scholarly journals Degradation dynamics and dissipation kinetics of an imidazole fungicide (Prochloraz) in aqueous medium of varying pH

2008 ◽  
Vol 1 (3-4) ◽  
pp. 203-205 ◽  
Author(s):  
Md. Aktar ◽  
Dwaipayan Sengupta ◽  
Swarnali Purkait ◽  
Madhumita Ganguly ◽  
M. Paramasivam
Keyword(s):  
Aqueous Medium ◽  
Water Samples ◽  
Half Life ◽  
Residue Analysis ◽  
Uv Detector ◽  
Dissipation Kinetics ◽  
Degradation Studies ◽  
Kinetics Of

Degradation dynamics and dissipation kinetics of an imidazole fungicide (Prochloraz) in aqueous medium of varying pHLaboratory degradation studies were performed in water at pH 4.0, 7.0 and 9.2 using Prochloraz (450 EC) formulation at the concentration of 1.0 (T1) and 2.0 (T2) μg/mL. Water samples collected on 0 (2 h), 3, 7, 15, 30, 45, 60 and 90 days after treatments were processed for residue analysis of Prochloraz by HPLC-UV detector. In 60 days, dissipation was 89.1-90.5% at pH 4.0, 84.1-88.2% at pH 7.0, and 92.4-93.8% at pH 9.2 in both treatments. The results indicate that at pH 7.0 the degradation of Prochloraz was much slower as compared to other two. Between pH 4.0 and 9.2 the degradation of compound is little faster at pH 9.2. The half-life periods observed were 18.35 and 19.17 days at pH 4.0, 22.6 and 25.1 days at pH 7.0 and 15.8 and 16.6 days at pH 9.2 at T1and T2doses respectively.

scholarly journals A Liquid Chromatographic Method for Determination of Acetamiprid and Buprofezin Residues and Their Dissipation Kinetics in Paddy Matrices and Soil

2021 ◽  
Author(s):  
Sujan Majumder ◽  
Somnath Mandal ◽  
Biswajit Majumder ◽  
Anindita Paul ◽  
Tarun Paul ◽  
...  
Keyword(s):  
Chromatographic Method ◽  
Residue Analysis ◽  
Double Dose ◽  
Uv Detector ◽  
Limit Of Quantification ◽  
Dissipation Kinetics ◽  
Assessment Study ◽  
Liquid Chromatographic Method ◽  
Liquid Chromatographic

Abstract The present study was conducted to investigate the residue status of two insecticides (acetamiprid and buprofezin) and their dissipation kinetics in three matrices viz. paddy grain, straw and soil. The extraction protocol for residues of these two insecticides was executed using acetonitrile solvent. The analytical method was validated, which showed good linearity with the limit of quantification (LOQ) value of 0.01 and 0.02 mg kg-1 for acetamiprid and buprofezin respectively. The recovery range was 79.67-98.33 % concerning all the matrices in both the insecticides. Acetamiprid (20% SP) and Buprofezin (25% SC) were applied separately in the paddy field in two doses: single dose (recommended dose) and double dose along with untreated control throughout the experiment. Residue analysis of these two insecticides in paddy (grain and straw) and soil was accomplished employing high-pressure liquid chromatography (HPLC) with a UV detector. The dissipation data showed that acetamiprid exhibited higher dissipation in comparison with buprofezin. However, their persistence was found slightly higher in soil. The dissipation dynamics in the rice and soil were discussed with biological half-lives of both the insecticides. Consumer risk assessment study was also made considering its fate to the consumers.

scholarly journals A Liquid Chromatographic Method for Determination of Acetamiprid and Buprofezin Residues and Their Dissipation Kinetics in Paddy Matrices and Soil

2021 ◽  
Author(s):  
Sujan Majumder ◽  
Somnath Mandal ◽  
Biswajit Majumder ◽  
Anindita Paul ◽  
Tarun Paul ◽  
...  
Keyword(s):  
Chromatographic Method ◽  
Residue Analysis ◽  
Double Dose ◽  
Uv Detector ◽  
Limit Of Quantification ◽  
Dissipation Kinetics ◽  
Assessment Study ◽  
Liquid Chromatographic Method ◽  
Liquid Chromatographic

Abstract The present study was conducted to investigate the residue status of two insecticides (acetamiprid and buprofezin) and their dissipation kinetics in three matrices viz. paddy grain, straw and soil. The extraction protocol for residues of these two insecticides was executed using acetonitrile solvent. The analytical method was validated, which showed good linearity with the limit of quantification (LOQ) value of 0.01 and 0.02 mg kg− 1 for acetamiprid and buprofezin respectively. The recovery range was 79.67–98.33 % concerning all the matrices in both the insecticides. Acetamiprid (20% SP) and Buprofezin (25% SC) were applied separately in the paddy field in two doses: single dose (recommended dose) and double dose along with untreated control throughout the experiment. Residue analysis of these two insecticides in paddy (grain and straw) and soil was accomplished employing high-pressure liquid chromatography (HPLC) with a UV detector. The dissipation data showed that acetamiprid exhibited higher dissipation in comparison with buprofezin. However, their persistence was found slightly higher in soil. The dissipation dynamics in the rice and soil were discussed with biological half-lives of both the insecticides. Consumer risk assessment study was also made considering its fate to the consumers.

