Fluorimetric analysis

Colorimetric and Fluorimetric Analysis. The functional groups of amino acids exhibit Htde absorption of uv light from 210 to 340 nm where uv absorption spectrometry is most conveniently conducted. Thus color or fluorescence formation reactions are employed for amino acid detection (128). 

In situ quantitation The fluorimetric analysis was made in UV light (2e,c = 313 nm, /-n > 460 nm FI 46 filter). The signal-noise ratio was better above 2 = 460 nm than when a FI 39 filter is employed. 

In situ quantitation The in situ fluorimetric analysis was made under long-wavelength UV light (2eic = 365 nm, An > 560 nm) and is illustrated in Figure 1. The detection limits for maltose, glucose and fructose were ca. 10 ng substance per chromatogram zone. 

In situ quantitation Fluorimetric analysis was made with long-wavelength UV light (2exc = 365 nm, X(, > 430 nm). The detection limit on HPTLC plates that were analyzed in a moist state was 25 ng cholesterol per chromatogram zone (Fig. 1). 

In situ quantitation The absorption-photometric determination in a reflectance mode was performed at A = 330 nm (detection limit ca. 40 ng per chromatogram zone). The fluorimetric analysis was carried out at =313 nm and An > 560 nm (detection limits ca. 10 ng per chromatogram zone) (Fig. 1). 

Fig. 2 Fluorimetric analysis of various quantities of digoxin for evaluation of the detection limit.

In situ quantitation The fluorimetric analysis of monoterpene glucosides could be performed with advantage at 2exc = 313 nm and 2 > 390 nm. The detection limits of arbutin and L-menthylglucoside were 1 — 5 ng and 15 ng substance per chromatogram respectively (Fig. 1). 

The result was that light blue fluorescent zones were visible under long-wavelength U V light (2 = 365 nm). Before fluorimetric analysis the chromatogram was dipped for 1 s into liquid paraffin — n-hexane (1 + 2) to enhance (by a factor of 2 to 8) and stabilize the intensity of the fluorescence and then dried for 1 min in a stream of cold air. The quantitation (2e,c = 365 nm An > 430 nm) was carried out after 1 h since it was only then that the fluorescence intensity had stabilized. 

Fluorimetric Analysis, Anal. Chem., Biannual Reviews, alternate years... 

In situ quantitation The fluorimetric analysis was carried out at Xexc = 313 nm and at Xfl >560 nm (cut off filter FI 56). The chromatogram zones gave a negative signal (the fluorescent background was set at 100% emission). 

In situ quantitation The fluorimetric analysis was carried out in long-wavelength UV light (Aeic = 365 nm An > 560 mn). The detection hmit for fatty acids was ca. 100 ng per chromatogram zone. 

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