Antibacterial Effect of Thymol Loaded SBA-15 Nanorods Incorporated in PCL Electrospun Fibers

For the effective management of infected chronic wounds, the incorporation of antimicrobial drugs into wound dressings can increase their local availability at the infection site. Mesoporous silicon dioxide SBA-15 is an excellent drug carrier with tunable drug release kinetics. In this work, synthesized SBA-15 loaded with the natural antimicrobial compound thymol (THY) was incorporated into polycaprolactone (PCL) electrospun nanofibers to obtain an advanced wound dressing. Rod-shaped particles with internal parallel channels oriented along the longitudinal axis (diameter: 138 ± 30 nm, length: 563 ± 100 nm) were loaded with 70.8 wt.% of THY. Fiber mats were prepared using these particles as nanofillers within polycaprolactone (PCL) electrospun fibers. The resulting mats contained 5.6 wt.% of THY and more than half of this loading was released in the first 7 h. This release would prevent an initial bacterial colonization and also inhibit or eliminate bacterial growth as in vitro shown against Staphylococcus aureus ATCC 25923. Minimal inhibitory concentration (MIC: 0.07 mg/mL) and minimal bactericidal concentration (MBC: 0.11 mg/mL) of released THY were lower than the amount of free THY required, demonstrating the benefit of drug encapsulation for a more efficient bactericidal capacity due to the direct contact between mats and bacteria.

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Porous Curdlan-Based Hydrogels Modified with Copper Ions as Potential Dressings for Prevention and Management of Bacterial Wound Infection—An In Vitro Assessment

Polymers ◽

10.3390/polym12091893 ◽

2020 ◽

Vol 12 (9) ◽

pp. 1893

Author(s):

Aleksandra Nurzynska ◽

Katarzyna Klimek ◽

Iga Swierzycka ◽

Krzysztof Palka ◽

Grazyna Ginalska

Keyword(s):

Bacterial Infections ◽

Chronic Wounds ◽

Copper Ions ◽

Bacterial Colonization ◽

Antibacterial Properties ◽

Biological Properties ◽

Wound Dressings ◽

Wound Fluid ◽

Potential Safety

Bacterial infections at the wound site still remain a huge problem for current medicine, as they may lead to development of chronic wounds. In order to prevent such infections, there is a need to use wound dressings that possess ability to inhibit bacterial colonization. In this study, three new curdlan-based biomaterials modified with copper ions were fabricated via simple and inexpensive procedure, and their structural, physicochemical, and biological properties in vitro were evaluated. Received biomaterials possessed porous structure, had ability to absorb high amount of simulated wound fluid, and importantly, they exhibited satisfactory antibacterial properties. Nevertheless, taking into account all evaluated properties of new curdlan-based biomaterials, it seems that Cur_Cu_8% is the most promising biomaterial for management of wounds accompanied with bacterial infections. This biomaterial exhibited the best ability to reduce Escherichia coli and Staphylococcus aureus growth and moreover, it absorbed the highest amount of simulated wound fluid as well as enabled optimal water vapor transmission. Furthermore, Cur_Cu_8% biomaterial possessed the best values of selective indexes, which determine its potential safety in vitro. Thus, Cur_Cu_8% hydrogel may be considered as a promising candidate for management of infected wounds as well as it may constitute a good platform for further modifications.

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Polymer/Iron-Based Layered Double Hydroxides as Multifunctional Wound Dressings

Pharmaceutics ◽

10.3390/pharmaceutics12111130 ◽

2020 ◽

Vol 12 (11) ◽

pp. 1130

Author(s):

Mariana Pires Figueiredo ◽

Ana Borrego-Sánchez ◽

Fátima García-Villén ◽

Dalila Miele ◽

Silvia Rossi ◽

...

