Copper (II) sulfate charring for high sensitivity on-plate fluorescent detection of lipids and sterols: quantitative analyses of the composition of functional secretory vesicles

Inspired by the active site structure of natural horseradish peroxidase having iron as a pivotal element with coordinated histidine residues, we have developed histidine coated magnetic nanoparticles (His@MNPs) with relatively uniform and small sizes (less than 10 nm) through one-pot heat treatment. In comparison to pristine MNPs and other amino acid coated MNPs, His@MNPs exhibited a considerably enhanced peroxidase-imitating activity, approaching 10-fold higher in catalytic reactions. With the high activity, His@MNPs then were exploited to detect the important neurotransmitter acetylcholine. By coupling choline oxidase and acetylcholine esterase with His@MNPs as peroxidase mimics, target choline and acetylcholine were successfully detected via fluorescent mode with high specificity and sensitivity with the limits of detection down to 200 and 100 nM, respectively. The diagnostic capability of the method is demonstrated by analyzing acetylcholine in human blood serum. This study thus demonstrates the potential of utilizing His@MNPs as peroxidase-mimicking nanozymes for detecting important biological and clinical targets with high sensitivity and reliability.

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Abstract 4336: Interrogating the Human Myocardial Interstitium during Myocardial Arrest and Reperfusion: Dynamic Changes in Cytokines and Protease Activity

Circulation ◽

10.1161/circ.118.suppl_18.s_867-a ◽

2008 ◽

Vol 118 (suppl_18) ◽

Author(s):

Robert E Stroud ◽

Christine N Koval ◽

Isabelle Gengler ◽

Anne M Deschamps ◽

John S Ikonomidis ◽

...

Keyword(s):

Detection System ◽

Ischemia Reperfusion ◽

Dynamic Assessment ◽

High Sensitivity ◽

Fluorescent Detection ◽

Suspension Array ◽

Cytokine Analysis ◽

And Function ◽

Inflammatory Molecules ◽

Pulmonary Bypass

Background. Cytokines, such as the interleukins (IL1β, IL2, IL6) and tumor necrosis factor (TNF) can modulate myocardial structure and function with ischemia/reperfusion (I/R) but dynamic assessment of these biological molecules within the human myocardial interstitium with I/R has not been performed, and the inter-relationship to matrix metalloproteinases activity (MMPact) remains unexplored. Accordingly, a fluorogenic microdialysis method was used to simultaneously measure myocardial interstitial cytokine levels and MMPact in patients during and following I/R. Methods . MMPact was measured in patients (n=13) undergoing cardio-pulmonary bypass (CPB) at baseline, during myocardial arrest and CPB (on-CPB), and immediately following reperfusion and separation from CPB (post-CPB) by a validated in-line microdialysis fluorescent detection system. Myocardial interstitial fluid was subjected to cytokine analysis by high sensitivity multiplex suspension array. Results . Interstitial MMPact increased by over 30% post-CPB and was accompanied by a specific change in cytokine profiles (Figure ). The classical pro-inflammatory molecules such as TNF and IL6 were either not detectable or unchanged, whereas IL1β and IL2 which can be proinflammatory, were increased. Conclusions. These unique results demonstrated that a dynamic cytokine signature occurs within the human myocardial interstitium following I/R and is temporally related to heightened MMP activity. Direct interrogation of the human myocardial interstitium may provide a unique insight into critical signaling pathways which may evoke adverse structural and functional events following I/R.

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Ratiometric fluorescent detection of dipicolinic acid as an anthrax biomarker based on a high-nuclearity Yb18 nanoring

Dalton Transactions ◽

10.1039/d1dt01731d ◽

2021 ◽

Vol 50 (38) ◽

pp. 13528-13532

Author(s):

Yanan Ma ◽

Xiaoping Yang ◽

Wenxin Hao ◽

Ting Zhu ◽

Chengri Wang ◽

...

