The Assay of Factor VIII: C in Heparinized Plasma: A Polybrene Neutralization Method

1986 ◽  
Vol 55 (01) ◽  
pp. 058-060 ◽  
Author(s):  
A M Cumming ◽  
R T Wensley ◽  
I W Delamore
Keyword(s):  
Factor Viii ◽  
Ammonium Salt ◽  
Quaternary Ammonium ◽  
Quaternary Ammonium Salt ◽  
Anticoagulant Effect ◽  
Ionized Calcium ◽  
Initial Activity ◽  
One Stage ◽  
Coagulant Activity

SummaryFactor VIII coagulant activity (VIII: C) has been shown by several investigators to exhibit increased stability in vitro when physiological levels of plasma ionized calcium are maintained by anticoagulation with heparin rather than citrate. An increase in initial activity of VIII: C in heparin over that of VIII: C in citrate has been reported but this has not been confirmed. In order to assay VIII :C in heparinized plasma, the heparin anticoagulant effect must be excluded without interfering with the validity of the assay. A one-stage clotting assay for VIII: C has been developed where heparin is neutralized by Polybrene®, a synthetic polymerized quaternary ammonium salt. VIII :C may be accurately measured by this method which satisfies the requirements for a valid assay of parallelism and linearity.

Validation of a Procedure for Potency Assessing of a High Purity Factor VIII Concentrate -Comparison of Different Factor VIII Coagulant Assays and Effect of Prediluent

1990 ◽  
Vol 64 (02) ◽  
pp. 251-255 ◽  
Author(s):  
Claudine Mazurier ◽  
Armelle Parquet-Gernez ◽  
Maurice Goudemand
Keyword(s):  
Factor Viii ◽  
Specific Activity ◽  
Assay Method ◽  
One Stage ◽  
Chromogenic Assay ◽  
Coagulant Activity ◽  
The One ◽  
In Vitro Data

SummaryThe assessment of factor VIII coagulant activity (FVTII: C) in recently available highly purified and concentrated FVTII therapeutic products calls for careful evaluation of assay methodologies. We assayed more than 130 batches of a concentrate with a specific activity of about 150 FVTII :C units/mg protein, using one-stage and two-stage clotting and chromogenic methods. There was good agreement between the potency estimates obtained with the different methods. We also compared the FVTII :C potencies obtained after predilution in buffer or FVIII-deficient plasma using either calibrated plasma or FVTII concentrate as references. With the one-stage assay we found a marked discrepancy between the potency values obtained with buffer and with FVTII-deficient plasma used as prediluents. In order to validate our “in vitro” data we performed 6 “in vivo” analyses in severe haemophilia A patients. On the basis of the overall data obtained we chose to label FVIII potency by using FVIII-deficient plasma as prediluent, reference plasma as standard and the chromogenic assay method.

Synthesis of a Bi-Quaternary Ammonium Salt from Rosin and its Inhibition to some Wood Decay Fungi

2012 ◽  
Vol 174-177 ◽  
pp. 478-482 ◽  
Author(s):  
Thi Thanh Hien Nguyen ◽  
Shu Jun Li ◽  
Jian Li ◽  
Yan Jin ◽  
Nan Xue Liu
Keyword(s):  
Ammonium Chloride ◽  
Ammonium Salt ◽  
Quaternary Ammonium ◽  
Quaternary Ammonium Salt ◽  
Inhibitory Effect ◽  
Gravimetric Analysis ◽  
Irpex Lacteus ◽  
Decay Fungi ◽  
Anti Fungal

An anti-fungal derivative of rosin, bi-quaternary ammonium salt (B-QAS) was synthesized. First, rosin was modified by acrylic acid. Then using this modified rosin reacted with an intermediate quaternary ammonium (epoxy propyl triethyl ammonium chloride) which was the reaction product of triethylamine and epichlorohydrin. The final product was bisN-(3-rosin acyloxy -2-hydroxy) propyl-N, N triethyl ammonium chloride. The chemical structure of the product and its functional groups was characterized by Fourier transform infrared spectroscopy (FTIR). Its yield of greater than 80% was conformed by high performance liquid chromatography (HPLC) and gravimetric analysis. Its anti-fungal activity was determined in vitro with a paper-disc method. B-QAS presented significant inhibitory effect for Trametes versicolor, Gloeophyllum trabeum and Postia placenta when its concentration was 0.5 mg/mL, whereas for Irpex lacteus the inhibitory effect was a little poor.

