Room-Temperature Self-Healing Conductive Elastomers for Modular Assembly as a Microfluidic Electrochemical Biosensing Platform for the Detection of Colorectal Cancer Exosomes.

Modular components for rapid assembly of microfluidics must put extra effort into solving leakage and alignment problems between individual modules. Here, we demonstrate a conductive elastomer with self-healing properties and propose a modular microfluidic component configuration system that utilizes self-healing without needing external interfaces as an alternative to the traditional chip form. Specifically, dual dynamic covalent bond crosslinks (imine and borate ester bonds) established between Polyurethane (PU) and 2-Formylbenzeneboronic acid (2-FPBA) are the key to a hard room-temperature self-healing elastomeric substrate PP (PU/2-FPBA). An MG (MXene/GO) conductive network with stable layer spacing (Al-O bonds) obtained from MXene and graphene oxide (GO) by in situ reduction of metals confers photothermal conductivity to PP. One-step liquid molding obtained a standardized modular component library of puzzle shapes from PP and MGPP (MG/PP). The exosomes were used to validate the performance of the constructed microfluidic electrochemical biosensing platform. The device has a wide detection range (50-105 particles/µL) and a low limit of detection (LOD) (42 particles/µL) (S/N = 3), providing a disposable, reusable, cost-effective, and rapid analysis platform for quantitative detection of colorectal cancer exosomes. In addition, to our knowledge, this is the first exploration of self-healing conductive elastomers for a modular microfluidic electrochemical biosensing platform.

Electrochemical Micro-Immunosensor of Cubic AuPt Dendritic Nanocrystals/Ti3C2-MXenes for Exosomes Detection.

Exosomes are extracellular vesicles that exist in body circulation as intercellular message transmitters. Although the potential of tumor-derived exosomes for non-invasive cancer diagnosis is promising, the rapid detection and effective capture of exosomes remains challenging. Herein, a portable electrochemical aptasensor of cubic AuPt dendritic nanocrystals (AuPt DNs)/Ti3C2 assisted in signal amplification, and aptamer CD63 modified graphene oxide (GO) was immobilized on a screen-printed carbon electrode (SPCE) as the substrate materials for the direct capture and detection of colorectal carcinoma exosomes. Cubic AuPt DNs/Ti3C2 was synthesized according to a simple hydrothermal procedure, and the AuPt DNs/Ti3C2-Apt hybrid demonstrated an efficient recognition of exosomes. Under optimal conditions, a detection limit of down to 20 exosomes µL-1 was achieved with the linear range from 100 exosomes µL-1 to 5.0 × 105 exosomes µL-1. The proposed immunosensor could be suitable for the analysis of exosomes and has clinical value in the early diagnosis of cancer.

New Ultrasensitive Sandwich-Type Immunoassay of Dendritic Tri-Fan Blade-like PdAuCu Nanoparticles/Amine-Functionalized Graphene Oxide for Label-Free Detection of Carcinoembryonic Antigen.

The early detection of tumor markers has an effective role in the treatment of cancer. Here, a new sandwich-type electrochemical immunosensor for early label-free detection of the cancer biomarker carcinoembryonic antigen (CEA) was developed. Dendritic tri-fan blade-like PdAuCu nanoparticles (PdAuCu NPs)/amine functionalized graphene oxide (NH2-GO) were the label of secondary antibodies (Ab2), and Au nanoparticle-decorated polydopamines (Au/PDA) were immobilized on a screen-printed carbon electrode (SPCE) as the substrate materials. Dendritic tri-fan blade-like PdAuCu NPs/NH2-GO was synthesized according to a simple hydrothermal procedure and used to immobilize antibodies (Ab2) with large surfaces areas, increased catalytic properties and good adsorption to amplify the current signals. Subsequently, Ab2/PdAuCu NPs/NH2-GO catalyzed the reduction of H2O2 in the sandwich-type immunoreactions. Under optimal conditions, the immunosensor exhibited a satisfactory response to CEA with a limit detection of 0.07 pg mL-1 and a linear detection range from 0.1 pg mL-1 to 200 ng mL-1. The proposed immunosensor could be suitable enough for a real sample analysis of CEA, and has clinical value in the early diagnosis of cancer.

Recent progress in the development of upconversion nanomaterials in bioimaging and disease treatment.