Keyword(s):

Dipicolinic Acid ◽

High Sensitivity ◽

Organic Ligands ◽

Fluorescent Detection ◽

Fluorescent Response ◽

Sensitivity And Selectivity

An 18-metal Yb(iii) nanoring that shows a ratiometric fluorescent response to 2,6-dipicolinic acid with high sensitivity and selectivity was synthesized from two types of polydentate organic ligands.

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Metal ion-modulated graphene-DNAzyme interactions: design of a nanoprobe for fluorescent detection of lead(ii) ions with high sensitivity, selectivity and tunable dynamic range

Chemical Communications ◽

10.1039/c1cc11486g ◽

2011 ◽

Vol 47 (22) ◽

pp. 6278 ◽

Cited By ~ 138

Author(s):

Yanqin Wen ◽

Cheng Peng ◽

Di Li ◽

Lin Zhuo ◽

Shijiang He ◽

...

Keyword(s):

Metal Ion ◽

Dynamic Range ◽

High Sensitivity ◽

Fluorescent Detection

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One-Dimensional Fluorescent Nanosized-Diamond Nanowires with Fluorescent Detection of Vitamin B12

NANO ◽

10.1142/s179329201950084x ◽

2019 ◽

Vol 14 (07) ◽

pp. 1950084 ◽

Cited By ~ 1

Author(s):

Jilong Wang ◽

Siheng Su ◽

Jingjing Qiu ◽

Shiren Wang

Keyword(s):

Electron Microscopy ◽

Photoelectron Spectroscopy ◽

High Sensitivity ◽

Anodic Aluminum Oxide Template ◽

Fluorescent Detection ◽

Dimensional Structure ◽

Fluorescent Properties ◽

One Dimensional ◽

Sensitivity And Selectivity ◽

The One

In this paper, a novel and facile method to achieve fluorescent nanosized-diamond based nanowire (NW) is reported. One-dimensional (1D) organic NW has received tremendous attention due to its superior chemical functionality and size-, shape-, and material-dependent properties. In addition, nanosized-diamond is comprehensively studied and investigated due to superior tunable fluorescent properties, cost-effectiveness, facile manufacturing and high biocompatibility. Through thermal treatment, sulfur-modified nanosized-diamond was fabricated by mixing oxidized nanosized-diamond and dibenzyl disulfide at 900∘C. Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and zeta potential were employed to characterize sulfur-modified nanosized-diamond. After that, porous anodic aluminum oxide template-assisted cathodic electrophoretic deposition method was used to achieve sulfur-modified nanosized-diamond NW. Scanning electron microscopy and transmission electron microscopy were applied to present the one-dimensional structure of the NWs. The optical properties of sulfur nanosized-diamond NW were characterized via ultraviolet-visible spectroscopy and photoluminescence spectroscopy. Finally, the as-synthesized sulfur-modified nanosized-diamond NW-based optical sensor was fabricated to detect vitamin B[Formula: see text] with high sensitivity and selectivity.

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Highly Sensitive and Selective Fluorescent Detection of Gossypol Based on BSA-Stabilized Copper Nanoclusters

Molecules ◽

10.3390/molecules24010095 ◽

2018 ◽

Vol 24 (1) ◽

pp. 95 ◽

Cited By ~ 6

Author(s):

Shuangjiao Xu ◽

Kehai Zhou ◽

Dan Fang ◽

Lei Ma

Keyword(s):

High Performance ◽

Signal To Noise Ratio ◽

High Sensitivity ◽

Hplc Method ◽

Fluorescent Detection ◽

Copper Nanoclusters ◽

Highly Sensitive ◽

The Us ◽

Fluorescence Quenching Mechanism ◽

First Time

In this paper, fluorescent copper nanoclusters (NCs) are used as a novel probe for the sensitive detection of gossypol for the first time. Based on a fluorescence quenching mechanism induced by interactions between bovine serum albumin (BSA) and gossypol, fluorescent BSA-Cu NCs were seen to exhibit a high sensitivity to gossypol in the range of 0.1–100 µM. The detection limit for gossypol is 25 nM at a signal-to-noise ratio of three, which is approximately 35 times lower than the acceptable limit (0.9 µM) defined by the US Food and Drug Administration for cottonseed products. Moreover, the proposed method for gossypol displays excellent selectivity over many common interfering species. We also demonstrate the application of the present method to the measurement of several real samples with satisfactory recoveries, and the results agree well with those obtained using the high-performance liquid chromatography (HPLC) method. The method based on Cu NCs offers the followings advantages: simplicity of design, facile preparation of nanomaterials, and low experimental cost.

