scholarly journals Extractive Spectrophotometric Method for Determination of Molybdenum in Steels and Environmental Samples

2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
Rameshwar Dass ◽  
Jitander K. Kapoor ◽  
Sunita Gambhir
Keyword(s):  
Ascorbic Acid ◽  
Standard Deviation ◽  
Spectrophotometric Method ◽  
Environmental Samples ◽  
Room Temperature ◽  
Molar Absorptivity ◽  
Accuracy And Precision ◽  
Relative Standard ◽  
Improved Accuracy

An extractive spectrophotometric method has been developed for microdetermination of molybdenum. At room temperature Mo(VI) was reduced to Mo(V) in 2 M H2SO4using ascorbic acid as a reductant. The Mo(V) formed a yellow-coloured (1 : 2) complex with 6-chloro-3-hydroxy-2-(3′-hydroxyphenyl)-4-oxo-4H-1-benzopyran (CHHB). The complex was quantitatively extracted into toluene and absorbed maximum atλmax404 nm. Beer’s law was obeyed over the concentration range of 2.31 μg Mo ml−1with a molar absorptivity and Sandell's sensitivity of5.62×104 L mol−1 cm−1and 0.0016 μg Mo cm−2, respectively. The relative standard deviation was 0.0025 (in absorbance units) for 10 replicate determinations of 1 μg Mo ml−1. The method was free from the interference of large number of analytically important elements. Molybdenum has been determined satisfactorily in different technical, synthetic, and environmental samples with improved accuracy and precision.

scholarly journals Development and validation of spectrophotometric method for phenylephrine hydrochloride estimation in nasal drops formulations

2008 ◽  
Vol 27 (2) ◽  
pp. 149 ◽  
Author(s):  
Ivana Savić ◽  
Goran Nikolić ◽  
Vladimir Banković
Keyword(s):  
Standard Deviation ◽  
Sodium Hydroxide ◽  
Relative Standard Deviation ◽  
Spectrophotometric Method ◽  
Molar Absorptivity ◽  
Dosage Forms ◽  
Phenylephrine Hydrochloride ◽  
Relative Standard ◽  
Development And Validation

Simple, accurate and reproducible UV-spectrophotometric method was developed and validated for the estimation of phenylephrine hydrochloride in pharmaceutical nasal drops formulations. Phenylephrine hydrochloride was estimated at 291 nm in 1 mol⋅dm-3 sodium hydroxide (pH 13.5). Beer’s law was obeyed in the concentration range of 10–100 μg⋅cm−3 (r2 = 0.9990) in the sodium hydroxide medium. The apparent molar absorptivity was found to be 1.63×103 dm3⋅mol−1⋅cm−1. The method was tested and validated for various parameters according to the ICH (International Conference on Harmonization) guidelines. The detection and quantitation limits were found to be 0.892 and 2.969 μg⋅cm−3, respectively. The proposed method was successfully applied for the determination of phenylephrine hydrochloride in pharmaceutical nasal drops formulations. The results demonstrated that the procedure is accurate, precise and reproducible (relative standard deviation < 1 %), while being simple, cheap and less time consuming, and hence can be suitably applied for the estimation of phenylephrine hydrochloride in different dosage forms.

scholarly journals Spectrophotometric Method for Determination of Paraquat in Food and Biological Samples

1997 ◽  
Vol 80 (2) ◽  
pp. 388-391 ◽  
Author(s):  
Ritu Kesari ◽  
Manish Rai ◽  
Vinay Kumar Gupta
Keyword(s):  
Standard Deviation ◽  
Metal Ions ◽  
Relative Standard Deviation ◽  
Alkaline Medium ◽  
Spectrophotometric Method ◽  
Biological Samples ◽  
Molar Absorptivity ◽  
Relative Standard ◽  
Sensitive Spectrophotometric Method

Abstract A sensitive spectrophotometric method was developed for determination of paraquat, a widely used herbicide. Paraquat was reduced with glucose in an alkaline medium, and the blue radical ion obtained was measured at 600 nm. Beer’s law was obeyed at 0.1–1.2 ppm paraquat. The molar absorptivity was 1.26 × 105 L mol-1 cm-1. The standard deviation and relative standard deviation were ± 0.007 and 2.0%, respectively, for 5 μg paraquat/10 mL analyzed over 7 days. The method was free from interference by other commonly used pesticides and metal ions. The method may be used to the determine paraquat in plants, fruits, grains, water, blood, and urine.

