Diverse Applications In Biomedicine Research Articles

Impact of multi‐walled carbon nanotubes on the thermal, mechanical, and electrical properties of guar gum hydrogel

AbstractThis research investigates the transformative impact of incorporating unmodified multi‐walled carbon nanotubes (um‐MWCNTs) on properties of guar gum (GG)‐based hydrogel. The study focuses on the enhancement of thermal stability, mechanical strength, and electrical properties of hydrogel composite. Thermal analysis reveals a significant increase in residual weight remaining at 430°C from 3% to 10% with the addition of 0.2 wt% um‐MWCNTs to GG hydrogel. Viscoelastic properties of hydrogel composite investigated by rheology analysis observed that enhancements in storage modulus from 0.2 to 2.2 MPa indicative of enhanced structural integrity. Moreover, electrical conductivity exhibits a substantial increase with the addition of nanotubes, indicating the potential applicability of the composite in electronic and sensing applications. This research showcases the potential of GG/um‐MWCNT composites for diverse applications in biomedicine, sensors, and advanced materials.Highlights Distribution of um‐MWCNTs into guar‐gum matrix to obtain maximum benefits. Inclusion of um‐MWCNTs improves the rheological properties of GG/um‐MWCNTs composites. Rheological properties can be tuned with um‐MWCNT content. MWCNTs improved thermal stability of the GG hydrogel. MWCNTs improved electrical conductivity of the GG hydrogel.

Exploring Swelling Behaviour of Chitosan-Based Hydrogels in Diverse Environmental Conditions

Hydrogels, versatile materials with diverse applications in biomedicine and beyond, have garnered significant attention due to their unique properties. Among these, chitosan-based hydrogels have emerged as promising candidates owing to their biocompatibility, biodegradability, and antimicrobial properties. The hydrogels were synthesized through cross-linking of chitosan graft copolymers with N-vinylpyrrolidone and other vinyl monomers, as well as through thermal methods in situ. The impact of cross-linking agent concentration on gel fraction yield and cross-linking efficiency was examined. The results indicate that higher cross-linking densities lead to reduced swelling capacity as a result of a denser network structure. The swelling behaviour of chitosan-based hydrogels under various environmental conditions, including pH, temperature and ionic strength were also investigated. It is found that swelling behaviour varied among different hydrogel formulations, with natural and vinyl graft copolymers exhibiting increased swelling in acidic environments. Semi-synthetic copolymers containing hydrophobic groups showed relatively lower swelling across pH ranges. Additionally, swelling kinetics were studied, revealing equilibrium reached at different time intervals depending on temperature and hydrogel composition. Furthermore, the effect of glucose concentration on swelling behaviour was explored, demonstrating decreased swelling with increasing glucose concentration. Overall, this comprehensive investigation provides valuable insights into the swelling behaviour of chitosan-based hydrogels, essential for optimizing their performance in biomedical applications.

Anabaena sp. A-1 mediated molybdenum oxide nanoparticles: A novel frontier in green synthesis, characterization and pharmaceutical properties.

