The Determination of Cholinestcrase Activity in Blood Samples Absorbed on Filter Paper

1954 ◽  
Vol 30 (1) ◽  
pp. 45-54 ◽  
Author(s):  
KLAS-BERTIL AUGUSTINSSON ◽  
GUNILLA HEIMBÜRGER
Keyword(s):  
1985 ◽  
Vol 31 (5) ◽  
pp. 750-753 ◽  
Author(s):  
N Hata ◽  
K Miyai ◽  
M Ito ◽  
Y Endo ◽  
Y Iijimi ◽  
...  

Abstract We describe a double-antibody enzyme immunoassay for determination of free thyroxin (FT4) in dried blood samples on filter paper, with use of a T4-beta-D-galactosidase complex. The measurable range of FT4 concentration in two 3-mm blood discs, each of which contained about 2.7 microL of blood, was 1.9 to 93 ng/L, as determined by comparison with concentrations of FT4 in known serum standards. FT4 in blood samples dried on filter paper was stable for at least four weeks when kept dry at -20 degrees C, room temperature, or 37 degrees C. The mean coefficients of variation were 7.6% (within assay) and 6.4% (between assays). Results for FT4 by this method correlated well with those for serum determined by radioimmunoassay (r = 0.98). The proposed method can be used to differentiate persons with hyper- and hypothyroidism from normal subjects and those with abnormal concentrations of thyroxin-binding globulin. The procedure seems suited for screening studies.


Toxicon ◽  
2001 ◽  
Vol 39 (10) ◽  
pp. 1607-1609 ◽  
Author(s):  
Wany S. Maria ◽  
Bruno G. Pacheco ◽  
Célia F. Barbosa ◽  
David T. Velarde ◽  
Carlos Chávez-Olórtegui
Keyword(s):  

1983 ◽  
Vol 29 (7) ◽  
pp. 1437-1440 ◽  
Author(s):  
N Hata ◽  
M Ito ◽  
H Mizuta ◽  
O Nose ◽  
K Miyai

Abstract A double-antibody enzyme immunoassay was developed for determination of thyroxin-binding globulin in dried blood samples on filter paper. The measurable concentration range of thyroxin-binding globulin in two 3-mm blood discs was 3.3 to 52 mg/L equivalent of serum (i.e., equivalent to the concentrations in known serum standards). Thyroxin-binding globulin in dried blood samples on filter paper was stable for at least four weeks when kept dry at -20 degrees C, 4 degrees C, or room temperature. The mean coefficients of variation were 6.6% (within assay) and 5.9% (between assays). The concentrations of thyroxin-binding globulin in dried blood samples determined by this method correlated well with those in serum determined by radioimmunoassay (r = 0.95) and by enzyme immunoassay (r = 0.96). This method is applicable for detecting cases of thyroxin-binding globulin deficiency and avoids the false-positive results for neonatal hypothyroidism obtained by measuring thyroxin.


2016 ◽  
Vol 5 (10) ◽  
pp. 4920
Author(s):  
Amar M. Ali ◽  
Hussain. J. Mohammed*

A new, simple, sensitive and rapid spectrophotometric method is proposed for the determination of trace amount of Nickel (II). The method is based on the formation of a 1:2 complex with 4-(4-((2-hydroxy-6-nitrophenyl) diazenyl) -3-methyl-5-oxo-2, 5-dihydro-1H-pyrazol-1-yl) benzenesulfonic acid (2-ANASP) as a new reagent is developed. The complex has a maximum absorption at 516 nm and εmax of 1. 84 X 105 L. mol-1. cm-1. A linear correlation (0. 25 – 4. 0μg. ml-1) was found between absorbance at λmax and concentration. The accuracy and reproducibility of the determination method for various known amounts of Nickel (II) were tested. The results obtained are both precise (RSD was 1. 2 %) and accurate (relative error was 0. 787 %). The effect of diverse ions on the determination of Nickel (II) to investigate the selectivity of the method were also studied. The stability constant of the product was 0. 399 X 106 L. mol-1. The proposed method was successfully applied to the analysis of diabetes blood and normal human blood. 


Separations ◽  
2021 ◽  
Vol 8 (6) ◽  
pp. 78
Author(s):  
Sevasti Karampela ◽  
Jessica Smith ◽  
Irene Panderi

An ever-increasing need exists within the forensic laboratories to develop analytical processes for the qualitative and quantitative determination of a broad spectrum of new psychoactive substances. Phenylethylamine derivatives are among the major classes of psychoactive substances available on the global market and include both amphetamine analogues and synthetic cathinones. In this work, an ultra-high-performance liquid chromatography-positive ion electrospray ionization tandem mass spectrometric method (UHPLC-ESI-MS/MS) has been developed and fully validated for the determination of 19 psychoactive substances, including nine amphetamine-type stimulants and 10 synthetic cathinone derivatives, in premortem and postmortem whole blood. The assay was based on the use of 1 mL premortem or postmortem whole blood, following solid phase extraction prior to the analysis. The separation was achieved on a Poroshell 120 EC-C18 analytical column with a gradient mobile phase of 0.1% formic acid in acetonitrile and 0.1% formic acid in water in 9 min. The dynamic multiple reaction monitoring used in this work allowed for limit of detection (LOD) and lower limit of quantitation (LOQ) values of 0.5 and 2 ng mL−1, respectively, for all analytes both in premortem and postmortem whole blood samples. A quadratic calibration model was used for the 12 quantitative analytes over the concentration range of 20–2000 ng mL−1, and the method was shown to be precise and accurate both in premortem and postmortem whole blood. The method was applied to the analysis of real cases and proved to be a valuable tool in forensic and clinical toxicology.


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