healing.

2.
Int J Biol Macromol ; 260(Pt 1): 129416, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38224810

RESUMO

Zein, a protein-based biopolymer derived from corn, has garnered attention as a promising and eco-friendly choice for packaging food due to its favorable physical attributes. The introduction of electrospinning technology has significantly advanced the production of zein-based nanomaterials. This cutting-edge technique enables the creation of nanofibers with customizable structures, offering high surface area and adjustable mechanical and thermal attributes. Moreover, the electrospinning process allows for integrating various additives, such as antioxidants, antimicrobial agents, and flavoring compounds, into the zein nanofibers, enhancing their functionalities for food preservation. In this comprehensive review, the various electrospinning techniques employed for crafting zein-based nanofibers, and we delve into their enhanced properties. Furthermore, the review illuminates the potential applications of zein nanofibers in active and intelligent packaging materials by incorporating diverse constituents. Altogether, this review highlights the considerable prospects of zein-based nanocomposites in the realm of food packaging, offering sustainable and innovative solutions for food industry.


Assuntos
Nanocompostos , Nanofibras , Zeína , Nanofibras/química , Embalagem de Alimentos , Zeína/química , Nanotecnologia/métodos
3.
Int J Biol Macromol ; 256(Pt 2): 128452, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38042321

RESUMO

Cancer is a devastating disease that causes a substantial number of deaths worldwide. Current therapeutic interventions for cancer include chemotherapy, radiation therapy, or surgery. These conventional therapeutic approaches are associated with disadvantages such as multidrug resistance, destruction of healthy tissues, and tissue toxicity. Therefore, there is a paradigm shift in cancer management wherein nanomedicine-based novel therapeutic interventions are being explored to overcome the aforementioned disadvantages. Supramolecular self-assembled peptide nanofibers are emerging drug delivery vehicles that have gained much attention in cancer management owing to their biocompatibility, biodegradability, biomimetic property, stimuli-responsiveness, transformability, and inherent therapeutic property. Supramolecules form well-organized structures via non-covalent linkages, the intricate molecular arrangement helps to improve tissue permeation, pharmacokinetic profile and chemical stability of therapeutic agents while enabling targeted delivery and allowing efficient tumor imaging. In this review, we present fundamental aspects of peptide-based self-assembled nanofiber fabrication their applications in monotherapy/combinatorial chemo- and/or immuno-therapy to overcome multi-drug resistance. The role of self-assembled structures in targeted/stimuli-responsive (pH, enzyme and photo-responsive) drug delivery has been discussed along with the case studies. Further, recent advancements in peptide nanofibers in cancer diagnosis, imaging, gene therapy, and immune therapy along with regulatory obstacles towards clinical translation have been deliberated.


Assuntos
Nanofibras , Neoplasias , Humanos , Nanofibras/química , Peptídeos/química , Sistemas de Liberação de Medicamentos/métodos , Neoplasias/tratamento farmacológico , Imunidade Celular
4.
Int J Nanomedicine ; 18: 7021-7046, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38046236

RESUMO

Background: Antitumor research aims to efficiently target hepatocarcinoma cells (HCC) for drug delivery. Nanostructured lipid carriers (NLCs) are promising for active tumour targeting. Cell-penetrating peptides are feasible ligands for targeted cancer treatment. Methods: In this study, we optimized gefitinib-loaded NLCs (GF-NLC) for HCC treatment. The NLCs contained cholesterol, oleic acid, Pluronic F-68, and Phospholipon 90G. The NLC surface was functionalized to enhance targeting with the cRGDfK-pentapeptide, which binds to the αvß3 integrin receptor overexpressed on hepatocarcinoma cells. Results: GF-NLC formulation was thoroughly characterized for various parameters using differential scanning calorimetry and X-ray diffraction analysis. In-vitro and in-vivo studies on the HepG2 cell line showed cRGDfK@GF-NLC's superiority over GF-NLC and free gefitinib. cRGDfK@GF-NLC exhibited significantly higher cytotoxicity, growth inhibition, and cellular internalization. Biodistribution studies demonstrated enhanced tumour site accumulation without organ toxicity. The findings highlight cRGDfK@GF-NLC as a highly efficient carrier for targeted drug delivery, surpassing non-functionalized NLCs. These functionalized NLCs offer promising prospects for improving hepatocarcinoma therapy outcomes by specifically targeting HCC cells. Conclusion: Based on these findings, cRGDfK@GF-NLC holds immense potential as a highly efficient carrier for targeted drug delivery of anticancer agents, surpassing the capabilities of non-functionalized NLCs. This research opens up new avenues for effective treatment strategies in hepatocarcinoma.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Nanoestruturas , Humanos , Portadores de Fármacos/química , Carcinoma Hepatocelular/tratamento farmacológico , Gefitinibe , Distribuição Tecidual , Neoplasias Hepáticas/tratamento farmacológico , Nanoestruturas/química , Tamanho da Partícula , Lipídeos/química
5.
Front Bioeng Biotechnol ; 11: 1302594, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38026845

