Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 27
Filtrar
1.
Mol Pharm ; 21(7): 3566-3576, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38899552

RESUMO

Oxidative stress is pivotal in retinal disease progression, causing dysfunction in various retinal components. An effective antioxidant, such as probucol (PB), is vital to counteract oxidative stress and emerges as a potential candidate for treating retinal degeneration. However, the challenges associated with delivering lipophilic drugs such as PB to the posterior segment of the eye, specifically targeting photoreceptor cells, necessitate innovative solutions. This study uses formulation-based spray dry encapsulation technology to develop polymer-based PB-lithocholic acid (LCA) nanoparticles and assesses their efficacy in the 661W photoreceptor-like cell line. Incorporating LCA enhances nanoparticles' biological efficacy without compromising PB stability. In vitro studies demonstrate that PB-LCA nanoparticles prevent reactive oxygen species (ROS)-induced oxidative stress by improving cellular viability through the nuclear erythroid 2-related factor 2 (Nrf2)/heme oxygenase-1 (HO-1) pathway. These findings propose PB-LCA nanoparticles as a promising therapeutic strategy for oxidative stress-induced retinopathies.


Assuntos
Antioxidantes , Ácido Litocólico , Nanopartículas , Estresse Oxidativo , Polímeros , Probucol , Espécies Reativas de Oxigênio , Probucol/farmacologia , Probucol/administração & dosagem , Probucol/química , Estresse Oxidativo/efeitos dos fármacos , Nanopartículas/química , Espécies Reativas de Oxigênio/metabolismo , Ácido Litocólico/química , Ácido Litocólico/farmacologia , Animais , Polímeros/química , Linhagem Celular , Antioxidantes/farmacologia , Antioxidantes/química , Fator 2 Relacionado a NF-E2/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Camundongos , Heme Oxigenase-1/metabolismo , Humanos
2.
Int J Mol Sci ; 25(7)2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38612802

RESUMO

A novel organic-inorganic gliclazide-loaded composite bead was developed by an ionic gelation process using acidified CaCl2, chitosan and tetraethylorthosilicate (TEOS) as a crosslinker. The beads were manufactured by crosslinking an inorganic silicone elastomer (-OH terminated polydimethylsiloxane, PDMS) with TEOS at different ratios before grafting onto an organic backbone (Na-alginate) using a 32 factorial experimental design. Gliclazide's encapsulation efficiency (EE%) and drug release over 8 h (% DR 8 h) were set as dependent responses for the optimisation of a pharmaceutical formula (herein referred to as 'G op') by response surface methodology. EE % and %DR 8 h of G op were 93.48% ± 0.19 and 70.29% ± 0.18, respectively. G op exhibited a controlled release of gliclazide that follows the Korsmeyer-Peppas kinetic model (R2 = 0.95) with super case II transport and pH-dependent swelling behaviour. In vitro testing of G op showed 92.17% ± 1.18 cell viability upon testing on C2C12 myoblasts, indicating the compatibility of this novel biomaterial platform with skeletal muscle drug delivery.


Assuntos
Gliclazida , Gliclazida/farmacologia , Dimetilpolisiloxanos , Alginatos , Materiais Biocompatíveis
3.
Drug Dev Ind Pharm ; 46(8): 1238-1252, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32597264

