Colorimetric sensor array for sensitive detection and identification of bacteria based on the etching of triangular silver nanoparticles regulated by Cl at various concentrations.

A colorimetric sensor array is proposed for ultrasensitive detection and identification of bacteria by using Cl at various concentrations as sensing elements and triangular silver nanoparticles (T-AgNPs) as a single sensing nanoprobe. T-AgNPs are easily etched by Cl. However, in the presence of bacteria, the etching process will be hindered.

Influence of dissolved organic matter and heavy metals on the utilization of soil-like material mined from different types of MSW landfills.

Soil-like material (SLM) mined from municipal solid waste (MSW) landfills can be used as nursery cultivation soil, landfill cover, and as a building material. However, SLM utilization is restrained by heavy metal (HM) contents whose speciation and migration are influenced by their dissolved organic matter (DOM) content. Therefore, the properties of aged refuse and the correlation between DOM and HM forms were studied using samples from different types of MSW landfills.

Development of pH-responsive nanocomposites with remarkably synergistic antibiofilm activities based on ultrasmall silver nanoparticles in combination with aminoglycoside antibiotics.

Bacterial biofilms are responsible for many chronic infections because antibacterial agents exhibit poor penetration into the dense matrix barrier and cannot easily reach the internal bacteria. Herein, we reported pH-responsive nanocomposites (PDA@Kana-AgNPs) that could penetrate and disperse biofilms, which were synthesized by the combination of ultrasmall silver nanoparticles (AgNPs) and kanamycin, and then coating with polydopamine. Confocal fluorescence imaging indicated that PDA@Kana-AgNPs could respond to the acidic microenvironment of biofilms, leading to biofilm-triggered on- demand drug release in situ.

Array-based microbial identification upon extracellular aminoglycoside residue sensing.

Sensitive and rapid identification of pathogenic microorganisms is of great importance for clinical diagnosis and treatment. In this study, we developed an ultrasensitive colorimetric sensor array (CSA) based on the interactions between aminoglycoside antibiotics (AMGs) and Ag nanoparticles decorated with β-cyclodextrin (AgNPs@β-CD) to discriminate microorganisms quickly and accurately. Microorganisms can absorb different amounts of AMGs after incubation.

Construction of Biocompatible Dual-Drug Loaded Complicated Nanoparticles for Improvement of Synergistic Chemotherapy in Esophageal Cancer.

Combination chemotherapy is a routine treatment for esophageal cancer, but some shortcomings, such as drug toxicity and side effects, greatly limit the clinical application of combination therapy. To overcome these shortcomings, we have developed a mesoporous silica nanoparticle system that was used to load doxorubicin and β-elemene. β-elemene was encapsulated in the pore of mesoporous silica nanoparticle and doxorubicin was electrostatically adsorbed on the surface of mesoporous silica nanoparticle by hyaluronic acid to construct dual drugs synergistic nanoparticles (bMED NPs, ~77.

GMBP1-conjugated manganese oxide nanoplates for monitoring of gastric cancer MDR using magnetic resonance imaging.

Multidrug resistance (MDR) is a huge challenge for gastric cancer chemotherapy. Therefore, MDR accurate monitoring is of great significance for the treatment of gastric cancer. GMBP1, an extracellular internalization peptide, can target MDR gastric cancer cells through specific binding to GRP78, which is an MDR-related protein that is overexpressed in gastric cancer cells.

Colorimetric Sensor Array Based on Wulff-Type Boronate Functionalized AgNPs at Various pH for Bacteria Identification.

The efficient identification of bacteria is of considerable significance in clinical diagnosis. Herein, a novel colorimetric sensor array was developed for the detection and identification of bacteria based on the specific affinity and electrostatic interaction between Wulff-type 4-mercaptophenylboronic acid (MPBA)-mercaptoethylamine (MA) cofunctionalized AgNPs (MPBA-MA@AgNPs) and bacteria at various pH. In the neutral and alkaline conditions, AgNPs tended to be dispersed due to the specific affinity between -diol residues contained in carbohydrate-rich compositions on the bacterial cell surface and MPBA.

Riboflavin-protected ultrasmall silver nanoclusters with enhanced antibacterial activity and the mechanisms.

Developing silver nanomaterials with efficient antimicrobial properties is of importance for combating bacteria. Here, we report ultrasmall riboflavin-protected silver nanoclusters (RF@AgNCs) that can effectively kill or suppress the growth of Gram-positive , Gram-negative , and fungi . Riboflavin (RF) with intrinsic biocompatibility was used as a surface ligand to synthesize silver nanoclusters.

A pH-based sensor array for the detection and identification of proteins using CdSe/ZnS quantum dots as an indicator.

Protein identification is very important in the field of clinical medicine and diagnosis. Here, we report a novel and simple sensor array for the detection and identification of proteins using pH buffer solutions as sensing elements. Different proteins in various pH solutions have different net surface charges including positive, negative or no charge.

Colorimetric Sensor Array Based on Gold Nanoparticles with Diverse Surface Charges for Microorganisms Identification.

We report a simple and novel colorimetric sensor array for rapid identification of microorganisms. In this study, four gold nanoparticles (AuNPs) with diverse surface charges were used as sensing elements. The interactions between AuNPs and microorganisms led to obvious color shifts, which could be observed by the naked eye.

Colorimetric sensor array with unmodified noble metal nanoparticles for naked-eye detection of proteins and bacteria.

Herein we report a novel strategy for the detection and identification of proteins using unmodified noble metal nanoparticles. Five gold nanoparticles (AuNPs) and two silver nanoparticles (AgNPs) with different sizes were utilized as sensing elements to create a colorimetric sensor array. In the presence of proteins, the UV-vis absorbance of the noble metal nanoparticles changed due to the interactions between the protein and nanoparticles, producing distinct absorbance response patterns which can be visually detected by the naked eye.