Multifunctional lanthanide-based upconversion nanoparticles (UCNPs), which feature efficiently convert low-energy photons into high-energy photons, have attracted considerable attention in the domain of materials science and biomedical applications. Due to their unique photophysical properties, including light-emitting stability, excellent upconversion luminescence efficiency, low autofluorescence, and high detection sensitivity, and high penetration depth in samples, UCNPs have been widely applied in biomedical applications, such as biosensing, imaging and theranostics. In this review, we briefly introduced the major components of UCNPs and the luminescence mechanism. Then, we compared several common design synthesis strategies and presented their advantages and disadvantages. Several examples of the functionalization of UCNPs were given. Next, we detailed their biological applications in bioimaging and disease treatment, particularly drug delivery and photodynamic therapy, including antibacterial photodynamic therapy. Finally, the future practical applications in materials science and biomedical fields, as well as the remaining challenges to UCNPs application, were described. This review provides useful practical information and insights for the research on and application of UCNPs in the field of cancer.

Specific Anti-biofilm Activity of Carbon Quantum Dots by Destroying P. gingivalis Biofilm Related Genes.

INTRODUCTION: Biofilms protect bacteria from antibiotics and this can produce drug-resistant strains, especially the main pathogen of periodontitis, Porphyromonas gingivalis. Carbon quantum dots with various biomedical properties are considered to have great application potential in antibacterial and anti-biofilm treatment. METHODS: Tinidazole carbon quantum dots (TCDs) and metronidazole carbon quantum dots (MCDs) were prepared by a hydrothermal method with the clinical antibacterial drugs tinidazole and metronidazole, respectively. Then, TCDs and MCDs were characterized by transmission electron microscopy, UV-visible spectroscopy, infrared spectroscopy and energy-dispersive spectrometry. The antibacterial effects were also investigated under different conditions. RESULTS: The TCDs and MCDs had uniform sizes. The results of UV-visible and energy-dispersive spectrometry confirmed their important carbon polymerization structures and the activity of the nitro group, which had an evident inhibitory effect on P. gingivalis, but almost no effect on other bacteria, including Escherichia coli, Staphylococcus aureus and Prevotella nigrescens. Importantly, the TCDs could penetrate the biofilms to further effectively inhibit the growth of P. gingivalis under the biofilms. Furthermore, it was found that the antibacterial effect of TCDs lies in its ability to impair toxicity by inhibiting the major virulence factors and related genes involved in the biofilm formation of P. gingivalis, thus affecting the self-assembly of biofilm-related proteins. CONCLUSION: The findings demonstrate a promising new method for improving the efficiency of periodontitis treatment by penetrating the P. gingivalis biofilm with preparations of nano-level antibacterial drugs.

An Electrochemical Immunosensor for Sensitive Detection of the Tumor Marker Carcinoembryonic Antigen (CEA) Based on Three-Dimensional Porous Nanoplatinum/Graphene.

Carcinoembryonic antigen (CEA) is an important broad-spectrum tumor marker. The quantitative detection of a low concentration of CEA has important medical significance. In this study, three-dimensional porous graphene-oxide-supported platinum metal nanoparticles (3DPt/HGO) composites were prepared by a wet chemical method and modified on an electrode with enhanced conductivity, a large surface area, and good adsorption of immobilizing antibodies (Ab1). Horseradish peroxidase (HRP)-functionalized Au nanoparticles were fabricated to label the secondary antibodies (Ab2). The proposed immunosensor showed a good linear relationship in the range of 0.001-150 ng/mL for CEA and a detection limit of 0.0006 ng/mL. The immunosensor had high sensitivity, good stability and reproducibility, and has great application prospects for the clinical diagnosis of cancer.

Preparation and Evaluation of Upconversion Nanoparticles Based miRNA Delivery Carrier in Colon Cancer Mice Model.

