Cobalt thiocyanates

Lemli and Knockaert [33] described a spectrophotometric method for the determination of miconazole nitrate suspensions and other organic bases in pharmaceutical preparations by the use of cobalt thiocyanate. The drug and the amines (as their anhydrous hydrochlorides in dichloromethane) react with solid cobalt thiocyanate to form an ion-pair complex that contains two molecules of base to one [Co(SCN)4]2. The complex is determined quantitatively by spectrophotometry versus dichloromethane at 625 nm with rectilinear response for up to 400 pg/mL of the base. This method was applied to miconazole nitrate suspensions and the coefficient of variations were generally <2%. 

Cocaine drug testing kits either manufactured for law enforcement purposes or produced by the underground. These testing kits are simply presumptive color tests. The basic color test used for cocaine is cobalt thiocyanate. The cocaine or any of the other substances from the caine family will form a brilliant blue flaky precipitate in the cobalt thiocyanate. This is an indication that the product is cocaine, procaine, tetracaine, etc. In order to determine whether there is actually any cocaine and not all procaine, stannous chloride is added to the precipitate causing all of the caines except cocaine to dissolve. 

ABS AE AE/P AES AG AOS APEO APG AS BiAS BM c6(EO)3 CNPEC CTAS D DATS DCPEG DEEDMAC branched alkylbenzene sulfonate alcohol ethoxylate alcohol ethoxylate/propoxylate alkylether sulfate alkyl glucamide a-olefin sulfonate alkylphenol ethoxylate alkyl polyglucoside alkyl sulfate bismuth active substances alkyldimethylbenzyl ammonium triethylene glycol monohexyl ether carboxylated nonylphenoxy carboxylates cobalt thiocyanate active substances R2S10(o.5)2 dialkyl tetralinsulfonate dicarboxylated PEG ditallow ester of di(hydroxyethyl)dimethyl ammonium chloride... 

Inorganic extractions seem to have come into practical use without any great notice. Although Peligot in 1842 reported that uranyl nitrate could be recrystalhzed from ether, he never mentioned extraction of this salt from aqueous solutions. In textbooks after 1870, however, it is stated briefly that ether can even withdraw sublimate (HgCy from aqueous solution. It was also reported, for example, that cobalt thiocyanate is weakly extracted by ether, better by amyl alcohol, and even better by a mixture of both. 

ERH may be estimated by measuring the relative humidity of the headspace over a food in a small, sealed container hygrometrically, psychro-metrically or directly by measuring the moisture content of the air by gas chromatography. ERH can be estimated by moisture-related colour changes in paper impregnated with cobalt thiocyanate (Co(SCN)2) and compared to standards of known aw. 

If the ratio be unity, the concentrations of the solute in each solvent will be the same if the ratio be far removed from unity, a correspondingly large proportion of the solute will be found in the one solvent which can be utilized to extract the Soln. from the other solvent. E.g. ether will remove ferric chloride from its aq. soln., and since many other chlorides are almost insoluble in ether, the process is utilized in analysis for the separation of iron from the other elements the solubility of cobalt thiocyanate in ether is utilized for the separation of cobalt perchromic acid is similarly separated from its aq. soln. by ether molten zinc extracts silver and gold from molten lead the extraction of organic compounds from aq. soln. by shaking out with ether or other solvent is much used in organic laboratories. 

The biodegradabilities were followed by three analytical methods, i.e. (A) foam height method, (B) cobalt thiocyanate colorimetry (CTAS) and (C) COD (Cr) method. 

The apparatus used is the same as that adopted by Conway et al(13). The test was conducted over long periods at higher concentration of surfactants than in any previous studies. In the test, biodegradation was followed by measuring COD(Cr), COD(Mn), cobalt thiocyanate active substances (CTAS) and TOC(Figure 16). 

Colorimetric Methods have frequently been suggested,1 but of these, that originated by Skey and studied by several others 2 appears to be the most useful. It hinges on the fact that potassium thiocyanate yields a blue colour with solutions of cobalt salts, due to the formation of cobalt thiocyanate. On adding alcohol and ether to the liquid, a blue layer is produced. This is destroyed by mercuric chloride, sodium acetate, or sodium thiosulphate, and is masked by the presence of iron salts in consequence of the intense red colour of ferric thiocyanate consequently these substances should not be present when the colorimetric test is applied. 

