How do I make a database row be a global?

PHP Code:

<?php
class MY_Admin extends CI_Controller {

public $me;

public function __construct()
    {
            parent::__construct();
            $this ->load->database();  
            $this->me = "testing 123";

    }

} 


Then in your controller:

PHP Code:

public function somefunc() {

   echo $this->me;

} 


I did that but I still get the same error.

Undefined property: Admin::$me

I would like a database row to be accessible from all controllers.