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A mechanism exploration is an important part of toxicological studies. However, traditional cell and animal models can no longer meet the current needs for in-depth studies of toxicological mechanisms. The three-dimensional (3D) organoid derived from human embryonic stem cells (hESC) or induced pluripotent stem cells (hiPSC) is an ideal experimental model for the study of toxicological effects and mechanisms, which further recapitulates the human tissue microenvironment and provides a reliable method for studying complex cell–cell interactions. This article provides a comprehensive overview of the state of the 3D organoid technology in toxicological studies, including a bibliometric analysis of the existing literature and an exploration of the latest advances in toxicological mechanisms. The use of 3D organoids in toxicology research is growing rapidly, with applications in disease modeling, organ-on-chips, and drug toxicity screening being emphasized, but academic communications among countries/regions, institutions, and research scholars need to be further strengthened. Attempts to study the toxicological mechanisms of exogenous chemicals such as heavy metals, nanoparticles, drugs and organic pollutants are also increasing. It can be expected that 3D organoids can be better applied to the safety evaluation of exogenous chemicals by establishing a standardized methodology. [ABSTRACT FROM AUTHOR]

Silver nanoparticles (AgNPs) have been widely used in biomedicine and cosmetics, increasing their potential risks in neurotoxicity. But the involved molecular mechanism remains unclear. This study aims to explore molecular events related to AgNPs-induced neuronal damage by RNA-seq, and elucidate the role of Ca2+/CaMKII signal and Drp1-dependent mitochondrial disorder in HT22 cells synaptic degeneration induced by AgNPs. This study found that cell viabilities were decreased by AgNPs in a dose/time-dependent manner. AgNPs also increased protein expression of PINK1, Parkin, synaptophysin, and inhibited PGC-1 α , MAP2 and APP protein expression, indicating AgNPs-induced synaptic degeneration involved in disturbance of mitophagy and mitochondrial biogenesis in HT22 cells. Moreover, inhibition of AgNPs-induced Ca2+/CaMKII activation and Drp1/ROS rescued mitophagy disturbance and synaptic degeneration in HT22 cells by reserving aforementioned protein express changes except for PGC-1 α and APP protein. Thus, AgNPs-induced synaptic degeneration was mediated by Ca2+/CaMKII signal and Drp1-dependent mitochondrial disorder in HT22 cells, and mitophagy is the sensitive to the mechanism. Our study will provide in-depth molecular mechanism data for neurotoxic evaluation and biomedical application of AgNPs. [Display omitted] • Ca2+/CaMKII signal promotes AgNPs-induced mitophagy and synaptic degeneration in HT22 cells. • Drp1/ROS triggers AgNPs-induced mitochondrial disorder and synaptic degeneration. • Mitophagy is the sensitive to AgNPs-induced synaptic degeneration via Ca2+/CaMKII and Drp1/ROS signal. [ABSTRACT FROM AUTHOR]

The DNA tetrahedron has developed a broad spectrum of applications in biosensor construction thanks to its excellent mechanical rigidity and structural stability. However, how to construct a highly sensitive biosensor using a DNA tetrahedron is still a challenge. In this work, an ultrasensitive electrochemical biosensor based on a DNA tetrahedral nanostructure was developed with the help of synergy from proximity-dependent hybridization. To decrease the steric hindrance of DNA tetrahedra to proximity-dependent hybridization, the detection signal was set on the inclined side chain structure of a DNA tetrahedral sensing system. Additionally, when the target hybridized with the DNA probe, the ferrocene (Fc) labeled on the end of the DNA probe was driven close to the surface of the biosensor, providing a sensitive faradaic current. The experimental results exhibited a good linear relationship from 1 fM to 10 pM with a linear correlation coefficient of 0.9977, and a high sensitivity with a detection limit of 0.2 fM. Our DNA biosensor also showed good stability according to electrode characterization and target detection at different time scales and the anti-jamming capabilities in a complicated biological extraction environment were excellent. The electrochemical sensing system established here has greatly improved the detection sensitivity of a DNA biosensor based on a DNA tetrahedron, which will further promote its practical applications. [ABSTRACT FROM AUTHOR]

The value of superhydrophobicity in metal corrosion inhibition has generated wide interest due to the high repellent capability from the versatile surface. In this report, using a facile electrolysis approach, we have realized the superhydrophobic film onto Cu surface by the coordination with dodecanethiol based on an electrooxidation-deposition route. The as-formed film behaves as the prominent barrier for inhibiting the corrosion. After immersion in 3.5 wt.% NaCl aqueous solution for 15 days, this superhydrophobic surface still enables high corrosion prohibition effect to the underneath Cu with the inhibition efficiency reaching as high as 99.9%. [ABSTRACT FROM AUTHOR]

A facile and sensitive fluorescent strategy for the determination of dopamine is reported using 2, 3-diaminophenazine. Dopamine caused autooxidation in the presence of oxygen with catalysis by Mn2+and formed 2, 3-dihydro-1H-indole-5,6-dione. 2, 3-Diaminophenazine provided relatively strong fluorescence. 2, 3-Diaminophenazine in aqueous solution caused fluorescence quenching when the aminochrome condensed with 2, 3-diaminophenazine to allow the determination of dopamine. Under the optimized conditions, the linear dynamic range for dopamine was from 2.0 × 10−6 mol · L−1to 6.1 × 10−5 mol · L−1with a detection limit of 1.76 × 10−6 mol · L−1. [ABSTRACT FROM PUBLISHER]

Silver nanoparticles (AgNPs) have been incorporated in many consumer and biomedical products. Serious concerns have been expressed about the environmental and public health risks caused by nanoparticles. In previous studies, we found that AgNPs induced microglia polarization of the inflammatory phenotype. Autophagy was a critical for AgNPs-induced neuroinflammation. In the present study, we evaluated in detail the effects of AgNPs in different stages of the autophagy process, and we found that AgNPs induced neuroinflammatory responses and autophagic flux blockage both in the mouse brain and BV2 cells. AgNPs inhibited autophagosome-lysosome fusion and impaired the lysosomal functions by reducing the levels of lysosomal-associated membrane proteins, promoting lysosome membrane permeability and altering the lysosomal acidic microenvironment. These changes resulted in the defects in autophagic substrate clearance and subsequently led neuroinflammation. In addition, the elevation of autophagy could prevent the neuroinflammation induced by AgNPs. As a result, AgNPs hindered autophagic flux by inhibiting autophagosome fusion with lysosomes, thus aggravating the AgNPs-induced neurotoxicity. These findings will provide new insights to investigate the molecular mechanisms of neurotoxicity caused by AgNPs. [Display omitted] • AgNPs induced neuroinflammation and autophagic flux blockage in vivo & in vitro. • AgNPs inhibited autophagosome-lysosome fusion and impaired the lysosomal functions. • AgNPs hindered autophagic flux thus aggravating the AgNPs-induced neurotoxicity. • Autophagy might play a protective role in AgNPs-induced neuroinflammation. [ABSTRACT FROM AUTHOR]

