TiO2/Ag-based photodeposited catalyst boosted electrochemiluminescence of ninhydrin-hydrogen peroxide system for ultrasensitive sensing of copper (II).

Photodeposited TiO2/Ag nanocomposites were generally used to be a friendly catalyst for degrading organic contaminant in environmental field. However, electrochemiluminescence (ECL) sensing analysis based on photocatalysts remains a significant challenge. Herein, polyvinylimide (PEI)-TiO2/Ag nanocomposites (PEI-TiO2/AgNCPs) film with reduced graphene oxide(r-GO) was constructed as a sensing interface for copper(II) ECL detection. TiO2/Ag nanocomposites was prepared by reversed phase microemulsion method and photodeposition technique. Moreover, it was discovered that a small amount of Cu2+ could obviously boost the ECL signal of ninhydrin-hydrogen peroxide system. Signal amplification was achieved by using the synergistic effect between r-GO and TiO2/Ag nanocomposites, and the efficiently concentrated effect of PEI to Cu2+. Furthermore, the investigation showed that ECL mechanism of ninhydrin-hydrogen peroxide system was attributed to the generated hydroxyl radical and superoxide anion during the several type of reactions. Thus for the first time, an ultrasensitive ECL approach for detecting Cu2+ could be performed using ninhydrin as an ECL signal probe and hydrogen peroxide as a co-reaction reagent. Under the suitable circumstances, the proposed method showed an excellent linear relationship in the concentration range of Cu2+ from 1.0 fM to 5.0 nM. Detection limit was estimated to be as low as 0.26 fM. The sensing interface expanded the application of photodeposited TiO2/Ag nanocomposites in ultrasensitive ECL detection. It has potential applications in other components and biological analysis.

Binding of single/double stranded ct-DNA with graphene oxide­silver nanocomposites in vitro: A multispectroscopic approach.

The fundamental binding of single-stranded (ssDNA) and double-stranded DNA (dsDNA) with graphene oxide-Ag nanocomposites (GO-AgNCPs) has been systematically investigated by multi spectroscopic methods, i.e. ultraviolet-visible (UV-vis) absorption, fluorescence spectroscopy, and circular dichroism (CD). The experimental and theoretical results demonstrate that both ssDNA and dsDNA can be adsorbed onto the GO-AgNCPs surface. All of the evidence indicated that there were relatively strong binding of ssDNA/dsDNA with GO-AgNCPs. The article compares the differences in binding between the two types of DNA and the nanomaterials using spectroscopic and thermodynamic data. UV-vis absorption spectroscopy experiments indicate that the characteristic absorbance intensity of both ss DNA and ds DNA increases, but the rate of change in absorbance is different. The fluorescence results revealed that ss/dsDNA could interact with the GO-AgNCPs surface, in spite of the different binding affinities. The Ka value of ssDNA binding with GO-AgNCPs is greater than that of dsDNA at each constant temperature, indicating that the affinity of dsDNA toward GO-AgNCPs is comparatively weak. Molecular docking studies have corroborated the mentioned experimental results. The calculated thermodynamic parameters showed that the binding process was thermodynamically spontaneous, van der Waals force and hydrogen bonding played predominant roles in the binding process. The mechanism of ss/ds DNA binding with GO-AgNCPs was also investigated, and the results indicated that GO-AgNCPs directly binds to the minor groove of ss/ds DNA by replacing minor groove binders.

Cytotoxicity and Antibiofilm Activity of Silver-Polypropylene Nanocomposites.

The development of biocompatible nanomaterials that interface with human skin and tissue is critical for advancing prosthetics and other therapeutic medical needs. In this perspective, the development of nanoparticles with cytotoxicity and antibiofilm properties and biocompatibility characteristics are important. Metallic silver (Ag) exhibits good biocompatibility, but it is often challenging to integrate it into a nanocomposite without compromising its antibiofilm properties for optimal applications. In this study, new polymer nanocomposites (PNCs) with ultra-low filling content (0.0023-0.046 wt%) of Ag nanoplates were manufactured and tested. The cytotoxicity and antibiofilm activity of different composites with polypropylene (PP) matrix were examined. At first, PNCs surface were analyzed by means of AFM (atomic force microscopy) with phase contrast evaluation and FTIR (Fourier-transform infrared spectroscopy) to study the Ag nanoplates distribution. Subsequently, the cytotoxicity and growth properties of biofilms were assessed by MTT assay protocol and detection of nitric oxide radicals. Antibacterial and antibiofilm activities were measured against Gram-positive bacteria (Staphylococcus aureus) and Gram-negative bacteria (K. pneumoniae). The PNCs with silver exhibited antibiofilm activity although they did not inhibit regular planktonic bacterial growth. Moreover, the PNCs were not cytotoxic to mammalian cells and did not induce significant immune response. These features reveal the potential of the PNCs developed in this study for usage in fabrication of prosthetics and other smart structures for biomedical applications.