scholarly journals Flotation-Spectrophotometric Method for the Determination of Aluminium ion Using Xylenol Orange

2011 ◽  
Vol 8 (4) ◽  
pp. 1528-1535 ◽  
Author(s):  
F. Nekouei ◽  
Sh. Nekouei
Keyword(s):  
Standard Deviation ◽  
Spectrophotometric Method ◽  
Calibration Curve ◽  
Limit Of Detection ◽  
Xylenol Orange ◽  
Molar Absorptivity ◽  
Relative Standard ◽  
Ion Associate ◽  
Sensitive Method

A simple, fast, reproducible and sensitive method for the flotation- spectrophotometric determination of Al3+is reported. The apparent molar absorptivity (ε) of the ion associate was determined to be 8.35×104L mol-1cm-1. The calibration curve was linear in the concentration range of 1.0-50 ng mL-1of Al3+with a correlation coefficient of 0.9997. The limit of detection (LOD) was 0.621 ng mL. The relative standard deviation (RSD) at 10 and 30 ng mL-1of aluminium were 1.580 and 2.410% (n=7) respectively. The method was applied for measuring the amount of aluminium in water samples.

Spectrophotometric Determination of Boron in Dates of Some Cultivars Grown in Saudi Arabia

1993 ◽  
Vol 76 (3) ◽  
pp. 601-603 ◽  
Author(s):  
A A Al-Warthan ◽  
S S Al-Showiman ◽  
S A Al-Tamrah ◽  
A A BaOsman
Keyword(s):  
Saudi Arabia ◽  
Standard Deviation ◽  
Relative Standard Deviation ◽  
Spectrophotometric Determination ◽  
Spectrophotometric Method ◽  
Molar Absorptivity ◽  
Relative Standard ◽  
Sensitive Spectrophotometric Method

Abstract The formation of a red complex between boron and the quinalizarin reagent was investigated and used as the basis for a simple and sensitive spectrophotometric method for boron in date cultivars. At 620 nm, the absorbance was linear (r= 0.999) over the 0.25-2.5 μg/mL concentration range. The molar absorptivity was found to be 2.23 x 103mol-1cm-1 and the relative standard deviation for 10 replicates (1.0 μg/mL) was 0.97%.

scholarly journals Spectrophotometric Method for the Determination of Drugs Containing Phenol Group by Using 2, 4- Dinitrophenylhydrazine

2010 ◽  
Vol 7 (2) ◽  
pp. 395-402
Author(s):  
Padmarajaiah Nagaraja ◽  
Ashwinee Kumar Shrestha
Keyword(s):  
Standard Deviation ◽  
Spectrophotometric Method ◽  
Limit Of Detection ◽  
Dosage Forms ◽  
Limit Of Quantification ◽  
Pharmaceutical Dosage Forms ◽  
Accuracy And Precision ◽  
Relative Standard ◽  
Phenolic Drugs

A spectrophotometric method has been proposed for the determination of four phenolic drugs; salbutamol, ritodrine, amoxicillin and isoxsuprine. The method is based on the oxidation of 2, 4- dinitrophenyl-hydrazine and coupling of the oxidized product with drugs to give intensely colored chromogen. Under the proposed optimum condition, beer’s law was obeyed in the concentration range of 2.5-17, 2-29, 4-33 and 5-30 μg/mL for salbutamol, ritodrine, amoxicillin and isoxsuprine respectively. The limit of detection (LOD) and limit of quantification (LOQ) were 0.2, 0.83, 0.09, 0.84 μg/mL and 0.66, 2.79, 0.3 and 2.81 μg/mL in the same order. No interference was observed from common pharmaceutical adjuvants. The ringbom plots and low relative standard deviation assert the applicability of this method. The suggested method was further applied for the determinations of drugs in commercial pharmaceutical dosage forms, which was compared statistically with reference methods by means oft- test andF- test and were found not to differ significantly at 95% confidence level. The procedure is characterized by its simplicity with accuracy and precision.

scholarly journals Spectrophotometric Method for the Determination of Paracetamol

