Escapar Comillas Simples de MYSQL

[pmeninsaxmus16]

Esta es mi query

Código:

$sql="SELECT concat(concat(concat(concat(trim(a.firstname),' '),trim(a.middlename)),' '),trim(a.lastname)) FROM ABCIsystemBundle:AbcMembers a WHERE concat(concat(concat(concat(trim(a.firstname),' '),trim(a.middlename)),' '),trim(a.lastname)) ='".addslashes($cad2)."'";
                $repositorio = $this->getEntityManager()->createQuery($sql); 
                try {  
                        $results = $repositorio->getSingleResult();
                        $filtro = implode(' ', $results);  //comvierte a string el array
                        $convert=(string)$filtro;        
                        return $convert;
                    } 
                catch (\Doctrine\Orm\NoResultException $e) { $repositorio = null; }
            }

y me tira siempre este error

Código:

[Syntax Error] line 0, col 269: Error: Expected end of string, got 's' 

QueryException: SELECT concat(concat(concat(concat(trim(a.firstname),' '),trim(a.middlename)),' '),trim(a.lastname)) FROM ABCIsystemBundle:AbcMembers a WHERE concat(concat(concat(concat(trim(a.firstname),' '),trim(a.middlename)),' '),trim(a.lastname)) ='Samuél Juan Chepon Rodriguez\'s Melendez'

ya sea con el addslashes ó mysql_real_escape_string

y en el debug arroja esto