Read Blob object from DB and convert to System.Collection.Generic.List type of object.

I have scenario where database field stores a System.Collection.Generic.List of Double object. Now I want to read a BLOB object from database field and convert it to list of Array or any type collection in Test Complete. I have written following routine and getting null value when reading a field from record set. Can any body help how to read blob object?

function TestBlob()
{
  var serverName = "ServerName";
  var dbName = "databaseName";
  
  Conn = new ActiveXObject("ADODB.Connection");  
  Conn.ConnectionString = "Driver={SQL Server};Server=" + serverName + 
                          ";Database=" + dbName + ";Trusted_Connection=True;";
  Conn.Open();
  
  var adoCmd = new ActiveXObject("ADODB.Command");
    adoCmd.ActiveConnection = Conn;    
    adoCmd.CommandType = adCmdText;
    adoCmd.CommandText = "Select * from scan";
    var rs = adoCmd.Execute();
    
//Table Field "slices" is type of varbinary 
// and holds the Blob object of System.Collections.Generic.List of Doubles.
   
  rs.MoveFirst();
  var blob = rs.Fields("slices").Value; // Always returns null.
  
  //How can I get coverted Blob object to List of Array, I have tried to test following statement.
  //I have doubt that it will not work. 
  var objList = Aliases.appName.AppDomain("appUI.exe").dotNET.System_Collections_Generic.List_1.zctor_3(blob);

}