ÉTUDE DE LA RÉACTION DE L'ADRÉNALINE AVEC L'ÉTHYLÈNEDIAMINE

1959 ◽  
Vol 37 (1) ◽  
pp. 231-244
Author(s):  
Guy Nadeau ◽  
Louis-Philippe Joly
Keyword(s):  
Hydrochloric Acid ◽  
Complex Formation ◽  
Beneficial Effect ◽  
Ultraviolet Light ◽  
Room Temperature ◽  
Aliphatic Alcohols ◽  
Fluorescent Material ◽  
Optimum Ph ◽  
Formation Efficiency ◽  
Influence Of Ph

The influence of pH, reagent composition, time, temperature, light, and various ions, on the reaction of fluorescence between adrenaline and ethylenediamine, has been investigated. The necessity of a preliminary oxidation to adrenochrome is confirmed. Optimum pH of reaction is situated at 10.4 ± 0.1, while extraction with isobutanol is best performed at pH 10.1 ± 0.1. A satisfactory reagent is one that contains 114.5 millimoles of ethylenediamine base per 100 ml of reacting mixture and sufficient hydrochloric acid to bring the pH to 10.3 ± 0.1. Temperature and length of reaction may be conveniently set at 50 °C and 20 to 30 minutes. Increasing the temperature significantly lowers the yield of fluorescent material; performing the reaction at room temperature increases the yield, but lengthens the procedure. Exposure to diffuse and ultraviolet light also affects the yield of fluorescence. All these factors (temperature, light, as well as excess of oxygen) appear to exert their influence in the first stages of the reaction, since the fluorescent material, once formed, is relatively stable. The beneficial effect of various ions, including Cu++, Al+++, and MoO4−−, is discussed in relation to complex formation. Efficiency of extraction with aliphatic alcohols has also been investigated; true yield from C14-adrenaline is estimated. In the light of recent findings on the structure of adrenochrome, new pathways for the reaction are suggested.

ÉTUDE DE LA RÉACTION DE L'ADRÉNALINE AVEC L'ÉTHYLÈNEDIAMINE

1959 ◽  
Vol 37 (2) ◽  
pp. 231-244 ◽  
Author(s):  
Guy Nadeau ◽  
Louis-Philippe Joly
Keyword(s):  
Hydrochloric Acid ◽  
Complex Formation ◽  
Beneficial Effect ◽  
Ultraviolet Light ◽  
Room Temperature ◽  
Aliphatic Alcohols ◽  
Fluorescent Material ◽  
Optimum Ph ◽  
Formation Efficiency ◽  
Influence Of Ph

The influence of pH, reagent composition, time, temperature, light, and various ions, on the reaction of fluorescence between adrenaline and ethylenediamine, has been investigated. The necessity of a preliminary oxidation to adrenochrome is confirmed. Optimum pH of reaction is situated at 10.4 ± 0.1, while extraction with isobutanol is best performed at pH 10.1 ± 0.1. A satisfactory reagent is one that contains 114.5 millimoles of ethylenediamine base per 100 ml of reacting mixture and sufficient hydrochloric acid to bring the pH to 10.3 ± 0.1. Temperature and length of reaction may be conveniently set at 50 °C and 20 to 30 minutes. Increasing the temperature significantly lowers the yield of fluorescent material; performing the reaction at room temperature increases the yield, but lengthens the procedure. Exposure to diffuse and ultraviolet light also affects the yield of fluorescence. All these factors (temperature, light, as well as excess of oxygen) appear to exert their influence in the first stages of the reaction, since the fluorescent material, once formed, is relatively stable. The beneficial effect of various ions, including Cu++, Al+++, and MoO4−−, is discussed in relation to complex formation. Efficiency of extraction with aliphatic alcohols has also been investigated; true yield from C14-adrenaline is estimated. In the light of recent findings on the structure of adrenochrome, new pathways for the reaction are suggested.