Cobalt thiocyanate solution. Blue spots are given by quaternary ammonium compounds. 

Cobalt thiocyanate solution, 1169 Cobmnin, 496 Co-Betaloc, 663, 779 Cobutolin, 963 Coca, 489 Coca leaves, 385 Cocaine, 29, 489 Cocaine hydrochloride, 489 Cocainium chloride, 489 Co-Caps Penicillin V-K, 888 Cocculin, 902 Codeine, 29, 490, 525 -Codeine, 803 Codeine hydrochloride, 490 Codeine jV-oxide, xvii Codeine phosphate, 490 Codeine sulfate, 490 Codeine sulphate, 490 Codelcortone, 917 Codelcortone TBA, 918 Codelsol,918... 

Complexes between phenothiazines and cobalt thiocyanate and with some ingredients in the pharmaceutical preparations were also reported. 

After finishing my research on cobalt thiocyanate in Leipzig I wrote to Werner, asking for a place in his laboratory. In his own hand he replied, should like to inform you that I would be happy to have you work with me. At present there is so much of interest to investigate here that a topic will certainly be found that will give you special pleasure. ... 

A colorimetric method is available which allows the estimation of diltiazem alone and in solid dosage forms. The method involves the reaction of diltiazem with cobalt thiocyanate in acidic media. The complex is extracted in benzene and monitored at 630 nm (33). 

The exploitation of a mini-chamber is the essence of the flow-batch system (5.5.3), and hence the implementation of LLE in this system is best accomplished with this device. This was demonstrated in the spectro-photometric determination of cocaine relying on the formation of a cocaine—cobalt thiocyanate complex and extraction into chloroform [191]. The solutions involved were inserted into a reaction chamber and an optical fibre allowed absorbance measurements without the need for phase separation. Good analytical figures of merit were reported. 

Fluorescence microscopy shows the location of lignin in the cell walls (i4). This technique was developed as a method for determining PEG penetration. The presence of PEG inhibits the fluorescence of the lignin when the tissue is reacted with cobalt thiocyanate (15). 

Recent contributions to the analytical chemistry of this group include an improved determination of total belladonna alkaloids, expressed as hyoscyamine content, based on a simple extraction and titration procedure. A method for the estimation of hyoscine and hyoscyamine utilizes u.v. spectrophotometric determination of the alkaloids following t.l.c. separation.Another method involves the spectrophotometric determination of cobalt thiocyanate complexes, e.g. of n-butylscopolammonium bromide.Further procedures based on column, t.l.c.,g.l.c., or paper chromatographic separation, have been reported. 

Analytical chemists have developed simple chemical tests that can identify the presence of illegal drugs within seconds. Law enforcement officers routinely use these when they are unsure whether someone is in possession of an illegal narcotic. A common field test for cocaine, for example, uses a cobalt thiocyanate complex that turns blue in the presence of cocaine. 

Scott s test (cobalt thiocyanate test Ruybal test) A presumptive test for cocaine. Scott s reagent has an initial solution of 2% cobalt thiocyanate (Co(SCN)2) in glycerine and water. This is followed by concentrated hydrochloric acid, and then chloroform. A positive test is indicated by a blue colour in the chloroform layer. 

Combustion-infrared, persulfate-ultraviolet oxidation, wet oxidation Adsorption-pyrolysis-titrimetric method Partition-gravimetric, partition-infrared, extraction Extraction (total phenols), distillation (volatiles), colorimetry Separation by sublation, methylene blue active substances (MBAS), anionics and cobalt thiocyanate active susbstances (CTAS), nonionic surfactants Chromatographic, distillation... 

Scott Cocaine Cobalt thiocyanate (II) solution Concentrated chloridric acid chloroform In the presence of cocaine turns from pink to blue... 

Aliphatic (primary, secondary and tertiary) amines, long chain quaternary salts and amine oxides Cobalt thiocyanate. 10 g Co(N03)26H20 and 10 g ammonium thiocyanate made up to 100 ml. Produces a blue colour. [2, 27]... 

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