RESUMO

INTRODUCTION: Therapeutic peptides are administered via parenteral route due to poor absorption in the gastrointestinal (GI) tract, instability in gastric acid, and GI enzymes. Polymeric drug delivery systems have achieved significant interest in pharmaceutical research due to its feasibility in protecting proteins, tissue targeting, and controlled drug release pattern. MATERIALS AND METHODS: In this study, the size, polydispersity index, and zeta potential of insulin-loaded nanoparticles were characterized by dynamic light scattering and laser Doppler micro-electrophoresis. The main and interaction effects of chitosan concentration and Dz13Scr concentration on the physicochemical properties of the prepared insulin-loaded nanoparticles (size, polydispersity index, and zeta potential) were evaluated statistically using analysis of variance. A robust procedure of reversed-phase high-performance liquid chromatography was developed to quantify insulin release in simulated GI buffer. Results and discussion: We reported on the effect of two independent parameters, including polymer concentration and oligonucleotide concentration, on the physical characteristics of particles. Chitosan concentration was significant in predicting the size of insulin-loaded CS-Dz13Scr particles. In terms of zeta potential, both chitosan concentration and squared term of chitosan were significant factors that affect the surface charge of particles, which was attributed to the availability of positively-charged amino groups during interaction with negatively-charged Dz13Scr. The excipients used in this study could fabricate nanoparticles with negligible toxicity in GI cells and skeletal muscle cells. The developed formulation could conserve the physicochemical properties after being stored for 1 month at 4 °C. CONCLUSION: The obtained results revealed satisfactory results for insulin-loaded CS-Dz13Scr nanoparticles (159.3 nm, pdi 0.331, -1.08 mV). No such similar study has been reported to date to identify the main and interactive significance of the above parameters for the characterization of insulin-loaded polymeric-oligonucleotide nanoparticles. This research is of importance for the understanding and development of protein-loaded nanoparticles for oral delivery.


Assuntos
Quitosana , Insulina/química , Nanopartículas , Oligonucleotídeos/química , Portadores de Fármacos , Insulina/administração & dosagem , Polímeros/química
4.
AAPS PharmSciTech ; 21(3): 108, 2020 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-32215761

RESUMO

The oral bioavailability of therapeutic proteins is limited by the gastrointestinal barriers. Encapsulation of labile proteins into nanoparticles is a promising strategy. In order to improve the stability of nanoparticles, lyophilisation has been used to remove water molecules from the suspension. Although various cryoprotections were employed in the preparation of lyophilised nanoparticles, the selection of cryoprotectant type and concentration in majority of the developed formulation was not justified. In this study, nanoparticles were fabricated by cationic chitosan and anionic Dz13Scr using complex coacervation. The effect of cryoprotectant types (mannitol, sorbitol, sucrose and trehalose) and their concentrations (1, 3, 5, 7, 10% w/v) on physiochemical properties of nanoparticles were measured. Cellular assays were performed to investigate the impact of selected cryoprotectant on cytotoxicity, glucose consumption, oral absorption mechanism and gastrointestinal permeability. The obtained results revealed that mannitol (7% w/v) could produce nanoparticles with small size (313.2 nm), slight positive charge and uniform size distribution. The addition of cryoprotectant could preserve the bioactivity of entrapped insulin and improve the stability of nanoparticles against mechanical stress during lyophilisation. The gastrointestinal absorption of nanoparticles is associated with both endocytic and paracellular pathways. With the use of 7% mannitol, lyophilised nanoparticles induced a significant glucose uptake in C2C12 cells. This work illustrated the importance of appropriate cryoprotectant in conservation of particle physiochemical properties, structural integrity and bioactivity. An incompatible cryoprotectant and inappropriate concentration could lead to cake collapse and formation of heterogeneous particle size populations.


Assuntos
Diabetes Mellitus/tratamento farmacológico , Insulina/química , Nanopartículas/química , Oligonucleotídeos/química , Animais , Crioprotetores/administração & dosagem , Estabilidade de Medicamentos , Liofilização/métodos , Insulina/administração & dosagem , Polímeros/química
5.
Anal Bioanal Chem ; 410(27): 6991-7006, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30206665

RESUMO

Therapeutic proteins are administered subcutaneously because of their instability in the gastrointestinal tract. Current research suggests that polymeric-based nanoparticles, microparticles and liposomes are ideal nanocarriers to encapsulate proteins for disease management. In order to develop a successful drug delivery system, it is crucial to determine drug release profile and stability. However, the non-active excipients in polymeric formulations can influence the quantification of proteins in analytical techniques. This study investigated the effect of nine common polymers on quantification of bovine serum albumin (BSA) using RP-HPLC method. The technique offers advantages such as short analytical time, high accuracy and selectivity. In the meantime, the technique can be employed to separate proteins including BSA, insulin and pigment epithelium-derived factor (PEDF). Furthermore, the RP-HPLC method was applied to quantify the drug release pattern of a novel BSA-loaded nanoparticulate formulation in simulated gastric and intestinal fluids. The nanoparticles were formulated by natural polymer (chitosan) and oligonucleotide (Dz13Scr) using complex coacervation. The prepared particles were found to have small size (337.87 nm), low polydispersity index (0.338) and be positively charged (10.23 mV). The in vitro drug release patterns were characterised using the validated RP-HPLC method over 12 h. Graphical abstract ᅟ.