Silver nanoparticles (AgNPs) could accumulate in the central nervous system (CNS) and induce neurotoxicity for their widespread use in industry and medicine. Mitochondria are vulnerable to toxicity of AgNPs, however, their role in the neurotoxicity remains unclear. This study aimed to evaluate AgNPs-induced synaptic degeneration in mouse hippocampal neurons (at a dose of 12–120 mg/kg BW via intravenous injection), and to further investigate mechanism of mitophagy, mitochondrial biogenesis process in the neurotoxicity. The results indicated that AgNPs accumulated in mouse hippocampal neurons and induced neurological deficits of learning and memory, which involved in synaptic degeneration accompanied with mitochondrial damage. Mechanistically, AgNPs exposure increased protein expression of PTEN-induced kinase 1 (PINK1), Parkin and inhibited peroxisome proliferator-activated receptor coactivator 1 alpha (PGC-1 α) protein expression, caused disturbed mitophagy and mitochondrial biogenesis. AgNPs also induced synaptic damage by increasing the protein expression of synaptophysin and decreasing PSD95, MAP2 protein expression. AgNPs exposure even promoted protein expression of amyloid precursor protein (APP) using in amyloid- β (A β) cleavage. Furthermore, AgNPs induced hippocampal neuronal synaptic degeneration, mitophagy and mitochondrial biogenesis is dependent on particle-specific AgNPs rather than released silver ions. Our research could provide insights into the regulatory mechanisms of AgNPs-induced neurotoxicity. This study will shed the light of neurotoxicological evaluation of nanoparticles and possible early warning of biomedical applications. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: A novel and sensitive electrochemical DNA biosensor was constructed based on the gold electrode modified by graphene and gold nanoparticles (AuNPs), whose sensitivity was improved by using 1,10-phenanthroline cobalt ([Co(phen)2(Cl)(H2O)]+) as an electroactive indicator. The gold electrode was firstly modified with sulfur graphene (GR-SH), and then covalently grafted with AuNPs via sulfur–gold affinity. Finally the thiol capped probe DNA was immobilized onto the AuNPs/GR modified electrode. The target DNA could hybridize with the probe DNA to form a double-stranded DNA (ds-DNA), into which [Co(phen)2(Cl)(H2O)]+ can intercalate, which can be confirmed by cyclic voltammetry (CV). The target DNA, from Escherichia coli (E. coil), could be detected in a linear range from 2.50×10−11 to 1.25×10−9 M (R =0.9981) with a detection limit of 8.33×10−12 M (3σ, n =11). It was demonstrated that the reported electrochemical DNA biosensor offered a promising approach for the sensitive and selective detection of DNA by using [Co(phen)2(Cl)(H2O)]+ as an electroactive indicator. [Copyright &y& Elsevier]

A novel fluorescence assay, based on the signal amplification through cycling reactions of aptameric recognition and nucleic acid exo-cleaving, was established for the sensitive detection of cocaine. In this assay, a new single fluorophore-labeled DNA-hairpin probe was used. This smart probe was established based on the significant nucleobase quenching between the nucleobases and the fluorophore. In the presence of cocaine and its aptamer, the structure of the smart probe changed to recover the fluorescence. In order to enhance the sensitivity of this assay, exonuclease III was introduced to enable the inputted cocaine to react with multiple probes in a recycling manner. Under the optimal conditions, a linear range for cocaine from 4.0 × 10−9 to 8.0 × 10−8 M with a detection limit of 1.76 × 10−9 M (3σ, n = 11) was obtained. [ABSTRACT FROM PUBLISHER]

Abstract: A sensitive and specific sandwich assay for the detection of thrombin is described. Two affiliative aptamers were used to increase the assay specificity through sandwich recognition. Recognition DNA loaded on gold nanoparticles (AuNPs) partially hybridized with the initiator DNA, which was displaced by surviving DNA. After the initiator DNA was released into the solution, one hairpin structure was opened, which in turn opened another hairpin structure. The initiator DNA was displaced and released into the solution again by another hairpin structure because of the hybridized reaction. Then the released initiator DNA initiated another autocatalytic strand displacement reaction. A sophisticated network of three such duplex formation cycles was designed to amplify the fluorescence signal. Other proteins, such as bovine serum albumin and lysozyme, did not interfere with the detection of thrombin. This approach enables rapid and specific thrombin detection with reduced costs and minimized material consumption compared with traditional assay processes. The detection limit of thrombin was as low as 4.3×10−13 M based on the AuNP amplification and the autocatalytic strand displacement cycle reaction. This method could be used in biological samples with excellent selectivity. [Copyright &y& Elsevier]

Abstract: An ultrasensitive fluorescence detection method for DNA based on nicking endonuclease (NEase) and target recycles assisted with CdTe quantum dots (QDs) is reported. In the detection system, when the target DNA is present, it hybridizes with a linker strand to from a duplex, in which the NEase recognizes specific nucleotide sequences and cleaves the linker strand. After nicking, the fragments of the linker strand spontaneously dissociate from the target DNA and another linker strand hybridizes to the target to trigger another strand-scission cycle. On the other hand, when the target was absent, no duplex is formed and no fragment of linker strand is produced. Then CdTe QDs and magnetic beads (MBs), which were all modified with DNA sequences complementary to that of the linker strands are added to the solution to detect the presence of a target DNA. The signal was generated through the difference in Förster resonance energy transfer (FRET) between the MB and CdTe QDs. This method indicates that one target DNA leads to cleavage of hundreds of linker DNA, increasing detection sensitivity by nearly three orders of magnitude. This method should be applicable whenever there is a requirement to detect a specific DNA sequence and can also be used for multicomponent detection. [ABSTRACT FROM AUTHOR]

