Quantitative determination of amino acids on filter paper staining in two stages

1953 ◽  
Vol 11 ◽  
pp. 209-214 ◽  
Author(s):  
B. Pernis ◽  
Ch. Wunderly
1961 ◽  
Vol 39 (2) ◽  
pp. 417-425 ◽  
Author(s):  
A. T. Matheson ◽  
E. Tigane ◽  
C. S. Hanes

An improved ninhydrin–hydrindantin reagent has been developed for the quantitative determination of amino acids and peptides separated on filter paper chromatograms. This represents a modification of a reagent described earlier, which was based in turn upon the well-known solution of Moore and Stein. The present reagent has been in use for several years and has shown the advantages of high stability, extremely low and steady reagent blank values, and approximately stoichiometric yields of Ruhemann's purple for most amino acids. In addition to its use for determinations on excised areas from filter paper chromatograms, conditions are defined for the use of the reagent for determinations of amino acids in solutions.


2016 ◽  
Vol 9 ◽  
pp. 66-73 ◽  
Author(s):  
Krishna Prasad Rai ◽  
Hasta Bahadur Rai ◽  
Santosh Dahal ◽  
Saroj Chaudhary ◽  
Suraj Shrestha

Energy drinks are non-alcoholic beverage intended to enhance the psycho-physiological responses in human, which is especially popular among young generation in Nepal. It is normally high caffeinated drink added with other ingredients such as carbohydrates, amino acids, B-group of vitamins etc. In this study, 10 brands of energy drink available in Nepalese markets were taken then analyzed for quantitative determination of Caffeine and Taurine by HPLC-UV method. From the result obtained, pH and TSS values of energy drinks were found in the range of 2.96-3.81 and 6.64-18.21 respectively. Likewise, the Caffeine and Taurine content in same samples were found in the range of not detected (ND) to 35.78 mg/100 ml and ND to 387.5 mg/100 ml respectively. Only the 6 samples out of 10 were confi rmed caffeine content as per claimed in label, while only 3 samples were confi rmed for Taurine content as per label claimed. Based on this pilot study, the majority of samples did not meet the label claims in term of Caffeine and Taurine, which apparently indicated the misbranding of such drinks. Since, there is no any regulation for such energy drinks in Nepal, it seems to be a great challenge for regulation of their safety and misbranding.


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