Sensitive and selective determination of peptides, PG and PGP, using a novel fluorogenic reagent 4-chlorobenzene-1,2-diol

2015 ◽  
Vol 69 (4) ◽  
Author(s):  
Hasina Yasmin ◽  
Mohammed Shafikur Rahman ◽  
Takayuki Shibata ◽  
Tsutomu Kabashima ◽  
Masaaki Kai
Keyword(s):  
Reaction Time ◽  
Linear Relationship ◽  
Fluorescence Intensity ◽  
Sodium Periodate ◽  
Selective Detection ◽  
Fluorometric Method ◽  
Reaction Conditions ◽  
Fluorescent Signal ◽  
Selective Determination

AbstractA novel fluorometric method was developed for the sensitive and selective detection of Pro-Gly (PG) and Pro-Gly-Pro (PGP) using 4-chlorobenzene-1,2-diol (4-CBD) as a fluorogenic reagent. The reaction was performed at 37°C for 30 min in the presence of a borate buffer (pH 7.0) and sodium periodate. The resulting fluorescence intensity was measured using a spectrofluorometer with excitation and emission wavelengths of 450 nm and 535 nm. To obtain a stable fluorescent signal and maximise its intensity, different reaction conditions such as the concentrations of the reagents, the reaction time, and the pH were optimised. Under the optimised conditions, a linear relationship was obtained between fluorescence intensity and peptide concentrations from 1.0-40.0 μmol L

A Novel Fluorescent Nanoswitch Based on Carbon Dots for Sensitive Detection of Hg2+ and I−

NANO ◽  
2017 ◽  
Vol 12 (02) ◽  
pp. 1750024 ◽  
Author(s):  
Xiqing Liu ◽  
Xiao Wei ◽  
Yeqing Xu ◽  
Hongji Li ◽  
Kai Lu ◽  
...  
Keyword(s):  
Linear Relationship ◽  
Fluorescence Intensity ◽  
Carbon Dots ◽  
Limit Of Detection ◽  
Hydrothermal Process ◽  
Fluorescence Emission ◽  
Selective Determination ◽  
Fluorescence Switching ◽  
Interfering Ions

In this paper, a novel fluorescent nanoswitch based on carbon dots (CDs) was developed for the sensitive and selective determination of Hg[Formula: see text] and I[Formula: see text]. The CDs were obtained by simple hydrothermal process and had a strong fluorescence emission at 440[Formula: see text]nm. The fluorescence of the CDs can be selectively quenched by Hg[Formula: see text] ion, and then the I[Formula: see text] was added into the system, which can interact with Hg[Formula: see text] and recover fluorescence of the CDs. Under optimal conditions, the quenching fluorescence intensity on addition of Hg[Formula: see text] has obtained a satisfactory linear relationship covering the linear range of 0–50[Formula: see text][Formula: see text]M with the linear relationship ([Formula: see text]), and the limit of detection is 0.047[Formula: see text][Formula: see text]M. The additions of I[Formula: see text] could lead to the fluorescence intensity of the solution of CDs and Hg[Formula: see text] (50[Formula: see text][Formula: see text]M) recover rapidly, which is linearly related ([Formula: see text]) to the concentration of I[Formula: see text] in the range from 0 to 70[Formula: see text][Formula: see text]M, the detection limit for I[Formula: see text] was calculated to be 0.084[Formula: see text][Formula: see text]M. Moreover, the developed method to detect Hg[Formula: see text] and I[Formula: see text] was evaluated in real examples, and the fluorescence switching can sensitively and selectively detect Hg[Formula: see text] and I[Formula: see text] over some potentially interfering ions, the recoveries were up to 97.8–107.0% and 96.7–106.6%, respectively.

Fluorometric and Spectrophotometric Determination of Pirbuterol Hydrochloride in Authentic and Dosage Forms

1985 ◽  
Vol 68 (6) ◽  
pp. 1222-1225
Author(s):  
Mohamed E Mohamed ◽  
Hassan Y Aboul-Enein
Keyword(s):  
Potentiometric Titration ◽  
Alkaline Medium ◽  
Spectrophotometric Determination ◽  
Fluorescence Intensity ◽  
Perchloric Acid ◽  
Authentic Sample ◽  
Dosage Forms ◽  
Fluorometric Method ◽  
The Mean