RESUMO

Electrospun composite nanofiber scaffolds are well known for their bone and tissue regeneration applications. This research is focused on the development of PVP and PVA nanofiber composite scaffolds enriched with hydroxyapatite (HA) nanoparticles and alendronate (ALN) using the electrospinning technique. The developed nanofiber scaffolds were investigated for their physicochemical as well as bone regeneration potential. The results obtained from particle size, zeta potential, SEM and EDX analysis of HA nanoparticles confirmed their successful fabrication. Further, SEM analysis verified nanofiber's diameters within 200-250 nm, while EDX analysis confirmed the successful incorporation of HA and ALN into the scaffolds. XRD and TGA analysis revealed the amorphous and thermally stable nature of the nanofiber composite scaffolds. Contact angle, FTIR analysis, Swelling and biodegradability studies revealed the hydrophilicity, chemical compatibility, suitable water uptake capacity and increased in-vitro degradation making it appropriate for tissue regeneration. The addition of HA into nanofiber scaffolds enhanced the physiochemical properties. Additionally, hemolysis cell viability, cell adhesion and proliferation by SEM as well as confocal microscopy and live/dead assay results demonstrated the non-toxic and biocompatibility behavior of nanofiber scaffolds. Alkaline phosphatase (ALP) and tartrate-resistant acid phosphatase (TRAP) assays demonstrated osteoblast promotion and osteoclast inhibition, respectively. These findings suggest that developed HA and ALN-loaded PVP/PVA-ALN-HA nanofiber composite scaffolds hold significant promise for bone regeneration applications.

6.
Front Bioeng Biotechnol ; 11: 1288539, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38026878

RESUMO

Electrospinning is a versatile method for fabrication of précised nanofibrous materials for various biomedical application including tissue engineering and drug delivery. This research is aimed to fabricate the PVP/PVA nanofiber scaffold by novel electrospinning technique and to investigate the impact of process parameters (flow rate, voltage and distance) and polymer concentration/solvent combinations influence on properties of electrospun nanofibers. The in-vitro and in-vivo degradation studies were performed to evaluate the potential of electrospun PVP/PVA as a tissue engineering scaffold. The solvents used for electrospinning of PVP/PVA nanofibers were ethanol and 90% acetic acid, optimized with central composite design via Design Expert software. NF-2 and NF-35 were selected as optimised nanofiber formulation in acetic acid and ethanol, and their characterization showed diameter of 150-400 nm, tensile strength of 18.3 and 13.1 MPa, respectively. XRD data revealed the amorphous nature, and exhibited hydrophilicity (contact angles: 67.89° and 58.31° for NF-2 and NF-35). Swelling and in-vitro degradability studies displayed extended water retention as well as delayed degradation. FTIR analysis confirmed solvent-independent interactions. Additionally, hemolysis and in-vitro cytotoxicity studies revealed the non-toxic nature of fabricated scaffolds on RBCs and L929 fibroblast cells. Subcutaneous rat implantation assessed tissue response, month-long biodegradation, and biocompatibility through histological analysis of surrounding tissue. Due to its excellent biocompatibility, this porous PVP/PVA nanofiber has great potential for biomedical applications.

7.
Artigo em Inglês | MEDLINE | ID: mdl-37519201

RESUMO

All over the world, cancer death and prevalence are increasing. Breast cancer (BC) is the major cause of cancer mortality (15%) which makes it the most common cancer in women. BC is defined as the furious progression and quick division of breast cells. Novel nanotechnology-based approaches helped in improving survival rate, metastatic BC is still facing obstacles to treat with an expected overall 23% survival rate. This paper represents epidemiology, classification (non-invasive, invasive and metastatic), risk factors (genetic and non-genetic) and treatment challenges of breast cancer in brief. This review paper focus on the importance of nanotechnology-based nanoformulations for treatment of BC. This review aims to deliver elementary insight and understanding of the novel nanoformulations in BC treatment and to explain to the readers for enduring designing novel nanomedicine. Later, we elaborate on several types of nanoformulations used in tumor therapeutics such as liposomes, dendrimers, polymeric nanomaterials and many others. Potential research opportunities for clinical application and current challenges related to nanoformulations utility for the treatment of BC are also highlighted in this review. The role of artificial intelligence is elaborated in detail. We also confer the existing challenges and perspectives of nanoformulations in effective tumor management, with emphasis on the various patented nanoformulations approved or progression of clinical trials retrieved from various search engines.

