Storing scanned document using TWAIN in microsoft sql server management studio using Windows form c#

Question

I am new in using TWAIN in scanning documents. I have already managed to scan documents but stuck at storing them. Here is a sample of my code. (Without the CONVERT command before the "ddnTwain.CurrentImageIndexInBuffer" I get an error saying I should use the CONVERT function and I did xD)

    con.Open();
    cmd = new SqlCommand(@"INSERT INTO FileArchive"
                           (FFTitle, FDesc, FIssuer, FType, FFile,
                            FDatePassed, FDatestored, FAuthentication,
                            FStoredby)
                           VALUES
                           ('"+txtscanTitle.Text+"','"+txtscanDesc.Text+@"',
                           '"+txtscanIssuer.Text+"', '"+ScanFT+"',(CONVERT(varbinary(max),'"+ddnTwain.CurrentImageIndexInBuffer+@"')),
                           '"+ScanDP+@"',
                           '"+DateTime.Now.Date.ToShortDateString()+@"',
                           'Authenticated', '"+SBName.Text+"')", con);
    cmd.ExecuteNonQuery();
    con.Close();