Analysis of Nucleic Acid Related Substances

Significance of the Topic

The accurate separation and quantification of nucleic acid related compounds—including nucleosides and nucleotides—is essential in pharmaceutical development, biotechnology research and quality control. Reliable analytical methods ensure product safety, consistency and support advances in RNA-based therapeutics and metabolomics.

Objectives and Study Overview

This application note demonstrates a reversed-phase liquid chromatography method using the Shim-pack GIST C18-AQ column to separate six model compounds: hypoxanthine, inosinic acid (IMP), inosine, adenylic acid (AMP), adenosine diphosphate (ADP) and triphosphate (ATP). The goal is to achieve clear resolution within a reasonable run time on the Shimadzu Nexera system.

Methodology and Instrumentation

System and Column Setup:

• Instrument: Shimadzu Nexera UHPLC
• Column: Shim-pack GIST C18-AQ, 100 mm×3.0 mm I.D., 3 µm
• Column temperature: 30 °C
• Injection volume: 10 µL

Mobile Phase Composition:

• Phase A: Water/acetonitrile (100:1, v/v) with 0.15 M phosphoric acid and 0.225 M triethylamine
• Phase B: Water/acetonitrile (80:20, v/v) with 0.15 M phosphoric acid and 0.225 M triethylamine

Gradient Program:
0–3.5 min at 0 %B, linear to 12 %B by 11 min, ramp to 100 %B at 11.01 min, hold to 18 min, then return to 0 %B by 28 min. Detection was performed with a photodiode array at 260 nm.

Main Results and Discussion

Under the described conditions, all six analytes were baseline separated within 11 minutes of the gradient. Early eluting hypoxanthine and inosinic acid exhibited sharp peaks, while the more hydrophobic ATP eluted later under high organic conditions. Peak symmetry, reproducibility of retention times (RSD <1%) and clear resolution (Rs >1.5 for adjacent peaks) confirm method robustness.

Benefits and Practical Applications

This protocol delivers rapid, reproducible analysis suitable for routine quality control in pharmaceutical and research laboratories. The wide gradient range accommodates compounds of varying polarity, making it adaptable to additional nucleic acid analogs. The use of the GIST C18-AQ stationary phase ensures stable retention of polar analytes in aqueous conditions.

Future Trends and Potential Applications

Emerging developments include coupling this separation with mass spectrometric detection for enhanced sensitivity and structural confirmation. Miniaturized and high-throughput platforms may further increase analysis speed. Novel ion-pairing reagents and stationary phase chemistries will expand the range of detectable nucleic acid modifications.

Conclusion

The described UHPLC method on the Shim-pack GIST C18-AQ column provides a fast, reliable approach to separate and quantify key nucleic acid related substances. Its robustness and adaptability make it a valuable tool for analytical chemists working in genomics, pharmacology and biochemical research.

Reference

Shimadzu Corporation. Application News L.536, First Edition, December 2021, ERAS-1000-0134.