Chemiluminescence determination of chromium(VI), molybdenum(VI), and vanadium(V) with bis-(2,4,6-trichlorophenyl) oxalate and perylene

1982 ◽  
Vol 47 (6) ◽  
pp. 1606-1612 ◽  
Author(s):  
Záviš Holzbecher ◽  
Lubomír Kábrt ◽  
Lubomír Janšta
Keyword(s):  
Hydrogen Peroxide ◽  
Standard Deviation ◽  
Oxygen Transfer ◽  
Methyl Acetate ◽  
Catalytic Effect ◽  
Metal Salts ◽  
Experimental Conditions ◽  
Chromium Vi ◽  
Relative Standard

The effect of the experimental conditions (pH, ionic strength, hydrogen peroxide concentration) and of various metal salts on the chemiluminescence occurring during oxidation of bis-(2,4,6-trichlorophenyl) oxalate (TCPO) with hydrogen peroxide in the presence of perylene was studied in water-methyl acetate solutions. The spectrum of the emitted radiation was found practically identical with the fluorescence spectrum of perylene. The observed catalytic effect of Cr(IV), Mo(VI), and V(V) on the chemiluminescence reaction in question can be explained so that these elements form peroxo acids with hydrogen peroxide, thereby facilitating the oxygen transfer from the latter to TCPO. Based on this phenomenon, a method is suggested for the determination of the above elements in concentrations about 10-3 to 10-4 mol l-1; its precision, represented by the relative standard deviation, is about 3-4%, the limits of determination of Cr(VI), Mo(VI), and V(V) are approximately 5-10 μg.

scholarly journals A kinetic method for the determination of phenol

2002 ◽  
Vol 67 (10) ◽  
pp. 661-667 ◽  
Author(s):  
Snezana Mitic ◽  
Valentina Zivanovic
Keyword(s):  
Standard Deviation ◽  
River Water ◽  
Reaction Rate ◽  
Kinetic Method ◽  
Potassium Periodate ◽  
Experimental Conditions ◽  
Inhibiting Effect ◽  
Relative Standard ◽  
Kinetic Expression

Akinetic method for the determination of phenol is proposed. The method is based on the inhibiting effect of phenol on the Mn(II) catalysis of the oxidation of malachite green with potassium periodate. The reaction rate was followed spectrophotometrically at 615 nm. Kinetic expression for the reaction in the presence and absence of phenol are postulated. The optimal experimental conditions for the determination of phenol were established and phenol was determined in concentrations from 30.0 to 188.0 ng/cm3 with a relative standard deviation of 5.5%. The lower detecton limit is 7.8 ng/cm3. The effects of certain foreign ions upon the reaction rate were determined for the assessment of the selectivity of the method. The method was applied for the determination of phenol in tap and river water.

Kinetic Spectrophotometric Determination of Ruthenium by its Catalytic Effect on the Reduction of Spadns with Sodium Hypophosphite in Micellar Media

2012 ◽  
Vol 204-208 ◽  
pp. 4067-4070 ◽  
Author(s):  
Zhi Rong Zhou ◽  
Li Zhen Zhang
Keyword(s):  
Standard Deviation ◽  
Spectrophotometric Method ◽  
Catalytic Effect ◽  
Limit Of Detection ◽  
Fixed Time ◽  
Sodium Hypophosphite ◽  
Micellar Media ◽  
Relative Standard ◽  
Kinetic Spectrophotometric

A simple kinetic spectrophotometric method was developed for the determination of trace amounts of Ru (III). The method is based on the reduction of spadns by sodium hypophosphite (NaH2PO2) in micellar media. The reaction was monitored spectrophotometrically by measuring the decrease in the absorbance of spadns at 515 nm with a fixed-time method. The decrease in the absorbance of spadns is proportional to the concentration of Ru (III) in the range 0.40–10.0 μg/L with a fixed time of 2.5–7.0 min from the initiation of the reaction. The limit of detection is 0.12 μg/L Ru (III). The relative standard deviation for the determination of 0.10 and 0.20 μg/25mL Ru (III) was 2.3 % and 2.0 %, respectively. The method was applied to the determination of Ru (III) in some ores and metallurgy products.

