Targeted physical therapy for gouty arthritis: a first-principles frequency-screening study

Introduction Gouty arthritis is caused by the deposition of monosodium urate monohydrate (MSUM) crystals in joints. Current drug therapies are often limited by side effects, and invasive procedures carry associated risks. This study aims to provide a theoretical basis for local physical treatment of gout by identifying specific mid-infrared frequencies for irradiating MSUM crystals via photon-phonon resonant absorption. Methods The vibrational spectra of crystalline MSUM were simulated using first-principles density functional theory. The infrared and Raman peaks were mapped to their corresponding vibrational modes, and relative infrared activities were analyzed. The infrared spectrum of an anhydrous monosodium urate model (anhydrous MSU) was also calculated. Results Analysis of the vibrational spectra revealed infrared characteristic peaks at 1637 and 1696 cm - ¹ for MSUM and at 1627 and 1705 cm - ¹ for anhydrous MSU. This finding provides the theoretical foundation for scanning 1627–1705 cm - ¹ (48.78–51.11 THz) to resonantly excite the crystals. Discussion The irradiation of MSUM crystals with a mid-infrared laser near 50 THz is proposed for initial frequency-scanning experiments. A optical fiber placed near deeper deposits could shorten the distance traveled through tissue. However, experimental validation is required to determine suitable irradiation conditions and assess safety and efficacy.