Advances in drug delivery-based therapeutic strategies for renal fibrosis treatment.

Renal fibrosis is the result of all chronic kidney diseases and is becoming a major global health hazard. Currently, traditional treatments for renal fibrosis are difficult to meet clinical needs due to shortcomings such as poor efficacy or highly toxic side effects. Therefore, therapeutic strategies that target the kidneys are needed to overcome these shortcomings. Drug delivery can be attained by improving drug stability and addressing controlled release and targeted delivery of drugs in the delivery category. By combining drug delivery technology with nanosystems, controlled drug release and biodistribution can be achieved, enhancing therapeutic efficacy and reducing toxic cross-wise effects. This review discusses nanomaterial drug delivery strategies reported in recent years. Firstly, the present review describes the mechanisms of renal fibrosis and anti-renal fibrosis drug delivery. Secondly, different nanomaterial drug delivery strategies for the treatment of renal injury and fibrosis are highlighted. Finally, the limitations of these strategies are also discussed. Investigating various anti-renal fibrosis drug delivery strategies reveals the characteristics and therapeutic effects of various novel nanosystem-derived drug delivery approaches. This will serve as a reference for future research on drug delivery strategies for renal fibrosis treatment.

Metal-organic frameworks for biomedical applications: A review.

Metal-organic frameworks (MOFs) are emergent materials in diverse prospective biomedical uses, owing to their inherent features such as adjustable pore dimension and volume, well-defined active sites, high surface area, and hybrid structures. The multifunctionality and unique chemical and biological characteristics of MOFs allow them as ideal platforms for sensing numerous emergent biomolecules with real-time monitoring towards the point-of-care applications. This review objects to deliver key insights on the topical developments of MOFs for biomedical applications. The rational design, preparation of stable MOF architectures, chemical and biological properties, biocompatibility, enzyme-mimicking materials, fabrication of biosensor platforms, and the exploration in diagnostic and therapeutic systems are compiled. The state-of-the-art, major challenges, and the imminent perspectives to improve the progressions convoluted outside the proof-of-concept, especially for biosensor platforms, imaging, and photodynamic therapy in biomedical research are also described. The present review may excite the interdisciplinary studies at the juncture of MOFs and biomedicine.

MOF-Based Platform for Kidney Diseases: Advances, Challenges, and Prospects.

Kidney diseases are important diseases that affect human health worldwide. According to the 2020 World Health Organization (WHO) report, kidney diseases have become the top 10 causes of death. Strengthening the prevention, primary diagnosis, and action of kidney-related diseases is of great significance in maintaining human health and improving the quality of life. It is increasingly challenging to address clinical needs with the present technologies for diagnosing and treating renal illness. Fortunately, metal-organic frameworks (MOFs) have shown great promise in the diagnosis and treatment of kidney diseases. This review summarizes the research progress of MOFs in the diagnosis and treatment of renal disease in recent years. Firstly, we introduce the basic structure and properties of MOFs. Secondly, we focus on the utilization of MOFs in the diagnosis and treatment of kidney diseases. In the diagnosis of kidney disease, MOFs are usually designed as biosensors to detect biomarkers related to kidney disease. In the treatment of kidney disease, MOFs can not only be used as an effective adsorbent for uremic toxins during hemodialysis but also as a precise treatment of intelligent drug delivery carriers. They can also be combined with nano-chelation technology to solve the problem of the imbalance of trace elements in kidney disease. Finally, we describe the current challenges and prospects of MOFs in the diagnosis and treatment of kidney diseases.

Ni(OH)2 nanosheets decorated with FeCoPi on NiO heterostructures: tunable intrinsic electronic structures for improved overall water splitting.

Herein, we demonstrate the rational design of 3-dimensional nickel double hydroxide nanosheets decorated with iron-cobalt phosphide on nickel oxide (Ni(OH)2@FexCo1-xPi|NiO) heterostructures for achieving improved overall water splitting. The as-optimized Ni(OH)2@FexCo1-xPi|NiO heterostructures exhibited an overpotential (η) of ∼133 mV and ∼173 mV at 10 mA cm-2 for the oxygen evolution reaction (OER) and the hydrogen evolution reaction (HER), respectively, in an alkaline electrolyte through a tunable electronic interaction and stabilization of the active Ni(OH)2 and FeCoPi interface.