Keyword(s):

Drug Release ◽

High Performance ◽

Mechanical Performance ◽

Release Kinetics ◽

Wound Dressings ◽

In Vitro Drug Release ◽

Improved Performance ◽

Double Hydroxide ◽

Double Hydroxides

This work presents the development of multifunctional therapeutic membranes based on a high-performance block copolymer scaffold formed by polyether (PE) and polyamide (PA) units (known as PEBA) and layered double hydroxide (LDH) biomaterials, with the aim to study their uses as wound dressings. Two LDH layer compositions were employed containing Mg2+ or Zn2+, Fe3+ and Al3+ cations, intercalated with chloride anions, abbreviated as Mg-Cl or Zn-Cl, or intercalated with naproxenate (NAP) anions, abbreviated as Mg-NAP or Zn-NAP. Membranes were structurally and physically characterized, and the in vitro drug release kinetics and cytotoxicity assessed. PEBA-loading NaNAP salt particles were also prepared for comparison. Intercalated NAP anions improved LDH–polymer interaction, resulting in membranes with greater mechanical performance compared to the polymer only or to the membranes containing the Cl-LDHs. Drug release (in saline solution) was sustained for at least 8 h for all samples and release kinetics could be modulated: a slower, an intermediate and a faster NAP release were observed from membranes containing Zn-NAP, NaNAP and Mg-NAP particles, respectively. In general, cell viability was higher in the presence of Mg-LDH and the membranes presented improved performance in comparison with the powdered samples. PEBA containing Mg-NAP sample stood out among all membranes in all the evaluated aspects, thus being considered a great candidate for application as multifunctional therapeutic dressings.

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Formulation and development of metformin-loaded microspheres using Khaya senegalensis (Meliaceae) gum as co-polymer

Future Journal of Pharmaceutical Sciences ◽

10.1186/s43094-020-00139-6 ◽

2020 ◽

Vol 6 (1) ◽

Author(s):

Chukwuebuka H. Ozoude ◽

Chukwuemeka P. Azubuike ◽

Modupe O. Ologunagba ◽

Sejoro S. Tonuewa ◽

Cecilia I. Igwilo

Keyword(s):

Controlled Release ◽

Sodium Alginate ◽

Release Kinetics ◽

Drug Carrier ◽

In Vitro Release ◽

Entrapment Efficiency ◽

Metformin Hydrochloride ◽

Scanning Calorimetry ◽

Khaya Senegalensis

Abstract Background Khaya gum is a bark exudate from Khaya senegalensis (Maliaecae) that has drug carrier potential. This study aimed to formulate and comparatively evaluate metformin-loaded microspheres using blends of khaya gum and sodium alginate. Khaya gum was extracted and subjected to preformulation studies using established protocols while three formulations (FA; FB and FC) of metformin (1% w/v)-loaded microspheres were prepared by the ionic gelation method using 5% zinc chloride solution as the cross-linker. The formulations contained 2% w/v blends of khaya gum and sodium alginate in the ratios of 2:3, 9:11, and 1:1, respectively. The microspheres were evaluated by scanning electron microscopy, Fourier transform-infrared spectroscopy, differential scanning calorimetry, entrapment efficiency, swelling index, and in vitro release studies. Results Yield of 28.48%, pH of 4.00 ± 0.05, moisture content (14.59% ± 0.50), and fair flow properties (Carr’s index 23.68 ± 1.91 and Hausner’s ratio 1.31 ± 0.03) of the khaya gum were obtained. FTIR analyses showed no significant interaction between pure metformin hydrochloride with excipients. Discrete spherical microspheres with sizes ranging from 1200 to 1420 μm were obtained. Drug entrapment efficiency of the microspheres ranged from 65.6 to 81.5%. The release of the drug from microspheres was sustained for the 9 h of the study as the cumulative release was 62% (FA), 73% (FB), and 80% (FC). The release kinetics followed Korsmeyer-Peppas model with super case-II transport mechanism. Conclusion Blends of Khaya senegalensis gum and sodium alginate are promising polymer combination for the preparation of controlled-release formulations. The blend of the khaya gum and sodium alginate produced microspheres with controlled release properties. However, the formulation containing 2:3 ratio of khaya gum and sodium alginate respectively produced microspheres with comparable controlled release profiles to the commercial brand metformin tablet.

