DBS, minimum 3 circles 

Whatmann filter paper 903

Timing of collection is critical. It is recommended that the DBS sample for Newborn screening of IEM be collected from already fed baby at the age between 48-72 hours. If a baby is to be discharged before 48 hours of age, blood can still be collected but a repeat sample at >48-72 hours may be required. This allows for early metabolic changes and the commencement of milk and protein feeds.

Making Dried blood spots (DBS) from Heel-prick or finger prick 

For normal newborn baby without any symptoms it is advisable to collect blood from heel prick. 

1. Label each card with baby’s identifications and date of collection and any other pertinent information. 

2. Wear gloves and warm the foot with warm cloth/towel.

3. Clean the side area with either alcohol swab then dry with a clean gauze or cotton wool swab. 

4. Puncture heel with sterile lancet (point <2.4 um) on medial or lateral plantar surface. 

5. Allow puncture to ooze and wipe away first drop of blood with cotton swab. 

6. Gently massage above the puncture to encourage blood flow and drop a big spot of blood onto each of the 3 circles on the filter paper 

7. Continue step e and f until all the circles are filled. One full drop of blood equivalent to 50ul is required to fill each circle. Blood must soak through the card to the other side. Do not drop more than one drop of blood on one circle. 

8. Completely dry the card at ROOM TEMPERATURE (25°C TO 30°C on a clean, flat, non-absorbent surface or a drying rack designed for the purpose, for more than 4 hours or overnight). Minimum time needed for drying is 4 hours.

9. To avoid contamination of the sample, do not touch the blood spot circle with bare hand. 

10. Place dried filter paper in an individual envelope or plastic bag for transport. It is recommended that the filter paper (dried blood spot) is store away from any source of heat, liquid and organic fumes.

Making DBS from blood collected from Venipuncture

1. Label each card with patient reference, sample collection date and any other pertinent information. 

2. Collect blood in heparinised tube (green top). If blood is drawn in a syringe, transfer it into a green tube. 

3. Set a hand-held pipettor to 50 l volume and fill the pipette tip with blood. (Note: If the tube has been sitting still for more than 2 minutes, it must be mixed by inverting it up and down few times before pipetting) 

4. Point the pipette tip at the centre of a circle on the filter paper card. Gradually discharge the blood and let it soak into the paper, filling the circle completely. 

5. Complete steps 8 to 10 as above. 

Note

• The filter paper card(s) must be completely dry before dispatch. Protect them from moisture or condensation at all times. 

• Note 2: Store at 4°C if the card is transported the next day after it is dried. Freeze at -20°C for long-term storage. 

• Note 3: The DBS must be prepared at least 4 hours ahead of transportation to allow complete drying