Kinetics of Various 99mTc-Sn-Pyrophosphate Compounds in the Rat

1977 ◽  
Vol 16 (04) ◽  
pp. 157-162 ◽  
Author(s):  
C. Schümichen ◽  
B. Mackenbrock ◽  
G. Hoffmann
Keyword(s):  
Normal Saline ◽  
Half Life ◽  
Compound A ◽  
Short Half Life ◽  
Low Concentrations ◽  
The Stability ◽  
Kinetics Of ◽  
In Vitro Stability

SummaryThe bone-seeking 99mTc-Sn-pyrophosphate compound (compound A) was diluted both in vitro and in vivo and proved to be unstable both in vitro and in vivo. However, stability was much better in vivo than in vitro and thus the in vitro stability of compound A after dilution in various mediums could be followed up by a consecutive evaluation of the in vivo distribution in the rat. After dilution in neutral normal saline compound A is metastable and after a short half-life it is transformed into the other 99mTc-Sn-pyrophosphate compound A is metastable and after a short half-life in bone but in the kidneys. After dilution in normal saline of low pH and in buffering solutions the stability of compound A is increased. In human plasma compound A is relatively stable but not in plasma water. When compound B is formed in a buffering solution, uptake in the kidneys and excretion in urine is lowered and blood concentration increased.It is assumed that the association of protons to compound A will increase its stability at low concentrations while that to compound B will lead to a strong protein bond in plasma. It is concluded that compound A will not be stable in vivo because of a lack of stability in the extravascular space, and that the protein bond in plasma will be a measure of its in vivo stability.

Persistence and Dissipation Kinetics of Deltamethrin on Chili in Different Agro-Climatic Zones of India

2012 ◽  
Vol 88 (5) ◽  
pp. 764-768 ◽  
Author(s):  
Suneet Pandher ◽  
S. K. Sahoo ◽  
R. S. Battu ◽  
Balwinder Singh ◽  
M. S. Saiyad ◽  
...  
Keyword(s):  
Climatic Zones ◽  
Dissipation Kinetics ◽  
Kinetics Of

Dissipation Kinetics of Flubendiamide on Chili and Soil

2009 ◽  
Vol 83 (3) ◽  
pp. 384-387 ◽  
Author(s):  
S. K. Sahoo ◽  
R. K. Sharma ◽  
R. S. Battu ◽  
Balwinder Singh
Keyword(s):  
Dissipation Kinetics ◽  
Kinetics Of

scholarly journals METHOD DEVELOPMENT AND VALIDATION FOR THE ESTIMATION OF ENTECAVIR IN BULK AND PHARMACEUTICAL DOSAGE FORMS BY RP-HPLC

2017 ◽  
pp. 107-111
Author(s):  
Swathi P. ◽  
S. Vidyadhara ◽  
R. L. C. Sasidhar ◽  
K. Kalyan Chakravarthi
Keyword(s):  
Flow Rate ◽  
Dosage Forms ◽  
Hplc Method ◽  
Forced Degradation ◽  
Uv Detector ◽  
Pharmaceutical Dosage Form ◽  
Pharmaceutical Dosage Forms ◽  
Rp Hplc ◽  
Validation Parameters ◽  
Degradation Studies

Objective: The objective and purpose of the analysis have sensibly assessed by selecting of a rapid and sensitive RP-HPLC method for Entecavir in bulk and pharmaceutical dosage form by using the most commonly employed C-18column with UV detection.Methods: In estimation by RP-HPLC method Agilent 1120 compact LC system with variable programmable UV detector and Rheodyne injector with 20 µl fixed loop was used for the chromatographic separation. The mode of operation was isocratic with the components of a solution consisting of methanol: acetonitrile(70:30v/v) and triethanolamine (2-4drops)at the flow rate of 1.2 ml/min and run time was 10 min. Forced degradation studies were conducted to evaluate the stability and specificity of the method along with the validation parameters.Results: Validation parameters of HPLC were found at a detection wavelength of 255 nm. Linearity was observed with the concentration range (Beer’s law range) 20-100µg/ml with R2=0.9991. Robustness with detection wavelengths 253 and 257 nm with a flow rate of 1 ml/min and 1.4 ml/min showed good results. The retention time of the drug was 2.64 min and assay showed 98.1%.Conclusion: The proposed RP-HPLC method was validated as per the ICH Q2B Guidelines, and was found to be applicable for routine quantitative analysis of Entecavir by RP-HPLC using UV detector in pharmaceutical dosage forms. The results of linearity, precision, accuracy and specificity, were proved, that does not exceed certain specified limits. The method provides selective quantification with no interference from other formulation excipients. The proposed method was highly sensitive, reproducible, reliable, robust and specific. Therefore, this method is a simple, rapid analysis may actually be more desirable than a more complicated and time-consuming process. The degradation studies at various stress conditions like thermal and hydrolytic, drug gets degraded at a temperature of 80 °c and refluxing with water at 70 °c for 24hours. 

Sign in / Sign up

Export Citation Format

Share Document