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Surface Engineered Porous Silicon-based Nanostructures for Cancer Therapy

MRS Proceedings ◽

10.1557/opl.2012.483 ◽

2012 ◽

Vol 1416 ◽

Author(s):

Adi Tzur-Balter ◽

Naama Massad-Ivanir ◽

Ester Segal

Keyword(s):

Porous Silicon ◽

Surface Chemistry ◽

Electrochemical Etching ◽

Release Kinetics ◽

Drug Carrier ◽

Drug Loading ◽

Nitrogen Adsorption ◽

Cancer Drug ◽

Cytotoxicity Studies

ABSTRACTIn this work, nanostructured porous silicon (PSi) hosts, synthesized by electrochemical etching of Si, are designed to carry and release the anti cancer drug, mitoxantrone dihydrochloride (MTX). We study the effect of surface chemistry of the Si scaffold on its properties as a drug carrier. The freshly-etched PSi is modified by surface alkylation using thermal hydrosilylation with 1-dodecene. Fourier-transform infrared spectroscopy and nitrogen adsorption-desorption measurements are employed to characterize the PSi carriers after chemical modification. Both, drug loading efficiency and release kinetics are found to be significantly affected by surface chemistry of the PSi. In vitro cytotoxicity studies on human breast carcinoma (MDA-MB-231) cells show that the MTX released from the PSi hosts maintains its cytotoxic functionality.

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Programmable Release of Berberine Chloride Hydrate from Shape Memory Fibers Prepared from Core-Sheath Wet-Spinning Technology

Journal of Biomedical Nanotechnology ◽

10.1166/jbn.2019.2784 ◽

2019 ◽

Vol 15 (7) ◽

pp. 1432-1442 ◽

Cited By ~ 7

Author(s):

Jiamin Tang ◽

Ruifang Zhao ◽

Xueqian Yin ◽

Ya Wen ◽

Yidong Shi ◽

...

Keyword(s):

Shape Memory ◽

Release Kinetics ◽

Drug Carrier ◽

Wet Spinning ◽

Therapeutic Drug ◽

Composite Fibers ◽

Practical Applications ◽

Berberine Chloride ◽

Chloride Hydrate

Smart wet-spun fibers for highly programmable release of therapeutic drug have been rarely reported. Herein, thermalresponsive composite fibers were successfully prepared by core-sheath wet-spinning technology in present study. They consisted of a model drug of natural antibacterial berberine chloride hydrate (BCH) and a drug carrier of temperature responsive shape memory polyurethane (SMPU). The obtained composite fibers featured with well-controlled microscopic morphologies, exhibiting significantly enhanced thermal stability and superb mechanical properties. In vitro drug release test and corresponding release kinetics study were performed for investigation of BCH's release behavior. Results demonstrated that the release behaviors of BCH from the core-sheath fibers were pH-dependent, influenced by both diffusion from pore channels and the solubility of BCH in the release mediums, and BCH imbedded only in core part showed a longer release period compared with that in both core and sheath parts of the composite fibers. More importantly, the release rate of BCH can be simply controlled by changing the initial shapes of fibers through stretching and fixation of the stretched deformations. Furthermore, the antibacterial durability of the smart composites fibers was demonstrated and tracked according to the growth inhibition against both negative E. coli and positive S. aureus bacteria strains. All these results suggest that the developed composite fibers can be promising candidates as smart drug delivery vehicles for highly adjustable doses of target drugs towards practical applications.