Abstract: A novel and sensitive electrochemical DNA biosensor has been developed for the detection of DNA hybridization. The biosensor was proposed by using copper(II) complex of Luteolin C30H18CuO12 (CuL2) as an electroactive indicator based on silver nanoparticles and multi-walled carbon nanotubes (Ag/MWCNTs) modified glassy carbon electrode (GCE). In this method, the 4-aminobenzoic acid (4-ABA) and Ag nanoparticles were covalently grafted on MWCNTs to form Ag/4-ABA/MWCNTs. The proposed method dramatically increased DNA attachment quantity and complementary ssDNA detection sensitivity for its large surface area and good charge-transport characteristics. DNA hybridization detection was performed using CuL2 as an electroactive indicator. The CuL2 was synthesized and characterized using elemental analysis (EA) and IR spectroscopy. Cyclic voltammetry (CV) and fluorescence spectroscopy were used to investigate the interaction between CuL2 and ds-oligonucleotides (dsDNA). It was revealed that CuL2 presented high electrochemical activity on GCE, and it could be intercalated into the double helices of dsDNA. The target ssDNA of the human hepatitis B virus (HBV) was quantified in a linear range from 3.23×10−12 to 5.31×10−9 M (r =0.9983). A detection limit of 6.46×10−13 M (3σ, n =11) was achieved. [Copyright &y& Elsevier]

Abstract: A Mn(II) complex, MnL (L=sodium (E)-3-((1-carboxyethylimino)methyl)-4-hydroxybenzenesulfonate), was synthesized and characterized using elemental analysis and IR spectroscopy. Cyclic voltammetry (CV) and fluorescence spectroscopy were used to investigate the interaction between MnL and salmon sperm DNA. It was revealed that MnL presented high electrochemical activity on glassy carbon electrode (GCE), and it could be intercalated into the double helices of double-stranded DNA (dsDNA). Using MnL as the hybridization indicator, a novel and sensitive electrochemical DNA biosensor based on multiwall carbon nanotubes functionalized with carboxyl groups (MWCNTs–COOH, on which DNA probes were covalently immobilized) was prepared. The target single-stranded DNA (ssDNA) could be quantified ranging from 6.7×10−10 M to 8.4×10−9 M with good linearity (r =0.9922). A detection limit of 1.4×10−10 M (3σ, n =9) was achieved. [Copyright &y& Elsevier]

Abstract: The manganese complex of rutin(R) C54H58MnO32 (abbreviated by MnR2) was synthesized and characterized by elemental analysis and IR spectroscopy. Cyclic voltammetry (CV) and fluorescence spectroscopy were used to investigate the interaction of MnR2 with salmon sperm DNA. It was revealed that MnR2 presented an excellent electrochemical activity on glassy carbon electrode (GCE) and could intercalate into the double helix of double-stranded DNA (dsDNA). A novel and sensitive electrochemical DNA biosensor based on multi-walled carbon nanotubes functionalized with a carboxylic acid group (MWCNTs–COOH) for covalent DNA immobilization and enhanced hybridization detection was described. The MWCNTs–COOH modified glassy carbon electrode was fabricated and oligonucleotides with the 5′-amino group were covalently bonded to the carboxyl group of carbon nanotubes. Compared with DNA sensors with oligonucleotides directly incorporated on glassy carbon electrodes, this carbon nanotube-based assay with its large surface area and good charge-transport characteristics dramatically increased DNA attachment quantity and complementary ssDNA detection sensitivity. The target ssDNA could be quantified ranged from 1.60×10−9 M to 4.80×10−8 M with good linearity (r =0.9898) and a detection limit of 3.81×10−11 M (3σ, n =7) was achieved by the constructed electrochemical DNA biosensor. [Copyright &y& Elsevier]

Abstract: In this work, the complex cadmium(II)–morin was synthesized and its interaction with double-stranded salmon sperm DNA was studied by electrochemical methods on glassy carbon electrode (GCE). It was shown that Cd(II)–Morin with high electrochemical activity can intercalate into the double-helix DNA, and the binding stoichiometry and equilibrium dissociation constant according to the Hill model for cooperative binding were calculated to be 1.761 and 2.5×10−5 M, respectively. Using Cd(II)–Morin as a novel hybridization indicator, the hybridization between the probe and its complementary and mismatched sequence was investigated by differential pulse voltammetry (DPV), which was to access the selectivity of the developed electrochemical DNA biosensor. The complementary target ssDNA could be quantified over the range from 2.69×10−8 M to 9.16×10−7 M with a linear correlation of 0.9971 and a detection limit of 9.30×10−9 M. These results demonstrated that the Cd(II)–Morin indicator provides great promise for the rapid and selective measurement of the target DNA. [Copyright &y& Elsevier]

A sensitive and selective fluorescence assay for DNA methyltransferase (MTase) activity detection was designed based on aggregation-induced emission (AIE) and target initiated template-free DNA polymerization. Quaternized tetraphenylethene salt was synthesized as the AIE probe, which binds to single-stranded DNA by electrostatic interaction. A hairpin probe was designed with a specific sequence for DNA MTase. In the presence of DNA MTase, the methylation reaction initiated DNA polymerization with terminal deoxynucleotidyl transferase (TdT), which activated the fluorescence intensity through AIE. The designed DNA sensor displayed a linear response to concentrations of DNA adenine methyltransferase (Dam) MTase from 0.5 U·mL−1 to 100 U mL−1, with a limit of detection of 0.16 U mL−1. The assay was also effective for detection of DNA MTase activity in human serum and for showing the inhibitory effect of 5-fluorouracil on Dam MTase. Schematic presentation of fluorescent detection of DNA methyltransferase (MTase) activity. Aggregation-induced emission (AIE) and target initiated template-free DNA polymerization were used in this assay, and the detection limit was 0.16 U mL−1. Image 1 • Aggregation-induced emission effect was used in this strategy. • Terminal deoxynucleotidyl transferase was employed for DNA polymerization. • This assay exhibits an excellent specificity and is successfully applied in real sample assay. [ABSTRACT FROM AUTHOR]

