diff --git a/workflow/main.nf b/workflow/main.nf
index 636cb533635e2ccbffe8bf88a590776bb409393b..e4853866a9890a900bd761be3090232a114587a1 100644
--- a/workflow/main.nf
+++ b/workflow/main.nf
@@ -164,8 +164,10 @@ process filterReads {
 }
 
 // Define channel collecting new design file
-dedupDesign = dedupReads.
-              collectFile(name:'design_dedup.tsv', seed:"sample_id\tbam_reads\tbam_index\tbiosample\tfactor\ttreatment\treplicate\tcontrolId\n", storeDir:"$baseDir/output/design")
+dedupDesign = dedupReads
+              .map{ sampleId, bam, bai, biosample, factor, treatment, replicate, controlId ->
+              "$sample_id\t$bam\t$bai\t$biosample\t$factor\t$treatment\t$replicate\t$controlId\n"}
+              .collectFile(name:'design_dedup.tsv', seed:"sample_id\tbam_reads\tbam_index\tbiosample\tfactor\ttreatment\treplicate\tcontrolId\n", storeDir:"$baseDir/output/design")
 
 // Quality Metrics using deeptools
 process experimentQC {