Table 1.
Quantum yields of some possible standards
| Compound | Q | Standard, Qst |
|---|---|---|
| 2-Aminopyridine, 0.1 N H2SO4 | *0.74 | 9,10-diphenylanthraoene, 1.0 |
| Do | .73 | tryptophan, 0.12 |
| Do | .74 | quinine, 1 N H2SO4, 0.55 |
| Trytophan, water | *.12 | 9,10-diphenylanthracene, 1.0 |
| Do | .12 | quinine, 1 N H2SO4, 0.55 |
| l-dimethylaminonaphthalene-5-sulfonate, 0.1 M NaHCO3 | .34 | Do. |
| 4Methylumbelliferone, 0.01 M NaOH | .64 | Do. |
| 4-Methylumbelliferone, 0.01 M HCl | .65 | Do. |
| 5-Hydroxyindole (serotonin), pH 7.4 | .23 | Do. |
| Tyrosine, water | .13 | Do. |
| Phenylalanine, water | .022 | Do. |
| Phenol, water | .13 | Do. |
| l-dimethylaminonaphthalene-5-sulfonamide, pH 7.4 | .051 | Do. |
All values were obtained by the author with the Aminco-Bowman spectrofluorometer and a Gary Model 11S spectrophotometer, except for those marked (*). The latter were determined with a Turner Model 210 spectrofluorometer. The author is indebted to Dr. H. Edelhoch for the use of this instrument.