Multifunctional magnetic Fe3O4/Cu2O-Ag nanocomposites with high sensitivity for SERS detection and efficient visible light-driven photocatalytic degradation of polycyclic aromatic hydrocarbons (PAHs).

Polycyclic aromatic hydrocarbons (PAHs) with carcinogenic, teratogenic and mutagenic properties are persistent organic pollutants in the environment. Herein, the novel multifunctional Fe3O4/Cu2O-Ag nanocomposites (NCs) have been established for ultra-sensitive surface-enhanced Raman scattering (SERS) detection and visible light-driven photocatalytic degradation of PAHs. Fe3O4/Cu2O-Ag NCs with different amounts of Ag nanocrystals were synthesized, and the effect of Ag contents on SERS performance was studied by finite-difference time-domain (FDTD) algorithm. The synergistic interplay of electromagnetic and chemical enhancement was responsible for excellent SERS sensitivity of Fe3O4/Cu2O-Ag NCs. The limit of detection (LOD) of optimal SERS substrates (FCA-2 NCs) for Nap, BaP, Pyr and Ant was as low as 10-9, 10-9, 10-9 and 10-10 M, respectively. The SERS detection of PAHs in actual soil environment was also studied. Moreover, a simple SERS method was used to monitor the photocatalytic process of PAHs. The recovery and reuse of Fe3O4/Cu2O-Ag NCs were achieved through magnetic field, and the outstanding SERS and photocatalytic performance were still maintained even after eight cycles. This magnetic multifunctional NCs provide a unique idea for the integration of ultra-sensitive SERS detection and efficient photocatalytic degradation of PAHs, and thus will have more hopeful prospects in the field of environmental protection.

Multifunctional SERS chip mediated by black phosphorus@gold-silver nanocomposites inserted in bilayer membrane for in-situ detection and degradation of hazardous materials.

Self-cleaning surface-enhanced Raman scattering (SERS) substrates dependent on versatile two-dimensional semiconductors offer an efficient channel for the sensitive monitoring and timely degradation of hazardous molecules. Herein, a kind of sophisticated SERS-active nanocomposites was developed by incorporating Au-Ag nanoparticles onto black phosphorus (BP) nanosheets via photo-induced self-reduction. Combining the substantial electromagnetic "hot spots" triggered by bimetallic plasma coupling effect and the efficient charge transfer from BP to probe molecules, the proposed nanocomposites featured attractive SERS enhancement, facilitating a limit of detection down to 4.5 × 10-10 M. Attributed to the remarkable restriction of electron-hole recombination stemming from "Schottky contact", the photocatalytic activity of BP was prominently boosted, demonstrating a complete degradation time as short as 65 min. Furthermore, the disgusting instability of BP was considerably hindered by inserting the nanocomposites into various bilayer matrices with diverse hardness and viscosity inspired by cling film principle. Moreover, a significantly elevated collection rate high to 93.1% for in-situ detection was also achieved by the as-manufactured flexible SERS chips based on tape. This study illustrates a clear perspective for the development of versatile BP-based SERS chips which might facilitate sensitive analysis and treatment of perilous contaminants in complicated real-life scenarios.

Synthesis of chitosan/silver nanocomposites by phase inversion with the assistance of carbon dioxide.

Carbon dioxide (CO2) assisted synthesis of water-soluble silver nanoparticle with a narrow particle size distribution is reported here based on the phase-inversion procedure. Bio-derived chitosan (CS) is used to stabilize the metal nanoparticles according to its abundant functional groups. Formic acid is employed as both a solvent (for the polymer) and a reductant for in-situ reducing the silver precursor along with the solvent evaporation. CO2 is utilized to combine with the amino groups of CS, reducing the viscosity of chitosan/formic acid solution and limiting the formation of hydrogen bonds. This promotes the stabilization and reduction efficiency of silver nanoparticles. In particular, 100% of Ag metal nanoparticles with the size of 7.5 ± 2.3 nm is successfully synthesized with the assistance of CO2. Interestingly, the synthesized CS/Ag nanocomposites are water-soluble owing to the formation of carbamate groups. This water-soluble silver nanoparticle presents an exceptional performance in the selective reduction of 4-nitrophenol, where the turnover frequency (TOF = 599 h-1) is even double with respect to the CO2 free system.

