एक पीले रंग की डाई जो अत्यधिक पतला होने पर भी दिखाई दे रही है; एक अवशोषण संकेतक के रूप में उपयोग किया जाता है जब सिल्वर नाइट्रेट समाधान सोडियम क्लोराइड में सिल्वर क्लोराइड में जोड़ा जाता है (गुलाबी हो जाता है जब कोई क्लोराइड आयनों को समाधान में नहीं छोड़ा जाता है और नकारात्मक फ्लोरोसिसिन आयनों को अवशोषित किया जाता है

fluorescein's Usage Examples:

Control of transglutaminase activity in human keratinocytes by using the newly developed fluorescein cadaverine incorporation technique.

aspheric designs, principles of fitting, fluorescein patterns, photorefractive surgery, diabetes and red eye.

A subset of patients also had fluorescein angiography performed every 6 months.

A special form of angiography used by eye doctors is called fluorescein angiography.

One defect a fluorescein angiogram test may reveal are abnormal blood vessels which leak blood into the surrounding tissues.

Fluorescein >>

This tautomerism may be of a twofold nature :-(I) it may involve the mere oscillation of linkages, as in acridine; or (2) it may involve the oscillation of atoms, as in fluorescein.

a-pyrone condenses with the benzene ring to form coumarin and isocoumarin; benzo-'y-pyrone constitutes the nucleus of several vegetable colouring matters (chrysin, fisetin, quercetin, 'c., which are derivatives of flavone or phenyl benzo-y-pyrone); dibenzo--ypyrone is known as xanthone; related to this substance are fluorane (and fluorescein), fluorone, fluorime, pyronine, 'c. The pyridine ring condenses with the benzene ring to form quinoline and isoquinoline; acridine and phenanthridine are dibenzo-pyridines; naphthalene gives rise to a-and /3-naphthoquinolines and the anthrapyridines; anthracene gives anthraquinoline; while two pyridine nuclei connected by an intermediate benzene nucleus give the phenanthrolines.

Unlike resorcin it does not give a fluorescein with phthalic anhydride.

This oscillation may be represented in the case of acridine and fluorescein as This theory brings the property of fluorescence into relation with that of colour; the forms which cause fluorescence being the coloured modifications: ortho-quinonoid in the case of acridine, paraquinonoid in the case of fluorescein.

fluorescein's Meaning':

a yellow dye that is visible even when highly diluted; used as an absorption indicator when silver nitrate solution is added to sodium chloride in order to precipitate silver chloride (turns pink when no chloride ions are left in solution and negative fluorescein ions are then absorbed