Enzyme-free electrochemical sensor platforms based on transition metal nanostructures for clinical diagnostics.

The detection of emergent biomarkers is of key significance in numerous clinical, biological, and biomedical fields. Specifically, the design and development of potent electrochemical lactic acid and glucose sensing platforms are especially in great demand in a variety of industries, including those involved in clinical analysis, biomedicine, biological, food, cosmetics, pharmaceuticals, leather, sports, and chemical industries. Nanostructured transition metal-derived materials have opened the door to electrochemical sensors and biosensors due to their advantages of high surface-to-volume ratio, surface reaction activity, catalytic activity, and strong adsorption capability. The primary aim of the present minireview is to highlight the advancement of enzyme-free electrochemical sensor platforms based on transition metal-derived nanostructures with high electrocatalytic activity and sensing performance towards lactic acid and glucose in practical samples. The preparation approaches, structural and composition monitoring, fabrication of sensing electrodes, catalytic activity, sensing performance in real samples, and the exploration of sensing mechanisms are majorly concentrated on in most of our recent research studies. Moreover, state-of-the-art transition metal-derived nanostructure-derived electrochemical sensor platforms, critical comparison of the analytical performance of the sensor platforms, and the future perspectives of the enzyme-free electrochemical sensor for clinical diagnostics are described.

Metal Oxides Nanomaterials and Nanocomposite-Based Electrochemical Sensors for Healthcare Applications.

Wide-ranging research efforts have been directed to prioritize scientific and technological inventions for healthcare monitoring. In recent years, the effective utilization of functional nanomaterials in various electroanalytical measurements realized a rapid, sensitive, and selective detection and monitoring of a wide range of biomarkers in body fluids. Owing to good biocompatibility, high organic capturing ability, strong electrocatalytic activity, and high robustness, transition metal oxide-derived nanocomposites have led to enhancements in sensing performances. The aim of the present review is to describe key advancements of transition metal oxide nanomaterials and nanocomposites-based electrochemical sensors, along with current challenges and prospects towards the development of a highly durable and reliable detection of biomarkers. Moreover, the preparation of nanomaterials, electrode fabrication, sensing mechanism, electrode-bio interface, and performance of metal oxides nanomaterials and nanocomposite-based sensor platforms will be described.

Carbon Nanocomposites-Based Electrochemical Sensors and Biosensors for Biomedical Diagnostics.

Detection of emergent biomolecules or biomarkers remains crucial for early diagnosis in advancing healthcare monitoring and biomedicine. The possibility for rapid detection, real-time monitoring, high sensitivity, low detection limit, good selectivity, and low cost is central, among other significant issues for advancing point-of-care diagnosis. Carbon-based nanocomposites have been employed as sensing materials for various biomarkers due to their high surface-to-volume ratio, high electrical conductivity, chemical stability, and biocompatibility. The carbon nanomaterials, such as carbon nanotubes (CNTs), graphene (GR), carbon quantum dots (CQDs), carbon fibres (CFs), and their nanocomposites have broadly integrated with numerous sensing electrode materials for the detection of biomarkers under various experimental settings. The present review includes the recent advances in the development of carbon nanomaterials-based electrochemical sensors and biosensors for biomedical applications. The preparation, electrode preparation, effective utilization of carbon-derived nanomaterials, and their sensing performances towards numerous biomarkers have been highlighted. The state-of-the-merit, challenges, and prospects for designing carbon nanocomposites-based electrochemical sensor/biosensor platforms for biomedical diagnostics have also been described.

FeCoP nanosheets on NiO nanoparticles as electrocatalysts: tuning and stabilizing active sites for water splitting.