Green-synthesized metal oxide nanoparticles have garnered considerable attention due to their simple, sustainable, and eco-friendly attributes, coupled with their diverse applications in biomedicine and environmental context. The current study shows a sustainable approach for synthesizing molybdenum oxide nanoparticles (MoONPs) utilizing an extract from Anabaena sp. A-1. This novel approach marks a significant milestone as various spectral approaches were employed for characterization of the green-synthesized MoONPs. Ultraviolet-visible (UV-Vis) spectroscopic analysis revealed a surface plasmon resonance (SPR) peak of MoONPs at 538 nm. Fourier transform infrared (FTIR) spectral analysis facilitated the identification of functional groups responsible for both the stability and production of MoONPs. Scanning electron microscopy (SEM) was utilized revealing a rod shape morphology of the MoONPs. X-ray diffraction (XRD) analysis yielded a calculated crystal size of 31 nm, indicating the crystalline nature of MoONPs. Subsequently, biological assays were employed to ascertain the potential of the bioengineered MoONPs. The 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay was used to quantify free radical scavenging activity, revealing an antioxidant capacity of 68.1% at 200 μg/mL. To evaluate antibacterial and antifungal efficacy, the disc diffusion method was employed across varying concentrations of MoONPs (6.25, 12.5, 25, 50, 100, 150, 200 μg/mL). Quantification of cytotoxicity was performed via a brine shrimp assay, yielding an IC50 value of 552.3 μg/mL, a metric of moderate cytotoxicity. To assess the biocompatibility of MoONPs, an antihemolytic assay was conducted, confirming their safety profile. Additionally, MoONPs exhibited non-toxic attributes in an insecticidal assay. Notably, in anti-inflammatory assay MoONPs showed an inactive nature towards the reactive oxygen species. In conclusion, these findings highlight the potential versatility of MoONPs in various biological applications, extending beyond their recognized anti-inflammatory and insecticidal properties. RESEARCH HIGHLIGHTS: This study marks an advancement in nanotechnology, exploring ways for MoONPs fabrication, representing a unique and unexplored research domain. Green-synthesized MoONPs using Anabaena sp. A-1 extract offers a sustainable and eco-friendly approach. Characterized by UV-Vis, FTIR, SEM, and XRD, MoONPs demonstrate rod-shaped morphology and crystalline nature. Bioengineered MoONPs exhibit versatility in biological applications, demonstrating notable antioxidant, antibacterial and antifungal efficacy, moderate cytotoxicity, biocompatibility, and insecticidal properties, emphasizing their multifaceted utility. The research findings highlight the potential utilization of MoONPs across a spectrum of biological applications, thereby suggesting their promising role in the realm of biomedicine and environmental context.

Evolutionary Reinforcement of Polymer Networks: A Stepwise-Enhanced Strategy for Ultrarobust Eutectogels.

Gel materials are appealing due to their diverse applications in biomedicine, soft electronics, sensors, and actuators. Nevertheless, the existing synthetic gels are often plagued by feeble network structures and inherent defects associated with solvents, which compromise their mechanical load-bearing capacity and cast persistent doubts about their reliability. Herein, combined with attractive deep eutectic solvent (DES), a stepwise-enhanced strategy is presented to fabricate ultrarobust eutectogels. It focuses on the continuous modulation and optimization of polymer networks through complementary annealing and solvent exchange processes, which drives a progressive increase in both quantity and mass of the interconnected polymer chains at microscopic scale, hence contributing to the evolutionary enhancement of network structure. The resultant eutectogel exhibits superb mechanical properties, including record-breaking strength (31.8MPa), toughness (76.0MJ m-3 ), and Young's modulus (25.6MPa), together with exceptional resistance ability to tear and crack propagation. Moreover, this eutectogel is able to be further programmed through photolithography to in situ create patterned eutectogel for imparting specific functionalities. Enhanced by its broad applicability to various DES combinations, this stepwise-enhanced strategy is poised to serve as a crucial template and methodology for the future development of robust gels.

Kinetically Limited Bulk Polymerization of Polymer Thin Films by Initiated Chemical Vapor Deposition.

An experimental study and kinetic model analysis of the initiated chemical vapor deposition (iCVD) of polymer thin films have been performed at saturated monomer vapor conditions. Previous iCVD kinetic studies have focused on subsaturated monomer conditions where polymer deposition kinetics is known to be limited by monomer adsorption. However, iCVD kinetics at saturated conditions have so far not been systematically investigated, and it remains unclear whether the adsorption-limited phenomenon would still apply at saturation, given the abundance of monomer for reaction. To probe this question, a series of depositions of poly(vinylpyrrolidone) (PVP) thin films as a model system were performed by iCVD at substrate temperatures from 10 to 25 °C at both fully saturated (100%) and subsaturated (50%) conditions. While the deposition rates at subsaturated conditions exhibit the expected adsorption-limited behavior, the deposition rates at saturated conditions unexpectedly show two distinct deposition regimes with reaction time: an initial adsorption-limited regime followed by a kinetically limited steady-state regime. In the steady-state regime, the deposition kinetics is found to be thermally activated by raising substrate temperature with an overall activation energy of +86 kJ/mol, which agrees reasonably well with the experimentally determined value of +89 kJ/mol in the literature for bulk PVP polymerization and a mechanistically derived value of +91 kJ/mol based on the bulk free radical polymerization mechanism of PVP. These findings open new operating windows for iCVD polymerization and thin-film growth in which fast polymer deposition can be achieved without substrate cooling that can greatly simplify the iCVD scale-up to roll-to-roll processing and enable iCVD polymerization of highly volatile monomers relevant for diverse applications in biomedicine, smart wearables, and renewable energy.

Single-atom nanozymes as promising catalysts for biosensing and biomedical applications

Single-atom nanozymes represent a unique class of enzyme mimics that exhibit maximal atomic utilization, a well-defined electronic/geometric structure, and high catalytic activity, and have found diverse applications in biomedicine and biosensing.

Electrochemical activation for sensing of three‐dimensional‐printed poly(lactic acid) using low‐pressure plasma

AbstractIntegrated electrochemical sensors in which plasma‐treated poly(lactic acid) (PLA) single material acts as both selective coating layer and electrochemical transductor (electrode) are prepared. Thus, three‐dimensional‐printed PLA specimens are transformed into electroresponsive material by applying a low‐pressure gas plasma treatment with three different gases: N2, O2, and air (79% N2 + 21% O2). Although all treated samples are able to electrochemically detect dopamine, the one derived from the treatment of low‐pressure O2 plasma exhibits the best performance as a sensor. Finally, cell adhesion assays demonstrate that the cell viability is higher for plasma‐treated PLA modified than for pristine PLA, making the former a promising, versatile, and powerful electroresponsive platform for diverse applications in biomedicine.

Improvement of aqueous stability and anti-osteoporosis properties of Zn-MOF coatings on titanium implants by hydrophobic raloxifene

Endowed with superior tailorability and functionality, metal–organic frameworks (MOFs) have been exploited for their diverse applications in biomedicine. However, the instability of MOFs under an aqueous environment causes an accelerated degradation preventing their clinical applications and commercialization. To address this issue, studies have reported the incorporation of hydrophobic functional groups into MOF to enhance its stability. In this study, we aimed to fabricate a multifunctional coating on titanium implants by exploiting the synergy between Zn-based MOFs and raloxifene (Ral). We theorized that the integration of MOF and Ral will not only locally deliver the drug, but also take advantage of the hydrophobic functional group of Ral to enhance the stability of MOF in an aqueous environment. The release studies showed a sustained release of both Zn2+ and Ral for more than 14 d. In-depth in vitro investigations also verified that MOF/Ral coatings significantly enhanced the cell viability and osteogenic differentiation of osteoblasts, as well as decreasing the tartrate-resistant acid phosphatase activity and osteoclastic biomarker expressions. In addition, both micro-computed tomography and immunohistochemical analysis further confirmed the efficacy of MOF/Ral coatings in the formation of new bone within the femurs of osteoporotic rats. The feasibility of MOF/Ral coated titanium implants in inhibiting osteolysis and promoting osteogenesis has undoubtedly proved their clinical prospects in the treatment of osteoporotic bone injury.

Geometric Lessons and Design Strategies for Nanoscale Protein Cages

Protein molecules bring a rich functionality to the field of designed nanoscale architectures. High-symmetry protein cages are rapidly finding diverse applications in biomedicine, nanotechnology, and imaging, but methods for their reliable and predictable construction remain challenging. In this study we introduce an approach for designing protein assemblies that combines ideas and favorable elements adapted from recent work. Cubically symmetric cages can be created by combining two simpler symmetries, following recently established principles. Here, two different oligomeric protein components are brought together in a geometrically specific arrangement by their separate genetic fusion to individual components of a heterodimeric coiled-coil polypeptide motif of known structure. Fusions between components are made by continuous α-helices to limit flexibility. After a computational design, we tested 10 different protein cage constructions experimentally, two of which formed larger assemblies. One produced the intended octahedral cage, ∼26 nm in diameter, while the other appeared to produce the intended tetrahedral cage as a minor component, crystallizing instead in an alternate form representing a collapsed structure of lower stoichiometry and symmetry. Geometric distinctions between the two characterized designs help explain the different degrees of success, leading to clearer principles and improved prospects for the routine creation of nanoscale protein architectures using diverse methods.

Erythrocyte-mediated delivery of bioorthogonal nanozymes for selective targeting of bacterial infections.

Bioorthogonal transformation of imaging and therapeutic substrates using transition metal catalysts (TMCs) provides a toolkit with diverse applications in biomedicine. Controlled localization of bioorthogonal catalysis is key for enhancing their therapeutic efficacy by minimizing off-target effects. Red blood cells (RBCs) are highly biocompatible and are susceptible to hemolysis by bacterial toxins, providing them with intrinsic targeting to bacterial infections. A hitchhiking strategy using RBCs is reported, that activates bioorthogonal catalysis at infection sites. A library of nanoparticles embedded with TMCs (nanozymes) featuring diverse functional groups with different binding ability to RBCs is generated. These engineered nanozymes bind to RBCs and subsequently release upon hemolysis by bacterial toxins, resulting in selective accumulation at the site of bacterial infections. The antimicrobial action is specific: catalytic activation of pro-antibiotics eradicated pathogenic biofilms without harming non-virulent bacterial species.

Libraries of Uniform Magnetic Multicore Nanoparticles with Tunable Dimensions for Biomedical and Photonic Applications.

Multicore iron oxide nanoparticles, also known as colloidal nanocrystal clusters, are magnetic materials with diverse applications in biomedicine and photonics. Here, we examine how both of their characteristic dimensional features, the primary particle and sub-micron colloid diameters, influence their magnetic properties and performance in two different applications. The characterization of these basic size-dependent properties is enabled by a synthetic strategy that provides independent control over both the primary nanocrystal and cluster dimensions. Over a wide range of conditions, electron microscopy and X-ray diffraction reveal that the oriented attachment of smaller nanocrystals results in their crystallographic alignment throughout the entire superstructure. We apply a sulfonated polymer with high charge density to prevent cluster aggregation and conjugate molecular dyes to particle surfaces so as to visualize their collection using handheld magnets. These libraries of colloidal clusters, indexed both by primary nanocrystal dimension (dp) and overall cluster diameter (Dc), form magnetic photonic crystals with relatively weak size-dependent properties. In contrast, their performance as MRI T2 contrast agents is highly sensitive to cluster diameter, not primary particle size, and is optimized for materials of 50 nm diameter (r2 = 364 mM-1 s-1). These results exemplify the relevance of dimensional control in developing applications for these versatile materials.

Hydration and Sorption Properties of Raw and Milled Flax Fibers.

The physicochemical and hydration properties of mechanically modified flax fibers (FFs) were investigated herein. Raw flax fibers (FF-R) were ball-milled and sieved through mesh with various aperture sizes (420, 210, and 125 μm) to achieve modified samples, denoted as FF-420, FF-210, and FF-125, respectively. The physicochemical and hydration properties of FF-R with variable particle sizes were characterized using several complementary techniques: microscopy (SEM), spectroscopy (FT-IR, XRD, and XPS), thermoanalytical methods (DSC and TGA), adsorption isotherms using gas/dye probes, and solvent swelling studies in liquid H2O. The hydration of FF biomass is governed by the micropore structure and availability of active surface sites, as revealed by the adsorption isotherm results and the TGA/DSC profiles of the hydrated samples. Gravimetric water swelling, water retention values, and vapor adsorption results provide further support that particle size reduction of FF-R upon milling parallels the changes in surface chemical and physicochemical properties relevant to adsorption/hydration in the modified FF materials. This study outlines a facile strategy for the valorization and tuning of the physicochemical properties of agricultural FF biomass via mechanical treatment for diverse applications in biomedicine, energy recovery, food, and biosorbents for environmental remediation.

Controlling the Size and Polymorphism of Calcium Carbonate Hybrid Particles Using Natural Biopolymers

Calcium carbonate (CaCO3) nanoparticles have diverse applications in biomedicine, including ultrasound imaging, biosensing, drug delivery, and theranostics. One of its crystal polymorphs, vaterite,...

Using Self-Assembling Peptides to Integrate Biomolecules into Functional Supramolecular Biomaterials.

Throughout nature, self-assembly gives rise to functional supramolecular biomaterials that can perform complex tasks with extraordinary efficiency and specificity. Inspired by these examples, self-assembly is increasingly used to fabricate synthetic supramolecular biomaterials for diverse applications in biomedicine and biotechnology. Peptides are particularly attractive as building blocks for these materials because they are based on naturally derived amino acids that are biocompatible and biodegradable; they can be synthesized using scalable and cost-effective methods, and their sequence can be tailored to encode formation of diverse architectures. To endow synthetic supramolecular biomaterials with functional capabilities, it is now commonplace to conjugate self-assembling building blocks to molecules having a desired functional property, such as selective recognition of a cell surface receptor or soluble protein, antigenicity, or enzymatic activity. This review surveys recent advances in using self-assembling peptides as handles to incorporate biologically active molecules into supramolecular biomaterials. Particular emphasis is placed on examples of functional nanofibers, nanovesicles, and other nano-scale structures that are fabricated by linking self-assembling peptides to proteins and carbohydrates. Collectively, this review highlights the enormous potential of these approaches to create supramolecular biomaterials with sophisticated functional capabilities that can be finely tuned to meet the needs of downstream applications.

An efficient way to model complex magnetite: Assessment of SCC-DFTB against DFT.

Magnetite has attracted increasing attention in recent years due to its promising and diverse applications in biomedicine. Theoretical modelling can play an important role in understanding magnetite-based nanomaterials at the atomic scale for a deeper insight into the experimental observations. However, calculations based on density functional theory (DFT) are too costly for realistically large models of magnetite nanoparticles. Classical force field methods are very fast but lack of precision and of the description of electronic effects. Therefore, a cheap and efficient quantum mechanical simulation method with comparable accuracy to DFT is highly desired. Here, a less computationally demanding DFT-based method, i.e., self-consistent charge density functional tight-binding (SCC-DFTB), is adopted to investigate magnetite bulk and low-index (001) surfaces with newly proposed parameters for Fe-O interactions. We report that SCC-DFTB with on-site Coulomb correction provides results in quantitatively comparable agreement with those obtained by DFT + U and hybrid functional methods. Therefore, SCC-DFTB is valued as an efficient and reliable method for the description magnetite. This assessment will promote SCC-DFTB computational studies on magnetite-based nanostructures that attract increasing attention for medical applications.

2-S-Lipoylcaffeic Acid, a Natural Product-Based Entry to Tyrosinase Inhibition via Catechol Manipulation.

Conjugation of naturally occurring catecholic compounds with thiols is a versatile and facile entry to a broad range of bioinspired multifunctional compounds for diverse applications in biomedicine and materials science. We report herein the inhibition properties of the caffeic acid- dihydrolipoic acid S-conjugate, 2-S-lipoylcaffeic acid (LC), on mushroom tyrosinase. Half maximum inhibitory concentration (IC50) values of 3.22 ± 0.02 and 2.0 ± 0.1 µM were determined for the catecholase and cresolase activity of the enzyme, respectively, indicating a greater efficiency of LC compared to the parent caffeic acid and the standard inhibitor kojic acid. Analysis of the Lineweaver–Burk plot suggested a mixed-type inhibition mechanism. LC proved to be non-toxic on human keratinocytes (HaCaT) at concentrations up to 30 µM. These results would point to LC as a novel prototype of melanogenesis regulators for the treatment of pigmentary disorders.

Nanobody-derived nanobiotechnology tool kits for diverse biomedical and biotechnology applications.