8.
Int J Pharm ; 638: 122918, 2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-37030638

RESUMO

Electrospun nanofibers scaffolds show promising potential in wound healing applications. This work aims to fabricate nanofibrous wound dressing as a novel approach for a topical drug delivery system. Herein, the electrospinning technique is used to design and fabricate bioabsorbable nanofibrous scaffolds of Polyvinyl alcohol/gelatin/poly (lactic-co-glycolic acid) enriched with thrombin (TMB) as hemostatic agent and vancomycin (VCM) as anti-bacterial agent for a multifunctional platform to control excessive blood loss, inhibit bacterial growth and enhance wound healing. SEM, FTIR, XRD, in vitro drug release, antimicrobial studies, biofilm, cell viability assay, and in vivo study in a rat model were used to assess nanofiber's structural, mechanical, and biological aspects. SEM images confirms the diameter of nanofibers which falls within the range from 150 to 300 nm for all the batches. Excellent swelling index data makes it suitable to absorb wound exudates. In-vitro drug release data shows sustained release behavior of nanofiber. Nanofibers scaffolds showed biomimetic behavior and excellent biocompatibility. Moreover, scaffolds exhibited excellent antimicrobial and biofilm activity against Staphylococcus aureus. Nanofibrous scaffolds showed less bleeding time, rapid blood coagulation, and excellent wound closure in a rat model. ELISA study demonstrated the decreasing level of inflammatory markers, such as TNF-α, IL1ß, and IL-6, making formulation promising for hemostatic wound healing applications. Finally, the study concludes that nanofibrous scaffolds loaded with TMB and VCM have promising potential as a dressing material for hemostatic wound healing applications.


Assuntos
Anti-Infecciosos , Hemostáticos , Nanofibras , Ratos , Animais , Antibacterianos , Gelatina/química , Nanofibras/química , Álcool de Polivinil/química , Hemostáticos/farmacologia , Glicóis , Cicatrização
9.
Front Pharmacol ; 13: 1021867, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36386226

RESUMO

Hepatocellular carcinoma (HCC) is a common malignancy which affects a substantial number of individuals all over the globe. It is the third primary cause of death among persons with neoplasm and has the fifth largest mortality rate among men and the seventh highest mortality rate among women. Dalbergin (DL) is described to be effective in breast cancer via changing mRNA levels of apoptosis-related proteins. DL belongs to neoflavonoids, a drug category with low solubility and poor bioavailability. We created a synthetic version of this naturally occurring chemical, DL, and then analyzed it using 1H-NMR, 13C-NMR, and LC-MS. We also made PLGA nanoparticles and then coated them with galactose. The design of experiment software was used to optimize DL-loaded galactose-modified PLGA nanoparticles. The optimized DL-nanoformulations (DLF) and DL-modified nanoformulations (DLMF) were analyzed for particle size, polydispersity index, shape, and potential interactions. In-vitro experiments on liver cancer cell lines (HepG2) are used to validate the anti-proliferative efficacy of the modified DLMF. The in-vitro research on HepG2 cell lines also demonstrated cellular accumulation of DLF and DLMF by FITC level. The in-vitro result suggested that DLMF has high therapeutic effectiveness against HCC. In-vivo pharmacokinetics and bio-distribution experiments revealed that DLMF excelled pristine DL in terms of pharmacokinetic performance and targeted delivery, which is related to galactose's targeting activity on the asialoglycoprotein receptor (ASGPR) in hepatic cells. Additionally, we performed an in-silico study of DL on caspase 3 and 9 proteins, and the results were found to be -6.7 kcal/mol and -6.6 kcal/mol, respectively. Our in-silico analysis revealed that the DL had strong apoptotic properties against HCC.