Highly sensitive fluorescence assay of DNA methyltransferase activity via methylation-sensitive cleavage coupled with nicking enzyme-assisted signal amplification.

Herein, using DNA adenine methylation (Dam) methyltransferase (MTase) as a model analyte, a simple, rapid, and highly sensitive fluorescence sensing platform for monitoring the activity and inhibition of DNA MTase was developed on the basis of methylation-sensitive cleavage and nicking enzyme-assisted signal amplification. In the presence of Dam MTase, an elaborately designed hairpin probe was methylated. With the help of methylation-sensitive restriction endonuclease DpnI, the methylated hairpin probe could be cleaved to release a single-stranded DNA (ssDNA).

Amplified fluorescence detection of mercury(II) ions (Hg2+) using target-induced DNAzyme cascade with catalytic and molecular beacons.

In this work, a fluorescent sensing strategy was developed for the detection of mercury(II) ions (Hg(2+)) in aqueous solution with excellent sensitivity and selectivity using a target-induced DNAzyme cascade with catalytic and molecular beacons (CAMB). In order to construct the biosensor, a Mg(2+)-dependent DNAzyme was elaborately designed and artificially split into two separate oligonucleotide fragments. In the presence of Hg(2+), the specific thymine-Hg(2+)-thymine (T-Hg(2+)-T) interaction induced the two fragments to produce the activated Mg(2+)-dependent DNAzyme, which would hybridize with a hairpin-structured MB substrate to form the CAMB system.

Ultrasensitive and selective detection of nicotinamide adenine dinucleotide by target-triggered ligation-rolling circle amplification.

An ultrasensitive fluorescence assay for nicotinamide adenine dinucleotide (NAD(+)) was developed by target-triggered ligation-rolling circle amplification (L-RCA). This novel approach can detect as low as 1 pM NAD(+), much lower than those of previously reported biosensors, and exhibits high discrimination ability even against 200 times excess of NAD(+) analogs.

Analysis of 2-propanol in exhaled breath using in situ enrichment and cataluminescence detection.

We report a simple gaseous sensor for the sensitive detection of trace 2-propanol in exhaled breath using in situ enrichment and cataluminescence detection method on the surface of nanomaterials. The influences of heating voltage and absorption time on the CTL intensity were discussed, respectively. In the selected conditions, the linear range of 2-propanol concentration is 60-600 ppbv and the detection of limit is 11 ppbv.

Dual-channel sensing of volatile organic compounds with semiconducting nanoparticles.

Extracting multidimensional information from an individual transducer simultaneously is a promising alternative sensing strategy to traditional sensors. Here, we proposed a novel dual channel sensing method with simultaneously recording conductivity change of sensing material and chemiluminescence emission during catalytic oxidation of volatile organic compounds on tin oxide nanoparticles. The orthogonal and complementary electrical and optical signals have been obtained for each compound, which have been applied to discriminate 20 volatile organic compounds using hierarchical cluster analysis (HCA).

Discrimination and identification of flavors with catalytic nanomaterial-based optical chemosensor array.

A cross-reactive chemiluminescence (CL) sensor array based on catalytic nanomaterials was constructed for the discrimination and identification of flavors in cigarettes. A total of 21 nanomaterials, including metal oxides, metal oxides deposited on carbon nanotubes (CNTs), gold nanoparticles deposited on metal oxides, and carbonate, have been carefully selected as sensing elements of the array. Each flavor gives its unique CL pattern from the array, which is able to be employed for the discrimination and identification of flavors.

Development of a benzaldehyde sensor utilizing chemiluminescence on nanosized Y2O3.

A chemiluminescence sensor has been proposed for sensitive determination of benzaldehyde, with nanosized Y(2)O(3) as the sensing material. Under optimized conditions, the linear range of the CL intensity vs. the concentration of benzaldehyde vapour is 1.

On-line concentration and determination of all-trans- and 13-cis- retinoic acids in rabbit serum by application of sweeping technique in micellar electrokinetic chromatography.

A simple and rapid micellar electrokinetic chromatography (MEKC) method with UV detection was developed for the simultaneous separation and determination of all-trans- and 13-cis-retinoic acids in rabbit serum by on-line sweeping concentration technique. The serum sample was simply deproteinized and centrifuged. Various parameters affecting sample enrichment and separation were systematically investigated.

Separation and determination of bupivacaine in plasma by capillary electrophoresis with tris(2,2'-bipyridyl)ruthenium(II) electrochemiluminescence detection.

A new, rapid, selective and sensitive method is described for determination of bupivacaine by capillary electrophoresis coupled with tris(2,2'-bipyridyl)ruthenium(II) [Ru(bpy)(3)2+] electrochemiluminescence detection. The influence of parameters such as detection potential, Ru(bpy)(3)2+ concentration, buffer concentration and pH, injection time and separation voltage on separation efficiency and ECL peak intensity was systematically investigated. Under optimized conditions, the calibration curve was linear in the range 0.

A rapid capillary electrophoresis with electrochemiluminescence method for the assay of human urinary proline and hydroxyproline.

A novel simultaneous determination method for free and total proline (Pro) and hydroxyproline (Hyp) in human urine was developed, based on capillary electrophoresis (CE) with electrochemiluminescence (ECL) detection, using tris-(2,2'-bipyridyl) ruthenium(II). Experimental conditions, such as the Ru(bpy)(3)2+ concentration, detection potentials, buffer concentration and pH in CE or in the ECL cell, injection voltage and time were investigated in detail. Under optimized conditions, the linear range, detection limit and sample recoveries for the method were 0.