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Preparation and Characterization of Chitosan–Alginate Polyelectrolyte Complexes Loaded with Antibacterial Thyme Oil Nanoemulsions

Applied Sciences ◽

10.3390/app9183933 ◽

2019 ◽

Vol 9 (18) ◽

pp. 3933 ◽

Cited By ~ 5

Author(s):

Hamid Hamedi ◽

Sara Moradi ◽

Alan E. Tonelli ◽

Samuel M. Hudson

Keyword(s):

Drug Release ◽

Uv Spectroscopy ◽

Drug Carrier ◽

Antibacterial Properties ◽

Wound Dressings ◽

Release Mechanism ◽

Vapor Permeability ◽

In Vitro Test ◽

Thyme Oil

Biomedical industries are attempting to utilize natural materials, as they are bio-compatible, non-toxic, and show bioactive properties, like antimicrobial activity. In this study, natural polyelectrolyte complexed chitosan/alginate films (PECs) were prepared via a casting/solvent evaporation technique, and their characteristics and drug release properties were investigated. PEC films made with two different overall polymer contents, 0.4 and 1 w/v%, were loaded with thyme oil nanoemulsion as drug carrier. The structure of the films was studied by FTIR and optical and scanning electron microscopy. Prepared PEC films had good mechanical and water vapor permeability properties. Release of the thyme oil from the pH-sensitive PEC films (TM-PEC) was detected and followed by UV spectroscopy. The results indicated that the drug release rate of TM-PEC films was the fastest when the chitosan content was 1 %w/v, and various mathematical models were analyzed for investigating the drug release mechanism. Antibacterial tests were performed by counting the number of surviving gram-negative and gram-positive bacteria. The in vitro test indicated the limitation Escherichia coli (E. coli) and Staphylococcus aureus (S.aureus) growth in the presence of TM-PEC films. The MTT test showed more cell viability of the TM-PEC film in comparison with that of the PEC film without TM. Based on the measured physical and antibacterial properties, the chitosan–alginate PEC films loaded with antibacterial essential oils can be considered for biomedical applications, such as wound dressings or controlled release systems.

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Preparation and in vitro release kinetics of nitrendipine-loaded PLLA–PEG–PLLA microparticles by supercritical solution impregnation process

RSC Advances ◽

10.1039/c9ra01068h ◽

2019 ◽

Vol 9 (28) ◽

pp. 16167-16175 ◽

Cited By ~ 8

Author(s):

Shiping Zhan ◽

Jingchang Wang ◽

Weijing Wang ◽

Liyun Cui ◽

Qicheng Zhao

Keyword(s):

Release Kinetics ◽

Drug Carrier ◽

In Vitro Release ◽

Impregnation Process ◽

Supercritical Solution ◽

Model Drug ◽

Polymer Microparticles ◽

Kinetics Of ◽

Vitro Release

In this work, drug-loaded polymer microparticles were prepared by a supercritical solution impregnation (SSI) process with nitrendipine as the model drug and PLLA–PEG–PLLA as the drug carrier.

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Crosslinked Electrospun UPM/PHBV/PVP Fibers for Sustained Drug Release

Materials Science Forum ◽

10.4028/www.scientific.net/msf.610-613.1331 ◽

2009 ◽

Vol 610-613 ◽

pp. 1331-1334 ◽

Cited By ~ 2

Author(s):

Jing Jing Zhang ◽

Jun Liu ◽

Hao Yu ◽

Yu Zhang ◽

Mei Fang Zhu ◽

...

Keyword(s):

Active Pharmaceutical Ingredient ◽

Treatment Method ◽

Electrospinning Process ◽

Wound Dressings ◽

In Vitro Dissolution ◽

Electrospun Fibers ◽

Sustained Drug Release ◽

Transdermal Drug Delivery Systems ◽

The Difference

Crosslinked UPM/PHBV/PVP fibers were successfully prepared using electrospinning process. The active pharmaceutical ingredient tetracycline hydrochloride (TH) was loaded onto the electrospun fibers through after-treatment method. Scanning electron microscopy (SEM), Fourier-transform infrared (FTIR) and in vitro dissolution tests were carried out to characterize the medicated electrospun fibers. The SEM and FTIR results clearly showed the difference between the UPM / PHBV and UPM/ PHBV/ PVPelectrospun fibers. The pharmaceutical tests results indicated that the fibers had good drug-loaded capability and sustained-release properties. The as-prepared fibers might find possible applications as wound dressings or transdermal drug delivery systems.