Assuntos
Quitosana/química , Cromatografia Líquida , Nanopartículas/química , Oligonucleotídeos/química , Soroalbumina Bovina/química , Proteínas do Olho/química , Insulina/química , Fatores de Crescimento Neural/química , Polímeros/química , Reprodutibilidade dos Testes , Serpinas/química
6.
Pharm Dev Technol ; 23(2): 145-150, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28425308

RESUMO

INTRODUCTION: Ideal cell-containing microcapsules should be capable of maintaining cell viability and exhibit significant structural stability to support cellular functionality. To date, such microcapsules remain unavailable; thus, this study used our well-established microencapsulating methods to examine a total of 32 different microencapsulating formulations and correlate polymers' molecular weights (Mwt) and UDCA addition, with cell viability and microcapsules' stability, postmicroencapsulation. METHODS: MIN6 mouse-cloned pancreatic ß-cells were microencapsulated using control (n = 16; without UDCA) and test (n = 16; with UDCA) different polymers. Confocal microscopic imaging, cell viability, and microcapsules' stability were assessed. RESULTS: Best cell viability (>50%) was obtained at average Mwt of 50,000 g/mol (poly-l-ornithine), followed by 110,000 g/mol (poly-l-lysine). There was no linear correlation between Mwt and viability. Confocal imagining showed similar microcapsules' shape and cell distribution among all different polymers' molecular weights, which suggests that the microencapsulating method was efficient and maintained microcapsules' uniformity. UDCA addition resulted in enhanced osmotic stability of the microcapsules and improved cell viability, when the formulation contained 1% polylornithine, 1% polyethylene glycol, 20% Eudragit® NM30D, 1% polytetrafluoroethylene, or 5% pentamethylcyclopentasiloxane. CONCLUSIONS: UDCA addition improved microenvironmental conditions within the microcapsules but this effect was largely dependent on the polymer systems used.


Assuntos
Cápsulas/química , Cápsulas/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Diabetes Mellitus/tratamento farmacológico , Células Secretoras de Insulina/efeitos dos fármacos , Osmose/efeitos dos fármacos , Polímeros/química , Animais , Materiais Biocompatíveis/química , Linhagem Celular , Composição de Medicamentos/métodos , Camundongos , Peso Molecular , Polietilenoglicóis/química , Ácidos Polimetacrílicos/química , Politetrafluoretileno/química
7.
Pharm Res ; 33(5): 1182-90, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26818840

RESUMO

PURPOSE: The encapsulation of pancreatic ß-cells in biocompatible matrix has generated great interest in diabetes treatment. Our work has shown improved microcapsules when incorporating the bile acid ursodeoxycholic acid (UDCA), in terms of morphology and cell viability although cell survival remained low. Thus, the study aimed at incorporating the polyelectrolytes polyallylamine (PAA) and poly-l-ornithine (PLO), with the polymer sodium alginate (SA) and the hydrogel ultrasonic gel (USG) with UDCA and examined cell viability and functionality post microencapsulation. METHODS: Microcapsules without (control) and with UDCA (test) were produced using 1% PLO, 2.5% PAA, 1.8% SA and 4.5% USG. Pancreatic ß-cells were microencapsulated and the microcapsules' morphology, surface components, cellular and bile acid distribution, osmotic and mechanical stability as well as biocompatibilities, insulin production, bioenergetics and the inflammatory response were tested. RESULTS: Incorporation of UDCA at 4% into a PLO-PAA-SA formulation system increased cell survival (p < 0.01), insulin production (p < 0.01), reduced the inflammatory profile (TNF-α, IFN-ϒ, IL-6 and IL-1ß; p < 0.01) and improved the microcapsule physical and mechanical strength (p < 0.01). CONCLUSIONS: ß-cell microencapsulation using 1% PLO, 2.5% PAA, 1.8% SA, 4.5% USG and the bile acid UDCA (4%) has good potential in cell transplantation and diabetes treatment.


