dmpk c cards facilitated the recovery of 45 55 of the cytokine while only 2 3 was recovered from the dmpk a and b cards see table 1 and fig1 the 903 and dmpk c cards are the basic base papers and have not been dipped or coated with any chemical whilst the dmpk a and b cards are coated with a proprietary mixture of chemicals that facilitate the denaturation and inactivation of proteins micro organisms and cells respectively these cards have been designed to facilitate the transportation and prolonged storage of nucleic acids therefore the low il 2 recovery levels observed when using the dmpk a and b cards may actually be a reflection of the presence of these denaturing reagents and the elisa based antibody detection system used the elisa detection system requires the eluted il 2 to exhibit an intact native structure no il 2 recovery was observed when the cytokine was dissolved in pbs irrespective of the paper type used data not shown the il 2 recovery levels observed in the absence of added il 2 were essentially equivalent to background levels indicating that the edta anti coagulated blood contain negligible amounts of endogenous il 2 data not shown several chemicals were used to saturation dip the 903 neonatal std and dmpk c cards some of which appeared to facilitate the recovery of elevated il 2 levels compared to non dipped papers p value lt 0 05 for both the 903 neonatal std and dmpk c cards tables 2 and 3 fig2 and 3 chemicals such as poly vinyl pyrolodine poly 2 ethyl 2 oxazoline albumin and casein facilitated a significant increase in il 2 recovery levels mean gt 55 compared to u02dc 45.