Backup DB with stored procedure and a parameter for the destination

I would like to create a little backup SP that I can pass a parameter that contains the location so a user could backup to any location they wanted.  I started with this but it doesn't seem to work:

CREATE PROCEDURE [dbo].[ISRBackup]
                @Location  nvarchar(255)
AS
BACKUP DATABASE [ISR] TO  DISK = @Location WITH NOFORMAT, INIT,  NAME = N'ISR-Full Database Backup', SKIP, NOREWIND, NOUNLOAD,  STATS = 10

any suggestions?