Catalyst- and oxidant-free electrochemical para-selective hydroxylation of N-arylamides in batch and continuous-flow

2020 ◽  
Vol 22 (19) ◽  
pp. 6437-6443
Author(s):  
Cheng-Kou Liu ◽  
Meng-Yi Chen ◽  
Xin-Xin Lin ◽  
Zheng Fang ◽  
Kai Guo
Keyword(s):  
Ammonium Salt ◽  
Quaternary Ammonium ◽  
Continuous Flow ◽  
Quaternary Ammonium Salt ◽  
Selective Hydroxylation

A catalyst-, oxidant-, acidic solvent- and quaternary ammonium salt-free electrochemical para-selective hydroxylation of N-arylamides at rt in batch and continuous-flow was developed.

Synthesis and Performance of Polyoxy-ethylene Ester Quaternary Ammonium Salt

2013 ◽  
Vol 50 (1) ◽  
pp. 9-13 ◽  
Author(s):  
Yong-Qiang Sun ◽  
Wen-Jing Li ◽  
Wan-Xu Wang ◽  
Qiu-Xiao Li ◽  
Wieslaw Hreczuch ◽  
...  
Keyword(s):  
Ammonium Salt ◽  
Quaternary Ammonium ◽  
Quaternary Ammonium Salt ◽  
And Performance

Instability of Solutions of Quaternary Ammonium Permanganates in Dichloromethane

1997 ◽  
Vol 62 (6) ◽  
pp. 849-854 ◽  
Author(s):  
Vladislav Holba ◽  
Renata Košická
Keyword(s):  
Ammonium Salt ◽  
Rate Constants ◽  
Quaternary Ammonium ◽  
Quaternary Ammonium Salt ◽  
Activation Parameters ◽  
The Stability

The paper deals with instability of solutions of quaternary ammonium permanganates, QMnO4 (Q = tetraethyl-, tetra-1-propyl-, tetra-1-butyl-, tetra-1-pentyl-, tetra-1-octyl-, and cetyltrimethylammonium), in dichloromethane and presents the rate constants and activation parameters of the reduction of permanganate. Attention was paid to the properties of colloidal Mn(IV) intermediate. The stability of the solutions depends markedly on the quaternary ammonium salt used.

Systematic exploration of quaternary ammonium salt adsorption on oxidized coal based on experiments and MD simulations

Fuel ◽  
2021 ◽  
Vol 287 ◽  
pp. 119434
Author(s):  
Jun Chen ◽  
Hongliang Li ◽  
Chunfu Liu ◽  
Lingyun Liu ◽  
Yu Sun ◽  
...  
Keyword(s):  
Ammonium Salt ◽  
Quaternary Ammonium ◽  
Quaternary Ammonium Salt ◽  
Md Simulations ◽  
Oxidized Coal ◽  
Systematic Exploration

scholarly journals Antibacterial performance of polymer quaternary ammonium salt–capped silver nanoparticles on Bacillus subtilis in water

RSC Advances ◽  
2019 ◽  
Vol 9 (44) ◽  
pp. 25667-25676 ◽  
Author(s):  
Jingyu Wang ◽  
Minghao Sui ◽  
Zhanfang Ma ◽  
Hongwei Li ◽  
Bojie Yuan
Keyword(s):  
Silver Nanoparticles ◽  
Bacillus Subtilis ◽  
Ammonium Salt ◽  
Quaternary Ammonium ◽  
Quaternary Ammonium Salt ◽  
Antibacterial Performance ◽  
Antibacterial Capacity

Polymer quaternary ammonium salt–capped silver nanoparticles (PQAS–AgNPs) were synthesized, and they exhibited significant antibacterial capacity against Bacillus subtilis.

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