Therapeutic efficacy of solid tumor is often severely hampered by poor penetration of therapeutics into diseased tissues and lack of tumor targeting. In this study, the functionalized upconversion nanoparticles (UCNP)-based delivery vector targeting cancer cells was developed. Firstly, NaYF4:Yb/Tm (UCNP) was prepared with the solvothermal method for the uniform nanoparticle size and brilliant lattice structure. The SiO2 coated UCNP was demonstrated a high upconversion emission and good monodispersity, which was coupled with polyetherimide (PEI) and miR-145 vector. Then, it was further functionalized via hyaluronic acid (HA) (UCNP/PEI/HA Nanocomplex, UCNPs) coating for the targeted delivery and improved biocompatibility. The UCNPs/miR-145 displays an excellent biocompatibility, a high level of cellular uptake and miR-145 expression, which results in a significant cell cycle arrest in G1, and induces CCND1, CDK6 and CCNE2 proteins downregulation. In vivo, the HA-coated UCNPs were enriched at the tumor site by targeting and retention effects, which resulted in a significant inhibition of tumor growth. Histological experiments demonstrated that UCNPs did not show significant toxicity in mice colon cancer model. Taken together, a UCNPs-based delivery platform was successfully constructed and used for miRNA target delivery, which provided a new method and idea for bioengineering and nanotechnology-based tumor therapy.

Three-Dimensional Holey-Graphene Architectures for Highly Sensitive Enzymatic Electrochemical Determination of Hydrogen Peroxide.

Three-dimensional (3D) graphene with high specific surface area, excellent conductivity and designed porosity is essential for many practical applications. Herein, holey graphene oxide with nano pores was facilely prepared via a convenient mild defect-etching reaction and then fabricated to 3D nanostructures via a reduction method. Based on the 3D architectures, a novel enzymatic hydrogen peroxide sensor was successfully fabricated. Transmission electron microscopy (TEM), scanning electron microscopy (SEM), fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) were used to characterize the 3D holey graphene oxide architectures (3DHGO). Cyclic voltammetry (CV) was used to evaluate the electrochemical performance of 3DHGO at glassy carbon electrode (GCE). Excellent electrocatalytic activity to the reduction of H2O2 was observed, and a linear range of 5.0×10-8~5.0×10-5 M with a detection limit of 3.8×10-9 M was obtained. These results indicated that 3DHGO have potential as electrochemical biosensors.

Three-Dimensional Au/Holey-Graphene as Efficient Electrochemical Interface for Simultaneous Determination of Ascorbic Acid, Dopamine and Uric Acid.

The quantification of ascorbic acid (AA), dopamine (DA), and uric acid (UA) has been an important area of research, as these molecules' determination directly corresponds to the diagnosis and control of diseases of nerve and brain physiology. In our research, graphene oxide (GO) with nano pores deposited with gold nanoparticles were self-assembled to form three-dimensional (3D) Au/holey-graphene oxide (Au/HGO) composite structures. The as-prepared 3DAu/HGO composite structures were characterized for their structures by X-ray diffraction, Raman spectrum, scanning electron microscopy, and transmission electron microscopy coupled with cyclic voltammograms. Finally, the proposed 3DAu/HGO displayed high sensitivity, excellent electron transport properties, and selectivity for the simultaneous electrochemical determination of AA, DA and UA with linear response ranges of 1.0⁻500 µM, 0.01⁻50 µM and 0.05⁻50 µM respectively. This finding paves the way for graphene applications as a biosensor for detecting three analytes in human serum.

Hyaluronate-Functionalized Graphene for Label-Free Electrochemical Cytosensing.

Electrochemical sensors for early tumor cell detection are currently an important area of research, as this special region directly improves the efficiency of cancer treatment. Functional graphene is a promising alternative for selective recognition and capture of target cancer cells. In our work, an effective cytosensor of hyaluronate-functionalized graphene (HG) was prepared through chemical reduction of graphene oxide. The as-prepared HG nanostructures were characterized with Fourier transform infrared spectroscopy and transmission electron microscopy coupled with cyclic voltammograms and electrochemical impedance spectroscopy, respectively. The self-assembly of HG with ethylene diamine, followed by sodium hyaluronate, enabled the fabrication of a label-free electrochemical impedance spectroscopy cytosensor with high stability and biocompatibility. Finally, the proposed cytosensor exhibited satisfying electrochemical behavior and cell-capture capacity for human colorectal cancer cells HCT-116, and also displayed a wide linear range, from 5.0 × 10² cells∙mL-1 to 5.0 × 106 cells∙mL-1, and a low detection limit of 100 cells∙mL-1 (S/N = 3) for quantification. This work paves the way for graphene applications in electrochemical cytosensing and other bioassays.

Synergistic effects of polymer adsorbents on the performance of bilirubin hemoperfusion.