In this work, a new 3D DNA nanosphere was ingeniously designed and fabricated, which was used to combine with multiple enzyme-free amplification strategy to develop a photoelectrochemical (PEC) biosensing platform for ultrasensitive detection of carcinoembryonic antigen (CEA). The 3D DNA nanostructure was self-assembled by base complementary pairing in a few minutes and rolling circle amplification (RCA) reaction. The intense photocurrent derived from Au NPs/ZnSe QDs can be effectively decreased by 3D DNA nanospheres assembled on the electrode, making photoelectric signal present "off" state. The specific binding of target CEA with its hairpin (HP1) aptamer opens HP1 structure, which initiated multiple enzyme-free strand displacement amplification (SDA) reaction and generated a large number of single strands DNA S1. Then S1 competitively binds to capture DNA on the electrode to release 3D DNA nanospheres, thus the photocurrent signal became "on" state for achieving amplified assay of target CEA. The proposed PEC biosensor exhibits excellent performance with a wide linear range of 1.0 fg/mL to 10 ng/mL and a low detection limit of 0.12 fg/mL for CEA, which was successfully applied for the assay of real serum samples with good precision. The reported strategy opens a new simple way for PEC biosensor using DNA nanostructure, showing huge potential in clinical application research. • A novel 3D DNA nanostructure was assembled by base complementary pairing and RCA reaction. • A new "on-off-on" PEC biosensor based on ZnSe QDs and 3D DNA nanosphere was designed for CEA detection. • The photocurrent from ZnSe QDs can be effectively reduced by 3D DNA nanospheres for signal "Off" state. • The CEA-induced recycling amplification was introduced to achieve sensitive PEC "On" detection of CEA. [ABSTRACT FROM AUTHOR]

In this paper, an effective and accurate ratiometric electrochemiluminescence (ECL) system based on Au-luminol and CdS quantum dots (CdS QDs) as signal probes was constructed for detecting carcinoembryonic antigen (CEA). Polyaniline (PANI) and gold nanoparticles (AuNPs) strongly enhanced the electronic transfer efficiency and the specific area of the modified sensing surface, and improved the detection sensitivity. CdS QDs functionalized DNA strands functioned as cathode ECL emitters, and the aptamer of CEA modified with Au-luminol and quencher cyanine dye (Cy5) fluorophore functioned as anode ECL emitters. After the DNA capture probe combined with CEA aptamer, the negative potential ECL response of the CdS QDs was quenched because of electrochemiluminescence resonance energy transfer (ERET) between the Cy5 fluorophore and CdS QDs. However, the positive potential ECL response of Au-luminol can still be detected. The negative potential ECL response of CdS QDs was recovered, and the positive potential ECL response of Au-luminol decreased after CEA combined with its aptamer to take Cy5 and Au-luminol off the sensing interface. Additionally, the peptide provided effective anti-fouling performance in the detection of complex samples. The ratiometric ECL sensor with anti-fouling ability can sensitively determine the concentration of CEA in human serum. In this paper, an effective and accurate ratiometric electrochemiluminescence (ECL) system based on designed anti-fouling peptide was constructed for detecting carcinoembryonic antigens (CEA) in complex samples with high selectivity and good sensitivity. Image 1 • Electrochemiluminescence resonance energy transfer (ERET) was used to construct the ratiometric ECL biosensor. • Ratiometric signal used in the ECL biosensor improved the accuracy of carcinoembryonic antigen detection. • Conductive polyaniline and gold nanoparticles enhanced the sensitivity of the modified electrode. • Antifouling peptide enabled this sensor to detect carcinoembryonic antigen in complex sample such as human serum. [ABSTRACT FROM AUTHOR]

We designed a dual-color fluorescent nanoprobe for simultaneous detection and imaging of adenosine triphosphate and glutathione in living cells based on porous carbon nanospheres and a DNA hybrid hydrogel. Due to the non-template synthesis process and good biocompatibility, the nanohydrogel displayed a short preparation time and anti-nonspecific adsorption. [ABSTRACT FROM AUTHOR]

The present study shows that a dual-signal nanoprobe consisting of DNAzyme-functionalized porous carbon nanospheres (PCNs) responds to microRNA-21 and zinc ion (Zn2+). The fluorescent probe undergoes an increase in the fluorescence intensity of fluorescein isothiocyanate (FITC) (with excitation/emission wavelengths at 488/517 nm) and the fluorescence intensity of cyanine-5 (Cy5) (with excitation/emission wavelengths at 633/670 nm) in the presence of microRNA-21 and Zn2+. The recognition between microRNA-21 and its complementary strand in the PCNs induces the separation of Zn2+-specific DNAzyme from PCNs, thus resulting in the increase of green fluorescence, and the exogenous Zn2+ triggers the rupture of cleavage strand of DNAzyme and recovery of red fluorescence. This nanoprobe allows us to acquire in vitro the determination of microRNA-21 in the range of 2–300 nM with a detection limit of 0.57 nM and the determination of Zn2+ in the range 2–100 nM with a detection limit of 0.43 nM, and in situ simultaneous imaging in MCF-7 breast cancer cells. Therefore, this strategy permits to obtain the expression levels of different biomarkers in living cells, providing a useful tool for diagnosis of cancers and understanding their biological process. [ABSTRACT FROM AUTHOR]

Generated from plastics, microplastics (MPs) and nanoplastics (NPs) are difficult to completely degrade in the natural environment, which can accumulate in almost all lives. Liver is one of the main target organs. In this study, HepG2 and L02 cells were exposed to 0–50 μg/mL polystyrene (PS)-NPs to investigate the mechanism of mitochondrial damage and inflammation. The results showed mitochondria damage and inflammatory caused by NPs, and it can be inhibited by N-acetyl-L-cysteine (NAC). In addition, reactive oxygen species (ROS) activated nuclear factor erythroid-derived factor 2-related factor (Nrf2) pathway. Nrf2 siRNA exacerbated the injury, suggesting Nrf2 plays a protective role. Moreover, p62 siRNA increased ROS and mitochondrial damage by inhibiting Nrf2, but didn't affect the inflammation. In conclusion, Nrf2 was activated by ROS and played a protective role in PS-NPs-mediated hepatotoxicity. This study supplemented the data of liver injury caused by PS-NPs, providing a basis for the safe disposal of plastics. [Display omitted] • Polystyrene nanoplastics (PS-NPs) decreased in the viability of HepG2 and L02 cells in a dose and time-dependent manner. • PS-NPs induced oxidative, mitochondria damage and inflammation in HepG2 and L02 cells. • N-acetylcysteine (NAC) alleviated PS-NPs-induced oxidative and inflammation in HepG2. • Nrf2 protected HepG2 from PS-NPs-induced oxidative, mitochondria damage and inflammation. • p62 siRNA aggravated PS-NPs-induced oxidative and mitochondria damage in HepG2. [ABSTRACT FROM AUTHOR]