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High-Performance Thin-Layer Chromatography with Densitometry for the Determination of Ciprofloxacin and Impurities in Drugs

Journal of AOAC International ◽

10.1093/jaoac/88.5.1530 ◽

2005 ◽

Vol 88 (5) ◽

pp. 1530-1536 ◽

Cited By ~ 16

Author(s):

Jan Krzek ◽

Urszula Hubicka ◽

Justyna Szczepańczyk

Keyword(s):

Thin Layer ◽

High Performance ◽

Limit Of Detection ◽

Degradation Products ◽

Pharmaceutical Preparations ◽

High Sensitivity ◽

Good Precision ◽

Relative Standard ◽

Tlc Plates ◽

Quantitative Analyses

Abstract A thin-layer chromatographic (TLC)-densitometric method has been developed for identification and quantification of ciprofloxacin (Rf = 0.61) and an ethylenediamine compound (Rf = 0.42), a desfluoro compound (Rf = 0.48), by-compound A (Rf = 0.53), and fluoroquinolonic acid (Rf = 0.68) as ciprofloxacin degradation products in pharmaceutical preparations. By using chloroform–methanol–25% ammonia (43 + 43 + 14, v/v/v) as the mobile phase and silica gel 60 F254 high-performance TLC plates as the stationary phase, it was possible to separate individual constituents that, when subjected to ultraviolet (UV) densitometric analysis at 330 nm for fluoroquinolonic acid and 277 nm for the other compounds, gave well developed peaks allowing easy qualitative and quantitative analyses. DMSO–methanol (1 + 1) was used to extract drug constituents. The method showed high sensitivity (limit of detection 10 to 44 ng), a wide linearity range (3 to 20 μg/mL), and good precision (2.32 to 6.46% relative standard deviation) and accuracy (percentage recoveries 98.62 to 101.52%) for individual constituents.

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Phosphorescent porphyrin probes in biosensors and sensitive bioassays

Biochemical Society Transactions ◽

10.1042/bst0280074 ◽

2000 ◽

Vol 28 (2) ◽

pp. 74-77 ◽

Cited By ~ 47

Author(s):

D. B. Papkovsky ◽

T. O'Riordan ◽

A. Soini

Keyword(s):

Oxygen Sensor ◽

Spectral Characteristics ◽

Screening Method ◽

High Sensitivity ◽

Water Soluble ◽

Fluorescent Detection ◽

Rapid Screening ◽

Time Resolved ◽

Phosphorescence Lifetime ◽

Practical Applications

Platinum(II) and palladium(II) complexes of porphyrins and related tetrapyrrolic pigments emit strong phosphorescence at room temperatures, which is characterized by long lifetimes falling into the sub-millisecond range and long-wave spectral characteristics. These features make the dyes useful as probes for a number of bioanalytical applications, particularly those employing time-resolved fluorescent detection. They can provide high sensitivity and selectivity, together with rather simple instrumental set-up. A number of analytical systems are now under development that are based on the use of phosphorescent porphyrin probes. Experimental results are presented on the following systems: (i) fibre-optic phosphorescence lifetime-based oxygen sensor on the basis of hydrophobic platinum-porphyrins and development of advanced sensing materials and prototype instrumentation; (ii) practical applications of the optical oxygen sensor, including a sensitive immunosensor that employs glucose oxidase labels, a rapid screening method for cell viability in microtitre-plate format, non-destructive measurement of oxygen in packaged foods and reagentless biosensors for metabolites (glucose, lactate); and (iii) the use of water-soluble platinum- and palladium-porphyrins as labels for ultra-sensitive time-resolved phosphorescence immunoassays.

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