response from my PDO Class... WTF?

"Array
(
    [:uid] => 1
    [:content] => kjgrliueajrghkerg
    [:ip_address] => 127.0.0.1
    [:privacy] => 0
)
Array
(
    [ok] =>
    [msg] => SQLSTATE[HY093]: Invalid parameter number: :content INSERT INTO s0cF_posts (user_id, post_content, ip_address, privacy) VALUES ( :uid, ':content', ':ip_address', :privacy )
)

This is the post function that is returning this response:

    function post_status( $uid, $privacy, $content ) {
        $content = pg_escape_string($content);
        $ip = $_SERVER['REMOTE_ADDR'];
        $prepared = $this->prepare( "INSERT INTO ".TP."_posts (user_id, post_content, ip_address, privacy) ".
                                    "VALUES ( :uid, ':content', ':ip_address', :privacy )" );
        $post_array = array(
            ':uid'              => $uid,
            ':content'      => $content,
            ':ip_address'       => $ip,
            ':privacy'          => $privacy );
        print_r($post_array);
        try {
            $this->setAttribute( PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION );
            $this->beginTransaction();
            $prepared->execute( $post_array );
            echo $prepared->queryString;
            $post_id = $this->lastInsertId('post_id_seq');
            $post_meta_array = array(
            ':direct_link' => "posts/$uid/$post_id");
            $prepared = $this->prepare( "INSERT INTO ".TP."_post_meta () ".
                                        "VALUES ( 'direct_link', ':direct_link' )" );
            $prepared->execute( $post_meta_array );
        } catch ( PDOException $e ) {
            $db_err = $e->getMessage();
            $this->rollBack();
            $response = array(
                'ok'    =>  false,
                'msg'   =>  $db_err." ".$prepared->queryString );
            return $response;
        }
        $this->commit();
        $response = array(
            'ok'    =>  true,
            'msg'   =>  "Success! $prepared->queryString" );
        return $response;
    }

        "