diff --git a/NF.jsonld b/NF.jsonld
index 473ebcaa..dd7b67fe 100644
--- a/NF.jsonld
+++ b/NF.jsonld
@@ -4669,6 +4669,8 @@
       "@id" : "bts:Skindex-16"
     }, {
       "@id" : "bts:multi-electrodearray"
+    }, {
+      "@id" : "bts:nanoparticletrackinganalysis"
     }, {
       "@id" : "bts:n-backtask"
     }, {
@@ -5004,6 +5006,8 @@
       "@id" : "bts:Skindex-16"
     }, {
       "@id" : "bts:multi-electrodearray"
+    }, {
+      "@id" : "bts:nanoparticletrackinganalysis"
     }, {
       "@id" : "bts:n-backtask"
     }, {
@@ -8941,6 +8945,17 @@
     },
     "sms:displayName" : "University of Texas M. D. Anderson Cancer Center",
     "sms:required" : "sms:false"
+  }, {
+    "@id" : "bts:nanoparticletrackinganalysis",
+    "@type" : "rdfs:Class",
+    "rdfs:comment" : "TBD",
+    "rdfs:label" : "nanoparticletrackinganalysis",
+    "rdfs:subClassOf" : [ ],
+    "schema:isPartOf" : {
+      "@id" : "http://schema.biothings.io/"
+    },
+    "sms:displayName" : "nanoparticle tracking analysis",
+    "sms:required" : "sms:false"
   }, {
     "@id" : "bts:UniversityofKentucky",
     "@type" : "rdfs:Class",
diff --git a/modules/Assay/Assay.yaml b/modules/Assay/Assay.yaml
index 86bc6793..ebb3f207 100644
--- a/modules/Assay/Assay.yaml
+++ b/modules/Assay/Assay.yaml
@@ -369,6 +369,9 @@ enums:
           Cells, such as cardiomyocytes or neurons, which are electrically active, can be cultured over the electrodes creating a cohesive network. 
           The functional behavior or electrical activity of this network can be recorded.
         source: https://www.axionbiosystems.com/multielectrode-array
+      nanoparticle tracking analysis:
+        description: Particle sizing technique based on Brownian motion and scattered light.
+        meaning: http://purl.enanomapper.org/onto/ENM_0000065
       n-back task:
         description: A task in which items (e.g., letters) are presented one at a time and participants must identify each item that repeats relative to the item that occurred "n" items before its onset.
         meaning: https://www.cognitiveatlas.org/task/id/tsk_4a57abb949bcd/