A novel sensor for sequential and cellular detection of copper and lactic acid

<div> We report self assembling/aggregation properties of acyl-thiourea derivative, N-((6-methoxy-pyridin-2-yl)carbamothioyl)benzamide<a>(NG1) </a><a>[i1]</a> and the disaggregation induced emission which leads to its application as fluorescence and colorimetric probe for the sensitive detection of Cu2+. The microscopy analysis of NG1via SEM, and AFM reveal that it self-assembles to give fiber-like morphologies.Interestingly,NG1 also assembles to fluorescent fibers which show tunable emission properties. Addition of Cu2+to these fibers causedisruption/disaggregation of fibers and a golden yellow fluorescence is produced due to disaggregation induced emission enhancement (DIEE). The application of NG1 as selective sensor for copper was further assessed by UV visible and fluorescence spectroscopy. Limit of Detection(LOD) of Cu2+ with colorimetry was 2.5ppm while LOD of Cu2+ with fluorescence was as low as 0.1ppm. This yellow fluorescence is quenched after the addition of lactic acid and hence NG1 could potentially be used for the sequential detection of both Cu and lactate.Further, structural modification of the probe NG1 suggest crucial role of both pyridine and acyl-thiourea moiety in the binding of Cu2+. The experimental results of interaction of NG1 with Cu2+ and lactate were also validated theoretically by quantum chemical calculations based on density functional theory (DFT). Finally, we explore the ability of NG1for the sequential detection of Cu2+ and lactate in cells, which suggestsNG1 can be used effectively for the cellular imaging applications and to selectively sense Cu2+. To, the best of our knowledge,</div> this is the first report wherein a dual sensor for Cu2+and lactate ion is synthesized and it may in allpossibilities pave the way for the diagnosis of Cu2+associated disorders like Wilson’s disease and in the detection of elevated lactate levels which are associated with the wide range of pathologies likemitochondrial diseases, cerebral ischemia and cancer. <div> </div>

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A new disaggregation induced emission enhancement (DIEE)based probe for cellular detection of copper and lactate

10.26434/chemrxiv.8003507.v3 ◽

2019 ◽

Author(s):

Nidhi Gour ◽

chandra kanth P ◽

Sumit Kharbanda ◽

Deepak Kumar Pandey ◽

Manoj kumar pandey ◽

...

Keyword(s):

Density Functional ◽

Limit Of Detection ◽

Sequential Detection ◽

Yellow Fluorescence ◽

Self Assembling ◽

Emission Enhancement ◽

Golden Yellow ◽

Wide Range ◽

Dual Sensor ◽

Lactate Levels

<div> We report self assembling/aggregation properties of acyl-thiourea derivative, N-((6-methoxy-pyridin-2-yl)carbamothioyl)benzamide<a>(NG1) </a><a>[i1]</a> and the disaggregation induced emission which leads to its application as fluorescence and colorimetric probe for the sensitive detection of Cu2+. The microscopy analysis of NG1via SEM, and AFM reveal that it self-assembles to give fiber-like morphologies.Interestingly,NG1 also assembles to fluorescent fibers which show tunable emission properties. Addition of Cu2+to these fibers causedisruption/disaggregation of fibers and a golden yellow fluorescence is produced due to disaggregation induced emission enhancement (DIEE). The application of NG1 as selective sensor for copper was further assessed by UV visible and fluorescence spectroscopy. Limit of Detection(LOD) of Cu2+ with colorimetry was 2.5ppm while LOD of Cu2+ with fluorescence was as low as 0.1ppm. This yellow fluorescence is quenched after the addition of lactic acid and hence NG1 could potentially be used for the sequential detection of both Cu and lactate.Further, structural modification of the probe NG1 suggest crucial role of both pyridine and acyl-thiourea moiety in the binding of Cu2+. The experimental results of interaction of NG1 with Cu2+ and lactate were also validated theoretically by quantum chemical calculations based on density functional theory (DFT). Finally, we explore the ability of NG1for the sequential detection of Cu2+ and lactate in cells, which suggestsNG1 can be used effectively for the cellular imaging applications and to selectively sense Cu2+. To, the best of our knowledge,</div> this is the first report wherein a dual sensor for Cu2+and lactate ion is synthesized and it may in allpossibilities pave the way for the diagnosis of Cu2+associated disorders like Wilson’s disease and in the detection of elevated lactate levels which are associated with the wide range of pathologies likemitochondrial diseases, cerebral ischemia and cancer. <div> </div>