Herein, we demonstrate a novel strategy for tailoring and stabilizing the interface of active sites on hierarchical three-dimensional (3D) iron-cobalt phosphide (Fe1-xCoxP) nanosheets on nickel oxide nanoparticles for overall water splitting. The developed bifunctional electrode required an overpotential of only ∼158 mV and ∼74 mV to attain 10 mA cm-2 for oxygen evolution and hydrogen evolution reactions, respectively, with excellent durability over 100 h in 1.0 M KOH via engineering interfacial active sites, revealing the progress in the development of electrocatalytic activity.

Nanostructured Transition Metal Sulfide-based Glucose and Lactic Acid Electrochemical Sensors for Clinical Applications.

Engineered nanostructures of mixed transition metal sulfides have emerged as promising nanomaterials (NMs) for various electrochemical sensors and biosensors applications, including glucose sensors (GS) and lactic acid sensors (LAS) in clinical aspects. Electrochemical sensors based on nanostructured materials, such as transition metal sulfides and their nanocomposites, including graphene, carbon nanotubes, molecularly imprinted polymers, and metal-organic frameworks, have emerged as potent tools for the monitoring and quantification of biomolecules. Highly sensitive and selective electrochemical detection systems have generally been established credibly by providing new functional surfaces, miniaturization processes, and different nanostructured materials with exceptional characteristics. This review provides an overview of glucose and lactic acid sensors based on transition metal nanomaterials and their nanocomposites with a detailed discussion about the advantages and challenges. The merits of nanoscale transition metal sulphide-based electrochemical sensors and biosensor systems include cost-effectiveness, ease of miniaturization process, energy- and time-efficient, simple preparation, etc. Moreover, online sensing competence is the dynamic strength for sustained progress of electrochemical detection systems, thus fascinating interdisciplinary research. In particular, we discuss the synthesis, characteristics, electrode construction strategies, and uses in electrochemical sensing of glucose and lactic acid primarily based on our most recent research and other reports. In addition, the challenges and future perspectives of the nanostructured transition metal sulfides-based electrochemical sensing and biosensing systems toward the detection of glucose and lactic acid are described.

Gold Nanoclusters Dispersed on Gold Dendrite-Based Carbon Fibre Microelectrodes for the Sensitive Detection of Nitric Oxide in Human Serum.

Herein, gold nanoclusters (Au NC) dispersed on gold dendrite (Au DS)-based flexible carbon fibre (AuNC@AuDS|CF) microelectrodes are developed using a one-step electrochemical approach. The as-fabricated AuNC@AuDS|CF microelectrodes work as the prospective electrode materials for the sensitive detection of nitric oxide (NO) in a 0.1 M phosphate buffer (PB) solution. Carbon microfibre acts as an efficient matrix for the direct growth of AuNC@AuDS without any binder/extra reductant. The AuNC@AuDS|CF microelectrodes exhibit outstanding electrocatalytic activity towards NO oxidation, which is ascribed to their large electrochemical active surface area (ECSA), high electrical conductivity, and high dispersion of Au nanoclusters. As a result, the AuNC@AuDS|CF microelectrodes attain a rapid response time (3 s), a low limit of detection (LOD) (0.11 nM), high sensitivity (66.32 µA µM cm-2), a wide linear range (2 nM-7.7 µM), long-term stability, good reproducibility, and a strong anti-interference capability. Moreover, the present microsensor successfully tested for the discriminating detection of NO in real human serum samples, revealing its potential practicability.

Gold-dispersed hierarchical flower-like copper oxide microelectrodes for the sensitive detection of glucose and lactic acid in human serum and urine.

