scholarly journals Determination of Sodium Xylene Sulphonate and Lignin Substances in the Hydrotropic Process with the Ultraviolet Absorption Method

1960 ◽  
Vol 14 (3) ◽  
pp. 170-175
Author(s):  
Hiroshi Asaoka ◽  
Sadao Takahashi ◽  
Kanemichi Suzuki ◽  
Shin-ichi Ito
Keyword(s):  
Ultraviolet Absorption ◽  
Absorption Method

Sorting Procedure for the Determination of Vanillin in Vanilla Extracts by Ultraviolet Absorption

1966 ◽  
Vol 49 (3) ◽  
pp. 571-571
Author(s):  
Frank J Feeny
Keyword(s):  
Collaborative Study ◽  
Ultraviolet Absorption ◽  
Absorption Method

Abstract Further collaborative study was conducted on the ultraviolet absorption method for vanillin, 19.008. Results indicated that the method should be adopted as official, final action as a sorting procedure for vanillin.

Analysis on Heat Coagulated Blood and Serum

1964 ◽  
Vol 10 (10) ◽  
pp. 937-941 ◽  
Author(s):  
Jesse H Marymont ◽  
Morris London
Keyword(s):  
Ultraviolet Light ◽  
Reduction Method ◽  
Serum Urate ◽  
Ultraviolet Absorption ◽  
Boiling Water ◽  
Absorption Method ◽  
Shell Vial

Abstract A direct ultraviolet absorption method that does not require uricase for the determination of serum urate is presented. Serum (0.3 ml.) is placed in the bottom of a 25 X 95-mm. shell vial and coagulated by immersion of the vial in boiling water for 2 min. The clot is overlaid with 3.0 ml. of water and the serum urate extracted for 60 min. at 37°. The absorbance of the extract is measured at 295 mµ, and the serum urate determined by comparison with the known absorption of pure urate at the same wavelength. The agreement between the direct ultraviolet method and a standard phosphotungstate reduction method is excellent in cases in which no medication is being administered. Some drugs absorb ultraviolet light, and in certain instances may be responsible for a discrepancy up to 1.5 mg./100 ml. between the two procedures. The method is extremely simple and requires no reagents.

Quantitative Determination of Vanillin and Ethyl Vanillin in Flavors by Paper Chromatography

1964 ◽  
Vol 47 (6) ◽  
pp. 1161-1165
Author(s):  
J Fitelson
Keyword(s):  
Quantitative Determination ◽  
Paper Chromatography ◽  
Alkaline Solution ◽  
Chromatographic Separation ◽  
Chromatographic Method ◽  
Ultraviolet Absorption ◽  
Photometric Method ◽  
Absorption Method ◽  
Ethyl Vanillin

Abstract Previous methods for estimating vanillin and ethyl vanillin in mixtures were long and complicated. However, this paper presents a simple chromatographic separation and quantitative determination of these aromatics, using Mitchell equipment for paper chromatography and 8 × 8” papers. Development for 2 hours separates the compounds adequately; they are then extracted and measured by absorbances at 348 mμ in alkaline solution. Recoveries of added vanillin and ethyl vanillin to vanilla extract are excellent. Aside from normal manipulative errors, the only significant inaccuracy is caused by the small amount of natural p-hy-droxybenzaldehyde in vanilla (usually equivalent to about 5% of the vanillin content). The method does not separate p-hydroxybenzaldehyde and vanillin. Total errors in the method do not exceed 0.01%. Comparison of the method with the two AOAC methods for vanillin shows that the paper chromatographic method gives results close to those by the ultraviolet absorption method, in most cases, and significantly lower results than the photometric method, which is known to give erroneously high results.

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