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A new disaggregation induced emission enhancement (DIEE)based probe for cellular detection of copper and lactate

10.26434/chemrxiv.8003507.v2 ◽

2019 ◽

Author(s):

Nidhi Gour ◽

Vivek Shinh Kshtriya ◽

Dheeraj K Singh ◽

chandra kanth P ◽

Dhiraj Bhatia

Keyword(s):

Density Functional ◽

Limit Of Detection ◽

Sequential Detection ◽

Yellow Fluorescence ◽

Self Assembling ◽

Emission Enhancement ◽

Golden Yellow ◽

Wide Range ◽

Dual Sensor ◽

Lactate Levels

<div> We report self assembling/aggregation properties of acyl-thiourea derivative, N-((6-methoxy-pyridin-2-yl)carbamothioyl)benzamide<a>(NG1) </a><a>[i1]</a> and the disaggregation induced emission which leads to its application as fluorescence and colorimetric probe for the sensitive detection of Cu2+. The microscopy analysis of NG1via SEM, and AFM reveal that it self-assembles to give fiber-like morphologies.Interestingly,NG1 also assembles to fluorescent fibers which show tunable emission properties. Addition of Cu2+to these fibers causedisruption/disaggregation of fibers and a golden yellow fluorescence is produced due to disaggregation induced emission enhancement (DIEE). The application of NG1 as selective sensor for copper was further assessed by UV visible and fluorescence spectroscopy. Limit of Detection(LOD) of Cu2+ with colorimetry was 2.5ppm while LOD of Cu2+ with fluorescence was as low as 0.1ppm. This yellow fluorescence is quenched after the addition of lactic acid and hence NG1 could potentially be used for the sequential detection of both Cu and lactate.Further, structural modification of the probe NG1 suggest crucial role of both pyridine and acyl-thiourea moiety in the binding of Cu2+. The experimental results of interaction of NG1 with Cu2+ and lactate were also validated theoretically by quantum chemical calculations based on density functional theory (DFT). Finally, we explore the ability of NG1for the sequential detection of Cu2+ and lactate in cells, which suggestsNG1 can be used effectively for the cellular imaging applications and to selectively sense Cu2+. To, the best of our knowledge,</div> this is the first report wherein a dual sensor for Cu2+and lactate ion is synthesized and it may in allpossibilities pave the way for the diagnosis of Cu2+associated disorders like Wilson’s disease and in the detection of elevated lactate levels which are associated with the wide range of pathologies likemitochondrial diseases, cerebral ischemia and cancer. <div> </div>

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A Dual Sensor Probe for the Sequential Detection of Copper(II) and Lactic Acid

10.26434/chemrxiv.8003507.v1 ◽

2019 ◽

Author(s):

Vivek Shinh Kshtriya ◽

Bharti Koshti ◽

chandra kanth P ◽

Manoj kumar pandey ◽

Nidhi Gour

Keyword(s):

