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1.
Int J Pharm ; 653: 123879, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38320676

RESUMO

Phospholipid-based nanosystems show promising potentials for oral administration of hydrophobic drugs. The study introduced a novel approach to optimize posaconazole-loaded phospholipid-based nanoformulation using the design of experiments, machine learning, and Technique for Order of Preference by Similarity to the Ideal Solution. These approaches were used to investigate the impact of various variables on the encapsulation efficiency (EE), particle size, and polydispersity index (PDI). The optimized formulation, with %EE of âˆ¼ 74 %, demonstrated a particle size and PDI of 107.7 nm and 0.174, respectively. The oral pharmacokinetic profiles of the posaconazole suspension, empty nanoformulation + drug suspension, and drug-loaded nanoformulation were evaluated. The nanoformulation significantly increased maximum plasma concentration and the area under the drug plasma concentration-time curve (∼3.9- and 6.2-fold, respectively) and could be administered without regard to meals. MTT and histopathological examinations were carried out to evaluate the safety of the nanoformulation and results exhibited no significant toxicity. Lymphatic transport was found to be the main mechanism of oral delivery. Caco-2 cell studies demonstrated that the mechanism of delivery was not based on an increase in cellular uptake. Our study represents a promising strategy for the development of phospholipid-based nanoformulations as efficient and safe oral delivery systems.


Assuntos
Nanopartículas , Fosfolipídeos , Humanos , Fosfolipídeos/química , Células CACO-2 , Triazóis , Aprendizado de Máquina , Tamanho da Partícula , Administração Oral , Nanopartículas/química , Portadores de Fármacos/química , Disponibilidade Biológica
2.
Nat Protoc ; 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38413781

RESUMO

Engineered by nature, biological entities are exceptional building blocks for biomaterials. These entities can impart enhanced functionalities on the final material that are otherwise unattainable. However, preserving the bioactive functionalities of these building blocks during the material fabrication process remains a challenge. We describe a high-throughput protocol for the bottom-up self-assembly of highly concentrated phages into microgels while preserving and amplifying their inherent antimicrobial activity and biofunctionality. Each microgel is comprised of half a million cross-linked phages as the sole structural component, self-organized in aligned bundles. We discuss common pitfalls in the preparation procedure and describe optimization processes to ensure the preservation of the biofunctionality of the phage building blocks. This protocol enables the production of an antimicrobial spray containing the manufactured phage microgels, loaded with potent virulent phages that effectively reduced high loads of multidrug-resistant Escherichia coli O157:H7 on red meat and fresh produce. Compared with other microgel preparation methods, our protocol is particularly well suited to biological materials because it is free of organic solvents and heat. Bench-scale preparation of base materials, namely microporous films (the template for casting microgels) and pure concentrated phage suspension, requires 3.5 h and 5 d, respectively. A single production run, that yields over 1,750,000 microgels, ranges from 2 h to 2 d depending on the rate of cross-linking chemistry. We expect that this platform will address bottlenecks associated with shelf-stability, preservation and delivery of phage for antimicrobial applications, expanding the use of phage for prevention and control of bacterial infections and contaminants.

3.
ACS Appl Mater Interfaces ; 15(12): 16253-16265, 2023 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-36926806

RESUMO

Surface-mediated transmission of pathogens is a major concern with regard to the spread of infectious diseases. Current pathogen prevention methods on surfaces rely on the use of biocides, which aggravate the emergence of antimicrobial resistance and pose harmful health effects. In response, a bifunctional and substrate-independent spray coating is presented herein. The bifunctional coating relies on wrinkled polydimethylsiloxane microparticles, decorated with biocidal gold nanoparticles to induce a "repel and kill" effect against pathogens. Pathogen repellency is provided by the structural hierarchy of the microparticles and their surface chemistry, whereas the kill mechanism is achieved using functionalized gold nanoparticles embedded on the microparticles. Bacterial tests with methicillin-resistant Staphylococcus aureus and Pseudomonas aeruginosa reveal a 99.9% reduction in bacterial load on spray-coated surfaces, while antiviral tests with Phi6─a bacterial virus often used as a surrogate to SARS-CoV-2─demonstrate a 98% reduction in virus load on coated surfaces. The newly developed spray coating is versatile, easily applicable to various surfaces, and effective against various pathogens, making it suitable for reducing surface contamination in frequently touched, heavy traffic, and high-risk surfaces.


