pdf export with unicode using mpdf

[eluser]Bigil Michael[/eluser]
code used in my model to insert contents to db

Code:

$data = array(
     'description' => ascii_to_entities($this->input->post('description')) ,
            
   );

now updated the db collation to utf8_general_ci

now db content is like this

Code:

<p align="JUSTIFY"><span  karthika; font-size: medium;">ഇത്  ഒരു ടെസ്റ്റ്‌ വർക്ക്‌ ആണ് </span></p>

reading contents from db like this

Code:

$row =   $this->Authors_model->get_selected($selected_authors);
  $data['description'] = entities_to_ascii($row->description);

when i echo contents like print_r($data['description']) it prints ഇത് ഒരു ടെസ്റ്റ്‌ വർക്ക്‌ ആണ്
when i export it shows square boxes

if i save statically like $data['decription'] = 'ഇത് ഒരു ടെസ്റ്റ് വർക്ക് ആണ് ';
exports perfectly.

i searched a lot but didn't get any solution.
can you tell me is it a database issue ????