JSON转义字符

我有一个字符串，由于'&q'(我猜)在原始字符串中被转义而过早终止。如果我想在PHP中保留原始字符串，我该如何处理?

'http://answers.onstartups.com/search?tab=active&q=fbi'

var_dump的结果

'["http://answers.onstartups.com/search?tab=active'

JS

var linksStr = $("#links").val();
var matches = JSON.stringify(linksStr.match(/'bhttps?:'/'/[^'s]+/gi));
    $.ajax({
      type: 'GET',
      dataType: 'json',
      cache: false,
      data: 'matches=' + matches,
      url: 'publishlinks/check_links',
      success:                    
        function(response) {
        alert(response);
        }
    })    

check_links

$urls = $this->input->get('matches');        
var_dump($urls);