Neonatal hyperbilirubinemia (jaundice) is a common disease with high incidence. Currently, the clinical inefficiency of adult bilirubin hemoperfusion medical adsorbent is a major technical barrier for the application of hemoperfusion treatment to rescue the severe neonatal jaundice. Based on the well-known principle of synergistic effects, a series of customized bilirubin polymeric compounds, comprised of one or more of the following components (glycidyl methacrylate, sodium acrylate, methacrylic acid isooctyl, hexamethylene diamine, albumin), were designed and fabricated based on molecular design. Their adsorption performances upon bilirubin were investigated and compared under the same conditions, and the compound with the highest adsorption performance was then subject to preliliminary safety assessments and compared with a commercial one (BS330). The results showed that positive synergistic effects appeared on the adsorption performance to adsorb bilirubin based on this study, and the one comprised of glycidyl methacrylate+sodium acrylate+methacrylic acid isoocty+hexamethylene diamine+albumin possesses the highest adsorption performance as well as outome clinical acceptable medical safety assessments, and its adsorption efficiency was up to 46% while the commerical one's was about 26% under the same conditions. This study sheds a new light on how to design and develop hemoperfusion bilirubin adsorbents with good overall clinical performance, as well as providing a novel idea and experimental referrences for future related topics.

Polyethyleneimine-coated quantum dots for miRNA delivery and its enhanced suppression in HepG2 cells.

Quantum dots (QDs) have been intensively investigated for bioimaging, drug delivery, and labeling probes because of their unique optical properties. In this study, CdSe/ZnS QDs-based nonviral vectors with the dual functions of delivering miR-26a plasmid and bioimaging were formulated by capping the surface of CdSe/ZnS QDs with polyethyleneimine (PEI). The PEI-coated QDs were capable of condensing miR-26a expression vector into nanocomplexes that can emit strong red luminescence when loaded with CdSe/ZnS QDs. Further results showed that PEI-modified nanoparticles (NPs) could transfect miR-26a plasmid into HepG2 cells in vitro. Meanwhile, imaging of living cells could be achieved based on the CdSe/ZnS QDs. Further study suggested that miR-26a transfection up-regulated miR-26a expression, induced cycle arrest, and triggered proliferation inhibition in HepG2 cells. The results indicated that PEI-coated QD NPs possess the capability of bioimaging and gene delivery and could be a promising vehicle with the engineering of QD NPs for gene therapy in the future.

Tabersonine inhibits amyloid fibril formation and cytotoxicity of Aß(1-42).

The misfolding and aggregation of amyloid beta (Aß) peptides into amyloid fibrils are key events in the amyloid cascade hypothesis for the etiology of Alzheimer's disease (AD). Using thioflavin-T (ThT) fluorescence assay, atomic force microscopy, circular dichroism, size exclusion chromatography, surface plasmon resonance (SPR), and cytotoxicity tests, we demonstrate that tabersonine, an ingredient extracted from the bean of Voacanga africana, disrupts Aß(1-42) aggregation and ameliorates Aß aggregate-induced cytotoxicity. A small amount of tabersonine (e.g., 10 µM) can effectively inhibit the formation of Aß(1-42) (e.g., 80 µM) fibrils or convert mature fibrils into largely innocuous amorphous aggregates. SPR results indicate that tabersonine binds to Aß(1-42) oligomers in a dose-dependent way. Molecular dynamics (MD) simulations further confirm that tabersonine can bind to oligomers such as the pentamer of Aß(1-42). Tabersonine preferentially interact with the ß-sheet grooves of Aß(1-42) containing aromatic and hydrophobic residues. The various binding sites and modes explain the diverse inhibitory effects of tabersonine on Aß aggregation. Given that tabersonine is a natural product and a precursor for vincristine used in cancer chemotherapy, the biocompatibility and small size essential for permeating the blood-brain barrier make it a potential therapeutic drug candidate for treating AD.

Assessing the survival of exogenous plant microRNA in mice.

