To save diacritics in a MySQL database you have 5 steps to follow:
1. Set(create) your database with collation utf8_general_ci;
2. Set(create) your table with utf8_general_ci collation also;
3. Make sure the text fields where you’ll insert diacritics have also the utf8_general_ci collation
4. Convert your string into ‘utf-8′ using any method you like. I recommend using PHP’s multibyte functions
e.g. $my_string = mb_convert_encoding($txt, $charset, mb_detect_encoding($my_string));
where: $my_string is the string that will be inserted
$charset is thecharset where your diacritics are included.
Check also here the Complete list of Popular character encodings
5. Before the insert query execute this query SET NAMES latin2; (if your diacritics are from one of the latin charsets)