Assuntos
Alginatos/química , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Células Secretoras de Insulina/citologia , Ácido Ursodesoxicólico/química , Animais , Linhagem Celular , Sobrevivência Celular , Células Imobilizadas/citologia , Células Imobilizadas/metabolismo , Células Imobilizadas/transplante , Composição de Medicamentos , Ácido Glucurônico/química , Ácidos Hexurônicos/química , Insulina/metabolismo , Células Secretoras de Insulina/metabolismo , Células Secretoras de Insulina/transplante , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Camundongos , Pressão Osmótica , Fator de Necrose Tumoral alfa/metabolismo
8.
Adv Healthc Mater ; 13(16): e2303149, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38514042

RESUMO

Inner ear delivery requires safe and effective drug delivery vehicles incorporating high-viscosity formulations with permeation enhancers. This study designs novel thermoresponsive-smart polymer-bile acid and cyclodextrin-based nanogels for inner ear delivery. Nanogels are examined for their rheological and physical properties. The biocompatibility studies will be assessed on auditory and macrophage cell lines by investigating the impact of nanogels on cellular viability, mitochondrial respiration, glycolysis, intracellular oxidative stress, inflammatory profile, and macrophage polarization. Novel ther nanogels based on bile acid and beta-cyclodextrin show preserved porous nanogels' inner structure, exhibit non-Newtonian, shear-thinning fluid behavior, have fast gelation at 37 °C and minimal albumin adsorption on the surface. The nanogels have minimal impact on cellular viability, mitochondrial respiration, glycolysis, intracellular oxidative stress, and inflammatory profile of the auditory cell line House Ear Institute-Organ of Corti 1 after 24 h incubation. Nanogel exposure of 24 h to macrophage cell line RAW264.7 leads to decreased viability, mitochondrial dysfunction, and increased intracellular ROS and inflammatory cytokines. However, polarization changes from M2 anti-inflammatory to M1 pro-inflammatory macrophages are minimal, and inflammatory products of RAW264.7 macrophages do not overly disrupt the survivability of HEI-OC1 cells. Based on these results, thermoresponsive bile acid and cyclodextrin nanogels can be potential drug delivery vehicles for inner ear drug delivery.


Assuntos
Perda Auditiva , Nanogéis , Animais , Camundongos , Células RAW 264.7 , Perda Auditiva/tratamento farmacológico , Nanogéis/química , Ácidos e Sais Biliares/química , Sobrevivência Celular/efeitos dos fármacos , Ciclodextrinas/química , Polietilenoglicóis/química , Sistemas de Liberação de Medicamentos/métodos , Macrófagos/metabolismo , Macrófagos/efeitos dos fármacos , Linhagem Celular , Polietilenoimina
9.
Eur J Pharm Biopharm ; 190: 248-257, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37562725

RESUMO

Deoxycholic acid (DCA), lithocholic acid (LCA), and ursodeoxycholic acid (UDCA) are bile acids that may serve as permeation enhancers when incorporated within the nanogel matrix for drug delivery in the inner ear. In this study, thermoresponsive nanogels were formulated with DCA, LCA and UDCA and their rheological properties and biocompatibility were assessed. The impact of nanogel on cellular viability was evaluated via cell viability assay, the impact of nanogels on cellular bioenergetic parameters was estimated by Seahorse mito-stress test and glycolysis-stress test, while the presence of intracellular free radicals was assessed by reactive oxygen species assay. Nanogels showed a high level of biocompatibility after 24-hour exposure to auditory and macrophage cell lines, with minimal cytotoxicity compared to untreated control. Incubation with nanogels did not alter cellular respiration and glycolysis of the auditory cell line but showed possible mitochondrial dysfunction in macrophages, suggesting tissue-dependent effects of bile acids. Bile acid-nanogels had minimal impact on intracellular reactive oxygen species, with LCA demonstrating the most pro-oxidative behaviour. This study suggests that thermoresponsive nanogels with bile acid, particularly DCA and UDCA, may be promising candidates for inner ear drug delivery.