Structure and Properties of Polyoxymethylene/Silver/Maleic Anhydride-Grafted Polyolefin Elastomer Ternary Nanocomposites.

In the present study, silver (Ag) nanoparticles and maleic anhydride-grafted polyolefin elastomer (MAH-g-POE) were used as enhancement additives to improve the performance of the polyoxymethylene (POM) homopolymer. Specifically, the POM/Ag/MAH-g-POE ternary nanocomposites with varying Ag nanoparticles and MAH-g-POE contents were prepared by a melt mixing method. The effects of the additives on the microstructure, thermal stability, crystallization behavior, mechanical properties, and dynamic mechanical thermal properties of the ternary nanocomposites were studied. It was found that the MAH-g-POE played a role in the bridging of the Ag nanoparticles and POM matrix and improved the interfacial adhesion between the Ag nanoparticles and POM matrix, owing to the good compatibility between Ag/MAH-g-POE and the POM matrix. Moreover, it was found that the combined addition of Ag nanoparticles and MAH-g-POE significantly enhanced the thermal stability, crystallization properties, and mechanical properties of the POM/Ag/MAH-g-POE ternary nanocomposites. When the Ag/MAH-g-POE content was 1 wt.%, the tensile strength reached the maximum value of 54.78 MPa. In addition, when the Ag/MAH-g-POE content increased to 15wt.%, the elongation at break reached the maximum value of 64.02%. However, when the Ag/MAH-g-POE content further increased to 20 wt.%, the elongation at break decreased again, which could be attributed to the aggregation of excessive Ag nanoparticles forming local defects in the POM/Ag/MAH-g-POE ternary nanocomposites. Furthermore, when the Ag/MAH-g-POE content was 20 wt.%, the maximum decomposition temperature of POM/Ag/MAH-g-POE ternary nanocomposites was 398.22 °C, which was 71.39 °C higher than that of pure POM. However, compared with POM, the storage modulus of POM/Ag/MAH-g-POE ternary nanocomposites decreased with the Ag/MAH-g-POE content, because the MAH-g-POE elastomer could reduce the rigidity of POM.

PB@PDA@Ag nanosystem for synergistically eradicating MRSA and accelerating diabetic wound healing assisted with laser irradiation.

The ever-growing threats of multidrug-resistant bacterial infection and chronic wound healing have created an imperative need for the development of novel antibacterial materials and therapeutic strategies, especially for diabetic patients infected with multidrug-resistant bacteria. In this work, the nanocomplexes named as PB@PDA@Ag were used for eradicating multidrug-resistant bacteria and accelerating wound healing of MRSA-infected diabetic model with the assistance of laser irradiation. In vitro results revealed that the combinational strategy exerted a synergistic effect for anti-MRSA through disrupting cell integrity, producing ROS, declining ATP, and oxidizing GSH, comparing with PB@PDA@Ag or NIR laser irradiation alone. Moreover, in vivo assay demonstrated that this system effectively accelerated MRSA-infected diabetic wound healing by mitigating local inflammatory response and up-regulating VEGF expression on the wound bed. Meanwhile, satisfactory biocompatibility and negligible damage to major organs were observed. Altogether, the aforementioned results indicate that the combinational therapy of PB@PDA@Ag and NIR irradiation shows a great potential application in the field of clinic infection.

Effect of Silver Nanoparticles on the Microstructure, Non-Isothermal Crystallization Behavior and Antibacterial Activity of Polyoxymethylene.

Silver (Ag) nanoparticles were synthesized by a facile route in the presence of oleic acid and n-propylamine. It was shown that the average primary size of the as-synthesized Ag nanoparticles was approximately 10 nm and the surface of as-synthesized Ag nanoparticles was capped with monolayer surfactants with the content of 19.6%. Based on as-synthesized Ag nanoparticles, polyoxymethylene (POM)/Ag nanocomposites were prepared. The influence of Ag nanoparticles on non-isothermal crystallization behavior of POM was investigated by differential scanning calorimetry (DSC). The Jeziorny, Jeziorny-modified Avrami, Ozawa, Liu and Mo, Ziabicki and Kissinger models were applied to analyze the non-isothermal melt crystallization data of POM/Ag nanocomposites. Results of half time (t1/2), crystallization rate parameter (CRP), crystallization rate function (K(T)), kinetic parameter (F(T)), the kinetic crystallizability at unit cooling rate (GZ) and the crystallization activation energy (∆E) were determined. Small amounts of Ag nanoparticles dispersed into POM matrix were shown to act as heterogeneous nuclei, which could enhance the crystallization rate of POM, increase the number of POM spherulites and reduce POM spherulites size. However, the higher loading of Ag nanoparticles were easily aggregated, which restrained POM crystallization to some degree. Furthermore, the POM/Ag nanocomposites showed robust antibacterial activity against Escherichia coli and Staphylococcus aureus.