Kinetic Spectrophotometric Method for the Determination of Selenium (IV) by its Catalytic Effect on the Reduction of Arsenazo III with Sodium Hypophosphite in Micellar Media

2012 ◽  
Vol 554-556 ◽  
pp. 926-933
Author(s):  
Zhi Rong Zhou ◽  
Li Zhen Zhang
Keyword(s):  
Standard Deviation ◽  
Relative Standard Deviation ◽  
Spectrophotometric Method ◽  
Catalytic Effect ◽  
Fixed Time ◽  
Sodium Hypophosphite ◽  
Micellar Media ◽  
Relative Standard ◽  
Kinetic Spectrophotometric

A simple and sensitive kinetic spectrophotometric method for the determination of trace selenium (IV) is described, based on its catalytic effect on the reduction arsenazo III (AsA III) with sodium hypophosphite (NaH2PO2) in a solution of 0.02 mol/L sulfuric acid and in the presence of cationic micellar media. The reaction rate is monitored spectrophotometrically by measuring the decrease in absorbance of AsA III at 550 nm with a fixed-time method. The decrease in the absorbance of AsA III is proportional to the concentration of Se(IV) in the range 0.16–1.0 µg/L after a fixed time of 4–10 min from the initiation of the reaction. The limit of detection is 0.049 µg/L Se(IV). The influence of th e factors such as acidity, concentration of reactants, type and concentration of surfactants, reactive time, temperature and co-existing ions on the reaction is discussed. The optimum reaction conditions of reaction are established and some kinetic parameters are determined; the apparent activation energy of catalytic reaction is 59.51 kJ/mol. The relative standard deviation for eleven replicate determination of 0.02, and 0.01µg/25mL Se(IV) was 2.0 % and 2.4 %, respectively. Combined with sulphydryl dextrane gel (SDG) separation and enriching, the method has been successfully applied to the determination of Se (IV) in foodstuff and human hair samples with the relative standard deviation of 2.1 %–5.8 % and the recovery of 97.0 %–103.3 %, the results are in good agreement with those provided by ICP-AES method.

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.

Simplified Spectrophotometric Curcumin Method for the Determination of Boron in Marine Shellfish

1975 ◽  
Vol 32 (6) ◽  
pp. 813-816 ◽  
Author(s):  
R. E. Drew
Keyword(s):  
Hydrogen Peroxide ◽  
Standard Deviation ◽  
Acetic Anhydride ◽  
Sulphuric Acid ◽  
Relative Standard Deviation ◽  
Tissue Sample ◽  
Total Error ◽  
Relative Standard ◽  
Wet Weight

The method involves a sulphuric acid–hydrogen peroxide digestion of the tissue sample at 100 C, dehydration of the digest with acetic anhydride, formation of the boron–curcumin complex (rosocyanin), followed by buffering of the solution and measurement of the absorbance at 545 nm. Data are presented to show that a mean relative standard deviation of approximately 5% and a mean total error of approximately 12% can be expected for shellfish in the concentration range of 1.0–10.0 μg B/g wet weight tissue (ppm).

scholarly journals Ultrasensitive determination of amoxicillin using chemiluminescence with flow injection analysis

2006 ◽  
Vol 20 (1) ◽  
pp. 37-43 ◽  
Author(s):  
Xiaofeng Xie ◽  
Zhenghua Song
Keyword(s):  
Hydrogen Peroxide ◽  
Standard Deviation ◽  
Detection Limit ◽  
Flow Injection ◽  
Pharmaceutical Preparations ◽  
Chemiluminescence Intensity ◽  
Relative Standard ◽  
Human Urine And Serum ◽  
Urine And Serum

Results presented here reveal that amoxicillin can greatly enhance the chemiluminescence intensity generated from the reaction between luminol and hydrogen peroxide. The increment chemiluminescence signal was linearly dependent on amoxicillin concentration in the range from 10 pg·ml−1to 2 ng·ml−1(r2=0.9978) offering a detection limit as low as 3.5 pg·ml−1(3σ). At a flow rate of 2.0 ml·min−1, one analysis cycle, including sampling and washing, can be accomplished in 20 s with a relative standard deviation of less than 5%. The sensitive flow injection method was applied successfully to determine of amoxicillin in pharmaceutical preparations, human urine and serum without any pretreatment procedure, with recovery from 90.0% to 110.0% and relative standard deviations of less than 5.0%.