Herein, we report self-supported gold-dispersed copper oxide microflowers (Au@CuO MFs) on copper microelectrodes (CMEs) as a sensitive platform for the sensing of glucose and lactic acid in human serum and urine samples. The direct growth of a new class of gold-dispersed copper oxide microflowers on Cu microelectrodes involves growing flower-like passivated copper microelectrodes in nitric acid followed by the galvanic replacement of copper atoms with gold atoms without employing any surfactant or polymer or without the use of any catalysts or complicated procedures. The as-fabricated gold-dispersed copper oxide microflower microelectrodes (Au@CuO MFs|CME) were employed as potential signal transducers for the sensitive detection of glucose and lactic acid in practical samples. The present Au@CuO MFs|CME microsensor demonstrates an extensive linear detection range from 5.0 µM to 0.5 mM for glucose with a low limit of detection (LOD) of ∼1.41 µM and a sensitivity of ∼4.14 mA µM-1 cm-2, and from 100 nM to 88.0 µM for lactic acid with a LOD of ∼27.0 nM and a sensitivity of ∼6.19 mA µM-1 cm-2. The present multi-functional nanoarchitectured Au@CuO MFs|CME microsensor is anticipated to offer unique surface characteristics and synergistic effects, and can be exploited in various electrochemical fields.

Iron sulphide rice grain nanostructures as potential electrocatalysts for an improved oxygen evolution reaction.

Iron based chalcogenides are considered a promising group of electro-active materials for various electrochemical technologies. Herein we demonstrate a facile fabrication of various iron sulphide (FeS) nanostructures, including rice grains (RGS)-, nanoflowers (NFS)- and nanoparticles (NPS)-like surface morphologies via electrochemical, solvothermal and chemical strategies, respectively. The as-developed FeS nanostructures have been employed as electrocatalysts for the oxygen evolution reaction (OER) in an alkaline electrolyte. Among other FeS nanostructures, FeS rice grains (FeS-RGS) exhibited an outstanding OER activity with a low onset potential (∼1.37 V), low overpotential (∼0.20 V), small Tafel slope (∼54.2 mV dec-1), high mass activity (∼5.4 A g-1), and high durability, outperforming the commercial state-of-the-art RuO2 catalyst. The high-performance OER activity of the FeS-RGS is associated not only to the synergistic effect of Fe and S, but also to the direct growth (binder-free) and edges of rice grain structures, offering a large number of electrochemical active sites and ensuring fast-diffusion of OH- ions of the nanostructures. The present one-step, low-cost and highly scalable preparation of FeS-RGS nanostructures provides new possibilities of morphology and synthetic methodology dependence of OER electrocatalysts for effective hydrogen production.

Non-Enzymatic Glucose Detection Based on NiS Nanoclusters@NiS Nanosphere in Human Serum and Urine.

Herein, we report a non-enzymatic electrochemical glucose sensing platform based on NiS nanoclusters dispersed on NiS nanosphere (NC-NiS@NS-NiS) in human serum and urine samples. The NC-NiS@NS-NiS are directly grown on nickel foam (NF) (NC-NiS@NS-NiS|NF) substrate by a facile, and one-step electrodeposition strategy under acidic solution. The as-developed nanostructured NC-NiS@NS-NiS|NF electrode materials successfully employ as the enzyme-mimic electrocatalysts toward the improved electrocatalytic glucose oxidation and sensitive glucose sensing. The NC-NiS@NS-NiS|NF electrode presents an outstanding electrocatalytic activity and sensing capability towards the glucose owing to the attribution of great double layer capacitance, excessive electrochemical active surface area (ECASA), and high electrochemical active sites. The present sensor delivers a limit of detection (LOD) of ~0.0083 µM with a high sensitivity of 54.6 µA mM-1 cm-2 and a wide linear concentration range (20.0 µM-5.0 mM). The NC-NiS@NS-NiS|NF-based sensor demonstrates the good selectivity against the potential interferences and shows high practicability by glucose sensing in human urine and serum samples.

Bimetallic Nanomaterials-Based Electrochemical Biosensor Platforms for Clinical Applications.

