How to save the binary data (a File) from an xml node as a file.

I have one database with a BLOB column. I have saved a file in that column. Using the Recordset.Save adXMLpersist, i have saved the entire data into an XML file. Now the xml file has all the data.
That BLOB data (a big file) is saved as hexadecimal numbers in a node. Now I want to read that data and save it into a file. i.e I want the original file which i have uploaded to the database. How to save the data. Using Open file for Binary access write method, it is saving the same binary data to the file. It is not converting the data.