ddslick plugin: get value in wordpress

I have a choice menu in WordPress plug-in with ddslick . I want to pass the id of the selected option and send the form to a database , but the value is not saved although it appears within the html . When put into manual is well maintained.

   <script type='text/javascript' src='http://g-page.co.il/wp-content/themes/g-page/js/jquery.ddslick.min.js'></script>


<div id="myDropdown">

    <select id="demo-htmlselect">




        <?php

             $thumbnails = get_posts('numberposts=5');
  foreach ($thumbnails as $thumbnail) {



    $url = wp_get_attachment_url( get_post_thumbnail_id($thumbnail->ID) );






        ?>



         <option value="<?php echo $thumbnail->ID;?>" data-imagesrc="<?php echo $url; ?>"
            data-description="<?php echo $thumbnail->post_title;?>"><?php echo $thumbnail->post_title;?></option>




    <?php } ?>

    </select>

    </div>


<?php

?>
    <div class="wrap">
        <form method="post" action="options.php">
            <?php wp_nonce_field('update-options') ?>

                <input type="text" name="main_art_id" size="45" value="<?php echo get_option('main_art_id'); ?>" />
            </p>
            <p><input type="submit" name="Submit" value="Store Options" /></p>
            <input type="hidden" name="action" value="update" />
            <input type="hidden" name="page_options" value="ain_art_id" />
        </form>
    </div>


            <script type="text/javascript">

    jQuery(document).ready(function($) {



        $('#myDropdown').ddslick({
            onSelected: function(selectedData){



                var cor_val = selectedData['selectedData']['value'];

                $("input[name=main_art_id]").val(cor_val);


            }   
        });

});



</script>


<?php



}