Ninhydrin spray

RS- P-Aminoisobutyric acid (a-methyl-P-alanine) [10569-72-9] M 103.1, m 176-178 , 178-180 , 181-182 , R -(-)- isomer [144-90-1] m 183 , [a] -21 (c 0.43, HjO), pKes,(,) 3.7, pKEst(2) 10.2. Colorless prisms from hot H O, were powdered and dried in vacuo. The purity is checked by paper chromatography (Whatman 1) using ninhydrin spray to visualise the amino acid Rp values in 95% MeOH and n-PrOH/5N HCOOH (8 2) are 0.36 and 0.50 respectively. [Kupiecki and Coon Biochem Prep 7 20 7960 Pollack J Am Chem Soc 65 1335 7943.] The R-enantiomer, isolated from iris bulbs or human urine was crystd from H2O and sublimed in vacuo [Asen et al. J Biol Chem 234 343 7959]. The RS-hydrochloride was recrystd from EtOH/Et20 m 128-129 , 130° [Bbhme et al. Chem Ber92 1258, 1260, 1261 7959]. 

The eluent front was marked on the glass plates prior to drying over a hot plate. Amino acids were visualized as purple spots by application of the ninhydrin spray reagent to the plate and drying with hot air. Amino acids with zero mobility (Rf = 0 in BUOH/HAC/H2O) are assumed to be cross-links (Keller et al., 1984). 

A glacial acetic acid/pyridine/ddH20 50 5 945 (v/v/v), pH 3.4 B ninhydrin spray 0.3 g ninhydrin dissolved in 100 ml n-butanol... 

Aprotinin Silica gel Acetate buffer Ninhydrin spray Rf and colour of the analyte spot is compared with standard... 

Identification of amino acids by chromatography. Use a 4 1 2 mixture of butanol, ethanoic acid and water as a solvent. Dry the chromatogram and develop with a ninhydrin spray. 

What happens if you don t use gloves and your finger comes in contact with the ninhydrin spray ... 

Ninhydrin spray reagent (0.2% ninhydrin in ethanol or acetone). Do not use any reagent older than 6 months. 

The solvent systems described immediately above are useful in evaluating the general character of the PE sample. Only one word of caution, as regards use of the basic solvent systems, is that the plate must be thoroughly air-dried before using the ninhydrin spray. 

The reaction is allowed to continue until TLC (Whatman KIF, ethyl acetate-pyndine-acetic acid-water, 10 5 1 3) shows that the unprotected amino acid (Rf 0.4) is no longer present, as evidenced by negative ninhydrin spray. 

Ninhydrin spray solution (Dissolve 1 g of ninhydrin in 500 ml of w-butanol. Add 0.5 ml of 2,4-collidine just before use.)... 

Thin-layer Chromatography. System TA—Rf 26 system TB—Rf 11 system TC—Rf 00. (Dragendorff spray, positive acidified iodoplatinate solution, positive Marquis reagent, brown ninhydrin spray, positive acidified potassium permanganate solution, positive.)... 

Thin-layer Chromatography. System TA—Rf 57. (Ninhydrin spray, positive.)... 

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