Assuntos
Ácidos e Sais Biliares , Ácido Desoxicólico , Nanogéis , Ácido Desoxicólico/farmacologia , Espécies Reativas de Oxigênio , Ácido Ursodesoxicólico/farmacologia , Ácido Litocólico , Linhagem Celular , Macrófagos
10.
Colloids Surf B Biointerfaces ; 222: 113014, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36427407

RESUMO

Deoxycholic acid (DCA) is a bile acid capable of forming micelles and modifying the properties of hydrogels. We incorporated DCA in sodium alginate (SA) and poloxamer 407 matrices creating novel DCA-copolymer hydrogel for therapeutic delivery. Hydrogels were assessed for common rheological properties. Biocompatibility and biological effect were examined on various cell lines. Cell viability was determent in normal and various hypoxic conditions, and full mitochondrial bioenergetic parameters were assessed in cell lines in order to illustrate hydrogel effects on survival, and cell metabolic profile within the hydrogels. Obtained data suggest that a low dose of DCA in permeable, biocompatible hydrogels can be beneficial for cells to combat hypoxic conditions.


Assuntos
Hidrogéis , Micelas , Hidrogéis/farmacologia , Linhagem Celular , Alginatos/farmacologia , Poloxâmero
11.
J Pharm Sci ; 112(3): 700-707, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36150468

RESUMO

The biocompatibility and effects on cells' bioactivity of developed pharmaceuticals are crucial properties, required to permit their safe delivery. Nanogel matrices offer a promising role in emerging pharmaceutics; however, it is crucial that they and their excipients do not demonstrate detrimental effects on the cells to which they interact. This study investigated the use of Teflon and the secondary bile acid deoxycholic acid in the formation of novel nanogel matrices. Each has properties which may be of benefit for the nanogels created and their use in the pharmaceutical industry. Rheological parameters and scanning electron microscopy studies were conducted. In order to assess the developed nanogels' impacts on cellular bioactivity, studies using Seahorse assays were conducted on three cell types, hepatic, muscle and pancreatic beta cells. Results demonstrated the addition of Teflon did not alter the morphological characteristics of resulting nanogels or the metabolic profiles of the cell lines. Interestingly, pancreatic beta cells highlighted the potential of Teflon to exert a protective profile from mitochondrial damage. Overall, the developed nanogels showed potentially promising profiles in certain studies conducted which may lead to future research.


Assuntos
Polietilenoglicóis , Politetrafluoretileno , Nanogéis , Polietilenoimina
12.
Ther Deliv ; 13(12): 591-604, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36861306

RESUMO

Chronic disorders such as diabetes mellitus are associated with multiple organ dysfunction, including retinopathy, neuropathy, nephropathy, peripheral vascular disease, and vascular disease. Lifelong subcutaneous insulin injections are currently the only treatment option for patients with Type 1 diabetes mellitus, and it poses numerous challenges. Since the breakthrough achieved from the Edmonton protocol in the year 2000, there has been important research to investigate whether islet cell transplantation can achieve long-term normoglycemia in patients without the need for insulin. The use of biopolymeric scaffold to enclose islet cells has also been explored to improve survivability and viability of islet cells. This review paper summarizes the latest research in using biopolymeric scaffolds in islet transplantation and how microfluidic devices can assist.


In this article we have highlighted several emerging biotechnologies and methodologies for the treatment of diabetes. We describe how cell transplant presents one viable method for diabetes treatment. Through this we outline several of the challenges associated with this technique as well as how new methods are being explored. Furthermore, we highlight how new devices are allowing for enhanced treatment screening for diabetes.