Herein, we have designed a ratiometric fluorescent nanoprobe for adenosine triphosphate sensing and imaging in living cells, based on silica nanoparticles and a DNA-functionalized hybrid hydrogel. This ratiometric detecting method could validly avoid false-positive signals. Due to its controllable size, favorable biocompatibility and biostability, the nanohydrogel exhibited high cellular permeability and fast response in living cells. [ABSTRACT FROM AUTHOR]

Microplastics have become a serious environmental pollutant and subsequently have harmful effects on human health. Thus, the impacts of microplastics on human cells need to be explored. In the present study, the cytotoxic effects at the subcellular-organelle levels to polystyrene nanoplastics (PS-NPs, diameter 21.5 ± 2.7 nm) were investigated in the human hepatocellular carcinoma (HepG2) cell line. The cell viability exposed to PS-NPs at the concentrations of 6.25, 12.5, 25 and 50 μg/mL for 24 h diminished in a concentration-dependent manner. The PS-NPs treatment induced mitochondrial injuries, including morphological changes, decreased adenosine triphosphate (ATP) production and the loss of mitochondrial membrane potentials (MMP). The PS-NPs treatment could further spark cell apoptosis by upregulating caspase 3, caspase 9, cytochrome c , and Bcl-2 associated X protein (Bax)/B-cell lymphoma-2 (Bcl-2) in HepG2 cells, which is related to the mitochondrial dysfunction. PS-NPs exposure stimulated the excessive cellular reactive oxygen species (ROS) production and also induced mitochondrial fission by upregulating dynamin-related protein 1 (DRP1) and P-DRP1, but downregulating optic atrophy protein 1 (OPA1) and peroxisome proliferator-activated receptor-gamma coactivator-1alpha (PGC-1α) expression levels. The above effects on mitochondria damage induced by PS-NPs were reversed by the pretreatment of N-acetylcysteine (NAC), mitochondrial division inhibitor 1 (Mdivi-1) and DRP1 siRNA. The results suggested that the interaction between ROS and DRP1-dependent mitochondrial division could promote mitochondrial lesions and mitochondria-related apoptosis caused by PS-NPs. These findings on molecular mechanisms provide a theoretical basis for preventing the hazards caused by microplastics to human health. [Display omitted] • PS-NPs decreased viability of HepG2 cells in a concentration-dependent manner. • PS-NPs induced oxidative stress and apoptosis in HepG2 cells. • PS-NPs induced mitochondrial morphological, function, dynamics injury in HepG2 cells. • NAC alleviated PS-NPs-induced cytotoxicity and mitochondrial injury. • Mdivi-1 and DRP1 siRNA relieved PS-NPs-induced cytotoxicity mitochondrial injury. [ABSTRACT FROM AUTHOR]

Silver nanoparticles (AgNPs) are widely used in various fields such as industry, agriculture, and medical care because of their excellent broad-spectrum antibacterial activity. However, their extensive use has raised concerns about their health risks. Liver is one of the main target organs for the accumulation and action of AgNPs. Therefore, evaluating the toxic effects of AgNPs on liver cells and its mechanisms of action is crucial for the safe application of AgNPs. In the study, polyvinylpyrrolidone (PVP)-coated AgNPs were characterized. The human hepatoma cell line (HepG2) and the normal hepatic cell line (L02) were exposed to different concentrations of AgNPs (20–160 μg/mL) and pretreated with the addition of N -acetylcysteine (NAC) or by Nrf2 siRNA transfection. NAC was able to inhibit the concentration-dependent increase in the level of apoptosis induced by AgNPs in HepG2 cells and L02 cells. Interestingly, HepG2 cells were more sensitive to AgNPs than L02 cells, and this may be related to the different ROS generation and responses to AgNPs by cancer cells and normal cells. In addition, NAC also alleviated the imbalance of antioxidant system and cell cycle arrest, which may be related to AgNPs-induced DNA damage and autophagy. The knockdown of nuclear factor erythroid-derived factor 2-related factor (Nrf2) found that AgNPs-induced ROS and apoptosis levels were further upregulated, but the cell cycle arrest was alleviated. On the whole, Nrf2 exerts a protective role in AgNPs-induced hepatotoxicity. This study complements the hepatotoxicity mechanisms of AgNPs and provides data for a future exploration of AgNPs-related anti-hepatocellular carcinoma drugs. [Display omitted] • AgNPs induced a concentration-dependent decline in HepG2 and L02 cells viability. • AgNPs induced ROS increase and apoptosis in HepG2 and L02 cells. • AgNPs induced DNA damage, autophagy and cell cycle arrest in HepG2 and L02 cells. • N -acetylcysteine alleviated AgNPs-induced cytotoxicity in HepG2 and L02 cells. • Nrf2 siRNA aggravated AgNPs-induced cytotoxicity in HepG2 and L02 cells. [ABSTRACT FROM AUTHOR]

In this report, a strategy based on an aptameric molecule switch to realize homogeneous and isothermal signal exponential amplification and protein detection has been described. This method was simple and sensitive, allowing detection of as low as 2.6 × 10−12 M thrombin. [ABSTRACT FROM AUTHOR]

We report on an electrochemical immunoassay for simultaneous detection of the tumor markers carcinoembryonic antigen (CEA) and α-fetoprotein (AFP). Gold nanoparticles (AuNPs) were synthesized inside the internal pore walls of mesoporous silica (MPS). Then, Methylene blue (MB) and 6-ferrocenylhexanethiol (FeC), which act as electrochemical substrates, were incorporated into the channels via the formation of Au-S bonds. Finally, monoclonal antibodies against CEA (anti-CEA) and AFP (anti-AFP) were immobilized in the channels of MB-AuNPs-MPS and FeC-AuNPs-MPS, respectively. Suspensions of anti-CEA/MB-AuNPs-MPS and of anti-AFP/FeC-AuNPs-MPS were deposited on two different sites of the ITO electrode. When incubated with samples containing the two analytes, the formation of electrically nonconductive immunoconjugates blocks electron transfer. Simultaneous detection of CEA and AFP was accomplished by monitoring the current change before and after an immunoreaction has occurred. The AuNPs confined inside the channels are promoting the electron transport and thus improve detection limits. The immunoelectrode responds to CEA in the 0.5-50 ng mL concentration range, and to AFP in concentrations between 0.5 and 100 ng mL. The detection limits (at an S/N of 3) are 0.1 ng mL in both cases. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Abstract: In this work, we prepared a new electrochemiluminescent signal probe using a small bifunctional composite quantum dot (QD) with intense electrochemiluminescence (ECL) and excellent magnetic property, and developed a sensitive ECL biosensor for detection of cancer cells via DNA cyclic amplification technique. The graphene oxide (GO) with unique electrical properties was used as nano-amplified platform to immobilize a large number of capture DNA (c-DNA1). The endonuclease-assisted amplification technique was applied to amplify the ECL signal change induced by target cells. Specifically, the bifunctional composite QDs with excellent magnetic property can be conveniently labeled, separated, and developed the ECL signal probe, thus an ECL method for rapid and sensitive detection of cancer cells was developed. So far, it is for the first time that the small magnetic electrochemiluminescent QDs were applied to the assays of cancer cells by using amplification strategy, which is expected to have great potential for early clinical diagnosis of cancer. [Copyright &y& Elsevier]

