Reagent blood-gelatin

If the substances separated on a TLC plate are not directly visible and do not react to UV light, they can be caused to absorb light or to fluoresce by reaction with suitable reagents. In the case of biological reactions, the result can be obtained, for example, as the hemolytic index (HI) on coating the plate with blood-gelatin or as the measured values found from an enzymatic inhibition test. 

Practical Tips for coating TLC plates with blood-gelatin reagent ... 

After the chromatography, the plate, from which the solvent has been removed, is surroimded on all four sides by a 3-cm wide adhesive textile band so that a border ca. 1 cm high is formed which will prevent the blood-gelatin reagent applied later from miming off (Fig. 88a,b). Using a spirit level, the plate is placed on a horizontal substrate (Fig. 88a). 

Figure 89 shows a plate, coated and reacted with a blood-gelatin reagent to reveal the chromatograms of saponin, early golden-rod herb, soapwort, horsetail herb and primula root. The colored strip also included shows the accuracy of the color reproduction of the plate (see also Section 8.3.2 Photography using 35-mm Cameras ). 

Figure 89. Identification of hemolyzing plant constituents after derivatization with the blood-gelatin reagent (shot taken in white light)...

Acetic anhydride is an important industrial reagent. Over one-half its annual production of approximafely 750,000 fons is used for the manufacture of cellulose acetate. Cellulose acetate is a wddely used textile fiber and is the chief component of cigarette filters. Acetic anhydride is the acetylation reagent used for the production of aspirin (acetylsalicylic acid). Succinic anhydride finds use in the succinylation of gelatin used as a blood plasma substitute, as a food preservative in chicken against Salmonella, and as a dog food preservative. 

Proteins can be bonded onto substrates by chemical treatments or ionization methods such as y-ray irradiation. However, with such treatments, special attention should be paid to residues from the chemical reagents and property changes in the substrate. On the other hand, texturization by the salt casting method needs only sodium chloride, which, even if not completely removed, is not harmful biologically, and does not change the chemical or mechanical properties of the substrate. We believe that glutaraldehyde-treated gelatin on textured substrates is one of the best materials for use in blood pumps and is useful for other biomaterial applications as well. 

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