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Standard Protocol for Urine Collection and Storage
(Applicable for the analysis of soluble urine proteins;
not for exosome analysis)
 
Normal Urine (Adults)

• Negative for protein by dipstick tests: <15 mg/dl
• Protein/creatinine ratio: <0.2 g/g
• 24 hour urinary protein: < 150 mg/day

		Practical Recommendation
1	Timing	Collect mid-stream of random-catch urine or the 2nd morning urine
2	Preservatives	No need if urine is kept at RT and frozen within 4 hours but add NaN2 to 10 mM (or Boric acid to 0.2 M) if frozen more than 4 hours after collection
3	Proteinase inhibitors	No need for normal urine (Further evaluations will be done for proteinuric urine)
4	Pretreatment & Storage	Centrifuge at 1000g for 10 min to remove cells and debris, and store aliquots of 10 (or 50 or 1.5) ml at -20 or -80°C
5	Freezing & Thawing	Avoid as much as possible and thaw in 37°C water bath

 
Notes:

1	The 2nd morniing urine and collection in sterile urine cup are preferable.
2	Keeping at 4°C is preferable but not essential.
3	Protease inhibitors may be necessary for proteinuric urine samples, but not for normal urine samples unless exosome analysis is planned.
4	Centrifugation is desirable to minimize proteins releasing from insoluble contents (cells and casts).
5	Adjustment of urine pH to 8.0 with 1 M Tris buffer (pH 8.0) may help solubilization of aggregates after thawing. Times of freezing and thawing need to be recorded. Samples with identical freeze-thaw history should be used for comparison proteomics

 
Notes:
Minimum infomation of samples General

1. Sample number
2. Storage temparature (-20 or -80C)
3. Institution
4. Date-time of collection
5. Hours until freezing
6. Volume and number of aliquots

Case

1. Anonymized case name or number
2. Clinical diagnosis or helthy
3. Age
4. Gender
5. Height
6. Weight

Laboratory data

1. Urinary protein amount
2. Urine creatinine
3. Hematuria
4. Serum creatinine
5. Serum protein or albumin
6. (Urine pH)
7. (Serum cholesterol)