Abstract Pirbuterol hydrochloride has been assayed in alkaline medium by using a fluorometric method to measure fluorescence intensity at 372 nm with excitation at 310 nm and by the ▵A method at 242 nm.The linearity ranges are 0.5-4 μg/mL and 10-50 μg/mL, respectively. An authentic pirbuterol HC1 sample was analyzed by nonaqueous potentiometric titration using 0.1N perchloric acid, and the results were compared with those for fluorometric and AA methods. The mean percent recoveries for the authentic sample were 98.72 ± 1.13 and 99.24 ± 0.85, respectively. When applied to commercial capsules containing 10 mg and 15 mg each, the fluorometric method gave mean percent recoveries of 101.11 ± 1.05 and 98.12 ± 0.93; the ▵A method gave mean percent recoveries of 100.57 ± 0.83 and 97.80 ± 0.75, respectively.

Optimizing determination of plasma albumin by the bromcresol green dye-binding method.

1981 ◽  
Vol 27 (1) ◽  
pp. 144-146 ◽  
Author(s):  
W S Robertson
Keyword(s):  
Reaction Time ◽  
Linear Regression ◽  
Human Plasma ◽  
Protein Composition ◽  
Improved Method ◽  
Reaction Conditions ◽  
Plasma Albumin ◽  
Optimal Reaction ◽  
Bromcresol Green

Abstract Some modifications of the conditions of the reaction between plasma and bromcresol green have led to an improved method for determination of plasma albumin with the Vickers M300 multichannel analyzer. Dye concentration and reaction time are the factors principally influencing method specificity, but variable protein composition of human plasma also affects it, so that optimal reaction conditions vary from specimen to specimen. Thus a compromise must be reached such that the best conditions for determining plasma albumin over a range of different protein concentrations are achieved. In the proposed method for the Vickers M300 a reaction time of 12 s (the minimum possible) is used. Comparison with "rocket" immunoelectrophoresis gave the following linear regression: y = 10 + 0.79 x (n = 91; r = 0.96).

Spectrophotometric Determination of Isoniazid in Pharmaceutical Sample by Silicomolybdenum Blue

2014 ◽  
Vol 1033-1034 ◽  
pp. 548-551
Author(s):  
Xin Rong Wen ◽  
Chang Qing Tu
Keyword(s):  
Linear Regression ◽  
Linear Relationship ◽  
Spectrophotometric Determination ◽  
Linear Correlation ◽  
Effect Factors ◽  
Reaction Conditions ◽  
Pharmaceutical Sample ◽  
Novel Method ◽  
Maximum Absorption Wavelength

A novel method for the spectrophotometric determination of isoniazid by silicomoly- bdenum blue has been established.The various effect factors on the spectrophotometric determination of isoniazid by silicomolybdenum blue were investigated in detail.The results showed that under certain reaction conditions,silicomolybdenum yellow could be reduced to silicomolybdenum blue by isoniazid, and the content of isoniazid was determinated indirectly through determinating the absorbance of the silicomolybdenum blue. The maximum absorption wavelength of chromogenic system is 740 nm, good linear relationship is obtained between the absorbance and the concentration of isoniazid in the range of 1.968～27.55 μg/mL,and the equation of the linear regression is A=0.0247+61.824ρ (μg/mL) with a linear correlation coefficient is 0.9995.This proposed method has been successfully applied to determinate of isoniazid in isoniazid tablets, and the results agree well with those obtained by pharmacopoeial method.

Synthesis of fluorescent ionic liquid-functionalized silicon nanoparticles with tunable amphiphilicity and selective determination of Hg2+

2018 ◽  
Vol 6 (48) ◽  
pp. 8214-8220 ◽  
Author(s):  
Quan Li ◽  
Kaite Peng ◽  
Yanzhen Lu ◽  
Aoxin Li ◽  
Fenfang Che ◽  
...  
Keyword(s):  
Ionic Liquid ◽  
Silicon Nanoparticles ◽  
Selective Detection ◽  
Label Free ◽  
Selective Determination ◽  
Highly Sensitive

Label-free fluorescent ionic liquid-functionalized silicon nanoparticles with tunable amphiphilicity for highly sensitive and selective detection of Hg2+ were synthesized.

Silica cross-linked nanoparticles encapsulating a phenothiazine-derived Schiff base for selective detection of Fe(iii) in aqueous media

2014 ◽  
Vol 2 (37) ◽  
pp. 6306-6312 ◽  
Author(s):  
Fangyuan Gai ◽  
Xiang Li ◽  
Tianlei Zhou ◽  
Xiaogang Zhao ◽  
Dongdong Lu ◽  
...  
Keyword(s):  
Schiff Base ◽  
Fluorescence Quenching ◽  
Aqueous Media ◽  
Selective Detection ◽  
Selective Determination ◽  
Design And Synthesis ◽  
Micellar Nanoparticles

This work demonstrates the design and synthesis of an ET-based fluorescence quenching chemosensor using silica cross-linked micellar nanoparticles as scaffolds to encapsulate EDDP for highly selective determination of Fe3+ in aqueous media.

