Cloud Point Extraction-Fluorimetric Combined Methodology for the Determination of Magnolol

2013 ◽  
Vol 699 ◽  
pp. 34-39
Author(s):  
Li Liu ◽  
Xia Shi Zhu
Keyword(s):  
Standard Deviation ◽  
Detection Limit ◽  
Cloud Point ◽  
Relative Standard Deviation ◽  
Cloud Point Extraction ◽  
Calibration Graph ◽  
Optimum Conditions ◽  
Relative Standard ◽  
Triton X

A new Triton X-114 cloud point extraction combined with fluorometry method for analysis of magnolol in drug samples was developed. Under the optimum conditions, the calibration graph was linear in the range of 2.0-150.0ng/mL of magnolol in the initial solution with r = 0.9998. Detection limit (DL) was 0.03ng/mL (S/N=3) and the relative standard deviation (RSD) for 20.0ng/mL of magnolol was 2.79%(n=11). The method was successfully applied for the determination of magnolol in drug samples with satisfactory results.

Cloud Point Extraction and Spectrophotometry Determination of Lead in Environment Water Using 5-Br-PADAP

2013 ◽  
Vol 830 ◽  
pp. 345-348
Author(s):  
Lin Gao ◽  
Sheng Jie Chen ◽  
Fang Chen ◽  
Wen Hong Zhou ◽  
Jun Long Yao
Keyword(s):  
Cloud Point ◽  
Cloud Point Extraction ◽  
Detection Method ◽  
Low Cost ◽  
Calibration Graph ◽  
Buffer Solution ◽  
Relative Standard ◽  
Triton X ◽  
Optimized Conditions

A simple, sensitive, green and low cost detection method based on the cloud point extraction (CPE) separation and spectrophotometry was proposed for the determination of lead. In pH=9.0 H3BO3 buffer solution, Pb(II) reacts with 2-(5-bromo-2-pyridylazo)-5-diethylaminophenol (5-Br-PADAP) in the presence of Triton X-100 yielding a hydrophobic complex, which then is extracted into micro-volume surfactant-rich phase. The calibration graph was linear in the range of 20-400 µg/L (at 560 nm). Under the optimized conditions, the detection limits of 10.94 µg/L and the relative standard deviations(RSD) of 2.0% (n=5) for Lead(II) were found, respectively. The sensitivity and absorbance of this method are at least five times higher when compared with that of usual 5-Br-PADAP spectrophotometry without CPE, and the proposed method has been applied to the determination of Lead in environment water samples with satisfactory results.

A Study on Gadolinium Sensitized Chemiluminescence System

2012 ◽  
Vol 535-537 ◽  
pp. 1337-1340 ◽  
Author(s):  
Chi Yang ◽  
Nai Lin Ren
Keyword(s):  
Standard Deviation ◽  
Detection Limit ◽  
Linear Relationship ◽  
Relative Standard Deviation ◽  
Optimum Conditions ◽  
Chemiluminescence Intensity ◽  
Experimental Conditions ◽  
Relative Standard

A new chemiluminescence system was built by using gadolinium as sensitizer, and the analysis capabilities of this system was tested as below. The method is based on chemluminescence of Ce (IV)-SO32- sensitized by Gd3+-OFLX. The effects of some critical experimental conditions were discussed and the optimum conditions for chemluminescence emission were investigated. The linear relationship between the relative chemiluminescence intensity and the concentration of OFLX is in the range of 2×10-9 g/mL～5×10-7 g/mL with a detection limit of 1.0×10-9g/mL .The relative standard deviation is 2.8% (n=11) for a level of 5.0×10-7 g/mL. The method has been applied to the analysis of OFLX in tablets with satisfactory results.

