4-Phenylspiro furan-2 , 1 -phthalan

Another commercially available fluorescing reagent, "Fluorescamine", (4-phenylspiro(furan-2-(3H),T-phthalan)3,3 -dione) reacts directly with a primary amine in aqueous acetone at a pH 8-9. 

Fluorescamine, or 4-phenylspiro[furan-2(3//),l/-phthalan]-3,3,-dione, is used to introduce a fluorescent label on electroblotted proteins via reaction with free amines. Transferred proteins are visualized on blot transfer membranes with UV light. This stain can be very sensitive and can be used in conjunction with a second detection method such as immunoblotting (also see Basic Protocol 3). However, the protein is irreversibly modified because fluorescamine reacts with available amino groups (i.e., lysines and the protein N terminus if it was not previously blocked). 

Phenylspiro[furan-2(3 H), 1 -phthalan]-3,3-dione. see Fluorescamine Pheophorbides. see also Chlorophylls Pheophytins. see also Chlorophylls Phospholipids, 523... 

Chemical name for fluorescamine is 4-phenylspiro[furan-2(3H),l-phthalan] 3,3 -dione. 

Fluorescamine (4-phenylspiro(furan-2-(3H),r-phthalan)3,3 -dione) is also a commonly used fluorescence reagent. It reacts almost instantly and selectively with primary amines, while the excess of the reagent is hydrolyzed to a non-fluorescent product. The reagent itself is non-fluorescent. The reaction is carried out in aqueous acetone at a pH of about 8-9 and the derivatives can be chromatographed directly. The excitation and emission wavelengths are 390 nm and 475 nm respectively. Two disadvantages of the reagent are its cost and the fact the products are less stable, cannot be stored and should be injected onto the column immediately after formation. Fluorescamine has been employed in the analysis of polyamines, catecholamines and amino acids. 

Phenylspiro(furan-2(3//), l -phthalan)-3,3 -dione (fluorescamine) Flur Amine (prim., sec.), hydroxyl, (thiol)... 

Two new chromophoric reagents, 2-methoxy-2,4-diphenyl-3(2/f)-furanone (MDPF) (49) and 4-phenylspiro[furan-2(3H)-r-phthalan]-3,3 -dione (fluorescamine, trade name Fluram) (50) were introduced for the correlation of... 

Fluorescamine was developed by Weigele et al. in 1972 [8], based on the fact that strongly fluorescent pyrrolinones were formed by the reaction of ninhydrin, phenylacetaldehyde, and primary amines. The reagent, 4-phenylspiro[furan-2(3H),l -phthalan]-3,3 -dione (fluorescamine), is nonfluorescent, and it reacts with primary amines, amino acids, and peptides under aqueous conditions in a few minutes at room temperature to form intensely fluorescent substances (Figure 6.1). On the other hand, nonfluorescent derivatives are formed by the reaction of fluorescamine and secondary amino compoimds. Therefore, fluorescamine can be used for the selective determination of primary amino compounds, and the fluorophore produced by the reaction is the expected pyrrolinone. Because the reaction is sufficiently rapid and the hydrolysis products are nonfluorescent, the fluorescamine reaction is applicable for the postcolumn fluorescence derivatization of primary amino compounds [9]. The amino acids are separated by a cation-exchange column similar to the ninhydrin method, and the column effluent is mixed with an alkaline-buffered solution and fluorescamine reagent. The fluorescent derivatives are detected at 480 nm with excitation at 390 nm. 

The salt washed thylakoid membranes from spinach chloroplasts were treated with a primary amine-specific fluorescent chemical modifier, Fluorescamine (4-Phenylspiro furan-2 lQ 1-phthalan 3t3 dione). The effects of this covalent chemical modification on various processes of energy transduction were studied. It is suggested that the chemical modification by fluorescamine of free amino group of coupling factor 1 results in different conformations of CFi ... 

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