Assuntos
Desinfetantes , Nanopartículas Metálicas , Staphylococcus aureus Resistente à Meticilina , Ouro/farmacologia , Nanopartículas Metálicas/química , Desinfetantes/farmacologia , Bactérias , Antibacterianos/química
4.
Small ; 19(12): e2205761, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36587985

RESUMO

Engineered surfaces that repel pathogens are of great interest due to their role in mitigating the spread of infectious diseases. A robust, universal, and scalable omniphobic spray coating with excellent repellency against water, oil, and pathogens is presented. The coating is substrate-independent and relies on hierarchically structured polydimethylsiloxane (PDMS) microparticles, decorated with gold nanoparticles (AuNPs). Wettability studies reveal the relationship between surface texturing of micro- and/or nano-hierarchical structures and the omniphobicity of the coating. Studies of pathogen transfer with bacteria and viruses reveal that an uncoated contaminated glove transfers pathogens to >50 subsequent surfaces, while a coated glove picks up 104 (over 99.99%) less pathogens upon first contact and transfers zero pathogens after the second touch. The developed coating also provides excellent stability under harsh conditions. The remarkable anti-pathogen properties of this surface combined with its ease of implementation, substantiate its use for the prevention of surface-mediated transmission of pathogens.


Assuntos
Ouro , Nanopartículas Metálicas , Propriedades de Superfície , Interações Hidrofóbicas e Hidrofílicas , Tato
5.
ACS Appl Mater Interfaces ; 14(48): 53535-53545, 2022 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-36413608

RESUMO

Thrombus formation and infections caused by bacterial adhesion are the most common causes of failure in blood-contacting medical devices. Reducing the interaction of pathogens using repellent surfaces has proven to be a successful strategy in preventing device failure. However, designing scale-up methodologies to create large-scale repellent surfaces remains challenging. To address this need, we have created an all-polymeric lubricant-infused system using an industrially viable swelling-coagulation solvent (S-C) method. This induces hierarchically structured micro/nano features onto the surface, enabling improved lubricant infusion. Poly(3,3,3-trifluoropropylmethylsiloxane) (PTFS) was used as the lubricant of choice, a previously unexplored omniphobic nonvolatile silicone oil. This resulted in all-polymeric liquid-infused surfaces that are transparent and flexible with long-term stability. Repellent properties have been demonstrated using human whole blood and methicillin-resistant Staphylococcus aureus (MRSA) bacteria matrices, with lubricated surfaces showing 93% reduction in blood stains and 96.7% reduction in bacterial adherence. The developed material has the potential to prevent blood and pathogenic contamination for a range biomedical devices within healthcare settings.


Assuntos
Manchas de Sangue , Staphylococcus aureus Resistente à Meticilina , Humanos , Lubrificantes/farmacologia
6.
Front Microbiol ; 12: 785716, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35003018

RESUMO

Extracellular vesicles (EVs) originated from different cells of approximately all kinds of organisms, recently got more attention because of their potential in the treatment of diseases and reconstructive medicine. To date, lots of studies have been performed on mammalian-derived vesicles, but little attention has been paid to algae and marine cells as valuable sources of EVs. Proving the promising role of EVs in medicine requires sufficient resources to produce qualified microvesicles. Algae, same as its other sister groups, such as plants, have stem cells and stem cell niches. Previous studies showed the EVs in plants and marine cells. So, this study was set out to talk about algal extracellular vesicles. EVs play a major role in cell-to-cell communication to convey molecules, such as RNA/DNA, metabolites, proteins, and lipids within. The components of EVs depends on the origin of the primitive cells or tissues and the isolation method. Sufficient resources are needed to produce high-quality, stable, and compatible EVs as a drug or drug delivery system. Plant stem cells have great potential as a new controllable resource for the production of EVs. The EVs secreted from stem cells can easily be extracted from the cell culture medium and evaluated for medicinal uses. In this review, the aim is to introduce algae stem cells as well as EVs derived from algal cells. In the following, the production of the EVs¸ the properties of EVs extracted from these sources and their antimicrobial effects will be discussed.

