diff --git a/docker/Dockerfile b/docker/Dockerfile
index e1d3308..66b3f44 100644
--- a/docker/Dockerfile
+++ b/docker/Dockerfile
@@ -15,7 +15,7 @@ RUN conda install -y -c conda-forge \
     nglview=4.0.1 \
     ipywidgets=8.1.9
 RUN pip install --no-cache-dir \
-    mdtraj==1.11.1
+    mdtraj==1.11.1 \
     mdplus==0.1.2
 
 COPY docker/fix-nglview.sh /tmp/fix-nglview.sh