As the release of silver nanoparticles (AgNPs) in the environment continues to increase, great concerns have been raised about their potential toxicity to humans. It is urgent to assess the possible toxicity of AgNPs to the immune cells of the central nervous system due to the continuous accumulation of AgNPs in the brain. This study aimed to evaluate the neurotoxicity of AgNPs and the regulatory mechanism of autophagy in AgNPs-induced inflammation by using mouse microglia BV2 cell lines. AgNPs decreased the microglia cell activity in a concentration and time-dependent manner. The exposure of BV2 cells to AgNPs at a non-cytotoxic level of 5 μg/mL resulted in increase of pro-inflammatory cytokines and decrease of mRNA expression of anti-inflammatory cytokines. AgNPs exposure increased M1 markers of iNOS expression and decreased the expression of M2 markers of CD206 in a time-dependent manner. Meanwhile, the expression of inflammatory proteins IL-1β and NF-κB increased significantly. Additionally, AgNPs induced an increase in autophagosome and upregulation of LC3II, Beclin1, and p62 expression levels. Pretreatment by an autophagy inhibitor, 3-Methyladenine, caused more AgNPs-treated microglia to polarized into pro-inflammatory phenotypes. Inhibition of autophagy also increased the expression of inflammation-associated mRNA and proteins in BV2 cells. These results indicated that AgNPs could induce pro-inflammatory phenotypic polarization of microglia and the autophagy could play a key regulatory role in the pro-inflammatory phenotypic polarization of microglia induced by AgNPs. [Display omitted] [ABSTRACT FROM AUTHOR]

Highlights • Three-way junction structure was applied to highly selective detection of miRNA. • A novel free-running DNA walker was used to the amplified ECL detection of miRNA. • The cascade amplification strategy was applied for ultrasensitive miRNA detection. • A highly sensitive miRNA-21 detection with low limit of 1.5 fM was achieved. Abstract In this work, a target-triggered three-way junction (3-WJ) structure was combined with enzyme-powered cascade amplification strategy for ultrasensitive electrochemiluminescence (ECL) detection of microRNA via free-running DNA walker. In the presence of target microRNA-21 (miRNA-21), a three-way junction structure was formed to trigger enzyme-aided multiple DNA amplification, and thus exponentially amplified triggers were generated. Then, the trigger DNA could hybridize with the blocking DNA on the electrode to release walker DNA, which specifically combined with the quantum dots (QDs)-DNA probe, and formed a recognition site for Nt.BbvCI. The movement of DNA walker is powered by the nicking endonuclease that cleaves specific QDs-DNA probes on the track. Thus one walker DNA can automatically cleave multiple QDs probes on the electrode during the movement, resulting in significantly amplified changes of ECL signal, which could be used for the highly sensitive detection of target miRNA-21. Under the optimal conditions, the ECL signal change is linear with the concentration of miRNA-21 in the range from 10−14 M to 10-7 M with a detection limit of 1.5 fM. This newly established strategy could achieve rapid, isothermal, and homogeneous signal amplification for specific nucleic acids in complicated biomatrix, which hold great potential for application in early clinical diagnosis. [ABSTRACT FROM AUTHOR]

Optical sensors having transparent windows act as the eyes in marine exploration. However, biofouling is a critical problem to blind them. In this report, transparent glass is used as the substrate to grow robust SiO 2 onto the surface via a facile breath figure approach under the temperature of 40 °C. After grafting of long-chain organic molecule, a hydrophobic surface is obtained. The three-dimensional interconnecting net configuration acts as the reservoir for accommodating the lubricant to form the liquid-infused surface. After lubrication with oil phase, SiO 2 performs as the transparent medium for light to transmit. Taking diatom as the representative organism, the surface can effectively inhibit biofouling growth. Time-dependent fluorescent images are used to trace the inhibition effect of the liquid-infused surface. Even immersed in seawater for 11 days, the inhibition efficiency can still maintain 96.1%. [ABSTRACT FROM AUTHOR]

A novel nonenzymatic sensor based on gold nanoparticle-nitrogen-doped graphene was synthesized by electrochemical sequential deposition on the surface of a glassy carbon electrode. Nitrogen-doped graphene was synthesized by a hydrothermal method using graphene oxide and carbamide as the raw materials mixed in specific proportions. The gold nanoparticles were used in the electrochemical sensor to provide unique electronic and electrochemical properties. Under the optimized conditions, hydrogen peroxide was determined by differential pulse voltammetry with a linear relationship for concentrations from 1.0 × 10−7 to 1.0 × 10−5 mol L−1. The detection limit was 4.9 × 10−8 mol · L−1 (according to the 3σ rule) and the recoveries were 95.0-98.0%. This sensor is simple, reproducible, and demonstrates that nitrogen-doped graphene oxide has potential applications for electrochemical sensors. [ABSTRACT FROM AUTHOR]

In the present work, we designed a unique enzyme-aided multiple amplification strategy for sensitive electrochemiluminescence (ECL) detection of DNA by using the amplified gold nanoparticles (GNPS)-polyamidoamine (PAMAM)-CdSe quantum dots (QDs) signal probe. Firstly, the novel GNPS-PAMAM dendrimers nanostructure with good biocompatibility and electroconductibility contains many amino groups, which can load a large number of CdSe QDs to develop amplified ECL signal probe. Then, the presence of target DNA activated the enzyme-assisted polymerization strand-displacement cycling reaction, and a large number of the hairpin template was opened. Subsequently, the opened stem further interacted with the capture hairpin (HP) DNA on the electrode, and the GNPS-PAMAM-CdSe signal probe hybridized with the exposed stem of the HP to trigger the second new polymerization reaction. Meanwhile, the first cycle was generating abundant DNA triggers which could directly open the template. As a result of the cascade amplification technique, a large number of CdSe QDs signal probe could be assembled on the electrode, generating much amplified ECL signal for sensitive detection of target DNA. Thus, this novel QDs-based amplified ECL strategy holds great promise for DNA detection and can be further exploited for sensing applications in clinical diagnostics. [ABSTRACT FROM AUTHOR]