Selective Determination of Pentafluorobenzyl Ester Derivatives of Carboxylic Acids by GC Using Microwave Plasma and Mass Selective Detection

1991 ◽  
Vol 45 (10) ◽  
pp. 1617-1620 ◽  
Author(s):  
Jeffrey H. Brill ◽  
Bikshandarkoil A. Narayanan ◽  
John P. McCormick
Keyword(s):  
Carboxylic Acids ◽  
Microwave Plasma ◽  
Selective Detection ◽  
Capillary Gc ◽  
Selective Determination ◽  
Fragmentation Behavior ◽  
Microwave Induced Plasma ◽  
Characteristic Fragmentation ◽  
Derivatives Of

A highly selective, sensitive method for determination of carboxylic acids in water has been developed that is based on fluorine-selective gas chromatography (GC) detection of pentafluorobenzyl ester derivatives. The atmospheric-pressure helium microwave-induced plasma detector is well suited for fluorine-specific detection of these derivatives, which were well resolved by capillary GC and displayed a characteristic fragmentation behavior when examined by GC-mass selective detection. For demonstration purposes, a number of carboxylic acids, ranging from C1 to C20, were examined and found to be derivatized with yields greater than 90%, and a sample of creek water was examined for its carboxylic acid content.

Fluorometric Determination of Dehydroacetic Acid in Mascara Products

1982 ◽  
Vol 65 (1) ◽  
pp. 82-84
Author(s):  
Francois X Demers ◽  
Ronald L Yates
Keyword(s):  
Fluorescence Intensity ◽  
Calibration Curve ◽  
Fluorometric Method ◽  
Fluorometric Determination ◽  
Dehydroacetic Acid ◽  
Standard Calibration

Abstract A fluorometric method tor the determination of dehydroacetic acid in mascara products was developed. The method is based on the formation of the fluorophore γ-pyroxonium borate, which occurs when dehydroacetic acid is reacted with sulfuric and boric acids. Fluorescence intensity is measured and the amount of dehydroacetic acid is determined from a standard calibration curve. Studies were conducted at the 0.1,0.05, and 0.01% levels. Recoveries ranged from 88 to 106% with an overall average of 99%.

scholarly journals Fluorometric Detection of Thiamine Based on Hemoglobin–Cu3(PO4)2 Nanoflowers (NFs) with Peroxidase Mimetic Activity

Sensors ◽  
2020 ◽  
Vol 20 (21) ◽  
pp. 6359
Author(s):  
Hangjin Zou ◽  
Yang Zhang ◽  
Chuhan Zhang ◽  
Rongtian Sheng ◽  
Xinming Zhang ◽  
...  
Keyword(s):  
Food Production ◽  
Limit Of Detection ◽  
Vitamin B1 ◽  
Tween 80 ◽  
Fluorometric Detection ◽  
Oh Radicals ◽  
Fluorometric Method ◽  
Reaction Conditions ◽  
Optimal Reaction

Component analysis plays an important role in food production, pharmaceutics and agriculture. Nanozymes have attracted wide attention in analytical applications for their enzyme-like properties. In this work, a fluorometric method is described for the determination of thiamine (TH) (vitamin B1) based on hemoglobin–Cu3(PO4)2 nanoflowers (Hb–Cu3(PO4)2 NFs) with peroxidase-like properties. The Hb–Cu3(PO4)2 NFs catalyzed the decomposition of H2O2 into ·OH radicals in an alkaline solution that could efficiently react with nonfluorescent thiamine to fluoresce thiochrome. The fluorescence of thiochrome was further enhanced with a nonionic surfactant, Tween 80. Under optimal reaction conditions, the linear range for thiamine was from 5 × 10−8 to 5 × 10−5 mol/L. The correlation coefficient for the calibration curve and the limit of detection (LOD) were 0.9972 and 4.8 × 10−8 mol/L, respectively. The other vitamins did not bring about any obvious changes in fluorescence. The developed method based on hybrid nanoflowers is specific, pragmatically simple and sensitive, and has potential for application in thiamine detection.

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