Determination of diltiazem based on the reduction of Cu(II)–BCA complexes in micellar medium

2010 ◽  
Vol 88 (6) ◽  
pp. 533-539 ◽  
Author(s):  
Larissa Zuppardo Lacerda Sabino ◽  
Daniele Cestari Marino ◽  
Horacio Dorigan Moya
Keyword(s):  
Standard Deviation ◽  
Relative Standard Deviation ◽  
Confidence Level ◽  
Limit Of Detection ◽  
Calibration Graph ◽  
Micellar Medium ◽  
Solution Ph ◽  
Simple Method ◽  
Relative Standard

A simple method was developed for determining microquantities of diltiazem, based on the reduction of copper(II) in buffered solution (pH 7.0) and the use of a micellar medium containing 4,4′-dicarboxy-2,2′-biquinoline acid. The copper(I) produced reacts with 4,4′-dicarboxy-2,2′-biquinoline acid and the complexes formed are spectrophotometrically measured at 558 nm. A typical calibration graph shows good linearity (r = 0.993) from 20 to 100 μg mL–1 of diltiazem. The limit of detection and relative standard deviation were calculated as 12 μg mL–1 (99% confidence level) and 3.5% (40 μg mL–1; n = 6), respectively, with a mean recovery value of 96.5% found in pharmaceutical dosages. A straightforward and effective way to recycle the reagents is addressed. The hazardous aspects of the Cu(I)–BCA reaction are presented as well.

Iodometric determination of 2-mercaptobenzthiazole by coulometric titration

1982 ◽  
Vol 47 (2) ◽  
pp. 588-593 ◽  
Author(s):  
Zdeněk Kučera ◽  
Milan Karlík ◽  
Jiří Krofta
Keyword(s):  
Standard Deviation ◽  
Relative Standard Deviation ◽  
Coulometric Titration ◽  
Optimum Conditions ◽  
End Point ◽  
Relative Standard ◽  
Standard Deviations

The optimum conditions were found for the determination of 2-mercaptobenzthiazole (MBT) by coulometric titration with the generated iodine using biamperometric indication of the titration end point. Use is made of the oxidation to the disulphide (n = 1) and to benzothiazole-2-sulphinate (n = 4) in the regions pH 4.5-8.5 and 10-12, respectively. Eight repeated titrations to the disulphide gave the relative standard deviations 0.27% and 1.23% in the determination of 1 675 and 33.5 μg MBT, respectively, seven repeated titrations of 419 μg MBT to benzothiazole-2-sulphinate afforded results with the relative standard deviation 0.34%.

scholarly journals A New Spectrophotometric Method for Determination of Selenium in Cosmetic and Pharmaceutical Preparations after Preconcentration with Cloud Point Extraction

2011 ◽  
Vol 2011 ◽  
pp. 1-8 ◽  
Author(s):  
Mohammad Hosein Soruraddin ◽  
Rouhollah Heydari ◽  
Morteza Puladvand ◽  
Mir Mehdi Zahedi
Keyword(s):  
Cloud Point ◽  
Spectrophotometric Method ◽  
Cloud Point Extraction ◽  
Pharmaceutical Preparations ◽  
Pharmaceutical Samples ◽  
Relative Standard ◽  
Replicate Measurements ◽  
Triton X ◽  
Preconcentration Method

A simple, rapid, and sensitive spectrophotometric method for the determination of trace amounts of selenium (IV) was described. In this method, all selenium spices reduced to selenium (IV) using 6 M HCl. Cloud point extraction was applied as a preconcentration method for spectrophotometric determination of selenium (IV) in aqueous solution. The proposed method is based on the complexation of Selenium (IV) with dithizone at pH < 1 in micellar medium (Triton X-100). After complexation with dithizone, the analyte was quantitatively extracted to the surfactant-rich phase by centrifugation and diluted to 5 mL with methanol. Since the absorption maxima of the complex (424 nm) and dithizone (434 nm) overlap, hence, the corrected absorbance, Acorr, was used to overcome the problem. With regard to the preconcentration, the tested parameters were the pH of the extraction, the concentration of the surfactant, the concentration of dithizone, and equilibration temperature and time. The detection limit is 4.4 ng mL-1; the relative standard deviation for six replicate measurements is 2.18% for 50 ng mL-1of selenium. The procedure was applied successfully to the determination of selenium in two kinds of pharmaceutical samples.