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Polyphenols: A Promising Avenue in Therapeutic Solutions for Wound Care

Applied Sciences ◽

10.3390/app11031230 ◽

2021 ◽

Vol 11 (3) ◽

pp. 1230

Author(s):

Inês Guimarães ◽

Sara Baptista-Silva ◽

Manuela Pintado ◽

Ana L. Oliveira

Keyword(s):

Antimicrobial Agents ◽

Chronic Wounds ◽

Wound Care ◽

Release Kinetics ◽

Wound Dressings ◽

Wound Site ◽

Biological Potential ◽

Efficient Alternative ◽

Biological Performance ◽

Complex Wounds

In chronic wounds, the regeneration process is compromised, which brings complexity to the therapeutic approaches that need to be adopted, while representing an enormous loss in the patients’ quality of life with consequent economical costs. Chronic wounds are highly prone to infection, which can ultimately lead to septicemia and morbidity. Classic therapies are increasing antibiotic resistance, which is becoming a critical problem beyond complex wounds. Therefore, it is essential to study new antimicrobial polymeric systems and compounds that can be effective alternatives to reduce infection, even at lower concentrations. The biological potential of polyphenols allows them to be an efficient alternative to commercial antibiotics, responding to the need to find new options for chronic wound care. Nonetheless, phenolic compounds may have some drawbacks when targeting wound applications, such as low stability and consequent decreased biological performance at the wound site. To overcome these limitations, polymeric-based systems have been developed as carriers of polyphenols for wound healing, improving its stability, controlling the release kinetics, and therefore increasing the performance and effectiveness. This review aims to highlight possible smart and bio-based wound dressings, providing an overview of the biological potential of polyphenolic agents as natural antimicrobial agents and strategies to stabilize and deliver them in the treatment of complex wounds. Polymer-based particulate systems are highlighted here due to their impact as carriers to increase polyphenols bioavailability at the wound site in different types of formulations.

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In Vitro Investigation of Thiol-Functionalized Cellulose Nanofibrils as a Chronic Wound Environment Modulator

Polymers ◽

10.3390/polym13020249 ◽

2021 ◽

Vol 13 (2) ◽

pp. 249

Author(s):

Anna Blasi-Romero ◽

Carlos Palo-Nieto ◽

Corine Sandström ◽

Jonas Lindh ◽

Maria Strømme ◽

...

Keyword(s):

Protease Activity ◽

Chronic Wounds ◽

Chronic Wound ◽

Cellulose Nanofibrils ◽

Dermal Fibroblasts ◽

Wound Dressings ◽

Thiol Groups ◽

The Stability ◽

Over Time

There is currently a huge need for new, improved therapeutic approaches for the treatment of chronic wounds. One promising strategy is to develop wound dressings capable of modulating the chronic wound environment (e.g., by controlling the high levels of reactive oxygen species (ROS) and proteases). Here, we selected the thiol-containing amino acid cysteine to endow wood-derived cellulose nanofibrils (CNF) with bioactivity toward the modulation of ROS levels and protease activity. Cysteine was covalently incorporated into CNF and the functionalized material, herein referred as cys-CNF, was characterized in terms of chemical structure, degree of substitution, radical scavenging capacity, and inhibition of protease activity. The stability of the thiol groups was evaluated over time, and an in vitro cytotoxicity study with human dermal fibroblasts was performed to evaluate the safety profile of cys-CNF. Results showed that cys-CNF was able to efficiently control the activity of the metalloprotease collagenase and to inhibit the free radical DPPH (1,1-Diphenyl-2-picrylhydrazyl radical), activities that were correlated with the presence of free thiol groups on the nanofibers. The stability study showed that the reactivity of the thiol groups challenged the bioactivity over time. Nevertheless, preparing the material as an aerogel and storing it in an inert atmosphere were shown to be valid approaches to increase the stability of the thiol groups in cys-CNF. No signs of toxicity were observed on the dermal fibroblasts when exposed to cys-CNF (concentration range 0.1–0.5 mg/mL). The present work highlights cys-CNF as a promising novel material for the development of bioactive wound dressings for the treatment of chronic wounds.

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