If the request is for both 24-hour urinary creatinine and urinary phosphate (and/or urinary calcium), only one 24-hour acidified bottle is required.
Record start and end date/time of collection on bottle/request form.
Non-acidified urine collections should be mixed thoroughly by inversion 5 times immediately prior to acidification (prior to analysis). Acidify to pH < 2.
Weight, aliquot and record volume on bottle/request form.