The solution for me was using the function readtable that it does allow as well the use of several delimeters
delimeters = {',','}',':'};
d = readtable('a.txt','Delimiter',delimeters)
d =
Var1 Var2 Var3 Var4 Var5 Var6 Var7 Var8 Var9 Var10 Var11 Var12 Var13
____________ _____ ____________ _____________________________ _____________ ______ ____ ____ ____ _____ _____ _____ _____
'{"node_id"' 'a3' 'Arrived at' '2017-07-03T14:41:58.931247Z' 'total_Light' 7273.4 'S1' 253 'S2' 534 'S3' 64 NaN
'{"node_id"' 'a3' 'Arrived at' '2017-07-03T14:42:40.290891Z' 'total_Light' 7231.6 'S1' 259 'S2' 519 'S3' 61 NaN