Can I include PTO bonds in my LNA probe?

Yes, this is possible. Please mark the respective phosphorothioate bond by an asterix (*).

A fully thioated LNA 5´ATCGAT3´ Hexamer for example shall be depicted as follows:

5´ (+A) *(+T) *(+C) *(+G) *(+A) *(+T) 3´