Lactic Acid ◽

Crucial Role ◽

Mitochondrial Diseases ◽

Sequential Detection ◽

Yellow Fluorescence ◽

Yellow Solution ◽

Wide Range ◽

Dual Sensor ◽

Dual Detection ◽

Lactate Levels

Herein, we report a novel fluorescent probe for the sequential detection of Copper II (Cu2+) and lactic acid. The probe based on acyl-thiourea derivative, N-((6-methoxypyridin-2-yl)carbamothioyl)benzamide (1) was synthesized, and its application as dual sensor for Cu2+ and lactic acid is reported. The dual detection by the probe is possible since 1 formed complex with Cu2+ and yielded yellow solution which disappeared after the addition of lactic acid. The probe exhibits yellow fluorescence with Cu2+ and LOD of Cu2+ with fluorescence is as low as 0.1ppm. The fluorescence is quenched after the addition of lactic acid and LOD of fluorescence quenching by lactate is as low as 1 ppm. Further, structural modification in the probe 1 suggest crucial role of both pyridine and acyl-thiourea moiety in the binding of Cu2+. Interestingly, 1 also assembles to fluorescent fibers which show tunable emission properties. These fibers are broken in the presence of Cu2+ and regenerated in the presence of lactic acid. Hence, disaggregation at molecular level might play a crucial role in causing yellow fluorescence in the presence of Cu2+. To, the best of our knowledge, this is the first report wherein a dual sensor for Cu2+ and lactate ion is synthesized and it may in all possibilities pave the way for diagnosis of Cu2+ associated disorders like Wilson’s disease and in the detection of elevated lactate levels which are associated with wide range of pathologies like mitochondrial diseases, cerebral ischemia and cancer.

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Rhodamine-Sulphuric Acid -A New Visualization Reagent for the Determination of Sucralose by HPTLC

E-Journal of Chemistry ◽

10.1155/2010/264369 ◽

2010 ◽

Vol 7 (s1) ◽

pp. S559-S565 ◽

Cited By ~ 3

Author(s):

Mohd Idris ◽

Seema Srivastava ◽

T. R. Baggi ◽

S. K. Shulka ◽

A. K. Ganjoo

Keyword(s):

Sulphuric Acid ◽

Limit Of Detection ◽

Solvent System ◽

Artificial Sweetener ◽

Yellow Fluorescence ◽

Relative Standard ◽

Golden Yellow ◽

Solvent Systems ◽

Olive Green

Sucralose a UV-visible inactive compound was separated on silica gel plate without any plate treatment prior to analysis, derivatized with rhodamine - sulphuric acid reagent and detected densitometrically at 456 nm as olive green band. With this reagent sucralose also shows golden yellow fluorescence at 366 nm. Two new solvent systemsi.e. chloroform: methanol: toluene (v/v 5:3.5:1.5) (solvent system-I) and chloroform: ethanol: benzene (v/v 5:3:2) (solvent system-II) were developed and giving Rfvalues of 0.62 and 0.45 respectively. The method was found to be sensitive with good limit of detection (LOD) for two solvent systems. The method imparts specificity to the method as at 456 nm sucralose only gives olive green color spots where as other artificial sweeteners did not show any response to this reagent, where as carbohydrates gives black color spots. Similarly sucralose gives golden yellow fluorescence at 366 nm which is not given by any other artificial sweetener. The method was highly reproducible with relative standard deviation (RSD)≤3% (n=3) and was applied for the determination of sucralose in different matrices like cola drinks, lemon juices, sugar free sweets, tabletop sweeteners etc.etc.

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Factors Affecting Molecular Self-Assembly and Its Mechanism

Scientific Research Journal ◽

10.24191/srj.v9i1.5385 ◽

2012 ◽

Vol 9 (1) ◽

pp. 43 ◽

Cited By ~ 1

Author(s):

Hueyling Tan

Keyword(s):

