Preparation of urine samples for proteomic analysis

Area of Science:

• Urine proteomics
• Biomarker discovery
• Protein sample preparation

Background:

• Reproducible protein sample preparation from human urine is vital for proteomic analysis.
• Applications include novel protein discovery and biomarker identification for diseases and drug treatments.

Purpose of the Study:

• To present a methodology for preparing human urine protein samples.
• To minimize protein loss during sample preparation.
• To enrich proteins based on molecular weight for downstream analysis.

Main Methods:

• Urine proteins separated from cellular debris via centrifugation.
• Concentration using 5-kDa-cutoff membrane devices.
• Size exclusion chromatography to fractionate proteins by molecular weight (>30 kDa and <30 kDa).
• Optional affinity removal of abundant plasma proteins.
• Buffer exchange for downstream applications like 2D electrophoresis and LC-MS/MS.

Main Results:

• A reproducible protocol for human urine protein isolation.
• Minimized protein loss through optimized precipitation and separation techniques.
• Two distinct protein fractions enriched by molecular weight.

Conclusions:

• The presented methodology enables efficient and reproducible preparation of human urine protein samples.
• This approach supports comprehensive proteomic analyses, including biomarker discovery.
• The protocol is adaptable for various downstream proteomic techniques.