A Novel HPLC-Based Method to Investigate on RNA after Fixation

Area of Science:

• Biochemistry
• Molecular Biology
• Analytical Chemistry

Background:

• RNA extracted from fixed and paraffin-embedded tissues is crucial for biomedical research and molecular pathology.
• Standardization of RNA isolation methods is essential for reliable diagnostic outcomes.
• Understanding the impact of tissue fixation on RNA quality is critical for accurate downstream analysis.

Purpose of the Study:

• To establish and validate a high-performance liquid chromatography (HPLC) method for assessing RNA integrity after fixation.
• To investigate the effects of various fixatives on RNA chemical modifications.
• To evaluate the influence of pre-analytical conditions on RNA preservation in tissue samples.

Main Methods:

• Development of an HPLC-based analytical method.
• Enzymatic digestion of RNA extracts using Nuclease S1.
• Quantification of unmodified nucleotide monophosphates (NMPs) and detection of RNA modifications via HPLC.
• Analysis of mouse liver tissues and clinical samples processed with different fixation protocols.

Main Results:

• The developed HPLC method accurately quantifies NMPs and identifies RNA modifications.
• Alcohol-based fixatives, when used according to ISO standards, do not induce significant chemical modifications in RNA.
• Pre-analytical conditions, including fixation methods, significantly impact RNA preservation.
• Analysis of aged clinical samples (0-30 years) further supported findings on RNA stability.

Conclusions:

• Alcohol-based fixatives are suitable for preserving RNA integrity under standard conditions.
• The established HPLC method provides a reliable tool for evaluating RNA quality in fixed tissues.
• Optimizing pre-analytical conditions is paramount for ensuring high-quality RNA suitable for research and diagnostics.