10.
Drug Discov Today ; 27(9): 2526-2540, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35753642

RESUMO

Breast cancer (BC) is the second most common cancer in women, with a high morbidity rate. The human epidermal growth factor receptor HER2 is a growth-promoting protein that is overexpressed in 15-20% of breast cancers (HER2+ BCs) and is often associated with clinically aggressive disease. Targeting this oncogene has resulted in significant improvements in survival outcomes for HER2+ BC patients. Several HER2-targeted therapies are currently available, including monoclonal antibodies, tyrosine kinase inhibitors, and antibody-drug conjugates. These therapeutics have improved clinical outcomes in HER2+ BC patients with metastatic disease, increasing the median overall survival (OS) rate. Despite these advancements, there are still many challenges to overcome. In recent times, there has been a significant increase in the use of engineered nanomaterials as efficient cancer therapeutics. In this review, we summarize the application of nanomaterials in HER2+ BC therapy using selected examples.


Assuntos
Neoplasias da Mama , Nanoestruturas , Feminino , Humanos , Terapia de Alvo Molecular , Receptor ErbB-2
11.
Curr Drug Deliv ; 2021 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-33655835

RESUMO

The article has been withdrawn at the request of the editor of the journal Current Drug Delivery due to incoherent content.Bentham Science apologizes to the readers of the journal for any inconvenience this may have caused.The Bentham Editorial Policy on Article Withdrawal can be found at https://benthamscience.com/editorial-policies-main.php Bentham Science Disclaimer: It is a condition of publication that manuscripts submitted to this journal have not been published and will not be simultaneously submitted or published elsewhere. Furthermore, any data, illustration, structure or table that has been published elsewhere must be reported, and copyright permission for reproduction must be obtained. Plagiarism is strictly forbidden, and by submit- ting the article for publication the authors agree that the publishers have the legal right to take appropriate action against the authors, if plagiarism or fabricated information is discovered. By submitting a manuscript, the authors agree that the copyright of their article is transferred to the publishers if and when the article is accepted for publication.

12.
Int J Biol Macromol ; 176: 376-386, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33561460

RESUMO

Electrospinning is emerging as a versatile technique nanofibers fabrication because due to their unique properties such as large surface area to volume ratio, porosity and maintaining moist wound environment, the nanofibers are able to deliver sustained drug release and oxygen to the wound for rapid healing of diabetic wound. The present work was aimed to prepare and evaluate silk fibroin-curcumin based nanofiber in combination with polycaprolactone (PCL) and polyvinyl alcohol (PVA) which helped to strengthen the wound healing properties of nanofiber. Silk fibroin is a naturally occurring polymer was selected one polymer for making nanofibrous mat due to its unique properties such as biodegradability, permeability, oxygen supply and maintain moisture content in the wound. SEM results showed diameters of fibers varied in the range between 200 and 350 nm and their tensile strength ranged from 12.41 to 16.80 MP. The nanofibers were causing sustained release of curcumin for many hours. The in-vivo wound healing studies in streptozotocin-induced diabetic mice showed rapid wound healing efficacy as compared to conventional formulations. Furthermore, the histopathological studies evidenced its ability to restore the normal skin structure and histological conditions of tissues. The silk fibroin-based nanofiber wound dressing, therefore appears to be an ideal preparation, in combination with curcumin, because it blends the anti-oxidant, anti-inflammatory properties of curcumin. Therefore, it was concluded that the silk fibroin-based nanofiber loaded with curcumin has great healing potential in diabetic wound.


Assuntos
Bandagens , Curcumina , Angiopatias Diabéticas , Fibroínas/química , Nanofibras/química , Poliésteres/química , Álcool de Polivinil/química , Cicatrização/efeitos dos fármacos , Animais , Curcumina/química , Curcumina/farmacocinética , Curcumina/farmacologia , Angiopatias Diabéticas/tratamento farmacológico , Angiopatias Diabéticas/metabolismo , Angiopatias Diabéticas/patologia , Feminino , Camundongos
13.
Front Pharmacol ; 12: 823285, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35095533