MicroRNAs (miRNAs), a class of small RNAs, are important molecules that influence several developmental processes and regulate RNA interference (RNAi), and are abundant in animals, plants, and plant tissues that are traditionally consumed in the diet. The survival of plant small RNAs from the diet in animals, however, remains unclear, and the persistence of miRNAs from dietary plants in the animal gastrointestinal (GI) tract is still under debate. In this study, ICR mice were fed plant total RNAs in quantities of 10-50 µg, extracted from Brassica oleracea. Serum, feces, and various tissues were collected from the mice after RNA consumption and analyzed for several miRNAs. Exogenous plant miRNAs were present in the sera, feces, and tissues of animals and these exogenous plant miRNAs were primarily acquired orally. MiR-172, the most highly enriched exogenous plant miRNA in B. oleracea, was found in the stomach, intestine, serum, and feces of mice that were fed plant RNA extracts including miR-172. The amount of miR-172 that survived passage through the GI tract varied among individuals, with a maximum of 4.5% recovered at the stomach of one individual, and had a range of 0.05-4.5% in different organs. Furthermore, miR-172 was detected in the blood, spleen, liver, and kidney of mice.

Effects of T-2 toxin on testosterone biosynthesis in mouse Leydig cells.

OBJECTIVE: To investigate the effects of T-2 toxin on testosterone biosynthesis in mouse Leydig cells. METHODS: Leydig cells isolated from clean and healthy Kunming male mice, whose concentration was adjusted to 5 × 10(5)/mL and the purity identified by the modified 3ß-hydroxysteroid dehydrogenase staining method, were used to establish a primary Leydig cell culture model. Blank control group (treated with 0 ng/mL human chorionic gonadotropin (hCG) and 0 mol/L T-2 toxin), inductive control group (treated with 10 ng/mL hCG and 0 mol/L T-2 toxin), low-dose T-2-toxin-exposure group (treated with 10 ng/mL hCG and 10(-9) mol/L T-2 toxin), middle-dose T-2 toxin-exposure group (treated with 10 ng/mL hCG and 10(-8) mol/L T-2 toxin) and high-dose T-2-toxin-exposure group (treated with 10 ng/mL hCG and 10(-7) mol/L T-2 toxin) were designed. The testosterone level was measured after 24 h incubation. RESULTS: After 24 h culture in liquid medium containing serum, the fresh isolated Leydig cells grew well and the purity exceeded 90%. By inducing 10 ng/mL hCG, the testosterone level of Leydig cells increased significantly and the difference compared with the blank control was of statistical sense. Compared with the inductive control group, the testosterone level of Leydig cells decreased, and the difference was of statistical sense in all T-2-toxin-exposure groups. Furthermore, the decrease was due to the increase in the dosage of T-2 toxin. CONCLUSIONS: T-2 toxin can directly decrease the testosterone biosynthesis in the primary Leydig cells derived from the mouse testis.

Heparinized polyvinyl alcohol to specifically adsorb low-density lipoprotein from plasma.

INTRODUCTION: A medical adsorbent for blood purification was developed to specifically adsorb low-density lipoprotein (LDL) from hypercholesterolemia patient's plasma by covalently immobilizing heparin onto the surface of polyvinyl alcohol (PVA) with the couplant toluence-2,4-diisocyanate (TDI). METHODS: We used IR to demonstrate the success of covalently immobilizing heparin onto the surface, and investigated its adsorption of LDL, and primarily evaluated its hemo-compatibility using tests for platelet adhesion, the degree of platelet activation and a hemolysis test. RESULTS: (1) Heparin was successfully covalently immobilized onto the surface, the maximum amount of heparin immobilized on the surface of 1g PVA-1799 granules was about 5 µg; (2) one optimal condition for adsorption of LDL from hyperlipidemia plasma was a pH within the range of 7.2∼9.5, accordingly the adsorptive ratio (adsorbent/g: plasma/L=1:2) for LDL was about 70%; (3) it exhibited good hemo-compatibility. CONCLUSION: The adsorbent results in satisfactory adsorption of LDL with good hemo-compatibility; it could potentially be used as a blood purification material, and immobilization of heparin onto medical materials may be a way to develop an LDL-specific adsorbent for blood purification.

Direct electron transfer and electrocatalysis of hemoglobin adsorbed on coralloid gold nanostructures.

