Effect of hydrated deep eutectic solvents on the thermal stability of DNA

DNA’s structure stability in hydrated deep eutectic solvents (DESs) is getting growing attention for emerging bio-applications. The employment of DESs as novel co-solvents in water media could favor eco-friendly and biodegradable materials for DNA storage and handling. Understanding the molecular interactions between nucleic acids and aqueous DES is crucial for developing newgeneration solvents for biomolecules. In this work, we exploit the molecular sensitivity and selectivity of synchrotron radiation UV resonance raman (SR-UVRR) spectroscopy to explore the interplay between a choline chloride:urea (ChCl:U) DES and double-stranded DNA. Our study analyzes the impact of ChCl:U on the DNA’s thermal unfolding pathway by focusing on the guanine nucleobases whose Raman signal could be strongly enhanced through careful tuning of the excitation wavelength.