A rapid and sensitive colorimetric method for the detection of cyanide ions in aqueous samples

2021 ◽  
Vol 24 ◽  
pp. 101973
Author(s):  
Pawankumar Rai ◽  
Srishti Mehrotra ◽  
Abhay Raj ◽  
Sandeep K. Sharma
Keyword(s):  
Colorimetric Method ◽  
Aqueous Samples

A colorimetric method for fluoride determination in aqueous samples based on the hydroxyl deprotection reaction of a cyanine dye

2005 ◽  
Vol 539 (1-2) ◽  
pp. 311-316 ◽  
Author(s):  
Chang-Qing Zhu ◽  
Jin-Long Chen ◽  
Hong Zheng ◽  
Yu-Qin Wu ◽  
Jin-Gou Xu
Keyword(s):  
Colorimetric Method ◽  
Cyanine Dye ◽  
Aqueous Samples ◽  
Fluoride Determination

scholarly journals Endpoint Colorimetric Method for Assaying Total Cholesterol in Serum with Cholesterol Dehydrogenase

1999 ◽  
Vol 45 (12) ◽  
pp. 2158-2163 ◽  
Author(s):  
Yuzo Kayamori ◽  
Hiroyuki Hatsuyama ◽  
Tadayoshi Tsujioka ◽  
Masato Nasu ◽  
Yoshiaki Katayama
Keyword(s):  
Serum Cholesterol ◽  
Free Cholesterol ◽  
Cholesterol Oxidase ◽  
Colorimetric Method ◽  
Aqueous Samples ◽  
Absorbance Change ◽  
The Mean ◽  
Reducing Substances ◽  
Endpoint Assay ◽  
Kendall Method

Abstract Background: Various methods are available to measure serum cholesterol concentrations. Of these, the cholesterol ester hydrolase (CEH)-cholesterol oxidase-peroxidase chromogenic method is widely used. However, this method has the disadvantage of interference by reducing substances. We developed and evaluated an endpoint assay for serum cholesterol, based on a CEH-cholesterol dehydrogenase (CDH)-ultraviolet method. Methods: Cholesterol esters are first hydrolyzed to free cholesterol by CEH. The free cholesterol is then reduced by CDH to cholest-4-ene-3-one with the simultaneous production of β-NADH from β-NAD+. At equilibrium, the CDH reaction gives incomplete conversion of cholesterol to cholest-4-ene-3-one. To overcome this disadvantage, we added hydrazine monohydrate to the reaction mixture to remove cholest-4-ene-3-one, which allowed the reaction to proceed to completion and gave stoichiometric production of β-NADH from the reaction of β-NAD+ with cholesterol. Results: We tested whether the amount of cholesterol added was equivalent to the absorbance change of NADH at 340 nm with six aqueous samples. Recoveries were 97.1–100.3%. The reaction was linear up to 20.28 mmol/L. The mean within-day (n = 20) and between-day (n = 10) imprecision (CV) was 0.29–0.43% and 0.22–0.61%, respectively. No interference by bilirubin, hemoglobin, ascorbic acid, and other reducing agents was observed. The equation obtained in comparison with the modified Abell-Levy-Brodie-Kendall method was: y = 0.992x − 0.0058 mmol/L; r = 0.997; Sy|x = 0.117 mmol/L; n = 50. Conclusion: This method is an accurate, reliable method for serum cholesterol analysis and is amenable to automation.

Preliminary study on removal of nitrate nitrogen in aqueous samples by microbial nano-silica ball

2014 ◽  
Author(s):  
Jia Lu ◽  
Xiaohou Shao ◽  
Chao Yin ◽  
Xinyu Mao ◽  
Long Wang ◽  
...  
Keyword(s):  
Nitrate Nitrogen ◽  
Aqueous Samples ◽  
Nano Silica ◽  
Preliminary Study

The Reference Intervals Used in Pediatric Medical Analysis Laboratories to Interpret the Results Analysis for Total Serum Calcium

2017 ◽  
Vol 68 (2) ◽  
pp. 243-245
Author(s):  
Elisabeta Antonescu ◽  
Maria Totan ◽  
Gheorghe Cornel Boitor ◽  
Julianna Szakacs ◽  
Sinziana Calina Silisteanu ◽  
...  
Keyword(s):  
Serum Calcium ◽  
Colorimetric Method ◽  
Age Groups ◽  
Essential Element ◽  
Reference Intervals ◽  
Total Serum ◽  
Electronic Archive ◽  
Total Serum Calcium ◽  
Analysis Laboratory ◽  
Medical Analysis

Medical analysis laboratory must establish its own reference intervals depending on the facilities they are working with, the working substances and protocols. These reference intervals must be obtained depending on age groups in order to accurately interpret the results of the analyzes performed. The study is a retrospective one using 3217 data from the electronic archive of the S.C. Vladutiu&Garabedian S.R.L. Clinic in Medias. Total serum calcium was determined by the colorimetric method on the Konelab analyzer. Processing of the collected data was done using the Hoffmann method, considering 5% up to 95% of the values in the database, the values being randomly selected. For comparison, data from the literature was used. In children under 1 year old, it was not possible to calculate the reference intervals since data was insufficient. In the other age groups, reference intervals obtained in the current study were similar to the studied literature. Reference intervals established for calcium can provide important guidance for the reasonable supplementation of this essential element in children.

