$some_content = 'so long Asian character (maybe it contain single quotation)';
$sql = "insert into test_table(field) values ($dbh->quote($some_content))";
$dbh->do($sql); # you know, this works.

##</code><code>##

$some_content = $dbh->quote('so long Asia character (maybe it contain single quotation)');
$sth = $dbh->prepare("insert into test_table(field) values (?)");
$sth->execute($some_content);
$sth->finish();