Development of Copper Nanoparticles Based Antimicrobial Coatings Mediated by Zingiber Officinale to Combat Antimicrobial Resistance

Novel antimicrobial agents with better functionality and multitarget modes of action are needed to combat the global rise in antibiotic resistance in bacteria. Copper nanoparticles (CuNPs) have been found to be efficient against many bacterial strains. Thus, combining CuNPs with antibiotics might provide a new approach for designing CuNPs-based antimicrobial drugs. This work is designed to produce CuNPs utilizing ginger rhizome extract as a capping and reducing agent and to evaluate their antibacterial, antioxidant, and antileishmanial properties. The biosynthesized CuNPs were physiochemically characterized by using UV-visible spectroscopy, Fourier transform infrared spectroscopy, X-ray powder diffraction, energy-dispersive X-ray spectroscopy, and scanning electron microscopy. Agar well diffusion assay, disc diffusion assay, free radical scavenging assay, and MTT assay were employed to determine the antibacterial, antioxidant, and antileishmanial potential of CuNPs. The successful contact between microbial cell membrane and CuNPs was thought to account for the microbial cell membrane leakage and thus CuNPs were found effective in inhibiting the growth of both gram positive and gram-negative bacteria including Proteus vulgaris, Pseudomonas aeruginosa, Escherichia coli, Staphylococcus epidermidis, and fungus Candida albicans. As determined by the size of inhibition zones, the maximum antibacteril activity was observed against Staphylococcus epidermidis (28.12±1.7 mm) and the minimum against Pseudomonas aeruginosa (11±0.5 mm). CuNPs have been demonstrated to have a synergistic impact in the suppression of bacteria when combined with broad and narrow spectrum antibiotics such as Ciprofloxacin, Gentamicin, Vancomycin, and Ceftriaxone etc. Furthermore, the significant antioxidant and antileishmanial properties make the CuNPs a multifunctional agent to be used in therapeutics. It is concluded that CuNPs have the potential to be used as antimicrobial agent in the development of alternatives to commercially available antibiotics and antibacterial coatings for medical implants to reduce the chances of infections

Bioactive Betulin and PEG Loaded Poly(vinyl alcohol) Nanofibers as Biodegradable Coatings for Neural Implants

Degradable polymeric coatings offer significant advantages when applied to medical implants. These coatings provide controlled degradation, ensuring that they gradually break down over time in harmony with the body’s healing processes. This controlled degradation can reduce the risk of long-term complications. The aim of our work was to prepare poly(vinyl alcohol) (PVA) nanofibers containing biodegradable polyanhydrides based on betulin disuccinate (DBB) and dicarboxylic derivatives of poly(ethylene glycol) (PEG) and to investigate their morphology, surface properties and biocompatibility. In this regard, PVA and DBB/PEG-loaded PVA nanofibers were fabricated using an electrospinning method. The average diameter of PVA and DBB/PEG-loaded PVA nanofibers were 132 nm and 247 nm, respectively. Surface roughness (Ra) of PVA and DBB/PEG-loaded PVA nanofibers was 96.2 nm and 117.6 nm, respectively, which is in agreement with previous studies on PVA nanofibers. To evaluate cell viability, human neuroblastoma SH-SY5Y cells were cultured for 48h on the surface of electrospun materials. All samples were found to be biocompatible, however, DBB/PEG-loaded PVA nanofibers indicated the highest percentage of viable cells when compared with PVA nanofibers and the control sample. The developed coating indicated promising properties for future application, particularly for the modification of metallic scaffolds used in neural tissue engineering

A flexible strain-responsive sensor fabricated from a biocompatible electronic ink via an additive-manufacturing process

Biosensor technologies are of great interest for applications in wearable electronics, soft robotics and implantable biomedical devices. To accelerate the adoption of electronics for chronic recording of physiological parameters in health and disease, there is a demand for biocompatible, conductive & flexible materials that can integrate with various tissues while remaining biologically inert. Conventional techniques used to fabricate biosensors, such as mask lithography and laser cutting, lack the versatility to produce easily customisable, micro-fabricated biosensors in an efficient, cost-effective manner. In this paper, we describe the development and characterisation of an electronic ink made from an environmentally sustainable copolymer - x-pentadecalactone-co-e-decalactone, (PDL) incorporating silver nanowires (AgNW), which are known for their antimicrobial and conductive properties. The composites were shown to possess a low percolation threshold (1% w/w of AgNW to PDL), achieve a low electrical resistance (320 +/- 9 O/sq) and a high electrical capacitance (2.06 +/- 0.06 mF/cm2). PDL nanocomposites were biocompatible, demonstrated in vitro through the promotion of neural adhesion and prevention of astrocyte activation. An optimised ink formulation was subsequently used to fabricate strain-responsive biosensors with high spatial resolution (sub-100 mm) using a direct write additive manufacturing process. Using a customized in vitro set-up, the sensitivity of these biosensors to biologically-relevant strains was assessed under simulated physiological conditions for 21 days. Critically, these 3D printed biosensors have applications in chronic prophylactic monitoring of pressure changes within the body and related pathologies.This publication has emanated from research conducted with the financial support of the Science Foundation Ireland (SFI) Technology Innovation Development Programme, grant no. 15/TIDA/2992 and was co-funded under the European Regional Development Fund under Grant Number 13/RC/2073 and the Hardiman PhD Research Scholarship from the National University of Ireland, Galway. This project has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No 713690. The authors acknowledge the facilities and scientific and technical assistance of the Centre for Microscopy & Imaging at the National University of Ireland Galway, a facility that is funded by NUIG and the Irish Government's Programme for Research in Third Level Institutions, Cycles 4 and 5, National Development Plan 20072013.r The Basque Government GV/EJ (Department of Education, Linguistic Politics and Culture) is also acknowledged for financial support to the consolidated research groups project IT927-16 (UPV/EHU, GIC/152)

