A new method to estimate rhodium in different samples at trace levels had been developed. Rhodium was
complexed with 5-(40-nitro-2 0,6 0-dichlorophenylazo)-6-hydroxypyrimidine-2,4-di one (NDPHPD) as a
complexing agent in an aqueous medium and concentr ated by using Triton X-114 as a surfactant. The
investigated rhodium complex was preconcentrated with cloud point extraction process using the non-
ionic surfactant Triton X-114 to extract rhodium comp lex from aqueous solutions at pH 4.75. After the
phase separation at 50 C, the surfactant-rich phase w as heated again at 100 C to remove water after
decantation and the remaining phase was dissolved using 0.5 mL of aceton itrile. Under optimum condi-
tions, the calibration curve was linear for the concentration range of 0.5–75 ng mL 1
and the detection
limit was 0.15 ng mL 1
of the original solution. The enhancement factor of 500 was achieved for
250 mL samples containing the analyte and relative standard deviations were 61.50%. The method
was found to be highly selective, fairly sensitive, simple, rapid and economical and safely applied for rho-
dium determination in different complex materials such as synthetic mixture of alloys and environmen-
tal water samples.