Optimizing Graphene Oxide Dispersion in DMSO via Ultrasonic Processing: A UV-Vis-NIR Spectroscopic Study for Biomedical Applications

This study investigates graphene oxide (GO) dispersions in dimethyl sulfoxide (DMSO) as an intermediate platform for developing nanocarriers for biomedical applications. DMSO's high polarity and hydrogen bonding ability make it an effective medium for optimizing GO's dispersion and optical properties before transferring to biocompatible systems.

GO was synthesized from glucose, and dispersions in DMSO (0.125–1.5 g/L) were prepared using mechanical stirring and ultrasonic homogenization. UV-Vis-NIR spectroscopy (200–3000 nm) was used to characterize the dispersions. Key parameters like transmittance, absorption coefficients, and bandgap width were calculated.

Controlled ultrasonic treatment produced stable dispersions with an increased molar extinction coefficient (εm ≈ 14 l·g⁻¹·cm⁻¹), indicating effective exfoliation and a rise in sp² domains. The constant optical bandgap (Eg ≈ 3.95–4.0 eV) confirmed the process was non-destructive, preserving GO's functional integrity. Spectroscopic data revealed specific GO-DMSO interactions, such as hydrogen bonding, which ensure colloidal stability.

The established dispersion patterns and spectral behaviors in DMSO can be translated to biocompatible media like aqueous buffers or amphiphilic polymers (e.g., Pluronic F127), maintaining the material's stability and optical properties. This protocol provides a universal platform for preparing GO dispersions suitable for drug delivery systems, contrast agents, and optical biosensors. The original contribution demonstrates that DMSO as an intermediate enables controlled GO dispersion and the formation of optical parameters reproducible in pharmaceutical systems.