diff --git a/output/sample-Na-26-015-nexus.nx b/output/sample-Na-26-015-nexus.nx
deleted file mode 100644
index 533a243..0000000
Binary files a/output/sample-Na-26-015-nexus.nx and /dev/null differ
diff --git a/src/classes.py b/src/classes.py
index 98a4883..813a7fa 100644
--- a/src/classes.py
+++ b/src/classes.py
@@ -224,6 +224,7 @@ class Entrypoint:
             self.extra = sample_data["metadata_decoded"]["extra_fields"]
             self.linked_items = sample_data["items_links"]  # dict
             self.batch_elabid = self.extra["Substrate batch"]["value"]  # elabid
+            self.proposal = self.extra["Proposal"].get("value") or None  # proposal
             self.linked_experiments = sample_data["related_experiments_links"]  # dict
             self.linked_experiments_elabid = [
                 i["entityid"] for i in self.linked_experiments
diff --git a/src/main.py b/src/main.py
index 8e1c868..0cbc2a3 100755
--- a/src/main.py
+++ b/src/main.py
@@ -877,12 +877,22 @@ if __name__ == "__main__":
     data = handler.get_entry_from_elabid(elabid)
     sample = Entrypoint(data)
     sample_name = sample.name.strip().replace(" ", "_")
+    if sample.proposal:
+        sample_proposal = sample.proposal.strip().replace(" ", "_")
+    else:
+        sample_proposal = None
     substrate_object = chain_entrypoint_to_batch(sample)  # Substrate-class object
     layers = chain_entrypoint_to_layers(sample)  # list of Layer-class objects
     n_layers = len(layers)  # total number of layers on the sample
     result = make_nexus_schema_dictionary(substrate_object, layers)
     # print(make_nexus_schema_dictionary(substrate_object, layers)) # debug
-    with open(f"output/sample-{sample_name}.json", "w") as f:
+    fn_base = (
+        "nffa-di_"
+        + (f"{sample_proposal}_" if sample_proposal else "")
+        + "Napoli_"
+        + sample_name
+    )
+    with open(f"output/{fn_base}.json", "w") as f:
         json.dump(result, f, indent=3)
     # TO-DO: remove the hard-coded path of the RWA file
     # ideally the script should download a TXT/CSV file from each layer
@@ -895,4 +905,4 @@ if __name__ == "__main__":
     # In this test I will only consider one image.
     # TO-DO: make it format-agnostic. If not possible, make it PNG-only.
     # mx = mx.astype(np.float32) / 255.0  # consider deleting???
-    build_nexus_file(result, output_path=f"output/sample-{sample_name}-nexus.nx")
+    build_nexus_file(result, output_path=f"output/{fn_base}.h5")