RESUMO

Hepatocellular carcinoma (HCC) is one of the most common tumors affecting a large population worldwide, with the fifth and seventh greatest mortality rates among men and women, respectively, and the third prime cause of mortality among cancer victims. Dimethyl itaconate (DI) has been reported to be efficacious in colorectal cancer by decreasing IL-1ß release from intestinal epithelial cells. In this study, diethylnitrosamine (DEN)-induced HCC in male albino Wistar rats was treated with DI as an anticancer drug. The function and molecular mechanism of DI against HCC in vivo were assessed using histopathology, enzyme-linked immunosorbent assay (ELISA), and Western blot studies. Metabolomics using 1H-NMR was used to investigate metabolic profiles. As per molecular insights, DI has the ability to trigger mitochondrial apoptosis through iNOS- and eNOS-induced activation of the NF-κB/Bcl-2 family of proteins, CytC, caspase-3, and caspase-9 signaling cascade. Serum metabolomics investigations using 1H-NMR revealed that aberrant metabolites in DEN-induced HCC rats were restored to normal following DI therapy. Furthermore, our data revealed that the DI worked as an anti-HCC agent. The anticancer activity of DI was shown to be equivalent to that of the commercial chemotherapeutic drug 5-fluorouracil.

14.
J Control Release ; 125(1): 33-41, 2008 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-18006101

RESUMO

Floating in situ gelling system of clarithromycin (FIGC) was prepared using gellan as gelling polymer and calcium carbonate as floating agent for potentially treating gastric ulcers, associated with Helicobacter pylori. Gellan based FIGC was prepared by dissolving varying concentrations of gellan in deionized water to which varying concentrations of drug and sucralfate were dispersed well. The formulation parameters like concentrations of gellan gum and sucralfate influenced the rate and extent of in vitro drug release significantly from FIGC. The addition of sucralfate to the formulation significantly suppressed the degradation of clarithromycin at low pH. The in vivo H. pylori clearance efficacy of prepared FIGC and clarithromycin suspension following oral administration, to H. pylori infected Mongolian gerbils was examined by polymerase chain reaction (PCR) technique and by a microbial culture method. FIGC showed a significant anti-H. pylori effect than that of clarithromycin suspension. The in situ gel formulation with sucralfate cleared H. pylori more effectively than that of formulation without sucralfate. In addition, the required amount of clarithromycin for eradication of H. pylori was found to be less from FIGC than from the corresponding clarithromycin suspension. It was concluded that prolonged gastrointestinal residence time and enhanced clarithromycin stability resulting from the floating in situ gel of clarithromycin might contribute better for complete clearance of H. pylori.


Assuntos
Antibacterianos/administração & dosagem , Claritromicina/administração & dosagem , Sistemas de Liberação de Medicamentos/métodos , Mucosa Gástrica/metabolismo , Infecções por Helicobacter/tratamento farmacológico , Helicobacter pylori/efeitos dos fármacos , Animais , Antibacterianos/farmacocinética , Antibacterianos/uso terapêutico , Disponibilidade Biológica , Claritromicina/farmacocinética , Claritromicina/uso terapêutico , Portadores de Fármacos/química , Composição de Medicamentos , Estabilidade de Medicamentos , Géis/química , Gerbillinae , Infecções por Helicobacter/microbiologia , Concentração de Íons de Hidrogênio , Masculino , Polissacarídeos Bacterianos/química , Solubilidade , Estômago/microbiologia , Sucralfato/química , Viscosidade
15.
Curr Drug Deliv ; 4(3): 249-56, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17627499

RESUMO

Metformin microspheres with sodium alginate alone and in combination with gellan were prepared using an emulsion-cross linking method. The prepared microspheres were evaluated for their physico-chemical characteristics like particle size, morphology using SEM, incorporation efficiency, equilibrium water content (swelling) and in vitro drug release. The effect of various formulation variables like polymer concentration (sodium alginate; and proportion of gellan in microspheres prepared by a combination of sodium alginate and gellan), drug loading, crosslinking agent concentration and cross-linking time on the in vitro dissolution of the prepared microspheres were evaluated. The results showed that both the particle size and the incorporation efficiency were proportional to the polymer concentration. In case of microspheres containing both sodium alginate and gellan, the mean diameter and the incorporation efficiency were higher than the corresponding microspheres containing only alginate, both increasing with an increase in proportion of gellan. The prepared microspheres were found to be discrete and spherical in shape and were successful in sustaining the drug release for 8 hours. Incorporation of gellan caused a significant decrease in drug release. The release followed a biphasic profile, in all cases, characterized by an initial phase of moderate drug release followed by a phase of higher release. Further, the kinetic treatment of the dissolution data revealed the prevalence of matrix diffusion kinetics.