Development of Multifunctional Biomaterials by Combining Electrochemistry, Microbiology, and Neural Tissue Engineering

The development of electroactive organic materials has been an unquestionable breakthrough for organic electronics, allowing for the design of polymer-based electrochromic and optoelectronic devices. Electroactive materials have been also considered as promising in the wide-field biomedical engineering, particularly considering their similarity with a living tissue in terms of elemental composition, surface morphology and mechanical properties. Electroactive materials are especially relevant in neural tissue engineering since the functionality of neural tissue is based on the transfer of electrical signals. Unfortunately, electroactive organic materials are also prone to bacterial colonization, which becomes as a considerable threat to patient’s health. In our group, we have been working on the development of biocompatible, antibacterial and conducting implant coatings based on conducting polymers [1] and diazonium-derived electroactive monolayers [2]. With the use of electrochemical techniques, we have fabricated a library of electroactive materials with various physicochemical characteristics, differing in the way how they interact with a living matter. Antimicrobial effects have been verified against model microorganisms: E. coli, S. aureus, and C. albicans, while the biocompatibility has been confirmed towards human neuroblastoma SH-SY5Y cells. Unique combination of biological activity of developed materials with their electroactivity allows for further enhancement of their modus operandi, through the possibility of applying electrical stimulation to facilitate treatment. In this way, the results of our work are a major step towards the development of advanced bio-optoelectronic-based therapies

Attenuated Glial Reactivity on Topographically Functionalized Poly(3,4-Ethylenedioxythiophene):P-Toluene Sulfonate (PEDOT:PTS) Neuroelectrodes Fabricated by Microimprint Lithography

Following implantation, neuroelectrode functionality is susceptible to deterioration via reactive host cell response and glial scar-induced encapsulation. Within the neuroengineering community, there is a consensus that the induction of selective adhesion and regulated cellular interaction at the tissue–electrode interface can significantly enhance device interfacing and functionality in vivo. In particular, topographical modification holds promise for the development of functionalized neural interfaces to mediate initial cell adhesion and the subsequent evolution of gliosis, minimizing the onset of a proinflammatory glial phenotype, to provide long-term stability. Herein, a low-temperature microimprint-lithography technique for the development of micro-topographically functionalized neuroelectrode interfaces in electrodeposited poly(3,4-ethylenedioxythiophene):p-toluene sulfonate (PEDOT:PTS) is described and assessed in vitro. Platinum (Pt) microelectrodes are subjected to electrodeposition of a PEDOT:PTS microcoating, which is subsequently topographically functionalized with an ordered array of micropits, inducing a significant reduction in electrode electrical impedance and an increase in charge storage capacity. Furthermore, topographically functionalized electrodes reduce the adhesion of reactive astrocytes in vitro, evident from morphological changes in cell area, focal adhesion formation, and the synthesis of proinflammatory cytokines and chemokine factors. This study contributes to the understanding of gliosis in complex primary mixed cell cultures, and describes the role of micro-topographically modified neural interfaces in the development of stable microelectrode interfaces

PRINCESA GUAYARMINA [Material gráfico]

FOTO DE DIBUJO DE GUAYARMINACopia digital. Madrid : Ministerio de Educación, Cultura y Deporte. Subdirección General de Coordinación Bibliotecaria, 201

Combining Cellulose and Cyclodextrins: Fascinating Designs for Materials and Pharmaceutics

Cellulose and cyclodextrins possess unique properties that can be tailored, combined, and used in a considerable number of applications, including textiles, coatings, sensors, and drug delivery systems. Successfully structuring and applying cellulose and cyclodextrins conjugates requires a deep understanding of the relation between structural, and soft matter behavior, materials, energy, and function. This review focuses on the key advances in developing materials based on these conjugates. Relevant aspects regarding structural variations, methods of synthesis, processing and functionalization, and corresponding supramolecular properties are presented. The use of cellulose/cyclodextrin conjugates as intelligent platforms for applications in materials science and pharmaceutical technology is also outlined, focusing on drug delivery, textiles, and sensors