Diabetes is a foremost health issue that results in ~4 million deaths every year and ~170 million people suffering globally. Though there is no treatment for diabetes yet, the blood glucose level of diabetic patients should be checked closely to avoid further problems. Screening glucose in blood has become a vital requirement, and thus the fabrication of advanced and sensitive blood sugar detection methodologies for clinical analysis and individual care. Bimetallic nanoparticles (BMNPs) are nanosized structures that are of rising interest in many clinical applications. Although their fabrication shares characteristics with physicochemical methodologies for the synthesis of corresponding mono-metallic counterparts, they can display several interesting new properties and applications as a significance of the synergetic effect between their two components. These applications can be as diverse as clinical diagnostics, anti-bacterial/anti-cancer treatments or biological imaging analyses, and drug delivery. However, the exploitation of BMNPs in such fields has received a small amount of attention predominantly due to the vital lack of understanding and concerns mainly on the usage of other nanostructured materials, such as stability and bio-degradability over extended-time, ability to form clusters, chemical reactivity, and biocompatibility. In this review article, a close look at bimetallic nanomaterial based glucose biosensing approaches is discussed, concentrating on their clinical applications as detection of glucose in various real sample sources, showing substantial development of their features related to corresponding monometallic counterparts and other existing used nanomaterials for clinical applications.

Hollow sphere nickel sulfide nanostructures-based enzyme mimic electrochemical sensor platform for lactic acid in human urine.

An enzyme-free electrochemical sensor platform is reported based on hollow sphere structured nickel sulfide (HS-NiS) nanomaterials for the sensitive lactic acid (LA) detection in human urine. Hollow sphere nickel sulfide nanostructures directly grow on the nickel foam (NiF) substrate by using facile and one-step electrochemical deposition strategy towards the electrocatalytic lactic acid oxidation and sensing for the first time. The as-developed nickel sulfide nanostructured electrode (NiF/HS-NiS) has been successfully employed as the enzyme mimic electrode towards the enhanced electrocatalytic oxidation and detection of lactic acid. The NiF/HS-NiS electrode exhibits an excellent electrocatalytic activity and sensing ability with low positive potential (~ 0.52 V vs Ag/AgCl), catalytic current density (~ 1.34 mA), limit of detection (LOD) (0.023 µM), linear range from 0.5 to 88.5 µM with a correlation coefficient of R2 = 0.98, sensitivity (0.655 µA µM-1 cm-2), and selectivity towards the lactic acid owing to the ascription of high inherent electrical conductivity, large electrochemical active surface area (ECASA), high electrochemical active sites, and strong adsorption ability. The sensors developed in this work demonstrate the selectivity against potential interferences, including uric acid (UA), ascorbic acid (AA), paracetamol (PA), Mg2+, Na+, and Ca2+. Furthermore, the developed sensors show practicability by sensing lactic acid in human urine samples, suggesting that the HS-NiS nanostructures device has promising clinical diagnostic potential. Graphical abstract.

Two-Dimensional Earth-Abundant Transition Metal Oxides Nanomaterials: Synthesis and Application in Electrochemical Oxygen Evolution Reaction.

Development of a universal synthetic strategy for two-dimensional (2D) Earth-abundant transition metal oxides nanomaterials is highly vital toward numerous electrochemical applications. Herein, a facile and general synthesis of highly ordered two-dimensional metal oxides nanomaterials includes Co3O4, NiO, CuO, and Fe3O4 nanosheets as an electrocatalyst for oxygen evolution reaction (OER) is demonstrated. Among the synthesized 2D transition metal oxides, the Co3O4 nanosheet exhibits smallest overpotential (η) of ∼384.0 mV at a current density of 10.0 mA cm-2 and Tafel slope of ∼52.0 mV dec-1, highest mass activity of ∼112.3 A g-1 at the overpotential of ∼384.0 mV, and high turn over frequency (TOF) of 0.099 s-1, which is relatively favorable with state-of-the-art RuO2 catalyst. The present synthetic approach may unlock a brand new pathway to prepare shape-controlled Earth-abundant transition metal oxides nanomaterials for electrocatalytic OER.

Electrochemical sensor and biosensor platforms based on advanced nanomaterials for biological and biomedical applications.