Development of Synchrotron Footprinting at NSLS and NSLS-II

2019 ◽  
Vol 26 (1) ◽  
pp. 55-60 ◽  
Author(s):  
Jen Bohon
Keyword(s):  
Solvent Accessibility ◽  
Biological Systems ◽  
In Vivo Studies ◽  
Aqueous Samples ◽  
Biological Mechanisms ◽  
Macromolecular Assembly ◽  
Structure And Dynamics ◽  
Synchrotron Light ◽  
Ideal Technique

Background: First developed in the 1990’s at the National Synchrotron Light Source, xray synchrotron footprinting is an ideal technique for the analysis of solution-state structure and dynamics of macromolecules. Hydroxyl radicals generated in aqueous samples by intense x-ray beams serve as fine probes of solvent accessibility, rapidly and irreversibly reacting with solvent exposed residues to provide a “snapshot” of the sample state at the time of exposure. Over the last few decades, improvements in instrumentation to expand the technology have continuously pushed the boundaries of biological systems that can be studied using the technique. Conclusion: Dedicated synchrotron beamlines provide important resources for examining fundamental biological mechanisms of folding, ligand binding, catalysis, transcription, translation, and macromolecular assembly. The legacy of synchrotron footprinting at NSLS has led to significant improvement in our understanding of many biological systems, from identifying key structural components in enzymes and transporters to in vivo studies of ribosome assembly. This work continues at the XFP (17-BM) beamline at NSLS-II and facilities at ALS, which are currently accepting proposals for use.

Creatinuria and Dynamics of Calcium Metabolism in Children in the Phase of Exacerbation of Bronchial Asthma

2020 ◽  
Vol 16 (1) ◽  
pp. 28-33
Author(s):  
Vitalii B. Kaliberdenko ◽  
Shanmugaraj Kulanthaivel ◽  
Michael V. Shterenshis ◽  
Olga Y. Poleshchuk ◽  
Kadri Mametov ◽  
...  
Keyword(s):  
Creatine Kinase ◽  
Blood Serum ◽  
Bronchial Asthma ◽  
Picric Acid ◽  
Colorimetric Method ◽  
Cellular Level ◽  
Creatine Kinase Activity ◽  
Biological Medium ◽  
Creatinine Concentration ◽  
Test Kit

: Bronchial asthma is one of the most common and severe diseases among children. The phenomenon of creatinuria (CU) in patients with bronchial asthma (BA) has been acknowledged for a relatively long time. Aims: The Aim of the research is to study the level of creatinuria, creatinemia, creatine kinase activity, and the concentration of calcium in biological medium (blood, saliva, urine) in children suffering from an intermittent and persistent form of asthma during the period of exacerbation. Material and methods:: The research consists of 102 children with asthma who were treated in inpatient department in Simferopol Clinic. The intermittent course of asthma was recorded in 49 children and a persistent course of asthma was recorded in 53 children. The subject of study was blood serum and daily urine of observed patients. The level of calcium in the biological medium was studied using the "Filisit" test kit (Dnipro) and the activity of the creatine kinase by test set "Lahma". The levels of creatine and creatinine were determined using a colorimetric method based on a color reaction with picric acid. Results and conclusion: : The analysis testifies that creatinuria in children with persistent BA is caused by the disorder of the phosphorylation process rather than the disorder of creatinin rephosphorylation synthesis, that is testified by the normal creatinine level. In children with persistent BA, there is а decrease of creatinine concentration in the blood serum and urine during the exacerbation period and early post exacerbation period. The low activity of creatinine kinase at the background of creatinine elimination is typical for the children in the phase of exacerbation of persistent form of BA, though its level remains to be sufficient for the synthesis of the necessary amount of creatinine phosphate. Conclusion: The processes of creatinuria and calciuria in children suffering from a persistent form of BA are interdependent, that is testified by the data of correlative analysis. In connection with this, it is possible to consider the change of calcium homeostasis in the pathogenesis of the disease as one of the causes of distributing the creatinine metabolism on the cellular level.

Novel palladium(II) selective membrane electrode based on 4-[(5-mercapto-1,3,4-thiadiazol-2-ylimino)methyl]benzene-1,3-diol

2010 ◽  
Vol 75 (5) ◽  
pp. 563-575 ◽  
Author(s):  
Moslem Mohammadi ◽  
Mehdi Khodadadian ◽  
Mohammad K. Rofouei
Keyword(s):  
Limit Of Detection ◽  
Membrane Electrode ◽  
Aqueous Samples ◽  
Selective Determination ◽  
Poly Vinyl Chloride ◽  
Selective Membrane ◽  
Ph Range ◽  
Palladium Content ◽  
Methyl Benzene

A plasticized poly(vinyl chloride) membrane electrode based on 4-[(5-mercapto-1,3,4-thiadiazol-2-ylimino)methyl]benzene-1,3-diol (L) for highly selective determination of palladium(II) (in PdCl42– form) is developed. The electrode showed a good Nernstian response (29.6 ± 0.4 mV per decade) over a wide concentration range (3.1 × 10–7 to 1.0 × 10–2 mol l–1). The limit of detection was 1.5 × 10–7 mol l–1. The electrode has a response time of about 20 s, and it can be used for at least 2 months without observing any considerable deviation from Nernstian response. The proposed electrode could be used in the pH range of 2.5–5.5. The practical utility of the electrode has been demonstrated by its use for the estimation of palladium content in aqueous samples.

Sign in / Sign up

Export Citation Format

Share Document