Binding variables codeigniter

I need the user id's param to not have single quotes. I've tried trim and a few other things but it does not work? I think maybe I need to define it as integer but the fact is, it's IDs are with commas like "9166,2234,2256,9987" so if I cast it to int it just takes the first number...

        $user_ids = "9166,2234,2256,9987";
        $start_date = "2017-05-25 00:00:00";
        $end_date = "2021-05-25 00:00:00":

        $params[] = $user_ids;
        $params[] = $start_date;
        $params[] = $end_date;

                $sql = "SELECT DISTINCT*
                    date(user_certificates.created_date) AS date,
                    user_certificates.user_id,
                    user_certificates.event_id AS course_id
                    FROM user_certificates
                    join event_skills on event_skills.event_id = user_certificates.event_id
                    join events on events.id = user_certificates.event_id
                    WHERE 1=1
                    $certificate_type_condition
                    and event_skills.skill_id = 0 and events.is_teqtivity = 0
                    AND user_certificates.user_id IN (
                         ?
                    )
                    AND user_certificates.created_date >= ? AND user_certificates.created_date <= ?
                ";

        $query = $this->db->query($sql, $params);

        return array($query->result(), $this->db->last_query());

Note, the query needs to look like this if hardcoded(but it has single quotes around the IDs list so will not work):

SELECT DISTINCT date(user_certificates.created_date) AS date, user_certificates.user_id, user_certificates.event_id AS course_id 
FROM user_certificates 
join event_skills on event_skills.event_id = user_certificates.event_id 
join events on events.id = user_certificates.event_id 
WHERE 1=1 
and event_skills.skill_id = 0 
and events.is_teqtivity = 0 
AND user_certificates.user_id IN (9166,2234,2256,9987) 
AND user_certificates.created_date >= '2017-05-25 00:00:00' 
AND user_certificates.created_date <= '2021-06-25 23:59:59 23:59:59'

source https://stackoverflow.com/questions/68135856/binding-variables-codeigniter