Assuntos
Alginatos/química , Portadores de Fármacos/química , Hipoglicemiantes/química , Metformina/química , Polissacarídeos Bacterianos/química , Cloreto de Cálcio/química , Reagentes de Ligações Cruzadas/química , Preparações de Ação Retardada , Difusão , Ácido Glucurônico/química , Ácidos Hexurônicos/química , Cinética , Microscopia Eletrônica de Varredura , Microesferas , Tamanho da Partícula , Solubilidade , Fatores de Tempo , Água
16.
Int J Pharm ; 335(1-2): 114-122, 2007 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-17141986

RESUMO

The aim of this study was to develop a new intra-gastric floating in situ gelling system for controlled delivery of amoxicillin for the treatment of peptic ulcer disease caused by Helicobacter pylori (H. pylori). Gellan based amoxicillin floating in situ gelling systems (AFIG) were prepared by dissolving varying concentrations of gellan gum in deionized water containing sodium citrate, to which varying concentrations of drug and calcium carbonate, as gas-forming agent, was added and dissolved by stirring. The formulation variables like concentration of gellan gum and calcium carbonate significantly affected the in vitro drug release from the prepared AFIG. The in vivo H. pylori clearance efficacy of prepared AFIG in reference to amoxicillin suspension following repeated oral administration to H. pylori infected Mongolian gerbils was examined by polymerase chain reaction (PCR) technique and by a microbial culture method. AFIG showed a significant anti-H. pylori effect in the in vivo gerbil model. It was noted that the required amount of amoxicillin for eradication of H. pylori was 10 times less in AFIG than from the corresponding amoxicillin suspension. The results further substantiated that the prepared AFIG has feasibility of forming rigid gels in the gastric environment and eradicated H. pylori from the gastrointestinal tract more effectively than amoxicillin suspension because of the prolonged gastrointestinal residence time of the formulation.


Assuntos
Amoxicilina/farmacologia , Antibacterianos/farmacologia , Portadores de Fármacos , Géis , Infecções por Helicobacter/tratamento farmacológico , Helicobacter pylori/efeitos dos fármacos , Polissacarídeos Bacterianos/química , Amoxicilina/química , Amoxicilina/uso terapêutico , Animais , Antibacterianos/química , Antibacterianos/uso terapêutico , Carbonato de Cálcio/química , Química Farmacêutica , Citratos/química , Preparações de Ação Retardada , Modelos Animais de Doenças , Composição de Medicamentos , Estudos de Viabilidade , Ácido Gástrico/química , Gerbillinae , Infecções por Helicobacter/microbiologia , Helicobacter pylori/isolamento & purificação , Concentração de Íons de Hidrogênio , Cinética , Masculino , Citrato de Sódio , Solubilidade , Estômago/efeitos dos fármacos , Estômago/microbiologia , Fatores de Tempo , Viscosidade
17.
Drug Deliv ; 10(1): 21-8, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12554360

RESUMO

Bioadhesive sodium alginate microspheres of Metoprolol tartrate (MT) for intranasal systemic delivery were prepared to avoid the first-pass effect, as an alternative therapy to injection, and to obtain improved therapeutic efficacy in the treatment of hypertension and angina pectoris. The microspheres (Ms) were prepared using emulsification--cross-linking method. The formulation variables were drug loading, polymer concentration, cross-linking agent concentration, and cross-linking time. The Ms were evaluated for characteristics, like particle size, incorporation efficiency, swelling ability, in vitro bioadhesion, in vitro drug release, and in vivo pharmacodynamic performance in rabbits against isoprenaline-induced tachycardia. Treatment of in vitro data to different kinetic equations indicated matrix-diffusion controlled drug delivery from sodium alginate Ms. Polymer concentration, cross-linking agent concentration, and cross-linking time influenced the drug release profiles significantly. In vivo studies indicated significantly improved therapeutic efficacy of MT from Ms with sustained and controlled inhibition of isoprenaline-induced tachycardia as compared with oral and nasal administration of drug solution.


Assuntos
Alginatos/administração & dosagem , Sistemas de Liberação de Medicamentos/métodos , Metoprolol/administração & dosagem , Administração Intranasal , Alginatos/farmacocinética , Animais , Avaliação Pré-Clínica de Medicamentos/métodos , Feminino , Ácido Glucurônico , Frequência Cardíaca/efeitos dos fármacos , Frequência Cardíaca/fisiologia , Ácidos Hexurônicos , Masculino , Metoprolol/farmacocinética , Microesferas , Coelhos , Tecnologia Farmacêutica/métodos
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