Assuntos
Ácidos e Sais Biliares , Diabetes Mellitus Tipo 1 , Humanos , Microfluídica , Insulina , Materiais Biocompatíveis
13.
Biomaterials ; 283: 121459, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35303546

RESUMO

The role of endogenous bile acids as lipid stabilizers aiding uptake of lipophilic nutrients via micelle formation and saponification effects is well documented and precedes their growing applications in pharmaceutical sciences. Their utility stems from their unique physico-chemical profile and ability to modulate immune cell signalling pathways. It has been shown that bile acids alter specific receptor-mediated pathways of cellular respiration and metabolism, providing potential clinical therapies for cardio-metabolic disorders such as diabetes mellitus, hypercholesterolemia, and heart disease. Additionally, some bile acids exert profound anti-oxidant, anti-inflammatory and immunosuppressant properties, and are effective at reducing blood pressure and alleviating hypertension. Their unique amphoteric properties and proven ability as permeability enhancers make them a desirable pharmaceutical excipient. When incorporated with various carbohydrates, polymers, hydrogels and/or polyelectrolytes to form micro- or nano-capsules, they provide enhanced thermodynamic, osmotic and structural stability, and cater for controlled delivery via specific tissue targeting, pH dependant release and temperature guided sol-gel complexation. Additionally, due to their immunosuppressant properties, they enhance the immunogenicity of encapsulated cells, increasing the feasibility of bioartificial organs as transplantable therapeutics. This review explores existing and future applications of bile acids and provides a synopsis of their role in advanced, novel therapeutic delivery systems.


Assuntos
Materiais Biocompatíveis , Hidrogéis , Ácidos e Sais Biliares , Bioengenharia , Nanotecnologia
14.
Biomolecules ; 12(1)2022 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-35053221

RESUMO

Recent studies in our laboratories have shown promising effects of bile acids in ➀ drug encapsulation for oral targeted delivery (via capsule stabilization) particularly when encapsulated with Eudragit NM30D® and ➁ viable-cell encapsulation and delivery (via supporting cell viability and biological activities, postencapsulation). Accordingly, this study aimed to investigate applications of bile acid-Eudragit NM30D® capsules in viable-cell encapsulation ready for delivery. Mouse-cloned pancreatic ß-cell line was cultured and cells encapsulated using bile acid-Eudragit NM30D® capsules, and capsules' images, viability, inflammation, and bioenergetics of encapsulated cells assessed. The capsules' thermal and chemical stability assays were also assessed to ascertain an association between capsules' stability and cellular biological activities. Bile acid-Eudragit NM30D® capsules showed improved cell viability (e.g., F1 < F2 & F8; p < 0.05), insulin, inflammatory profile, and bioenergetics as well as thermal and chemical stability, compared with control. These effects were formulation-dependent and suggest, overall, that changes in ratios of bile acids to Eudragit NM30D® can change the microenvironment of the capsules and subsequent cellular biological activities.


Assuntos
Anti-Inflamatórios , Ácidos e Sais Biliares , Células Imobilizadas/metabolismo , Colesterol , Células Secretoras de Insulina/metabolismo , Nanocápsulas , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Ácidos e Sais Biliares/química , Ácidos e Sais Biliares/farmacologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Colesterol/química , Colesterol/farmacologia , Camundongos , Nanocápsulas/química , Nanocápsulas/uso terapêutico , Ácidos Polimetacrílicos/química , Ácidos Polimetacrílicos/farmacologia
15.
Ther Deliv ; 13(1): 51-65, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34821516

RESUMO

Microencapsulation of formulation designs further expands the field and offers the potential for use in developing bioartificial organs via cell encapsulation. Combining formulation design and encapsulation requires ideal excipients to be determined. In terms of cell encapsulation, an environment which allows growth and functionality is paramount to ensuring cell survival and incorporation into a bioartificial organ. Hence, excipients are examined for both individual properties and benefits, and compatibility with encapsulated active materials. Polymers are commonly used in microencapsulation, offering protection from the immune system. Bile acids are emerging as a tool to enhance delivery, both biologically and pharmaceutically. Therefore, this review will focus on bile acids and polymers in formulation design via microencapsulation, in the field of bioartificial organ development.