Kinetic Spectrophotometric Determination of Selenium (IV) by its Catalytic Effect on the Oxidation of Acid Chrome Blue K by Hydrogen Peroxide

2012 ◽  
Vol 538-541 ◽  
pp. 2358-2363 ◽  
Author(s):  
Zhi Rong Zhou ◽  
Li Zhen Zhang
Keyword(s):  
Hydrogen Peroxide ◽  
Standard Deviation ◽  
Relative Standard Deviation ◽  
Limit Of Detection ◽  
Fixed Time ◽  
Relative Standard ◽  
Kinetic Spectrophotometric ◽  
Acid Chrome Blue K ◽  
Good Agreement

Based on the oxidation of acid chrome blue K (ACBK) by hydrogen peroxide in 0.002 mol/L sulfuric acid solution, while 1,10-phenanthroline (phen) acts as an activator, 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 ACBK at 524 nm with a fixed-time method. The decrease in the absorbance of ACBK is proportional to the concentration of Se (IV) in the range 0.06–1.0 µg/L with a fixed time of 4–10 min from the initiation of the reaction. The limit of detection is 0.018 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 62.30 kJ/mol. The relative standard deviation for 11 replicate determination of 0.01 and 0.02 µg/25mL selenium (III) was calculated to be 2.3 % and 2.0 %, respectively. Combined with sulphydryl dextrane gel (SDG) separation and enriching, the method has been successfully applied to the determination of Se (IV) in foodstuff samples with the relative standard deviation of 1.1 %–3.7 % and the recovery of 99.0 %–104.0 %, the results are in good agreement with those provided by HG-AAS method.

scholarly journals Two Spectrophotometric Assays for Dopamine Derivatives in Pharmaceutical Products and in Biological Samples of Schizophrenic Patients Using Copper Tetramine Complex and Tri-iodide Reagent

2005 ◽  
Vol 2005 (1) ◽  
pp. 1-9 ◽  
Author(s):  
F. A. Nour El-Dien ◽  
M. A. Zayed ◽  
Gehad. G. Mohamed ◽  
Reham G. El-Nahas
Keyword(s):  
Standard Deviation ◽  
Degradation Products ◽  
Outer Sphere ◽  
Pharmaceutical Products ◽  
Official Method ◽  
Good Precision ◽  
Experimental Conditions ◽  
Relative Standard ◽  
Schizophrenic Patients

Two simple, rapid, and sensitive spectrophotometric methods are proposed for the determination of levodopa (LD). The first method is based on coupling of 4-aminoantipyrine (4-AAP) with one of the dopamine derivatives (LD, CD) to give a new ligand that reacts with copper tetramine complex to give intensely colored chelates. The colored products are quantified spectrophotometrically at 525 and 520 nm for LD and CD, respectively. The optimization of the experimental conditions is described. The method has been used for the determination of19.7–69.0and18.1–54.3μg mL−1of LD and CD, respectively. The accuracy of the method is achieved by the values of recovery (100±0.2%) and the precision is supported by the low standard deviation (SD=0.17–0.59) and relative standard deviation (CV=0.4%–1.54%) values. The second method is based on the formation of ion-pair iodinated inner sphere or outer sphere colored complexes between the LD and triiodide ions at pH 5 and room temperature (23±3°C). This method has been used for the determination of LD within the concentration range39.44–78.88μg mL−1with SD=0.22–0.24and recovery percent=100±0.3%. The sensitivity of the two methods is indicated by Sandell's sensitivity of0.014–0.019g cm−2. The results of the two methods are compared with those of the official method. The interference of common drug additives, degradation products, and excipients was also studied. The proposed methods were applied successfully to the determination of the LD-CD synthetic mixture and Levocare drug. The determination of LD in urine of some schizophrenic patients was applied with good precision and accuracy. The reliability of the methods was established by parallel determinations against the official British pharmacopoeia method.

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