A green and facile synthesis for rGO/Ag nanocomposites using one-step chemical co-reduction route at ambient temperature and combined first principles theoretical analyze.

Recently, graphene decorated with various inorganic nanoparticles, such as Pt, Au, Ag, TiO2 and Fe3O4, among which Ag nanocomposites are good candidates for electronics, optics, electrochemistry and catalysis. However, preparation techniques for Ag nanoparticles/carbon matrix hybrids require tedious multi-step processes often involving toxic reducing agents/high temperatures which is not viable for scalable production. Here, a facile, one step and eco-friendly chemical co-reduction route was utilized to synthesis of a new nanocomposites by Ag nanoparticle anchored on reduced graphene oxide (rGO) at ambient temperature and combined first principles theoretical analyze their interfacial adsorption behavior, is reported. In this way, graphene oxide (GO) and Ag+ simultaneously reduced by thiourea dioxide (TD) without using any additional reduced reactants. Results indicated that GO was successfully reduced to rGO and well-dispersed Ag nanoparticles with sizes of 6-7 nm, anchored on the surface of rGO sheets. Reduction mechanism was attributed to the synergistic effect of its hydrolysis products in aqueous media. The experiment and theoretical calculation results obtained demonstrate this method to be applicable to the synthesis of other metals on rGO sheets in order to improve wettability and interfacial bonding between rGO and metal and may possibly find various forthcoming medicinal, industrial and technological applications.

A Novel Au@Cu2O-Ag Ternary Nanocomposite with Highly Efficient Catalytic Performance: Towards Rapid Reduction of Methyl Orange Under Dark Condition.

Au@Cu2O core-shell nanocomposites (NCs) were synthesized by reducing copper nitrate on Au colloids with hydrazine. The thickness of the Cu2O shells could be varied by adjusting the molar ratios of Au: Cu. The results showed that the thickness of Cu2O shells played a crucial role in the catalytic activity of Au@Cu2O NCs under dark condition. The Au@Cu2O-Ag ternary NCs were further prepared by a simple galvanic replacement reaction method. Moreover, the surface features were revealed by TEM, XRD, XPS, and UV-Vis techniques. Compared with Au@Cu2O NCs, the ternary Au@Cu2O-Ag NCs had an excellent catalytic performance. The degradation of methyl orange (MO) catalyzed by Au@Cu2O-Ag NCs was achieved within 4 min. The mechanism study proved that the synergistic effects of Au@Cu2O-Ag NCs and sodium borohydride facilitated the degradation of MO. Hence, the designed Au@Cu2O-Ag NCs with high catalytic efficiency and good stability are expected to be the ideal environmental nanocatalysts for the degradation of dye pollutants in wastewater.

Highly Efficient, Low-Cost, and Magnetically Recoverable FePt⁻Ag Nanocatalysts: Towards Green Reduction of Organic Dyes.

Nowadays, synthetic organic dyes and pigments discharged from numerous industries are causing unprecedentedly severe water environmental pollution, and conventional water treatment processes are hindered due to the corresponding sophisticated aromatic structures, hydrophilic nature, and high stability against light, temperature, etc. Herein, we report an efficient fabrication strategy to develop a new type of highly efficient, low-cost, and magnetically recoverable nanocatalyst, i.e., FePt⁻Ag nanocomposites, for the reduction of methyl orange (MO) and rhodamine B (RhB), by a facile seed deposition process. X-ray diffraction results elaborate that the as-synthesized FePt⁻Ag nanocomposites are pure disordered face-centered cubic phase. Transmission electron microscopy studies demonstrate that the amount of Ag seeds deposited onto the surfaces of FePt nanocrystals increases when increasing the additive amount of silver colloids. The linear correlation of the MO and RhB concentration versus reaction time catalyzed by FePt⁻Ag nanocatalysts is in line with pseudo-first-order kinetics. The reduction rate constants of MO and RhB increase with the increase of the amount of Ag seeds. FePt⁻Ag nanocomposites show good separation ability and reusability, and could be repeatedly applied for nearly complete reduction of MO and RhB for at least six successive cycles. Such cost-effective and recyclable nanocatalysts provide a new material family for use in environmental protection applications.

