Reinsch test

The Reinsch Test.12 When a strip of polished copper foil is placed in a solution of arsenious acid a grey film is formed on the copper owing to deposition of arsenic and formation of copper arsenide, Cu5As2. The deposition occurs in the cold with concentrated solutions, but only on warming with dilute solutions. It is possible to detect by this means... 

Detection Dry Tests, Wet Tests, Bettendorffs Test, Thiele s or Bougault s Test, The Reinsch Test. 

This sample should be examined visually for colour and the presence of tablet residues or excipients (often maize starch). The odour should be noted as tiiis may indicate the presence of alcohols, aldehydes, ketones, phenols, cyanide, ethchlorvynol, nicotine, etc. The following tests, details of which are given on p. 5, should be performed Trinder s test for salicylates, cresol-ammonia test for paracetamol, FPN reagent for phenothiazines, Fujiwara test for trichloro-compounds, and the diphenyl- nine test for oxidising agents. In addition, tiie Reinsch Test for heavy metals (p. 57) should be carried out, and a diluted, filtered extract examined by direct ultraviolet spectrophotometry for drugs with highyl values. 

Group 4 poisons should be checked as a matter of routine if vomiting and diarrhoea are noted as symptoms, no matter what other poisons may be suggested by medical opinion or circumstantial evidence. Although the Reinsch Test (p. 57) will detect only seven of the twenty potentially toxic metals, it can be applied to almost any material (body fluids, slmried tissue, food Mid (hinks) without Miy elaborate prepM ation, and it is sensitive enou to detect toxic concentrations of tiie most common poisonous metals in a few minutes. However, it misses too many metals for it to be considered as a complete group exclusion test. 

Warm the main bulk of the sample on a water-bath, note any odour, and test the sample with appropriate test papers (pH, lead acetate, silver nitrate, starch). Apply the Reinsch Test for metals (p. 57). 

After the application of the Reinsch Test, filter the sample and retain the solids and the filter paper. Use small aliquots of the filtrate to test for borate (p. 64), and phosphate. 

Reinsch test. A test for detecting small amounts of arsenic, silver, bismuth, and mercury. 

Reinsch test,—The suspected liquid is acidalated with one-sixth its bulk of HGl strips of electrotype copper are immersed in the liquid, which is boiled. In the presence of an arsenious compound a gray or bluish deposit is formed upon the Cu. A similar deposit is produced by other eubatances (Bi,... 

Poisoning by arsenic compounds is occasionally encountered in the laboratory. The toxic action of arsenic is due to its inhibition of sulphydryl enzymes. It can be detected in body fluids by the Reinsch test which is based on the reduction of arsenic to its elemental form by metallic copper in the presence of acid. The arsenic is deposited on the coppier as a dark film. 

Keacts with Reinsch s test (. v.), but gives no sublimate in the glass tube. 

Hantak MM, Grant T, Reinsch S, Mcginnity D, Loring M, ToyookaN, et al. Dietary Alkaloid Sequestration in a poison frog and experimental test of alkaloid uptake in Melanophryniscus stelzneri (Bufonidae). J Chem Ecol 2013 39(ll-12) 1400-6. 

Reinsch s Test If As is boiled with HCl and a thin strip of bright Cu foil, the As is deposited on the copper as a gray film, not As, but apparently a copper arsenide. (Note that As is reduced far less readily.) With much As, the coating separates as scales. The HCl must be at least 3-M overall. This determines very well the presence or absence of As in HCl (diluted to 3 M). A trace of arsenic (4 ppm), if present, will soon coat the foil. 

More specifically, an aqueous antimony salt, when heated with iron wire in the presence of HCl, or with metallic Mg, Zn or Sn, gives a black precipitate of Sb (distinction from Sn). Copper in concentrated HCl (Reinsch s test) becomes coated with a violet deposit if Sb is present. If a drop of solution containing antimony is placed on a silver coin, or other silver, and the coin touched through the drop with a piece of tin or zinc, an identifying black spot of Sb will form. Sulfides interfere. 

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