A one-step, rapid, and visual method was developed for the detection of RNA viruses and a few copies of the Zika RNA virus were directly detected within 25 min by naked-eye observation. This method will prove to be promising for point-of-care testing in out-of-lab and inconvenient settings. [ABSTRACT FROM AUTHOR]

A strand exchange amplification (SEA) method to detect foodborne pathogen Listeria monocytogenes was developed. SEA is a novel nucleic acid amplification method that only requires one pair of primers. The specie-specific primers were designed by targeting the 16S rRNA gene and the amplification reaction was performed as short as 60 min at 61 °C. Notably, SEA method could not only detect genomic DNA but also detect RNA by one step without requiring extra reverse transcription. The result could be visualized by naked eyes so that water bath pot would be the only equipment needed. Moreover, culture fluids and bacteria colony could be successfully detected without any pretreatment and the method displayed good specificity and strong anti-jamming capacity. These features greatly simplified the operating procedure and made SEA method be potential for developing point-of-care testing (POCT) devices to detect viable L. monocytogenes. [ABSTRACT FROM AUTHOR]

A polythiophene–graphene oxide compound membrane and Prussian blue were deposited sequentially on the surface of a glassy carbon electrode by cyclic voltammetry. Due to its excellent electrocatalysis and its analogy with peroxidase enzymes, Prussian blue has been widely used in amperometric biosensors. The polythiophene–graphene oxide compound membrane exhibited good electroconductibility and a large specific surface area. The fabricated Prussian blue/polythiophene/graphene oxide/glassy carbon electrode was characterized by transmission electron microscopy, scanning electron microscopy, and cyclic voltammetry. Under the optimal experimental conditions, the detection of hydrogen peroxide was studied by its amperometric current–time curve. Due to the presence of polythiophene–graphene oxide compound membrane and Prussian blue, the hydrogen peroxide sensor shows a linear calibration range of 1.0 × 10−6–1.0 × 10−4 mol L−1, detection limits of 3.2 × 10−7 mol L−1at a signal-to-noise ratio of 3, and recoveries from 95.0 to 105.0%. The results show that the modified glassy carbon electrode has potential practical application for the determination of hydrogen peroxide based on its sensitivity and long-term stability. [ABSTRACT FROM PUBLISHER]

In this report, a facile approach combining both galvanic dealloying and chemical vapor deposition is proposed to enable the slippery liquid-infused porous surface (SLIPS) onto CuZn alloy. Firstly, CuZn is dealloyed with CuSO 4 aqueous solution, and a porous Cu 2 O surface is achieved via a dealloying-deposition route. The surface is modified with dodecanethiol to realize the superhydrophobicity. The infusion of oil phase is assisted by the spin coating technique, and SLIPS is finally obtained, showing prominent corrosion inhibition capability with the corrosion current density decreasing to 1/500 of the bare CuZn. Moreover, SLIPS shows high resistance to multiple cycles of electrical field with wide anodic and cathodic window. To external mechanical damage, such as cutting and erosion in seawater, SLIPS behaves good self-healing capability. Even after cutting or drilling the surface for many times, the corrosion inhibition can still be maintained, indicating that the coating constructed by self-healing fluid has high tolerance to external mechanical damage. [ABSTRACT FROM AUTHOR]

A novel strategy using Ag nanoparticles-3D (AgNPs-3D) nanostructure enhanced electrochemiluminescence (ECL) of CdSe quantum dots (QDs) coupled with strand displacement amplification (SDA) for sensitive biosensing of DNA was successfully designed. The prepared CdSe QDs with intense ECL were assembled on the poly (diallyldimethylammonium chloride) (PDDA) graphene oxide (GO) nanocomposites modified electrode, then gold nanoparticles (NPs) as the quenching probe was conjugated to the QDs, ECL signal was efficiently quenched. The target DNA induced cycling SDA and generated a large number of DNA s1. The released DNA s1 could open the hairpin DNA with quenching probe. So the presence of low levels of target DNA can potentially result in a significant enhancement of ECL signal. Furthermore, large number of AgNPs were then in situ reduced in the 3D DNA skeleton on the electrode, which dramaticlly enhanced ECL signal of QDs owing to the excellent electrical conductivity, and the much amplified ECL signal change has a quantitative relation with the target DNA. So by combining the AgNPs-3D nanostructure and cycling SDA to achieve greatly amplified detection of DNA, the promising ECL strategy could provide a highly sensitive platform for various biomolecules and has a good prospect for clinical diagnosis in the future. [ABSTRACT FROM AUTHOR]

A new selective fluorescent chemosensor based on rhodamine 6G derivative ( R1 ) has been designed and synthesized, which displayed highly selective and sensitive detecting for lead ion in aqueous solution. Sensor R1 was selective toward Pb 2+ ion by a light yellow to pink change for the visual detection of Pb 2+ ion. The fluorescence recognition processes of Pb 2+ was based on a binding induced ring-opening from the spirolactam (nonfluorescent) to acyclic xanthenes (fluorescent). Sensor R1 was excited with a 1:1 binding ratio and the linear response in the range of 1.0 × 10 −8 –1.0 × 10 −5 mol L −1 with the limit of detection of 2.7 × 10 −9 mol L −1 (3σ/slope). [ABSTRACT FROM AUTHOR]

An ultrasensitive biosensor for alpha-fetoprotein was developed based on electrochemically synthesized polyaniline (PANI) nanowires, which were functionalized with gold nanoparticles (AuNPs) and polyethylene glycols (PEG). The prepared PEG/AuNPs/PANI composite, combining the electrical conductivity of the AuNPs/PANI with the robust antifouling ability of PEG, offered an ideal substrate for the development of low fouling electrochemical biosensors. Alpha-fetoprotein (AFP), a well-known hepatocellular carcinoma biomarker, was used as a model analyte, and its antibody was immobilized on the PEG/AuNPs/PANI for the construction of the AFP immunosensor. Using the redox current of PANI as the sensing signal, in addition to the good biocompatibility of PEG/AuNPs and the anti-biofouling property of PEG, the developed immunosensor showed improved biosensing performances, such as wide linear range and ultralow detection limit (0.007 pg mL −1 ). More importantly, it is label-free, reagentless and low fouling, making it capable of assaying AFP in real serum samples without suffering from significant interference or biofouling. [ABSTRACT FROM AUTHOR]