1970 ◽  
Vol 24 ◽  
pp. 39-44 ◽  
Author(s):  
Buddha Ratna Shrestha ◽  
Raja Ram Pradhananga
Keyword(s):  
Standard Deviation ◽  
Spectrophotometric Method ◽  
Trace Amount ◽  
Pharmaceutical Preparation ◽  
Chemical Society ◽  
Molar Absorptivity ◽  
Coupling Agents ◽  
Clinical Samples ◽  
Relative Standard

Paracetamol with 1-napthol or resorcinol gave azodye and the concentration of paracetamol was investigated spectrophotometrically. The azodyes formed with both 1-napthol and resorcinol as coupling agents follow Lambert Beer's law in the range of 0 to 10 µgmL-1 of paracetamol. The molar absorptivity and Sandell's sensitivity for azodye coupled with 1-napthol were found to be 1.68×104 Lmol-1cm-1 and 9.0 ngmL-1cm-2, respectively. The molar absorptivity and Sandell's sensitivity for azodye coupled with resorcinol were found to be 2.86×104 Lmol-1cm-1 and 5.3 ngmL-1cm-2, respectively. Both coupling agents had been applied successfully in the analysis of paracetamol in pharmaceutical preparation. The relative standard deviation for all five samples ranged from 2.2-6.4% at 95% confidence. The percentage recoveries were found to range from 97.8 to 103.4. Both methods used in the present study may be applied to the determination of trace amount of paracetamol in different clinical samples. Keyword: Paracetamol; Spectrophotometric; 1-napthol; Resorcinol DOI: 10.3126/jncs.v24i0.2389 Journal of Nepal Chemical Society Vol. 24, 2009 Page: 39-44

Spectrophotometric Method for Microdetermination of Nitrogen in Kjeldahl Digest

1989 ◽  
Vol 72 (6) ◽  
pp. 953-956 ◽  
Author(s):  
Muljibhai B Devani ◽  
Chamanlal J Shishoo ◽  
Shailesh A Shah ◽  
Bhanubhai N Suhagia
Keyword(s):  
Standard Deviation ◽  
Nitrogen Content ◽  
Spectrophotometric Method ◽  
Acidic Medium ◽  
Molar Absorptivity ◽  
Nitrogen Compounds ◽  
Relative Standard ◽  
Kjeldahl Method ◽  
Aoac Method

Abstract A new spectrophotometric method for the determination of nitrogen in Kjeldahl digest has been developed. The method is based on the reaction of ammonia with acetylacetone-formaldehyde reagent in aqueous medium to yield yellow 3,5-diacetyl- 1,4-dihydrolutidine with a characteristic absorption maxima at 412 nm. The effect of several experimental variables on the determination of nitrogen was studied. The method was suitable for determination of nitrogen in acidic medium without interference from the usual catalysts employed for the digestion in Kjeldahl method. Lambert-Beer’s law is obeyed in the concentration range of 0.5-6.0 ng nitrogen/mL in the reaction mixture. The molar absorptivity in terms of nitrogen was 1.4 X 103L mol-1 cm-1. The standard deviation and relative standard deviation were ±0.0447 and ±0.896% (n = 10), respectively. The method is simple, rapid, and precise. A variety of carbocyclic and heterocyclic nitrogen compounds have been analyzed for nitrogen content. The results are comparable with those obtained by AOAC method, 47.021.

scholarly journals A Rapid and Direct Sensitive Spectrophotometric Method for the Determination of Molybdenum(VI) using Gallacetophenone Phenylhydrazone with Application to Alloy Steel Samples

2011 ◽  
Vol 8 (3) ◽  
pp. 1362-1370 ◽  
Author(s):  
D. Venkataramana Reddy ◽  
P. V. Chalapathi ◽  
A. Varada Reddy
Keyword(s):  
Alloy Steel ◽  
Spectrophotometric Method ◽  
Room Temperature ◽  
Molar Absorptivity ◽  
Analysis Method ◽  
Slope Analysis ◽  
Relative Standard ◽  
Analytical Reagent ◽  
Ph Range

A rapid, sensitive and fairly selective spectrophotometric method has been developed for the determination of molybdenum(VI) using gallacetophenone phenylhydrazone (GPPH) as an analytical reagent. The GPPH forms an orange red species of molybdenum(VI) at a pH range of 3.0-4.0 and the complex is soluble in 20% ethanol. The Mo(VI)-GPPH complex shows maximum absorbance at 375 nm with molar absorptivity and Sandellʼs sensitivity being 1.539x104L/mol cm and 1.5x10-3μg cm-2respectively. The system obeys Beerʼs law in the range of 1.0-6.0 μg/mL. The repeatability of the method was checked by finding the relative standard deviation. The composition of the Mo(VI)-GPPH complex is established as 1:2 by slope analysis method. The instability constant of the complex calculated from Edmond and Birnbaumʼs method is 6.785x10-8at room temperature. The interfering effect of various cations and anions has also been studied. The method has been applied for the determination of Mo(VI) in alloy steel samples.

