Table 2.

An Outline of Four Different Library Preparation Workflows Evaluated in This Study

Variable	Library preparation workflow
	1	2	3	4
Input cfDNA quantity, ng	30	30	30	30
End-repair reaction volume, μL	60	60	60	60
Post–end-repair purification	−	+	−	−
End-repair carryover volume, μL	60	60	30 (3A) and 30 (3B)	30 (4A) and 30 (4B)
10 mmol/L Tris-Cl, μL			30 (3A) and 30 (3B)
Ligation mix volume, μL	30	30	30 (3A) and 30 (3B)	30 (4A) and 30 (4B)
Postligation purification	+	+	+	+
First PCR	+	+	+	+
Post−PCR purification	+	+	+	+
Hybridization capture: DNA, ng	1500	1500	1500	1500
Hybridization capture: baits, ng	7.5	7.5	7.5	7.5
Second PCR	+	+	+	+
Post−PCR purification	+	+	+	+

Note that in workflows 3 and 4, after the end-repair reaction, volume was split into two tubes and processed independently up to the first PCR amplification postpurification step.

cfDNA, cell-free DNA.