7.
RSC Adv ; 11(14): 8346-8355, 2021 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-35423325

RESUMO

Bacterial biofilms are aggregates of bacterial cells embedded in a self-produced extracellular polymeric matrix. Biofilm formation has always been considered a major challenge for sensors used in underwater measurements, and is a primary source of measurement error, especially when it comes to long-term in situ monitoring. We demonstrate the utility of lytic bacteriophages (bacterial viruses) as a non-invasive strategy for removing bacterial biofilms formed on the gas permeable membrane of electrochemical dissolved oxygen sensors. Our results show that a 4 day Pseudomonas aeruginosa biofilm with a fully developed matrix significantly affected the sensor signal and response time, decreasing the signal by 32% and increasing the response time by 94%. In addition, measurements with the biofouled membrane had a very low signal to nose ratio compared to a clean sensor membrane. A single dose of overnight phage treatment effectively removed the biofilm (as indicated by scanning electron micrographs and fluorescence images of the membrane), without the need for repeated treatments. Furthermore, the sensor signal that had plummeted by 32% for a fully biofouled membrane, was returned to the original value (7.96 ± 0.27 mg L-1) after phage treatment and the signal to noise ratio (calculated as the ratio of mean to standard deviation) increased 8 folds for a phage-treated membrane compared to a biofouled membrane. Our data indicate near complete regeneration and signal recovery for the dissolved oxygen sensor, making the biofouled sensor reusable without the use of harsh chemicals that could destroy the fragile sensor membrane.

8.
Biomaterials ; 258: 120291, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32798745

RESUMO

Device-associated clot formation and poor tissue integration are ongoing problems with permanent and temporary implantable medical devices. These complications lead to increased rates of mortality and morbidity and impose a burden on healthcare systems. In this review, we outline the current approaches for developing single and multi-functional surface coating techniques that aim to circumvent the limitations associated with existing blood-contacting medical devices. We focus on surface coatings that possess dual hemocompatibility and biofunctionality features and discuss their advantages and shortcomings to providing a biocompatible and biodynamic interface between the medical implant and blood. Lastly, we outline the newly developed surface modification techniques that use lubricant-infused coatings and discuss their unique potential and limitations in mitigating medical device-associated complications.


Assuntos
Materiais Revestidos Biocompatíveis , Próteses e Implantes , Propriedades de Superfície
9.
Adv Colloid Interface Sci ; 277: 102121, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32092487

RESUMO

Liposomes, lipid-based vesicular systems, have attracted major interest as a means to improve drug delivery to various organs and tissues in the human body. Recent literature highlights the benefits of liposomes for use as drug delivery systems, including encapsulating of both hydrophobic and hydrophilic cargos, passive and active targeting, enhanced drug bioavailability and therapeutic effects, reduced systemic side effects, improved cargo penetration into the target tissue and triggered contents release. Pioneering work of liposomes researchers led to introduction of long-circulating, ligand-targeted and triggered release liposomes, as well as, liposomes containing nucleic acids and vesicles containing combination of cargos. Altogether, these findings have led to widespread application of liposomes in a plethora of areas from cancer to conditions such as cardiovascular, neurologic, respiratory, skin, autoimmune and eye disorders. There are numerous review articles on the application of liposomes in treatment of cancer, which seems the primary focus, whereas other diseases also benefit from liposome-mediated treatments. Therefore, this article provides an illustrated detailed overview of liposomal formulations, in vitro characterization and their applications in different disorders other than cancer. Challenges and future directions, which must be considered to obtain the most benefit from applications of liposomes in these disorders, are discussed.


Assuntos
Nanoestruturas/química , Animais , Doenças Autoimunes/tratamento farmacológico , Doenças Cardiovasculares/tratamento farmacológico , Sistemas de Liberação de Medicamentos , Oftalmopatias/tratamento farmacológico , Humanos , Lipossomos/química , Doenças do Sistema Nervoso/tratamento farmacológico , Doenças Respiratórias/tratamento farmacológico , Dermatopatias/tratamento farmacológico
10.
Artif Cells Nanomed Biotechnol ; 46(sup1): 1-14, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29186990

RESUMO

Sirolimus (rapamycin) is a mammalian target of rapamycin (mTOR) inhibitor with immunosuppressive, antiproliferative, antiangiogenic, antifungal, anti-restenosis and anti-inflammatory properties. However, its clinical application is often hampered by poor aqueous solubility, first-pass metabolism, transport by p-glycoprotein efflux pump, limited oral bioavailability and nonspecific distribution in off-target sites. Recently, various formulation strategies have emerged to overcome these limitations. Among these, pharmaceutical nanotechnology with numerous advantages has great potential for sirolimus delivery. Up to now, the only nanoparticle based FDA approved formulation in the market is Rapamune® tablet which is composed of drug nanocrystals. This review focuses on recent studies that have been investigated various nanostructured carriers such as liposomes, micelles, polymeric nanoparticles, nanocrystals, magnetic nanoparticles, albumin nanoparticles, solid dispersion nanoparticles and niosomes for sirolimus delivery (in organ transplantation, cancer, vascular restenosis, etc.).


Assuntos
Portadores de Fármacos/química , Nanomedicina/métodos , Sirolimo , Animais , Humanos , Lipossomos , Micelas , Nanopartículas/química , Sirolimo/química
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