Apparatus for simultaneously analyzing vanillylmandelic acid, homovanillic acid and creatinine

Claim 1

An apparatus for analyzing a test solution comprising vanillylmandelic acid, homovanillic acid and creatinine and other acidic components by fast liquid chromatography, which comprises a cation exchange resin column means for separating creatinine from vanillylmandelic acid and homovanillic acid in a test solution, an anion exchange column means for partially fractionating vanillylmandelic acid and homovanillic acid from other acidic components, a separation column means for separating vanillylmandelic acid and homovanillic acid, a first detector means for detecting creatinine, a second detector means for detecting vanillylmandelic acid and homovanillic acid, a first flow path switching valve means for changing the path of eluent from a first path directing said eluent into said cation exchange resin column means to a second path preventing said eluent from entering said cation exchange resin column means, and a second flow path switching valve means for changing the path of eluent from a third path directing said eluent into said anion exchange resin column means to a fourth path preventing said eluent from entering said anion exchange resin column means, wherein said first switching valve means, said cation exchange resin column means and said first detector means are connected sequentially in series to define a flow system means for separating and detecting creatinine, and said first switching valve means, said cation exchange resin column means, said second switching valve means, said anion exchange resin column means, said separation column means and said second detector means are connected sequentially in series to define a flow system means for separating and detecting vanillylmandelic acid and homovanillic acid.

Claim 2

An apparatus for analyzing a test solution comprising vanillylmandelic acid, homovanillic acid and creatinine and other acidic components by fast liquid chromatography, which comprises a cation exchange resin column means for separating creatinine from vanillylmandelic acid and homovanillic acid in a test solution, an anion exchange column means for partially fractionating vanillylmandelic acid and homovanillic acid from other acidic components, a separation column means for separating vanillylmandelic acid and homovanillic acid, a first detector means for detecting creatinine, a second detector means for detecting vanillylmandelic acid and homovanillic acid, a first flow path switching valve means for changing the path of eluent from a first path directing said eluent into said cation exchange resin column means to a second path preventing said eluent from entering said cation exchange resin column means, and a second flow path switching valve means for changing the path of eluent from a third path directing said eluent into said anion exchange resin column means to a fourth path preventing said eluent from entering said anion exchange resin column means, wherein said first switching valve means, said cation exchange resin column means and said first detector means are connected sequentially in series to define a flow system means for separating and detecting creatinine, and said first switching valve means, said cation exchange resin column means, said second switching valve means, said anion exchange resin column means, said separation column means and said second detector means are connected sequentially in series to define a flow system means for separating and detecting vanillylmandelic acid and homovanillic acid.