Comparative Labelling and Biokinetic Studies of 99mTc-EDTA(Sn) and 99mTc-DTPA(Sn)

1977 ◽  
Vol 16 (01) ◽  
pp. 30-35 ◽  
Author(s):  
N. Agha ◽  
R. B. R. Persson
Keyword(s):  
Complex Formation ◽  
Significant Influence ◽  
Room Temperature ◽  
Ph Value ◽  
Maximum Activity ◽  
Reduction Step ◽  
Labelling Yield ◽  
Different Temperatures ◽  
Kinetics Of

SummaryGelchromatography column scanning has been used to study the fractions of 99mTc-pertechnetate, 99mTcchelate and reduced hydrolyzed 99mTc in preparations of 99mTc-EDTA(Sn) and 99mTc-DTPA(Sn). The labelling yield of 99mTc-EDTA(Sn) chelate was as high as 90—95% when 100 μmol EDTA · H4 and 0.5 (Amol SnCl2 was incubated with 10 ml 99mTceluate for 30—60 min at room temperature. The study of the influence of the pH-value on the fraction of 99mTc-EDTA shows that pH 2.8—2.9 gave the best labelling yield. In a comparative study of the labelling kinetics of 99mTc-EDTA(Sn) and 99mTc- DTPA(Sn) at different temperatures (7, 22 and 37°C), no significant influence on the reduction step was found. The rate constant for complex formation, however, increased more rapidly with increased temperature for 99mTc-DTPA(Sn). At room temperature only a few minutes was required to achieve a high labelling yield with 99mTc-DTPA(Sn) whereas about 60 min was required for 99mTc-EDTA(Sn). Comparative biokinetic studies in rabbits showed that the maximum activity in kidneys is achieved after 12 min with 99mTc-EDTA(Sn) but already after 6 min with 99mTc-DTPA(Sn). The long-term disappearance of 99mTc-DTPA(Sn) from the kidneys is about five times faster than that for 99mTc-EDTA(Sn).

Ultraviolet Light-Densified Oxide-Organic Self-Assembled Dielectrics: Processing Thin-Film Transistors at Room Temperature

2021 ◽  
Vol 13 (2) ◽  
pp. 3445-3453
Author(s):  
Wei Huang ◽  
Xinge Yu ◽  
Li Zeng ◽  
Binghao Wang ◽  
Atsuro Takai ◽  
...  
Keyword(s):  
Thin Film ◽  
Ultraviolet Light ◽  
Thin Film Transistors ◽  
Room Temperature ◽  
Self Assembled

Influence of pH on the kinetics of complex formation between aromatic sulfonamides and human carbonic anhydrase

Biochemistry ◽  
1970 ◽  
Vol 9 (20) ◽  
pp. 3894-3902 ◽  
Author(s):  
Palmer W. Taylor ◽  
Rodney William King ◽  
Arnold S. V. Burgen
Keyword(s):  
Complex Formation ◽  
Carbonic Anhydrase ◽  
Human Carbonic Anhydrase ◽  
Influence Of Ph ◽  
Kinetics Of

scholarly journals Room temperature silylation of alcohols catalyzed by metal organic frameworks

2017 ◽  
Vol 7 (12) ◽  
pp. 2445-2449 ◽  
Author(s):  
Amarajothi Dhakshinamoorthy ◽  
Andrea Santiago-Portillo ◽  
Patricia Concepción ◽  
José R. Herance ◽  
Sergio Navalón ◽  
...  
Keyword(s):  
Heterogeneous Catalyst ◽  
Room Temperature ◽  
Metal Organic Frameworks ◽  
Aliphatic Alcohols ◽  
Benzenedicarboxylic Acid ◽  
Metal Organic

Commercial Al(OH)(BDC) (BDC: 1,4-benzenedicarboxylic acid) is a suitable heterogeneous catalyst for the silylation of benzylic and aliphatic alcohols by hexamethyldisilazane in toluene at room temperature.

