2 88 1 3 0 94 4 0 3 94 5 3 0 88 8__________________________________________________________________________ it was found that 0 3 n hcl eluted 90 of the copro when only copro was added to urine but that 0 3 n hcl apparently eluted 94 5 of the copro when both copro and uro were added to urine this indicates that 0 3 n hcl when used to make a copro separation in the presence of uro will elute about 4 5 of the uro the apparent approximate 4 5 increase in copro fluorescence and with 0 3 n hcl elution in the presence of uro was substantiated by recovery studies see table ii table ii______________________________________recovery studies apparent apparent copro uro copro uro______________________________________eluent hcl n 0 3 3 0 0 3 3 0recovery f u x 14 7 3 0 15 3 14 7recoverydifference 4 0 3 7 n 14______________________________________ table ii indicates that when copro and uro are present in combination there results an apparent 4 0 increase in copro fluorescense and an apparent 3 7 decrease in uro fluorescence taking this data into consideration a 4 modification was used in deriving the copro and uro level equations as shown above using the preferred process overall recovery of copro and uro using 0 3 n and 3 0 n hcl was 92 to confirm.