Self Assembly ◽

Building Blocks ◽

Molecular Engineering ◽

Molecular Structures ◽

Polymer Science ◽

New Approach ◽

Factors Affecting ◽

Dna Structures ◽

Self Assembling ◽

Wide Range

Molecular self-assembly is ubiquitous in nature and has emerged as a new approach to produce new materials in chemistry, engineering, nanotechnology, polymer science and materials. Molecular self-assembly has been attracting increasing interest from the scientific community in recent years due to its importance in understanding biology and a variety of diseases at the molecular level. In the last few years, considerable advances have been made in the use ofpeptides as building blocks to produce biological materials for wide range of applications, including fabricating novel supra-molecular structures and scaffolding for tissue repair. The study ofbiological self-assembly systems represents a significant advancement in molecular engineering and is a rapidly growing scientific and engineering field that crosses the boundaries ofexisting disciplines. Many self-assembling systems are rangefrom bi- andtri-block copolymers to DNA structures as well as simple and complex proteins andpeptides. The ultimate goal is to harness molecular self-assembly such that design andcontrol ofbottom-up processes is achieved thereby enabling exploitation of structures developed at the meso- and macro-scopic scale for the purposes oflife and non-life science applications. Such aspirations can be achievedthrough understanding thefundamental principles behind the selforganisation and self-synthesis processes exhibited by biological systems.

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Intrinsic Stacking Interactions of Natural and Artificial Nucleobases

10.26434/chemrxiv.11400405 ◽

2019 ◽

Author(s):

Drew P. Harding ◽

Laura J. Kingsley ◽

Glen Spraggon ◽

Steven Wheeler

Keyword(s):

Gas Phase ◽

Electrostatic Interactions ◽

Density Functional ◽

Molecular Descriptors ◽

Stacking Interactions ◽

Interaction Energies ◽

Functional Theory ◽

Binding Partner ◽

Heavy Atoms ◽

Wide Range

The intrinsic (gas-phase) stacking energies of natural and artificial nucleobases were explored using density functional theory (DFT) and correlated ab initio methods. Ranking the stacking strength of natural nucleobase dimers revealed a preference in binding partner similar to that seen from experiments, namely G > C > A > T > U. Decomposition of these interaction energies using symmetry-adapted perturbation theory (SAPT) showed that these dispersion dominated interactions are modulated by electrostatics. Artificial nucleobases showed a similar stacking preference for natural nucleobases and were also modulated by electrostatic interactions. A robust predictive multivariate model was developed that quantitively predicts the maximum stacking interaction between natural and a wide range of artificial nucleobases using molecular descriptors based on computed electrostatic potentials (ESPs) and the number of heavy atoms. This model should find utility in designing artificial nucleobase analogs that exhibit stacking interactions comparable to those of natural nucleobases. Further analysis of the descriptors in this model unveil the origin of superior stacking abilities of certain nucleobases, including cytosine and guanine.

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Efficient Prediction of Structural and Electronic Properties of Hybrid 2D Materials Using DFT and Machine Learning

10.26434/chemrxiv.6254756.v1 ◽

2018 ◽

Author(s):

Sherif Tawfik ◽

Olexandr Isayev ◽

Catherine Stampfl ◽

Joseph Shapter ◽

David Winkler ◽

...

Keyword(s):

Machine Learning ◽

Band Gap ◽

Density Functional ◽

2D Materials ◽

Van Der Waals ◽

Building Blocks ◽

Machine Learning Techniques ◽

Interlayer Distance ◽

Computational Screening ◽

Wide Range

Materials constructed from different van der Waals two-dimensional (2D) heterostructures offer a wide range of benefits, but these systems have been little studied because of their experimental and computational complextiy, and because of the very large number of possible combinations of 2D building blocks. The simulation of the interface between two different 2D materials is computationally challenging due to the lattice mismatch problem, which sometimes necessitates the creation of very large simulation cells for performing density-functional theory (DFT) calculations. Here we use a combination of DFT, linear regression and machine learning techniques in order to rapidly determine the interlayer distance between two different 2D heterostructures that are stacked in a bilayer heterostructure, as well as the band gap of the bilayer. Our work provides an excellent proof of concept by quickly and accurately predicting a structural property (the interlayer distance) and an electronic property (the band gap) for a large number of hybrid 2D materials. This work paves the way for rapid computational screening of the vast parameter space of van der Waals heterostructures to identify new hybrid materials with useful and interesting properties.