Influence of Hydrochloric Acid Concentrations on the Formation of AgCl-Doped Iron Oxide-Silica Coreshell Structures

2012 ◽  
Vol 77 ◽  
pp. 184-189 ◽  
Author(s):  
Norsuria Mahmed ◽  
Oleg Heczko ◽  
Simo Pekka Hannula
Keyword(s):  
Iron Oxide ◽  
Hydrochloric Acid ◽  
Room Temperature ◽  
Silver Chloride ◽  
Ambient Atmosphere ◽  
High Concentration ◽  
Wet Chemistry ◽  
Hcl Concentration ◽  
Average Size ◽  
Very High

Silver chloride (AgCl) nanoparticles with the average size of about 45 nm have successfully been doped onto the iron oxide-silica coreshell surfaces by a simple room temperature wet chemistry method under ambient atmosphere. The Stöber process has been used to make the coreshell structure, followed by adsorption of Ag+ species on silica surface prior to the addition of hydrochloric acid (HCl) and polyvinylpyrrolidone (PVP). The concentration of HCl acid that was used to induce the growth of AgCl particles was varied from 0.12 mM to 12x103 mM of concentrations. Results showed that at a very high concentration of HCl (12x103 mM), large AgCl agglomerates (0.3-0.6 microns) with irregular cubic-like morphology were obtained while at a very low, 12 mM HCl concentration, 30-50nm AgCl particles having a uniform cubic morphology were observed. Concentrations below 12 mM result in irregular and nearly spherical morphology of AgCl particles with a smaller size (28-60 nm). UV-Vis absorption of the composite materials showed absorption in the visible wavelength indicating that Ag nanoclusters might coexist together with AgCl particles.

Studies on Copper Ion Adsorption Using Pectin/Functionalized-Silica Coated Cellulose

2015 ◽  
Vol 1131 ◽  
pp. 210-214
Author(s):  
Radchada Buntem ◽  
Thitiwat Tanyalax
Keyword(s):  
Hydrochloric Acid ◽  
Adsorption Capacity ◽  
Filter Paper ◽  
Copper Ion ◽  
Silica Sol ◽  
Ion Adsorption ◽  
Functionalized Silica ◽  
Solution Ph ◽  
Optimum Ph ◽  
Sem Micrograph

The pectin/functionalized silica coated filter paper (FILPSL2) was used for copper ion adsorption. Silica sol (1), prepared by mixing ethanol, water, TEOS and hydrochloric acid, was slowly added into pectin solution. A piece of filter paper (2 cm x 2 cm) was immersed in the silica-pectin solution for 1 hr. The coated filter paper was dried at room temperature and then oven-dried at 50 °C for 6 hrs to obtain FILPS. The silica sol (2) was subsequently prepared by mixing ethanol, water, N-[3-(Trimethoxysilyl) propyl] ethylenediamine (L2) and hydrochloric acid. The FILPS was immersed in silica sol (2) and the coated paper was oven-dried at 50 °C for 6 hrs to obtain FILPSL2. The SEM micrograph of uncoated Filter paper (FIL) and FILPSL2 showsa characteristic woven pattern. For copper ion adsorption, FILPSL2 was put into 0.1 M of CuCl2solution (pH 2, 25 °C). The color of the paper changes from off-white to intense blue within 5 min due to the complex between amino group of functionalized silica and Cu2+ as evidenced from IR spectroscopy.The equilibrium adsorption percentage and adsorption capacity were 27.10 and 5.5 x 10-3 respectively. The concentrations of copper ion solutions were varied to 10-2and 10-3M at this pH. The lower concentration of copper ion results in the higher adsorption percentage. While the lower concentration of copper ion results in the lower adsorption capacity. The adsorption was also experimented at pH 3.The similar trend was obtained. The optimum pH for adsorption for all concentrations was 2. The effect of interferences on the copper ion adsorption depends on the pH. At pH 2, Ni2+ has a stronger effect. While Cd2+ has a stronger effect at pH 3. The desorption was performed using 0.2 M CH3COOH solution. The complete desorption occurred within 30 min.

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