The fluorescence spectral behavior of interaction of phenylfluorone(PF)-Mo(VI) and protein was investigated in Triton X-100 microemulsion medium at pH 2.0. A novel method for the determination of protein using phenylfluorone (PF)-Mo(VI) as a fluorescence spectrum probe was developed. Excitation and emission wavelengths are 465 and 525 nm, respectively. The effective factors and the optimum conditions have been studied, and the reducing value of fluorescence intensity is in proportion to the concentration of proteins in the range 0-6.00 mu g(.)L(-1) for bovine serum albumin, 0-4.00 mu g(.)L(-1) for human serum albumin, 0-5. 00 mu g(.)L(-1) for ovalbumin, and 0-4.00 mu g(.)L(-1) for lysozyme. The Triton X-100 microemulsion was efficiently used to enhance the sensibility and stability of the system, and the limits of detection are 5.4, 5.2, 1.5 and 8.2 mu g(.)L(-1), respectively. Most of foreign substances do not interfere with the determination, and this method has good selectivity and high sensitivity. It has been applied to the determination of proteins in the urine samples with satisfactory results.
