Obtener colisiones para múltiples objetos sin las devoluciones de llamada de colisión

I'm making a platformer (sidescroller), and right now I'm making a grenade-launcher for the player.

It spawns grenades which is a prefab, this prefab has a Circle Collider 2D which is the blast radius for the explosion.

When a grenade is spawned I run this (amongst other things);

        // Add the initial force
    rBody.AddForce(new Vector2(forceX, forceY) *300f);
    Invoke("Explode", 2.5f);

I'm having trouble figuring out how I should handle the Explode function. I would like to find all the GameObjects that are colliding with the Circle Collider 2D at that point, but I can't find a way to do it.

I would like to be able to do something like this (not real code but you understand what I'm trying to do)

void Explode () {
            collidingObjects = circleCollider.getCollisions();
            foreach(collidingObject as entity) {
                if(entity = 'player')
                     player.pushLeftOrRight() 
                elseif(entity = 'enemy')
                     grenade.dealDamage(grenade.damage)
            }
    Debug.Log("Explode");
    Destroy(gameObject);
}

I'm guessing that it wouldn't work so can anyone point me in the right direction?