Introduction of novel functional nanomaterials and analytical technologies signify a foremost possibility for the advance of electrochemical sensor and biosensor platforms/devices for a broad series of applications including biological, biomedical, biotechnological, clinical and medical diagnostics, environmental and health monitoring, and food industries. The design of sensitive and selective electrochemical biological sensor platforms are accomplished conceivably by offering new surface modifications, microfabrication techniques, and diverse nanomaterials with unique properties for in vivo and in vitro medical analysis via relating a sensibly planned electrode/solution interface. The advantageous attributes such as low-cost, miniaturization, energy efficient, easy fabrication, online monitoring, and the simultaneous sensing capability are the driving force towards continued growth of electrochemical biosensing platforms, which have fascinated the interdisciplinary research arenas spanning chemistry, material science, biological science, and medical industries. The electrochemical biosensor platforms have potential applications in the early-stage detection and diagnosis of disease as stout and tunable diagnostic and therapeutic systems. The key aim of this review is to emphasize the newest development in the design of sensing and biosensing platforms based on functional nanomaterials for biological and biomedical applications. High sensitivity and selectivity, fast response, and excellent durability in biological media are all critical aspects which will also be wisely addressed. Potential applications of electrochemical sensor and biosensor platforms based on advanced functional nanomaterials for neuroscience diagnostics, clinical, point-of-care diagnostics and medical industries are also concisely presented.

Hierarchical oxygen-implanted MoS2 nanoparticle decorated graphene for the non-enzymatic electrochemical sensing of hydrogen peroxide in alkaline media.

Owing to the extensive applications of hydrogen peroxide (H2O2) in biological, environmental and chemical engineering, it is of great importance to investigate sensitive and selective sensing platform towards the detection of H2O2. Herein, oxygen-implanted MoS2 nanoparticles decorated graphene nanocomposite is synthesized via a facile one-pot solvothermal method for the sensitive detection of H2O2 in alkaline media. The structure and morphology of the MoS2/graphene nanocomposites were systematically characterized, showing that Mo-O bonds are formed and oxygen is implanted into the crystal structure in the nanocomposite. As a result, the MoS2/graphene composite exhibited enhanced electron transfer kinetics and excellent electro-reduction performance towards H2O2 in alkaline media. Under optimum conditions, the fabricated sensor demonstrated a wide linear response towards H2O2 in the range of 0.25-16mM with a low detection limit of 0.12µM and high sensitivity of 269.7µAmM-1cm-2. Besides, the constructed sensor presented a good selectivity to H2O2 with the presence of other interfering species. Therefore, the proposed sensor was successfully applied for the detection and determination of H2O2 in real sample, indicating great potential for the practical applications.

Potential sensing platform of silver nanoparticles embedded in functionalized silicate shell for nitroaromatic compounds.

A simple and new method to grow a pentagonally twinned structure of silver-silicate core-shell nanoparticles in aqueous environment at room temperature and its application in nitrobenzene (NB) sensing is described here. Silver-silicate core-shell nanoparticles were obtained by one-step synthesis using N-[3-(trimethoxysilyl)propyl]-ethylene diamine (EDAS) as a reducing/stabilizing agent and cetyltrimethylammonium bromide (CTAB) as the growing agent for the growth of silver nanoparticles (Ag(nps)). The silver-silicate core-shell nanoparticles were characterized by high-resolution transmission electron microscopy (HRTEM), X-ray diffraction (XRD), scanning electron microscope (SEM), UV-visible absorption, emission, excitation, and electrochemical measurements. The electrochemical studies of silver-silicate core-shell nanoparticles modified electrode showed the silver nanoparticle's oxidation potential and their corresponding reduction potential at 0.24 and -0.16 V, respectively. The optical and electrochemical applications silicate-shell stabilized silver nanoparticles were established toward nitrobenzene. The optical sensing of nitrobenzene by silver-silicate core-shell nanoparticles studied using absorption and emission spectral methods showed experimentally determined lowest detection limits (LOD) of 1 and 10 microM, respectively. Silver-silicate core-shell nanoparticles showed excellent electrocatalytic activity toward the reduction of nitrobenzene. The electrochemical sensor showed the lowest detection limit (LOD) of 2.5 nM toward nitrobenzene sensing.