A0.25g of quinine in antimalarial tablet was dissolved in sufficient 0.1 M HO to make 1% w/v solution. A 10-ml aliquot was then diluted to 250 ml with the acid. The fluorescence intersity for the diluted sample at 347.5 nm provided a reading of 140. A standard 120 ppm quinine solution registered 280 when measured under conditions identical to those for the diluted sample. The theoretical concentration of the final solution is ppm.