Three-dimensional (3D) coralloid gold nanostructures (CGNs) have been fabricated by using an electrochemical growth method on the ITO glass substrates coated with agarose gel. Characterization by a variety of complementary techniques including scanning electron microscopy (SEM), X-ray diffraction (XRD), and UV-vis spectroscopy confirmed the distribution of CGNs on the ITO glass substrates. The adsorption behaviors of hemoglobin (Hb) on the CGNs-modified ITO (CGNs/ITO) electrodes were investigated by UV-vis spectroscopy and electrochemical methods, and the results demonstrated that 3D CGNs could provide good microenvironment for loading biomolecules and retaining their biological activity. Direct electron transfer of the adsorbed Hb exhibited a couple of stable and well-defined redox peaks centered at about -0.121 V and -0.041 V (vs. SCE) in 0.1 mol L(-1) pH 7.0 PBS. The electron transfer rate constant is 0.78 s(-1) at a scan rate of 0.1 V (s-1). The adsorbed Hb in the CGNs displayed a rapid amperometric response to the reduction of hydrogen peroxide (H2O2) for a broad linear range from 1.0 x 10(-6) mol LV(-1) to 5.0 x 10(-3) mol L(-1) with the detection limit of 3.0 x 10(-7) mol L(-1) (S/N = 3).

Preparation of heparin-immobilized PVA and its adsorption for low-density lipoprotein from hyperlipemia plasma.

In this study, heparin was covalently coupled by glutaraldehyde to Poly(vinyl alcohol) [PVA] in solid-liquid two-phase reaction system by two-step synthesis method to prepare a LDL-selective adsorbent. The parameters (the material ratio, reaction time and dosage of catalyzer) were investigated to evaluate their effect upon the immobilized amount of heparin onto the surface of PVA, IR was used to verify the covalent immobilization result and the heparin-modified PVA was also undergone the evaluation of its adsorption capability for low-density lipoprotein from hyperlipemia plasma, and its hemocompatibility was preliminarily evaluated by platelet adhesion test. Results showed: (1) under optimized reaction conditions the highest immobilization amount of heparin onto PVA surface within the experiments of this study has been obtained; (2) the optimized reaction conditions were: (i) at the refluxing temperature 78 degrees C; (ii) the material ratio of "PVA(g): 50% glutaraldehyde (ml)" was about "1:3"; (iii) the reaction time was about 5 h; and (iv) the amount of catalyzer (concentrated HCL) was about 1% of the 50% glutaraldehyde; (3) within the experiments of this study the highest immobilization amount would be up to 25 microg heparin on the surface of per g PVA granules; (4) the heparin-modified PVA granules showed significant adsorption for LDL under faintly alkaline environment (pH=7.2-9.5) ; (5) The result of platelet adhesion test showed no platelet adhered to its surface. Therefore, immobilization of heparin onto the surface of a support is one approach to prepare a kind of LDL adsorbent for blood purification.

Interfacial construction of gold nanoshells on 3-aminopropyl triethoxysilane modified ITO electrode surface for studying cytochrome b562 electrochemistry.

An interface of gold nanoshells (GNSs) was constructed on the surface of the 3-aminopropyl triethoxysilane (APTES) modified ITO glass substrates by a simple self-assemble method to form the GNSs-coated ITO electrode. UV-vis spectroscopy, scanning electron microscopy (SEM), and cyclic voltammetry were used to characterize the GNSs interface architectures. SEM and UV-vis spectroscopy showed that an interconnected and stable GNSs interface was formed on the APTES modified ITO glass substrate. The cytochrome b562 (Cyt b562) was selected to observe electron transfer reactions of redox protein at the GNSs-coated ITO electrodes. Quasi-reversible electrochemistry of Cyt b562 was obtained and its electrochemical behaviors were discussed.

Regenerating optical properties of individual gold nanoparticles in alcoholic solvents without any surfactant.

We compared the optical properties of gold nanoparticles (GNPs) in various solvents with those of strawberry-like composite particles (Au/SiO2) consisting of a silica core and single attached GNPs. The results show that Au/SiO2 without any surfactant could regenerate well optical properties of individual GNPs in alcoholic solvents. By the electrophoretic light-scattering measurements, the high dispersibility of Au/SiO2 composite particles dispersed in alcoholic solvents has been demonstrated. In addition, using Derjaguin-Landau-Verwey-Overbeek (DLVO) theory, we proposed a possible mechanism to qualitatively account for the dispersibility of Au/SiO2 in organic solvents such as alcoholic solvents and cyclohexane, which may provide an opportunity to manipulate optical signals of single nanoparticle in organic solvents.