diff --git a/src/main/java/life/qbic/model/isa/NodeType.java b/src/main/java/life/qbic/model/isa/NodeType.java
new file mode 100644
index 0000000..e426dd3
--- /dev/null
+++ b/src/main/java/life/qbic/model/isa/NodeType.java
@@ -0,0 +1,5 @@
+package life.qbic.model.isa;
+
+public enum NodeType {
+  ASSAY, SAMPLE, ASSET
+}