Conducting polymer polyaniline (PANI) nanowire arrays were electrochemically in situ synthesized on the surface of glassy carbon electrodes, which were modified with self-assembled multi-walled carbon nanotubes (CNTs) networks. The ordered PANI nanowire arrays and CNTs networks were integrated to create 3D nanostructured PANI/CNTs composites. Owing to their unique microstructure and conductivity, the PANI/CNTs nanocomposite exhibited excellent electrical properties such as remarkable supercapacitor performance and catalytic activity toward nitrite electrochemical reduction. It was found that the PANI/CNTs nanocomposite was capable of delivering high specific capacitance and showed excellent cycling stability. Moreover, it could be utilized as an electrochemical sensor for the detection of nitrite, with an outstanding sensitivity, low detection limit (6.1 μM, a signal to noise ratio of 3) and a fast response time of less than 5 s. [ABSTRACT FROM AUTHOR]

A facile two-step electrochemical strategy was reported to synthesize nanocomposite of reduced graphene oxide (RGO) doped conducting polymer poly (3,4-ethylenedioxythiophene) (PEDOT) decorated with nickel nanoparticles (NiNPs) onto a glassy carbon electrode (GCE). Pure graphene oxide (GO) doped PEDOT composite was firstly electropolymerized onto the GCE through cyclic voltammetry, followed by electrochemical reduction in a solution containing nickel cations at a constant potential of −0.9 V. During the electrochemical reduction process, GO doped in the PEDOT composite would be reduced to a more conductive form of RGO, and at the same time, nickel cations could be reduced to form NiNPs and loaded on the composite surface. The prepared nanocomposite (NiNPs/PEDOT/RGO) modified electrode showed outstanding electrocatalytic activity toward the oxidation of glucose in alkaline media, and it could be developed into a nonenzymatic glucose sensor. Under optimum conditions, the glucose sensor exhibited a linear range from 1.0 μM to 5.1 mM and a detection limit of 0.8 μM (S/N = 3), associated with excellent stability, high reproducibility and favorable selectivity against common interferents. Furthermore, the nonenzymatic sensor was also successfully applied to the detection of glucose in human serum samples, showing promising potential in the clinical application. [ABSTRACT FROM AUTHOR]

Graphite oxide was prepared by oxidizing graphite powder, reduced to graphene using hydrazine hydrate, and the grapheme was mixed with chitosan to form a composite that was used to modify a glassy carbon electrode for the determination of copper(II). The electrochemical behavior of the modified electrode was studied by cyclic and square wave voltammetries. The morphology and structure of the composite were characterized by infrared spectroscopy, transmission electron microscopy, and scanning electron microscopy. In addition, the proportion of composite material, pH, and adsorption time was optimized. Under the optimized experimental conditions, the sensor showed a linear dynamic range from 1.0 × 10−9to 1.5 × 10−8 mol · L−1for copper(II) with a limit of detection of 4.3 × 10−10 mol · L−1at a signal-to-noise ratio of three. The sensor displayed excellent electrochemical response and high sensitivity. [ABSTRACT FROM AUTHOR]

Cation-exchange-based chemiluminescence amplification (CXCLAmp) was developed in this study. After amplification by rolling circle amplification (RCA), the proposed RCA–CXCLAmp strategy was used to detect miRNA sensitively. [ABSTRACT FROM AUTHOR]

Abstract: Tumor-associated carbohydrate antigens (TACAs) are often found on the surface of cancer cells. The determination of the carbohydrate components of glycoconjugates is challenging because of the chemical complexity of glycan chains. Through monitoring corresponding antibody, we can get a good solution for clinical diagnosis. Here breast tumor-associated carbohydrate antigens Tn were used as a model and a new photoelectrochemical biosensor for ultrasensitive detection of antibody against Tn was developed. To enhance the sensitivity, both graphene oxide and graphene were used during the construction of biosensor. Through the formation of immunocomplex and the insoluble biocatalytic precipitation (BCP) product, photocurrent intensity was decreased greatly and the antibody could be detected from 0.5 to 500pg/mL with a detection limit of 1.0×10−13 g/mL. At the same time, the developed biosensor showed acceptable selectivity and could be used in the complex matrix. Compared with the traditional glycoarray method, this PEC method is more sensitive (5 orders of magnitude), and thus provides another platform to monitor the immune response to carbohydrate epitopes at different stages during differentiation, metastasis, or treatment. [Copyright &y& Elsevier]

• Periodic amplification strategies of DNA mimicking enzymes were employed. • High sensitivity for microRNA detection in vitro. • Clear imaging of microRNA in living cells. • pH-regulated automatic drug delivery system. • The dual functions of photothermal therapy and chemotherapy are combined in one. A novel iridium oxide nanoparticles-based probe was developed for in vivo fluorescence imaging of microRNA and synergistic chem/photothermal treatments of tumor. The theranostic nanoprobe was constructed by functionizing iridium oxide nanoparticles with split DNAzyme precursor and chemotherapeutic agent doxorubicin. The split DNAzyme precursor was used for specifically recognizing the target microRNA in cancer cells and then releasing the preloaded fluorescence for detection through DNAzyme cleavage reaction. Because the fluorescence was enhanced by cycle amplification process, the nanoprobe exhibited high sensitivity in the cell-free test. Both in vitro and in vivo fluorescence imaging studies proved the specificity and feasibility of the nanoprobe in tumor imaging. In order to enhance the effectiveness of cancer cell therapy, synergistic chem/photothermal treatments were designed on the nanoprobe. Based on the photothermally controlled drug release and chemotherapeutic treatment of doxorubicin, and the photothermal effect of iridium oxide nanoparticles, the nanoprobe exhibited excellent synergy effect on cancer cell treatment under near-infrared irradiation. In particular, in vivo therapeutic studies proved a great inhibition of the tumor growth. Therefore, this work provided a promising theranostic nanoprobe for both tumor imaging and synergistic treatment of cancer cells. [ABSTRACT FROM AUTHOR]