Study on the interaction of graphene oxide­silver nanocomposites with bovine serum albumin and the formation of nanoparticle-protein corona.

The interaction between graphene oxide-sliver nanocomposites (GO-AgNCPs) and bovine serum albumin (BSA) in aqueous buffer solution was investigated by using several spectroscopic and imaging techniques. The visible absorbance intensity of GO-AgNCPs increased with increasing concentrations of BSA, and a slight redshift of the surface plasmon resonance band (SPR) occurred due to the absorption of BSA on the surface of GO-AgNCPs. Fluorescence data revealed a static quenching process of BSA caused by GO-AgNCPs. Thermodynamic parameters of the absorption process, including adsorption equilibrium constants, changes in Gibbs free energy (ΔG), enthalpy (ΔH) and entropy (ΔS), were evaluated at different temperatures. Negative values of ΔG showed that this process was spontaneous and the BSA-GO-AgNCPs complex might form in aqueous solution. Negative values of ΔH and ΔS suggested that the binding was mainly an enthalpy-driven process, and van der Waals forces and hydrogen bonding were the major force in the formation of the nanoparticle-protein corona. Analysis of synchronous, three dimensional (3D) fluorescence and circular dichroism (CD) spectra demonstrated that the conformation of BSA was slightly altered in the presence of GO-AgNCPs. The protein corona formed on the surface of GO-AgNCPs was directly observed by scanning probe microscopy (SPM).

Visible light driven photo-degradation of Congo red by TiO2ZnO/Ag: DFT approach on synergetic effect on band gap energy.

In this paper, we report the combination of two metal oxides (TiO2ZnO) that allows mixed density of states to reduce band gap energy, facilitating the photo-oxidation of Congo red dye under visible light. For the oxidation, a possible mechanism is proposed after analyzing the intermediates by GC-MS, and it is consistent with Density Functional Theory (DFT). The nanohybrids were characterized comprehensibly by several analytical techniques such as X-Ray diffraction (XRD), Transmission Electron Microscopy (TEM), Atomic Force Microscopy (AFM), and X-ray Photoelectron Spectroscopy (XPS). For the addition of ZnO to TiO2, a dominance of anatase phase was found rather than other phases (rutile or brookite). A broad band (∼550 nm) is observed in UV-Visible spectra for TiO2ZnO/Ag NPs nm because of Surface Plasmon properties of Ag NPs. The band gap energy was calculated for TiO2ZnO/Ag system, and then it has been further studied by DFT in order to show why the convergence of two semiconductors allows a mixed density of states, facilitating the reduction of the energy gap between occupied and unoccupied bands; ultimately, it improves the performance of catalysts under visible light. Significantly, the interaction of crystal planes (0 0 I) of TiO2 anatase and (0 0 1) of ZnO crucially plays as an important role for the reduction of energy band-gap. Additionally, TiO2ZnOAg NPs were used recognize Saccharomyces cerevisiae cells by con-focal fluorescence microscope, showing that it develops bright bio-images for the cells; while for TiO2 or ZnO or TiO2ZnO NPs, no fluorescent response was seen within the cells.

Melanin-Associated Synthesis of SERS-Active Nanostructures and the Application for Monitoring of Intracellular Melanogenesis.

Melanin plays an indispensable role in the human body. It serves as a biological reducer for the green synthesis of precious metal nanoparticles. Melanin-Ag nanocomposites were successfully produced which exhibited very strong surface-enhanced Raman scattering (SERS) effect because of the reducibility property of melanin. A melanin-Ag composite structure was synthesized in situ in melanin cells, and SERS technique was performed for the rapid imaging and quantitative assay of intracellular melanin. This imaging technique was also used to successfully trace the formation and secretion of intracellular melanin after stimulation with melanin-stimulating hormones. Based on the self-reducing property of melanin, the proposed SERS imaging method can provide potentially powerful analytical detection tools to study the biological functions of melanin and to prevent and cure melanin-related diseases.

Antimicrobial Properties and Cytocompatibility of PLGA/Ag Nanocomposites.