Spctrophotometric Determination of Trace Ruthenium by its Catalytic Effect on Oxidation of 3,5-DiBr-PADAP with KIO4

2012 ◽  
Vol 554-556 ◽  
pp. 1999-2005
Author(s):  
Zhi Rong Zhou ◽  
Qun Wang ◽  
Shu Yuan Zhang
Keyword(s):  
Activation Energy ◽  
Standard Deviation ◽  
Detection Limit ◽  
Catalytic Reaction ◽  
Oxidation Reaction ◽  
Catalytic Effect ◽  
Optimum Conditions ◽  
Potassium Periodate ◽  
Relative Standard

A spectrophotometric method for the determination of ruthenium (III) is described, based on its catalytic effect on the oxidation reaction of 2-[(3,5-dibromo-2-pyridy)azo]-5-diethylaminophenol (3,5-diBr-PADAP) with potassium periodate in 0.008 mol/L sodium hydroxide medium and in the presence of OP emulsifier (p-iso-octyl phenoxy polyethoxy ethanol) at 100 °C. The above reaction is followed spectrophotometrically by measuring the decrease in the absorbance at 530 nm for the catalytic reaction of 3,5-diBr-PADAP. The calibration curve for the recommended method was linear in the concentration range over 0.04 µg/L–1.0 µg/L and the detection limit of the method for Ru (III) is 0.012 µg/L. The influence of the factors such as acidity, concentration of reactants, reaction time, temperature and co-existing ions on the reaction is discussed. The optimum conditions of reaction are established and some kinetic parameters are determined. The apparent activation energy of catalytic reaction is 100.48 kJ/mol. The relative standard deviation for the determination of ruthenium (III) at the concentration of 0.02 µg/25mL is calculated to be 2.30 % (n=11). In combination with distilled separation, the method has been successfully applied for the determination of trace ruthenium (III) in some ores and metallurgy products with the relative standard deviations (RSD) over 1.8 %–2.9 % and the recovery over 98.1 %–103.1 %.

Determination of Trace Chromium (VI) in Tanning Wastewater by Flow Injection Spectrophotometry

2010 ◽  
Vol 113-116 ◽  
pp. 1732-1734
Author(s):  
Xin Zhao ◽  
Zhi Hui Sui ◽  
Jing Bin Zhang
Keyword(s):  
Standard Deviation ◽  
Relative Standard Deviation ◽  
Flow Injection ◽  
Spectrophotometric Method ◽  
H2so4 Solution ◽  
Optimum Conditions ◽  
Chromium Vi ◽  
Relative Standard ◽  
Simple Flow

In 1.0 mol/L H2SO4 solution, a rapid and simple flow—injection spectrophotometric method has been developed for Cr(Ⅵ) determination, based on the violet—red Cr(Ⅵ)—diphenylcarbazide chelates formed by reactions. The results show, under optimum conditions, the maximum absorption of the complex is at 540 nm and the detection limits of the method is 0.0136mg/L for Cr(Ⅵ) and Beer’s law is obeyed for Cr(Ⅵ) in the range of 0.03—1.60mg/L. The determination frequency is l00 times/h. The relative standard deviation of eleven replicates is less than 4.0%. The method has been applied to the determination of trace Cr(Ⅵ) in tanning wastewater with satisfactory results.

