Phishtank URL search from database

I am concerned about perform开发者_开发问答ance issues for following code

  $phishtank = @unserialize(file_get_contents('verified_online.php_serialized'));
  $found = false;
  if(is_array($phishtank)) {
     foreach($phishtank as $phishing) {
        if($phishing['url'] == 'http://88.204.202.98/login.php') {
           $found = true;
           break;
        }
     }
  }

  if($found) {
       echo 'URL found';
  }

There are 98% chances that all URLs are clean. 3 URLs take approx 6-9 sec (without profiling, random searching) in searching and due to nature of our handling we can't search all urls at once. Is there any better way to search multi URLs without going through loop every time?