Assuntos
Encapsulamento de Células , Excipientes , Ácidos e Sais Biliares , Composição de Medicamentos , Dispositivos Lab-On-A-Chip , Polímeros/química
16.
Carbohydr Polym ; 251: 117096, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33142634

RESUMO

This study aimed to explore the potential of bacterial cellulose nanocrystals (BCNs) loaded with nisin against selected meat spoilage lactic acid bacteria (LAB) in vitro. BCNs were produced by H2SO4 hydrolysis, and nisin-loaded BCNs were produced through the complexation method. All nanocrystals were assessed for their zeta-potential, encapsulation efficiency and antimicrobial activity. Different nisin concentrations were tested and the most effective nanocrystals were further characterised. BCNs had an average zeta-potential of - 43 mV and all nisin-loaded BCNs produced with 5 mg/ml BCNs suspension had zeta-potential values ≥- 30 mV. The encapsulation efficiency of nisin varied from 80.5 to 93.3 % and crystallinity of BCNs was not influenced by nisin encapsulation. Microbial inactivation was achieved by BCN loaded with 2.0 and 2.5 mg/ml nisin. Therefore, nisin-loaded BCNs may be used as antimicrobial agents in active food packaging.


Assuntos
Anti-Infecciosos/farmacologia , Celulose/química , Conservação de Alimentos/métodos , Lacticaseibacillus rhamnosus/efeitos dos fármacos , Carne/microbiologia , Nanopartículas/administração & dosagem , Nisina/farmacologia , Animais , Anti-Infecciosos/química , Bactérias/química , Embalagem de Alimentos/métodos , Carne/análise , Nanopartículas/química , Nisina/química
17.
J Mater Chem B ; 9(10): 2532-2546, 2021 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-33660730

RESUMO

Finding the right balance in mechanical properties and degradation rate of biodegradable materials for biomedical applications is challenging, not only at the time of implantation but also during biodegradation. For instance, high elongation at break and toughness with a mid-term degradation rate are required for tendon scaffold or suture application, which cannot be found in each alpha polyester individually. Here, we hypothesise that blending semi-crystalline poly(p-dioxanone) (PDO) and poly(lactide-co-caprolactone) (LCL) in a specific composition will enhance the toughness while also enabling tailored degradation times. Hence, blends of PDO and LCL (PDO/LCL) were prepared in varying concentrations and formed into films by solvent casting. We thoroughly characterised the chemical, thermal, morphological, and mechanical properties of the new blends before and during hydrolytic degradation. Cellular performance was determined by seeding mouse fibroblasts onto the samples and culturing for 72 hours, before using proliferation assays and confocal imaging. We found that an increase in LCL content causes a decrease in hydrolytic degradation rate, as indicated by induced crystallinity, surface and bulk erosions, and tensile properties. Interestingly, the noncytotoxic blend containing 30% PDO and 70% LCL (PDO3LCL7) resulted in small PDO droplets uniformly dispersed within the LCL matrix and demonstrated a tailored degradation rate and toughening behaviour with a notable strain-hardening effect reaching 320% elongation at break; over 3 times the elongation of neat LCL. In summary, this work highlights the potential of PDO3LCL7 as a biomaterial for biomedical applications like tendon tissue engineering or high-performance absorbable sutures.


Assuntos
Materiais Biocompatíveis/química , Dioxanos/química , Poliésteres/química , Polímeros/química , Engenharia Tecidual/métodos , Animais , Materiais Biocompatíveis/uso terapêutico , Linhagem Celular , Proliferação de Células , Fibroblastos/citologia , Fibroblastos/metabolismo , Congelamento , Hidrólise , Interações Hidrofóbicas e Hidrofílicas , Cinética , Ligamentos , Camundongos , Temperatura , Tendões , Resistência à Tração , Fatores de Tempo
18.
Ther Deliv ; 11(7): 415-429, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32594887

