Effect of pH on the isolation of urinary exosome.
OBJECTIVE
Urinary exosome is an ideal noninvasive, low-cost source of kidney diseases biomarkers. However, many factors effect the isolation of urine-derived exosome. The effect of pH on the yield of exosome isolation under different pH was explored.


METHODS
The pH was adjusted for 4, 5, 6, 7 and 8 with hydrochloric acid and sodium hydroxide solution. All samples were incubated for 30 min before differential ultracentrifugation. Exosome-associated protein markers TSG101, ALIX and total concentration of RNA were evaluated by Western-blotting and micro-amount ultraviolet spectrophotometer, respectively.


RESULTS
A major loss of urinary exosome was received at pH 8 compared with alkali medium or control group. There was no difference whether or not added EDTA-Na2.


CONCLUSIONS
Acidic environment was likely to conducive to the isolation of exosome and maintain its stability and integrity that suggest pH medium needs to be carefully considered and also provide a methodology for future separation exosome.
Medical Technology Institute of Xuzhou Medical University, Xuzhou, 221004, China.
Yao
Y
Zhao
Department of Clinical Laboratory, People's Hospital of Guanyun, Lianyungang, 222001, China.
Kaiyong
K
Chen
Center of Research Laboratory, Lianyungang Hospital Affiliated to Xuzhou Medical College, 182 Tongguan Road, Lianyungang, 222001, China.
Haining
H
Li
Center of Research Laboratory, Lianyungang Hospital Affiliated to Xuzhou Medical College, 182 Tongguan Road, Lianyungang, 222001, China. 18961326009@163.com.
Huiyi
H
Wu
D000328:Adult; D015415:Biomarkers / Q000652:urine; D002135:Calcium-Binding Proteins / Q000652:urine*; D018797:Cell Cycle Proteins / Q000652:urine*; D004268:DNA-Binding Proteins / Q000652:urine*; D056827:Endosomal Sorting Complexes Required for Transport / Q000652:urine*; D055354:Exosomes; D005260:Female; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007674:Kidney Diseases / Q000652:urine*; D008297:Male; D012313:RNA / Q000302:isolation & purification* / Q000652:urine; D014157:Transcription Factors / Q000652:urine*; D014461:Ultracentrifugation; D055815:Young Adult; D000099177:Tsg101 Protein
D015415:Biomarkers; D002135:Calcium-Binding Proteins; D018797:Cell Cycle Proteins; D004268:DNA-Binding Proteins; D056827:Endosomal Sorting Complexes Required for Transport; D012313:RNA; D014157:Transcription Factors; D000099177:Tsg101 Protein; C117020:PDCD6IP protein, human
EDTA-Na2; Proteins; RNA; Urinary exosome; pH
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