New Ht independent dried blood spot cards discussion Ynze Mengerink Barcelona, November 21 st 2013
What is the Hematocrit effect ? Page 1
DBS Card 2 drops 2 drops 2 drops 1 drops 2 drops 3 drops Ht 20 Ht 45 Ht 80 Ht 45 Ht 45 Ht 45 Punch center Punch center Each Punch contains not the same volume of blood Each Punch contains same volume of blood Page 2
Ht effect on commercial available DBS Cards Influence of Hematocrit on Spot Size 1,25 1,20 1,15 =1) Normalized spot size (Ht45% 1,10 1,05 903 DMPK B 1,00 DMPK A 0,95 Bond Elute DMS 0,90 DMPK C 0,85 0,80 0,75 20 30 40 50 60 70 80 % Hematocrit Page 3
What causes the Hematocrit effect ? Page 4
Page 5
Page 6
Page 7
Page 8
Page 9
Page 10
Page 11
Page 12
Page 13
Page 14
Page 15
Page 16
Page 17
Page 18
Bloodspot spreading 8,0 Whatman S pot size Whatman Core 7,0 diameter of spot (arbitrary units) 6,0 5,0 4,0 3,0 2,0 1,0 0,0 0 1 2 3 4 5 6 7 8 time of spot formation (arbitrary units) Page 19
How does our new material work • Woven polyester material, fiber and mesh size in µm range – Large enough to transfer blood cells and small enough to retain dried blood • Multi layers – Typically eight layers, spot size relates to number of layers • Coated with a very hydrophilic coating and UV cured Page 20
Page 21
Page 22
Page 23
Page 24
Page 25
After a few seconds Page 26
After a few minutes Page 27
Bloodspot spreading 8,0 DS M card S pot size 7,0 diameter of spot (arbitrary units) 6,0 DS M card Core 5,0 4,0 3,0 2,0 1,0 0,0 0 1 2 3 4 5 6 7 8 time of spot formation (arbitrary units) Page 28
Bloodspot spreading 8,0 DS M card S pot size 7,0 DS M card Core diameter of spot (arbitrary units) 6,0 Whatman S pot size 5,0 Whatman Core 4,0 3,0 2,0 1,0 0,0 0 1 2 3 4 5 6 7 8 time of spot formation (arbitrary units) Page 29
Influence of Hematocrit Page 30
So, this looks like a holy grail to reduce study animals ?? Page 31
4 layers no orientation of layers Page 32
Page 33
Page 34
Page 35
Page 36
After a few seconds Page 37
After a few minutes Page 38
After an hour Page 39
S ingle layer – aged blood Page 40
0 graden Page 41
3 Degrees angle Page 42
10 graden Page 43
15 graden Page 44
45 graden Page 45
Orientation of layers Page 46
How the card is build Page
Not orientated material Page 48
Orientated material Page 49
Results: Spot Homogeneity LCMSMS Card 1 Card 2 PUNCH SPOT 1 SPOT 2 SPOT 3 SPOT 4 SPOT 5 SPOT 6 AVG RSD MIDDLE 10. 1 9. 7 9. 8 9. 8 10. 3 10. 4 10. 0 3 LEFT 10. 4 9. 9 10. 1 10. 3 10. 2 9. 4 10. 1 3 RIGHT 10. 8 10. 7 10. 4 11. 7 11. 5 10. 7 11. 0 5 DOWN 11. 1 11. 0 11. 7 10. 1 9. 9 11. 1 10. 8 7 AVG 10. 6 10. 3 10. 5 10. 5 10. 4 10. 4 Average 10. 47 RSD 4 6 8 8 7 7 RSD (n=24) 6 Page 50
Results: Recovery from full spot Page 51
Results: Dry time Page 52
Results: Tunable spot size Page 53
Results: External tests Test at GS K confirmed excellent spot size independency towards Hematocrit, but some preliminary results of tests between whole and punched spot show biased results and are under investigation. Page 54
Conclusions • Very interesting new material, shows spot sizes, which are independent of hematocrit value of the blood sample • Fixed spot size at exact volume, as a consequence, blood volume on card can be determined on spot size. • Two patents in place (card and coating) • A startup company is being established, to commercialize this product Page 55
Acknowledgements • DS M: Jun Qiu (our 007), Ellen Gorissen, Nik de Bont and John Mommers • Chemelot: Odile S teij ger, Henri Theunissen and Bert Kip • Ministry of Economic Affairs If they could only analyze my blood on a DBS card, without to worry about the Ht effect Page 56
Recommend
More recommend
