diff --git a/python/plugins/processing/algs/qgis/IdwInterpolation.py b/python/plugins/processing/algs/qgis/IdwInterpolation.py
index 2707482f2de..a72212a36d1 100644
--- a/python/plugins/processing/algs/qgis/IdwInterpolation.py
+++ b/python/plugins/processing/algs/qgis/IdwInterpolation.py
@@ -76,10 +76,10 @@ class ParameterInterpolationData(QgsProcessingParameterDefinition):
     def dataToString(data):
         s = ''
         for c in data:
-            s += '{}, {}, {:d}, {:d};'.format(c[0],
-                                              c[1],
-                                              c[2],
-                                              c[3])
+            s += '{}::~:: {}::~:: {:d}::~:: {:d};'.format(c[0],
+                                                          c[1],
+                                                          c[2],
+                                                          c[3])
         return s[:-1]
 
 
@@ -144,7 +144,7 @@ class IdwInterpolation(QgisAlgorithm):
         layerData = []
         layers = []
         for row in interpolationData.split(';'):
-            v = row.split(',')
+            v = row.split('::~::')
             data = QgsInterpolator.LayerData()
 
             # need to keep a reference until interpolation is complete
diff --git a/python/plugins/processing/algs/qgis/TinInterpolation.py b/python/plugins/processing/algs/qgis/TinInterpolation.py
index 8cfd325b6d5..0839017a4bb 100644
--- a/python/plugins/processing/algs/qgis/TinInterpolation.py
+++ b/python/plugins/processing/algs/qgis/TinInterpolation.py
@@ -80,10 +80,10 @@ class ParameterInterpolationData(QgsProcessingParameterDefinition):
     def dataToString(data):
         s = ''
         for c in data:
-            s += '{}, {}, {:d}, {:d};'.format(c[0],
-                                              c[1],
-                                              c[2],
-                                              c[3])
+            s += '{}::~:: {}::~:: {:d}::~:: {:d};'.format(c[0],
+                                                          c[1],
+                                                          c[2],
+                                                          c[3])
         return s[:-1]
 
 
@@ -160,7 +160,7 @@ class TinInterpolation(QgisAlgorithm):
         layers = []
         crs = QgsCoordinateReferenceSystem()
         for row in interpolationData.split(';'):
-            v = row.split(',')
+            v = row.split('::~::')
             data = QgsInterpolator.LayerData()
 
             # need to keep a reference until interpolation is complete
diff --git a/python/plugins/processing/algs/qgis/ui/InterpolationDataWidget.py b/python/plugins/processing/algs/qgis/ui/InterpolationDataWidget.py
index b4a31817565..1df90b93ba2 100644
--- a/python/plugins/processing/algs/qgis/ui/InterpolationDataWidget.py
+++ b/python/plugins/processing/algs/qgis/ui/InterpolationDataWidget.py
@@ -152,10 +152,10 @@ class InterpolationDataWidget(BASE, WIDGET):
                 else:
                     inputType = QgsInterpolator.SourceBreakLines
 
-            layers += '{},{:d},{:d},{:d};'.format(layer.source(),
-                                                  interpolationSource,
-                                                  fieldIndex,
-                                                  inputType)
+            layers += '{}::~::{:d}::~::{:d}::~::{:d};'.format(layer.source(),
+                                                              interpolationSource,
+                                                              fieldIndex,
+                                                              inputType)
         return layers[:-1]