RESUMO

Aim: To develop a new self-emulsified silicon-grafted-alginate platform for pharmaceutical delivery. The produced biocompatible polymeric blend would be used to encapsulate metformin by a vibrational jet-flow ionotropic gelation process. Materials & methods: Polydimethylsiloxane was homogenized with alginate to prepare a stable polymeric mixture to which metformin was added. A metformin-loaded polymeric vehicle was then pumped through Buchi B-390 into CaCl2 to produce microcapsules. Results & conclusion: The platform showed a powerful, pseudoplastic thixotropic and demonstrated strong, efficient and wide applications of polydimethylsiloxane-customized technology in drug delivery and stability. A substantial improvement in drug loading, encapsulation efficiency and flow properties were noticed in siliconized microcapsules compared with the control.


Assuntos
Alginatos , Hipoglicemiantes , Cápsulas , Dimetilpolisiloxanos , Sistemas de Liberação de Medicamentos
19.
Expert Opin Drug Deliv ; 17(10): 1361-1376, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32597249

RESUMO

INTRODUCTION: Oral delivery is the most common administrated drug delivery path. However, oral administration of lipophilic drugs has some limitations: they have poor dose-response due to low and varied dissolution kinetics and oral bioavailability with sub-optimal dissolution within the aqueous gastrointestinal microenvironment. Therefore, there is a need for robust formulating methods that protect the drug until it reaches to its optimum absorption site, allowing its optimum pharmacological effects via increasing its intestinal permeation and bioavailability. AREA COVERED: Herein, we provide insights on orally administered lipophilic drug delivery systems. The detailed description of the obstacles associated with the oral bioavailability of lipophilic drugs are also discussed. Following this, techniques to overcome these obstacles with much emphasis on optimal safety and efficacy are addressed. Newly designed ionic vibrational jet flow encapsulation technology has enormous growth in lipophilic drug delivery systems, which is discussed thereafter. EXPERT OPINION: Researchers have shown interest in drug's encapsulation. A combination of drug-bile acid and microencapsulation methods can be one promising strategy to improve the oral delivery of lipophilic drugs. However, the most critical aspect of this approach is the selection of bile acids, polymer, and encapsulation technology.


Assuntos
Alginatos/química , Sistemas de Liberação de Medicamentos , Preparações Farmacêuticas/administração & dosagem , Administração Oral , Animais , Disponibilidade Biológica , Humanos , Polímeros/química , Tecnologia
20.
J Food Sci ; 85(7): 2153-2163, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32572986

RESUMO

The application of bacterial cellulose (BC) as a wrapping material for vacuum-packaged beef was studied and compared against unwrapped beef for up to 3 weeks. The impact of BC wrap on the weight loss, purge accumulation, and drip loss were assessed along with low-field nuclear magnetic resonance, physicochemical, microbiological, and sensorial evaluations. The BC wrap significantly (P < 0.05) reduced purge accumulation in vacuum packages which was confirmed by an increased swelling ratio and scanning electron microscopy images. Colorimetric measurements showed significantly (P < 0.05) increased redness and yellowness values in wrapped samples compared to unwrapped samples. BC wrap did not affect pH, tenderness, and odor of meat, but significantly (P < 0.05) increased lipid oxidation, and numbers of lactic acid bacteria and Brochothrix thermosphacta counts. This study shows that BC wrap has potential as a purge absorbent in vacuum packaged meat. PRACTICAL APPLICATION: Bacteria cellulose has good water holding capacity that can be utilized to absorb purge exudate from beef. It helps to improve the appearance and consequently consumer acceptance of vacuum packed beef.


Assuntos
Celulose/química , Embalagem de Alimentos/métodos , Conservação de Alimentos/métodos , Carne/análise , Adsorção , Animais , Bactérias/química , Bactérias/metabolismo , Bovinos , Cor , Microbiologia de Alimentos , Embalagem de Alimentos/instrumentação , Conservação de Alimentos/instrumentação , Humanos , Lactobacillales/crescimento & desenvolvimento , Carne/microbiologia , Paladar , Vácuo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA