Bioapplications of Nanomaterials.

Nanobiotechnology is known as the application of nanoscaled techniques in biology which bridges natural science to living organism for improving the quality of life of humans. Nanotechnology was first issued in 1959 and has been rapidly developed, supplying numerous benefits to basic scientific academy and to clinical application including human healthcare, specifically in cancer therapy. This chapter discusses recent advances and potentials of nanotechnology in pharmaceutics, therapeutics, biosensing, bioimaging, and gene delivery that demonstrate the multifunctionality of nanotechnology.

Synthesis and Application of Silica-Coated Quantum Dots in Biomedicine.

Quantum dots (QDs) are semiconductor nanoparticles with outstanding optoelectronic properties. More specifically, QDs are highly bright and exhibit wide absorption spectra, narrow light bands, and excellent photovoltaic stability, which make them useful in bioscience and medicine, particularly for sensing, optical imaging, cell separation, and diagnosis. In general, QDs are stabilized using a hydrophobic ligand during synthesis, and thus their hydrophobic surfaces must undergo hydrophilic modification if the QDs are to be used in bioapplications. Silica-coating is one of the most effective methods for overcoming the disadvantages of QDs, owing to silica's physicochemical stability, nontoxicity, and excellent bioavailability. This review highlights recent progress in the design, preparation, and application of silica-coated QDs and presents an overview of the major challenges and prospects of their application.

Luminescence Probes in Bio-Applications: From Principle to Practice.

Bioanalysis based on optical imaging has gained significant progress in the last few decades. Luminescence probes are capable of detecting, monitoring, and tracing particular biomolecules in complex biological systems to figure out the roles of these molecules in organisms. Considering the rapid development of luminescence probes for bio-applications and their promising future, we have attempted to explore the working principles and recent advances in bio-applications of luminescence probes, in the hope of helping readers gain a detailed understanding of luminescence probes developed in recent years. In this review, we first focus on the current widely used luminescence probes, including fluorescence probes, bioluminescence probes, chemiluminescence probes, afterglow probes, photoacoustic probes, and Cerenkov luminescence probes. The working principles for each type of luminescence probe are concisely described and the bio-application of the luminescence probes is summarized by category, including metal ions detection, secretion detection, imaging, and therapy.

Fine-Tuning Electron Transfer for Nanozyme Design.

Nanozymes, with their versatile composition and structural adaptability, present distinct advantages over natural enzymes including heightened stability, customizable catalytic activity, cost-effectiveness, and simplified synthesis process, making them as promising alternatives in various applications. Recent advancements in nanozyme research have shifted focus from serendipitous discovery toward a more systematic approach, leveraging machine learning, theoretical calculations, and mechanistic explorations to engineer nanomaterial structures with tailored catalytic functions. Despite its pivotal role, electron transfer, a fundamental process in catalysis, has often been overlooked in previous reviews. This review comprehensively summarizes recent strategies for modulating electron transfer processes to fine-tune the catalytic activity and specificity of nanozymes, including electron-hole separation and carrier transfer. Furthermore, the bioapplications of these engineered nanozymes, including antimicrobial treatments, cancer therapy, and biosensing are also introduced. Ultimately, this review aims to offer invaluable insights for the design and synthesis of nanozymes with enhanced performance, thereby advancing the field of nanozyme research.

Photofunctional Gold Nanocluster Composites for Bioapplications.

Gold nanoclusters (AuNCs), with customized structures and diverse optical properties, are promising optical materials. Constructing composite systems by the assembly and incorporation of AuNCs can utilize their optical properties to achieve diagnostic and therapeutic applications in the biological field. Therefore, the exploration of the assembly behaviors of AuNCs and the enhancement of their performance has attracted widespread interest. In this review, we introduce multiple interactions and assembly modes that are prevalent in nanocomposites and microcomposites based on AuNCs. Then, the functions of AuNC composites for bioapplications are demonstrated in detail. These composite systems have inherited and enhanced the inherent optical performances of the AuNCs to meet diverse requirements for biological sensing and optical treatments. Finally, we discuss the prospects of AuNC composites and highlight the challenges and opportunities in biomedical applications.

Silver-enriched microdomain patterns as advanced bactericidal coatings for polymer-based medical devices.

Today, it would be difficult for us to live a full life without polymers, especially in medicine, where its applicability is constantly expanding, giving satisfactory results without any harm effects on health. This study focused on the formation of hexagonal domains doped with AgNPs using a KrF excimer laser (λ=248 nm) on the polyetheretherketone (PEEK) surface that acts as an unfailing source of the antibacterial agent - silver. The hexagonal structure was formed with a grid placed in front of the incident laser beam. Surfaces with immobilized silver nanoparticles (AgNPs) were observed by AFM and SEM. Changes in surface chemistry were studied by XPS. To determine the concentration of released Ag+ ions, ICP-MS analysis was used. The antibacterial tests proved the antibacterial efficacy of Ag-doped PEEK composites against Escherichia coli and Staphylococcus aureus as the most common pathogens. Because AgNPs are also known for their strong toxicity, we also included cytotoxicity tests in this study. The findings presented here contribute to the advancement of materials design in the biomedical field, offering a novel starting point for combating bacterial infections through the innovative integration of AgNPs into inert synthetic polymers.

Structural properties, bioactivities, structure-activity relationships and bio-applications of polysaccharides from Auricularia auricula: A review.

Auricularia auricula (A. auricula), is a medicinal and edible fungus in China for thousands of years with rich nutrition and delicious taste. The main active ingredient of A. auricula is polysaccharide, which has antitumor, hypoglycemic, antioxidant, and immune regulation bioactivities. It is widely recognized that the biological activity of polysaccharides is closely related to the chemical structure and advanced structure. In terms of polysaccharides extracted from A. auricula (AAPs), there were distinguished structures reported due to the different original resources and extraction methods, leading to various bioactivities. However, the structure-activity relationship of AAPs has scarcely been reviewed till now. In addition, polysaccharides were found to have specific self-assembly properties recently, together with their bioactivities, endowing them with unique physicochemical properties. Nowadays, an increasing number of polysaccharides, such as cellulose, chitin, and pectin, have been used to construct various functional materials in the fields of food, cosmetics, and biomedical materials. Therefore, the construction of functional materials by AAPs is of great research significance. This article aims to provide a systematic review of the structure-activity relationship of AAPs and summarize the functional materials constructed based on AAPs to provide theoretical references for further research and application of AAPs.

Recent advances in MOF-based nanozymes: Synthesis, activities, and bioapplications.

Nanozymes have garnered considerable research interest for their unique capacity to bridge nanotechnology and biology. Current studies predominantly concentrate on exploring nanozymes with diverse catalytic activities and their potential applications across various disciplines. Among them, nanoscale metal-organic frameworks (MOFs) are promising nanomaterials for constructing nanozymes. In this review, we firstly introduce the general construction strategies for MOF-based nanozymes. In addition, we also classify the MOF-based nanozymes in detail based on their catalytic performance. Thirdly, the recent research progress of MOF-based nanozymes in the field of biosensing, cancer therapy, antibacterial infection, and antioxidation are also comprehensively reviewed. Finally, we discuss the current challenges and future perspectives of MOF-based nanozymes, with the aim of assisting in their construction and maximizing their potential in bioapplications. It is hoped that we could provide scientists in materials science and biomedical research with valuable and comprehensive information, fostering advancements in interdisciplinary fields.

Recent Studies on Metal-Embedded Silica Nanoparticles for Biological Applications.

Recently, silica nanoparticles (NPs) have attracted considerable attention as biocompatible and stable templates for embedding noble metals. Noble-metal-embedded silica NPs utilize the exceptional optical properties of novel metals while overcoming the limitations of individual novel metal NPs. In addition, the structure of metal-embedded silica NPs decorated with small metal NPs around the silica core results in strong signal enhancement in localized surface plasmon resonance and surface-enhanced Raman scattering. This review summarizes recent studies on metal-embedded silica NPs, focusing on their unique designs and applications. The characteristics of the metal-embedded silica NPs depend on the type and structure of the embedded metals. Based on this progress, metal-embedded silica NPs are currently utilized in various spectroscopic applications, serving as nanozymes, detection and imaging probes, drug carriers, photothermal inducers, and bioactivation molecule screening identifiers. Owing to their versatile roles, metal-embedded silica NPs are expected to be applied in various fields, such as biology and medicine, in the future.

Application and Development Prospect of Nanoscale Iron Based Metal-Organic Frameworks in Biomedicine.

Metal-organic frameworks (MOFs) are coordination polymers that comprise metal ions/clusters and organic ligands. MOFs have been extensively employed in different fields (eg, gas adsorption, energy storage, chemical separation, catalysis, and sensing) for their versatility, high porosity, and adjustable geometry. To be specific, Fe2+/Fe3+ exhibits unique redox chemistry, photochemical and electrical properties, as well as catalytic activity. Fe-based MOFs have been widely investigated in numerous biomedical fields over the past few years. In this study, the key index requirements of Fe-MOF materials in the biomedical field are summarized, and a conclusion is drawn in terms of the latest application progress, development prospects, and future challenges of Fe-based MOFs as drug delivery systems, antibacterial therapeutics, biocatalysts, imaging agents, and biosensors in the biomedical field.

Structural and photoactive properties of self-assembled peptide-based nanostructures and their optical bioapplication in food analysis.

BACKGROUND: Food processing plays an important role in the modern industry because food quality and security directly affect human health, life safety, and social and economic development. Accurate, efficient, and sensitive detection technology is the basis for ensuring food quality and security. Optosensor-based technology with the advantage of fast and visual real-time detection can be used to detect pesticides, metal ions, antibiotics, and nutrients in food. As excellent optical centres, self-assembled peptide-based nanostructures possess attractive advantages, such as simple preparation methods, controllable morphology, tunable functionality, and inherent biocompatibility. AIM OF REVIEW: Self-assembled peptide nanostructures with good fabrication yield, stability, dispersity in a complex sample matrix, biocompatibility, and environmental friendliness are ideal development goals in the future. Owing to its flexible and unique optical properties, some short peptide self-assemblies can possibly be used to achieve the purpose of rapid and sensitive detection of composition in food, agriculture, and the environment, expanding the understanding and application of peptide-based optics in analytical chemistry. KEY SCIENTIFIC CONCEPT OF REVIEW: The self-assembly process of peptides is driven by noncovalent interactions, including hydrogen bonding, electrostatic interactions, hydrophobic interactions, and π-π stacking, which are the key factors for obtaining stable self-assembled peptide nanostructures with peptides serving as assembly units. Controllable morphology of self-assembled peptide nanostructures can be achieved through adjustment in the type, concentration, and pH of organic solvents and peptides. The highly ordered nanostructures formed by the self-assembly of peptides have been proven to be novel biological structures and can be used for the construction of optosensing platforms in biological or other systems. Optosensing platforms make use of signal changes, including optical signals and electrical signals caused by specific reactions between analytes and active substances, to determine the content or concentration of an analyte.

Recent Advances in Kaolinite Nanoclay as Drug Carrier for Bioapplications: A Review.

Advanced functional two-dimensional (2D) nanomaterials offer unique advantages in drug delivery systems for disease treatment. Kaolinite (Kaol), a nanoclay mineral, is a natural 2D nanomaterial because of its layered silicate structure with nanoscale layer spacing. Recently, Kaol nanoclay is used as a carrier for controlled drug release and improved drug dissolution owing to its advantageous properties such as surface charge, strong biocompatibility, and naturally layered structure, making it an essential development direction for nanoclay-based drug carriers. This review outlines the main physicochemical characteristics of Kaol and the modification methods used for its application in biomedicine. The safety and biocompatibility of Kaol are addressed, and details of the application of Kaol as a drug delivery nanomaterial in antibacterial, anti-inflammatory, and anticancer treatment are discussed. Furthermore, the challenges and prospects of Kaol-based drug delivery nanomaterials in biomedicine are discussed. This review recommends directions for the further development of Kaol nanocarriers by improving their physicochemical properties and expanding the bioapplication range of Kaol.

Preparation of Fluorescent Carbon Dots Composites and Their Potential Applications in Biomedicine and Drug Delivery-A Review.

Carbon dots (CDs), a new member of carbon nanostructures, rely on surface modification and functionalization for their good fluorescence phosphorescence and excellent physical and chemical properties, including small size (<10 nm), high chemical stability, biocompatibility, non-toxicity, low cost, and easy synthesis. In the field of medical research on cancer (IARC), CDs, a new material with unique optical properties as a photosensitizer, are being applied to heating local apoptosis induction of cancer cells. In addition, imaging tools can also be combined with a drug to form the nanometer complex compound, the imaging guidance for multi-function dosage, so as to improve the efficiency of drug delivery, which also plays a big role in genetic diagnosis. This paper mainly includes three parts: The first part briefly introduces the synthesis and preparation of carbon dots, and summarizes the advantages and disadvantages of different preparation methods; The second part introduces the preparation methods of carbon dot composites. Finally, the application status of carbon dot composites in biomedicine, cancer theranostics, drug delivery, electrochemistry, and photocatalysis is summarized.

Synthesis, determination, and bio-application in cellular and biomass-bamboo imaging of natural cinnamaldehyde derivatives.

Cinnamon essential oil (CEO) is the main ingredient in the renewable biomass of cinnamon, which contains natural cinnamaldehyde. To valorize the value of cinnamaldehyde, two simple and useful compounds (1 and 2) from CEO were synthesized using a Schiff-base reaction and characterized by infrared spectra (IR), nuclear magnetic resonance (NMR), and high-resolution mass spectrometry (HRMS). Compound 1 was used to confirm the presence of Fe3+ and ClO- in solution, as well as compound 2. Using fluorescence enhancement phenomena, it offered practicable linear relationship of 1's fluorescence intensity and Fe3+ concentrations: (0-8.0 × 10-5 mol/L), y = 36.232x + 45.054, R 2 = 0.9947, with a limit of detection (LOD) of 0.323 µM, as well as compound 2. With increasing fluorescence, F404/F426 of 1 and the ClO- concentration (0-1.0 × 10-4 mol/L) also had a linear relationship: y = 0.0392x + 0.5545, R 2 = 0.9931, LOD = 0.165 µM. However, the fluorescence intensity of 2 (596 nm) was quenched by a reduced concentration of ClO-, resulting in a linear. In addition, compounds 1 and 2 were used to image human astrocytoma MG (U-251), brain neuroblastoma (LN-229) cells, and bamboo tissue by adding Fe3+ or ClO-, with clear intracellular fluorescence. Thus, the two compounds based on CEO could be used to dye cells and bamboo tissues by fluorescence technology.

The preparation technology and application of xylo-oligosaccharide as prebiotics in different fields: A review.

Xylo-oligosaccharide (XOS) is a class of functional oligosaccharides that have been demonstrated with prebiotic activity over several decades. XOS has several advantages relative to other oligosaccharide molecules, such as promoting root development as a plant regulator, a sugar supplement for people, and prebiotics to promote intestinal motility utilization health. Now, the preparation and extraction process of XOS is gradually mature, which can maximize the extraction and avoid waste. To fully understand the recent preparation and application of XOS in different areas, we summarized the various technologies for obtaining XOS (including acid hydrolysis, enzymatic hydrolysis, hydrothermal pretreatment, and alkaline extraction) and current applications of XOS, including in animal feed, human food additives, and medicine. It is hoped that this review will serve as an entry point for those looking into the prebiotic field of research, and perhaps begin to dedicate their work toward this exciting classification of bio-based molecules.

Cationic gemini surfactant properties, its potential as a promising bioapplication candidate, and strategies for improving its biocompatibility: A review.

Gemini surfactants consist of two cationic monomers of a surfactant linked together with a spacer. The specific structure of a cationic gemini surfactant is the reason for both its high surface activity and its ability to decrease the surface tension of water. The high surface activity and unique structure of gemini surfactants result in outstanding properties, including antibacterial and antifungal activity, anticorrosion properties, unique aggregation behaviour, the ability to form various structures reversibly in response to environmental conditions, and interactions with biomacromolecules such as DNA and proteins. These properties can be tailored by selecting the optimal structure of a gemini surfactant in terms of the nature and length of its alkyl substituents, spacer, and head group. Additionally, regarding their properties, comparison with their monomeric counterparts demonstrates that gemini surfactants have higher performance efficacy at lower concentrations. Hence, less material is needed, and the toxicity is lower. However, there are some limitations regarding their biocompatibility that have led researchers to develop amino acid-based and sugar-based gemini surfactants. Owing to their remarkable properties, cationic gemini surfactants are promising candidates for bioapplications such as drug delivery systems, gene carriers, and biomaterial surface modification.

Advances in plasmonic-based MOF composites, their bio-applications, and perspectives in this field.

INTRODUCTION: Nanomaterials have been used for bio-applications since the late twentieth century. In an attempt to tailor and optimize their properties, and by extension their efficiency, composites have attracted considerable attention. In this regard, recent studies on plasmonic nanoparticles and metal-organic framework (NP@MOF) composites suggest that these materials show great promise in this field. AREAS COVERED: This review focused on the more recent scientific advances in the synthetic strategies to optimize plasmonic MOF nanocomposites currently available, as well as their bio-application, particularly as biosensors and in therapy. EXPERT OPINION: Plasmonic MOF nanocomposites have shown a great potential as they combine the properties of both materials with proven efficiency in bio-application. On the one hand, nanoMOFs have proven their potential particularly as drug nanocarriers, owing to their exceptional porosity and tunability. On the other hand, plasmonic nanoparticles have been an asset for imaging and phototherapy. Different strategies have been reported to develop these nanocomposites, mainly including core-shell, encapsulation, and in situ reduction. In addition, advanced composite structures should be considered, such as mixed metal nanoparticles, hollow structures, or the combination of several approaches. Specifically, plasmonic MOF nanocomposites prove to be attractive stimuli-responsive drug delivery systems, phototherapeutic agents, and highly sensitive biosensors. [Figure: see text].

Engineering Red-Enhanced and Biocompatible Upconversion Nanoparticles.

The exceptional optical properties of lanthanide-doped upconversion nanoparticles (UCNPs) make them among the best fluorescent markers for many promising bioapplications. To fully utilize the unique advantages of the UCNPs for bioapplications, recent significant efforts have been put into improving the brightness of small UCNPs crystals by optimizing dopant concentrations and utilizing the addition of inert shells to avoid surface quenching effects. In this work, we engineered bright and small size upconversion nanoparticles in a core-shell-shell (CSS) structure. The emission of the synthesized CSS UCNPs is enhanced in the biological transparency window under biocompatible excitation wavelength by optimizing dopant ion concentrations. We also investigated the biosafety of the synthesized CSS UCNP particles in living cell models to ensure bright and non-toxic fluorescent probes for promising bioapplications.

Synthesis of Polyhedral Metal-Organic Framework@Mesoporous Silica Hybrid Nanocomposites with Branched Shapes.

The structural modulation of multicompartment porous nanomaterials is one of the major challenges of nanoscience. Herein, by utilizing the polyhedral effects/characteristics of metal-organic frameworks (MOFs), we present a versatile approach to construct MOF-organosilica hybrid branched nanocomposites with MOF cores, SiO2 shells, and periodic mesoporous organosilica (PMO) branches. The morphology, structure, and functions of the obtained hybrid nanocomposites can be facilely modulated by varying particle size, shape, or crystalline structures of the MOF cores. Specifically, these branched multicompartment porous nanoparticles exhibit evasion behaviors in epithelial cells compared with macrophage cells, which may endow them great potential as a vehicle for immunotherapy.

Photostable and Small YVO4:Yb,Er Upconversion Nanoparticles in Water.

In this work, we report a simple method of silica coating of upconversion nanoparticles (UCNPs) to obtain well-crystalline particles that remain small and not agglomerated after high-temperature post-annealing, and produce bright visible emission when pumped with near-infrared light. This enables many interesting biological applications, including high-contrast and deep tissue imaging, quantum sensing and super-resolution microscopy. These VO4-based UNCPs are an attractive alternative to fluoride-based crystals for water-based biosensing applications.