SPRIselect Cleanup & Size Selection

After aspirating the desired volume of SPRIselect reagent, examine the pipette tips before dispensing to ensure the correct volume is transferred.
Pipette mix thoroughly as insufficient mixing of sample and SPRIselect reagent will lead to inconsistent results.

Use fresh preparations of 80% Ethanol.

Tutorial — SPRIselect Reagent:DNA Sample Ratios

SPRI beads selectively bind DNA according to the ratio of SPRIselect reagent (beads).

Example Ratio:	= Volume of SPRIselect reagent added to the sample	= 50 μl	= 0.5X
	Volume of DNA sample	100 μl

Schematic of Double Sided Size Selection

After the first SPRI, supernatant is transferred for a second SPRI while larger fragments are discarded (green). After the second SPRI, fragments on beads are eluted and kept while smaller fragments are discarded (blue). Final sample has a tight fragment size distribution with reduced overall amount (black).

Tutorial — Double Sided Size Selection

1. First SPRIselect: Add 50 μl SPRIselect reagent to 100 μl sample (0.5X).

Ratio:	= Volume of SPRIselect reagent added to the sample	= 50 μl	= 0.5X
	Volume of DNA sample	100 μl

2. Second SPRIselect: Add 30 μl SPRIselect reagent to supernatant from step a (0.8X).

Ratio:	= Total Volume of reagent added to the sample (step a + b)	= 50 μl + 30 μl	= 0.8X
	Original Volume of DNA sample	100 μl