Assessment of Fenvalerate in Water, Soil and Vegetable Samples

2021 ◽  
Vol 30 (1) ◽  
pp. 60-65
Author(s):  
Mamta Nirmal ◽  
Prashant Mundeja ◽  
Kalpana Wan ◽  
Vindhiya Patel ◽  
Raisa Khatoon ◽  
...  
Keyword(s):  
Standard Deviation ◽  
Relative Standard Deviation ◽  
Environmental Samples ◽  
Molar Absorptivity ◽  
Vegetable Samples ◽  
Maximum Absorbance ◽  
Relative Standard ◽  
Hydrolysis Of ◽  
Solution Volume

Simple and sensitive spectrophotometric scheme was described for the determination of fenvalerate in environmental samples. The scheme was based on the hydrolysis of 1 N of 5 mL NaOH to form cyanohydrin. The cyanohydrin is reacted with bromine and pyridine to form glutaconic aldehyde, which is then coupled with p-Dimethylaminobenzaldehyde to give yellow dye having maximum absorbance at 440 nm. Beer’s law is obeyed over the concentration range of 0.6- 6.2 µg in a nal solution volume of 25 mL. The molar absorptivity of the colored system is 3.84×104 L mol-1cm-1 and Sandell’s sensitivity is 2.4×10-3 µg cm-2. The reproducibility assessed by carrying out seven days replicate analysis of a solution containing 0.6 µg of fenvalerate in a nal solution volume of 25 mL. The standard deviation and relative standard deviation for the absorbance value were found to be ± 3.4×10-3 and 1.5% respectively. The proposed scheme is sensitive and free from the interference of other toxicants. The analytical parameters were optimized and the scheme was applied to the determination of fenvalerate in environmental samples.

scholarly journals A New Spectrophotometric Method for Hydrogen Sulphide Through Electrolytically Generated Mn(III) WithO-Tolidine

2008 ◽  
Vol 5 (1) ◽  
pp. 93-99 ◽  
Author(s):  
M. S. Suresha ◽  
Mansour S. Abdul Galil ◽  
Mahadevaiah ◽  
M. A. Sathish ◽  
M. S. Yogendra Kumar ◽  
...  
Keyword(s):  
Standard Deviation ◽  
Hydrogen Sulphide ◽  
Spectrophotometric Method ◽  
Water Samples ◽  
Molar Absorptivity ◽  
Official Method ◽  
Color Intensity ◽  
Orange Yellow ◽  
Relative Standard

A simple, sensitive and economical spectrophotometric method for the determination of hydrogen sulphide is developed. The method is based on a redox reaction in that Mn(III) generated electrolytically is taken in excess, which is oxidizing a known but a less quantity of hydrogen sulphide and the unreacted oxidant will oxidize furthero-tolidine to produce an orange yellow quinonediimine absorbing cation (λ max. 455 nm). Therefore, in principle, the decrease in color intensity of the absorbing system is proportional to the concentration of hydrogen sulphide. The stoichiometry between Mn(III) ando-tolidine and stability constant of the complex were determined by Job's continuous method, the corresponding values were found to be 2:1 and 1.42X105Lmol-1. The system was obeying Lambert-Beer's law in the range 0.2-1.4 μg mL-1of hydrogen sulphide. Molar absorptivity, correlation coefficient and Sandell's sensitivity values were also calculated and found to be 4.2062X103L mol-1cm-1, 0.999 and 0.0012 μg cm-2respectively. The method was employed for the determination of hydrogen sulphide in water samples. The results obtained were reproducible with acceptable standard deviation 0.01-0.068 and relative standard deviation, less than 3.21%. For a comparison, hydrogen sulphide present in water samples were also determined separately following the methylene blue official method. The results of the proposed method compare well with the official method.

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