The purpose of this study was to investigate the antimicrobial properties of multifunctional nanocomposites based on poly(dl-Lactide-co-Glycolide) (PLGA) and increasing concentration of silver (Ag) nanoparticles and their effects on cell viability for biomedical applications. PLGA nanocomposite films, produced by solvent casting with 1 wt%, 3 wt% and 7 wt% of Ag nanoparticles were investigated and surface properties were characterized by atomic force microscopy and contact angle measurements. Antibacterial tests were performed using an Escherichia coli RB and Staphylococcus aureus 8325-4 strains. The cell viability and morphology were performed with a murine fibroblast cell line (L929) and a human osteosarcoma cell line (SAOS-2) by cell viability assay and electron microscopy observations. Matrix protein secretion and deposition were also quantified by enzyme-linked immunosorbent assay (ELISA). The results suggest that the PLGA film morphology can be modified introducing a small percentage of silver nanoparticles, which induce the onset of porous round-like microstructures and also affect the wettability. The PLGA/Ag films having silver nanoparticles of more than 3 wt% showed antibacterial effects against E. coli and S. aureus. Furthermore, silver-containing PLGA films displayed also a good cytocompatibility when assayed with L929 and SAOS-2 cells; indicating the PLGA/3Ag nanocomposite film as a promising candidate for tissue engineering applications.

Novel ZnO:Ag nanocomposites induce significant oxidative stress in human fibroblast malignant melanoma (Ht144) cells.

The use of photoactive nanoparticles (NPs) such as zinc oxide (ZnO) and its nanocomposites has become a promising anticancer strategy. However, ZnO has a low photocatalytic decomposition rate and the incorporation of metal ions such as silver (Ag) improves their activity. Here different formulations of ZnO:Ag (1, 3, 5, 10, 20 and 30% Ag) were synthesized by a simple co-precipitation method and characterized by powder X-ray diffraction, scanning electron microscopy, Rutherford back scattering and diffuse reflectance spectroscopy for their structure, morphology, composition and optical band gap. The NPs were investigated with regard to their different photocatalytic cytotoxic effects in human malignant melanoma (HT144) and normal (HCEC) cells. The ZnO:Ag nanocomposites killed cancer cells more efficiently than normal cells under daylight exposure. Nanocomposites having higher Ag content (10, 20 and 30%) were more toxic compared to low Ag content (1, 3 and 5%). For HT144, under daylight exposure, the IC50 values were ZnO:Ag (10%): 23.37 µg/mL, ZnO:Ag (20%): 19.95 µg/mL, and ZnO:Ag (30%): 15.78 µg/mL. ZnO:Ag (30%) was toxic to HT144 (IC50: 23.34 µg/mL) in dark as well. The three nanocomposites were further analyzed with regard to their ability to generate reactive oxygen species (ROS) and induce lipid peroxidation. The particles led to an increase in levels of ROS at cytotoxic concentrations, but only HT144 showed strongly induced MDA level. Finally, NPs were investigated for the ROS species they generated in vitro. A highly significant increase of (1)O2 in the samples exposed to daylight was observed. Hydroxyl radical species, HO(•), were also generated to a lesser extent. Thus, the incorporation of Ag into ZnO NPs significantly improves their photo-oxidation capabilities. ZnO:Ag nanocomposites could provide a new therapeutic option to selectively target cancer cells.

Facile and label-free detection of lung cancer biomarker in urine by magnetically assisted surface-enhanced Raman scattering.

Adenosine plays a crucial role in the regulation of physiological activity in various tissues and organs. As adenosine is a possible biomarker for cancer, the determination of its level presents a demanding task for deeply monitoring progress of diseases. Through the synthesis of Fe3O4/Au/Ag nanocomposites weaved and stabilized by phytic acid and its salt, we develop a magnetically assisted surface-enhanced Raman scattering (SERS) protocol to determine trace level adenosine in urine samples from both lung cancer patients and health human. The magnetic properties of the nanocomposites enable to realize the simple separation of targeted molecules from a complex matrix and the Au/Ag nanoparticles moieties act as the SERS platform. This label-free Fe3O4/Au/Ag-nanocomposites-based SERS protocol shows a good stability, reproducibility, time efficiency (less than 20 min for one sample test), and huge sensitivity down to 1 × 10(-10) M. The protocol also has high selectivity because SERS signal of adenosine provides the molecular fingerprint information as well as an azo coupling pretreatment is performed to remove the interference of urea. Furthermore, a SERS array is designed for on-site screening adenosine in urine samples in a massive way using a portable Raman. Such a magnetically assisted SERS method as a powerful alternative can be expected as a smart and promising tool for effective assessment of healthcare.