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Ab initio calculation on the Optical Properties of AA- Stacked two dimensional Graphene, Silicene, Germanene, and Stanene

International Journal of Computational Physics Series ◽

10.29167/a1i1p46-50 ◽

2018 ◽

Vol 1 (1) ◽

pp. 46-50

Author(s):

Rita John ◽

Benita Merlin

Keyword(s):

Optical Properties ◽

Band Structure ◽

Density Functional ◽

Electronic Band Structure ◽

Complex Refractive Index ◽

Single Layer ◽

Generalized Gradient ◽

Electronic Band ◽

Wide Range ◽

Optical Region

In this study, we have analyzed the electronic band structure and optical properties of AA-stacked bilayer graphene and its 2D analogues and compared the results with single layers. The calculations have been done using Density Functional Theory with Generalized Gradient Approximation as exchange correlation potential as in CASTEP. The study on electronic band structure shows the splitting of valence and conduction bands. A band gap of 0.342eV in graphene and an infinitesimally small gap in other 2D materials are generated. Similar to a single layer, AA-stacked bilayer materials also exhibit excellent optical properties throughout the optical region from infrared to ultraviolet. Optical properties are studied along both parallel (||) and perpendicular ( ) polarization directions. The complex dielectric function (ε) and the complex refractive index (N) are calculated. The calculated values of ε and N enable us to analyze optical absorption, reflectivity, conductivity, and the electron loss function. Inferences from the study of optical properties are presented. In general the optical properties are found to be enhanced compared to its corresponding single layer. The further study brings out greater inferences towards their direct application in the optical industry through a wide range of the optical spectrum.

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Validated Stability Indicating HPTLC Method for the Estimation of Amoxapine in Different Stress Conditions

Current Pharmaceutical Analysis ◽

10.2174/1573412914666171228163122 ◽

2019 ◽

Vol 15 (3) ◽

pp. 273-279

Author(s):

Shweta G. Rangari ◽

Nishikant A. Raut ◽

Pradip W. Dhore

Keyword(s):

High Performance ◽

Limit Of Detection ◽

Degradation Products ◽

Analysis Data ◽

Peak Height ◽

Good Resolution ◽

Stability Indicating ◽

Limit Of Quantitation ◽

Wide Range ◽

Hptlc Method

Background:The unstable and/or toxic degradation products may form due to degradation of drug which results into loss of therapeutic activity and lead to life threatening condition. Hence, it is important to establish the stability characteristics of drug in various conditions such as in temperature, light, oxidising agent and susceptibility across a wide range of pH values.Introduction:The aim of the proposed study was to develop simple, sensitive and economic stability indicating high performance thin layer chromatography (HPTLC) method for the quantification of Amoxapine in the presence of degradation products.Methods:Amoxapine and its degraded products were separated on precoated silica gel 60F254 TLC plates by using mobile phase comprising of methanol: toluene: ammonium acetate (6:3:1, v/v/v). The densitometric evaluation was carried out at 320 nm in reflectance/absorbance mode. The degradation products obtained as per ICH guidelines under acidic, basic and oxidative conditions have different Rf values 0.12, 0.26 and 0.6 indicating good resolution from each other and pure drug with Rf: 0.47. Amoxapine was found to be stable under neutral, thermal and photo conditions.Results:The method was validated as per ICH Q2 (R1) guidelines in terms of accuracy, precision, ruggedness, robustness and linearity. A good linear relationship between concentration and response (peak area and peak height) over the range of 80 ng/spot to 720 ng/spot was observed from regression analysis data showing correlation coefficient 0.991 and 0.994 for area and height, respectively. The limit of detection (LOD) and limit of quantitation (LOQ) for area were found to be 1.176 ng/mL and 3.565 ng/mL, whereas for height, 50.063 ng/mL and 151.707 ng/mL respectively.Conclusion:The statistical analysis confirmed the accuracy, precision and selectivity of the proposed method which can be effectively used for the analysis of amoxapine in the presence of degradation products.

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