Owing to peculiar properties of nanobody, including nanoscale size, robust structure, stable and soluble behaviors in aqueous solution, reversible refolding, high affinity and specificity for only one cognate target, superior cryptic cleft accessibility, and deep tissue penetration, as well as a sustainable source, it has been an ideal research tool for the development of sophisticated nanobiotechnologies. Currently, the nanobody has been evolved into versatile research and application tool kits for diverse biomedical and biotechnology applications. Various nanobody-derived formats, including the nanobody itself, the radionuclide or fluorescent-labeled nanobodies, nanobody homo- or heteromultimers, nanobody-coated nanoparticles, and nanobody-displayed bacteriophages, have been successfully demonstrated as powerful nanobiotechnological tool kits for basic biomedical research, targeting drug delivery and therapy, disease diagnosis, bioimaging, and agricultural and plant protection. These applications indicate a special advantage of these nanobody-derived technologies, already surpassing the “me-too” products of other equivalent binders, such as the full-length antibodies, single-chain variable fragments, antigen-binding fragments, targeting peptides, and DNA-based aptamers. In this review, we summarize the current state of the art in nanobody research, focusing on the nanobody structural features, nanobody production approach, nanobody-derived nanobiotechnology tool kits, and the potentially diverse applications in biomedicine and biotechnology. The future trends, challenges, and limitations of the nanobody-derived nanobiotechnology tool kits are also discussed.

Advanced microscopy of star-shaped gold nanoparticles and their adsorption-uptake by macrophages

Metallic nanoparticles have diverse applications in biomedicine, as diagnostics, image contrast agents, nanosensors and drug delivery systems. Anisotropic metallic nanoparticles possess potential applications in cell imaging and therapy + diagnostics (theranostics), but controlled synthesis and growth of these anisotropic or branched nanostructures has been challenging and usually require use of high concentrations of surfactants. Star-shaped gold nanoparticles were synthesized in high yield through a seed mediated route using HEPES as a precise shape-directing capping agent. Characterization was performed using advanced electron microscopy techniques including atomic resolution TEM, obtaining a detailed characterization of nanostructure and atomic arrangement. Spectroscopy techniques showed that the particles have narrow size distribution, monodispersity and high colloidal stability, with absorbance into NIR region and high efficiency for SERS applications. Gold nanostars showed to be biocompatible and efficiently adsorbed and internalized by macrophages, as revealed by advanced FE-SEM and backscattered electron imaging techniques of complete unstained uncoated cells. Additionally, low voltage STEM and X-ray microanalysis revealed the ultra-structural location and confirmed stability of nanoparticles after endocytosis with high spatial resolution.

Virus engineering: functionalization and stabilization

Chemically and/or genetically engineered viruses, viral capsids and viral-like particles carry the promise of important and diverse applications in biomedicine, biotechnology and nanotechnology. Potential uses include new vaccines, vectors for gene therapy and targeted drug delivery, contrast agents for molecular imaging and building blocks for the construction of nanostructured materials and electronic nanodevices. For many of the contemplated applications, the improvement of the physical stability of viral particles may be critical to adequately meet the demanding physicochemical conditions they may encounter during production, storage and/or medical or industrial use. The first part of this review attempts to provide an updated general overview of the fast-moving, interdisciplinary virus engineering field; the second part focuses specifically on the modification of the physical stability of viral particles by protein engineering, an emerging subject that has not been reviewed before.

Capsosomes: Subcompartmentalizing Polyelectrolyte Capsules Using Liposomes

Next-generation therapeutic approaches are expected to rely on the engineering of multifunctional particle carriers that can mimic specific cellular functions. The key features of such particles are the semipermeable nature of the shell for communication with the external environment and multiple nanosized individual subcompartments confined within a micron-sized structurally stable scaffold for conducting specific reactions. Herein, we report the formation of capsosomes, a new class of polyelectrolyte capsules containing structurally intact liposomes as cargo. The multilayer film assembly of polyelectrolytes (poly(styrene sulfonate) (PSS) and poly(allylamine hydrochloride) (PAH)) and liposomes (50 nm 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC)) was characterized on planar substrates using quartz crystal microbalance with dissipation monitoring, and these findings were then correlated to the film growth of the polyelectrolytes and structurally intact liposomes on silica particles. Upon removal of the silica template core, stable capsosomes, containing one or two layers of intact liposomes as cargo, were obtained. This novel platform, capsosomes, which combines the advantages of two systems, liposomes and polyelectrolyte capsules, is expected to find diverse applications in biomedicine, in particular for the creation of artificial cells or organelles where the performance of reactions within a confined environment is a prerequisite.