Study on the Kinetic Spectrophotometric Determination of Selenium (IV) on Oxidation of Neutral Red with Potassium Periodate and its Application

2012 ◽  
Vol 610-613 ◽  
pp. 446-451
Author(s):  
Zhi Rong Zhou ◽  
Li Zhen Zhang
Keyword(s):  
Standard Deviation ◽  
Relative Standard Deviation ◽  
Limit Of Detection ◽  
Fixed Time ◽  
Neutral Red ◽  
Optimum Conditions ◽  
Hair Samples ◽  
Relative Standard ◽  
Kinetic Spectrophotometric

Based on the oxidation of neutral red by KIO4 in 3.2×10-4 mol/L sulfuric acid solution, a simple kinetic spectrophotometric method was developed for the determination of trace amounts of Se(IV).The reaction was monitored spectrophotometrically by measuring the decrease in the absorbance of neutral red at 530 nm with a fixed-time method. The decrease in the absorbance of neutral red is proportional to the concentration of Se(IV) in the range 0.0–8.0 µg/L with a fixed time of 4–6 min from the initiation of the reaction. The limit of detection is 0.36 µg/L Se(IV). The influence of the factors such as acidity, concentration of reactants, reaction time, temperature and co-existing ions on the reaction is discussed. The optimum conditions of reaction are established and some kinetic parameters are determined. The apparent activation energy of catalytic reaction is 81.60 kJ/mol. The relative standard deviation for the determination of 0.1 and 0.2 µg/mL Se(IV) was 2.1 and 1.9 %, respectively. The method has been successfully applied to the determination of Se (IV) in tea and human hair samples with the relative standard deviation of 0.33 %–1.5 % and the recovery of 97.5 %–103.5 %.

Novel Analytical Approach for the Determination of Zirconium and Yttrium in Ysz Powders

2012 ◽  
Vol 51 (4) ◽  
pp. 428-435
Author(s):  
A. Zarkov ◽  
A. Zalga ◽  
S. Tautkus ◽  
A. Kareiva
Keyword(s):  
Standard Deviation ◽  
Relative Standard Deviation ◽  
Analytical Approach ◽  
Analytical Procedure ◽  
Sol Gel ◽  
Calibration Graph ◽  
Gel Method ◽  
Spectrophotometric Methods ◽  
Relative Standard

Two simple and sensitive spectrophotometric methods for the determination of zirconium and yttrium in YSZ specimens have been suggested in this study. The calibration graph for zirconium and yttrium was linear in the range of 0.08-0.4 and 0.1-0.6 μg/mL, respectively. The proposed analytical procedure was applied for the determination of zirconium and yttrium in the YSZ samples synthesized by aqueous sol-gel method. The relative standard deviation (RSD) for zirconium was in the range from 0.6 to 4.5%, for yttrium it was from 0.6 to 3.6%. The achieved results demonstrated that the suggested procedure could be successfully applied for the analysis of YSZ powders with satisfactory accuracy.

scholarly journals Optimisation and Evaluation of Zinc in Food Samples by Cloud Point Extraction and Spectrophotometric Detection

2019 ◽  
Vol 16 (1) ◽  
pp. 41 ◽  
Author(s):  
Nurul Azwa Mohd Azizi ◽  
Nurul Yani Rahim ◽  
Muggundha Raoov Ramachandran ◽  
Saliza Asman
Keyword(s):  
Cloud Point ◽  
Cloud Point Extraction ◽  
Ethylenediaminetetraacetic Acid ◽  
Food Samples ◽  
Complexation Reaction ◽  
Canned Food ◽  
Spectrophotometric Detection ◽  
Relative Standard ◽  
Triton X

The cloud point extraction (CPE) method was developed to determine the zinc prior to Ultraviolet-visible (UV-Vis) spectrophotometry detection. Triton X-100 was applied as extractant based on the complexation reaction of Zn(II) ions with ethylenediaminetetraacetic acid (EDTA). Under optimal conditions, the CPE was used to determine the concentration of zinc in canned food samples. The amounts of zinc found in the food samples were in the range of 0.005-0.007 mg/L with relative standard deviation (RSD) of < 8 %. This confirmed that the proposed CPE method is suitable for the determination of zinc in food samples, indicating the concentration of zinc was within the permissible limit.

Sign in / Sign up

Export Citation Format

Share Document