Abstract

Hypoxia (low oxygen) is a major challenge in various chronic diseases, and recent advances in micro/nanobubble (MNB) technology offer a promising solution for oxygen delivery. However, the impact of MNBs on oxygen availability within 3D tissue engineering scaffolds, particularly hydrogels, remains unexplored. This study addresses this gap by developing a homemade and novel hydrogel formulation named here as “ViaCox-Gel”, which incorporates MNBs and micro/nanodroplets (MNDs) for enhanced oxygenation. This study employs a vacuum degasification technique for the efficient generation of bulk MNBs and MNDs suspensions within a polymeric solution containing perfluorocarbon (PFC) liquids. Subsequently, following UV crosslinking, both MNBs and MNDs are successfully encapsulated within the hydrogel network. We employed Dynamic Light Scattering (DLS), Nanoparticle Tracking Analysis (NTA), zeta potential analysis, FT-IR spectroscopy, and a fiber-optic oxygen sensor to characterize the MNB and MND nano-entities within ViaCox-Gel. The produced MNBs and MNDs exhibited a high concentration (5.1x10^9 particles/mL) with a size distribution of 300 nm and a negative zeta potential (-15 mV). ViaCox-Gel demonstrated a significant improvement in oxygen delivery compared to control hydrogels without MNBs or MNDs. It sustained an oxygen release profile of 2 mg/L for 60 minutes, while control hydrogels released no measurable oxygen. Scanning electron microscopy (SEM) revealed that MNB and MND incorporation via ViaCox-Gel resulted in hydrogels with approximately 40% porosity. Furthermore, diffusion rates were significantly higher in hydrogels with larger pores compared to those with smaller pores. Surface analysis suggested that MNBs and MNDs remained present on the hydrogel surface after polymerization, potentially influencing surface nanoroughness compared to controls. This study demonstrates the potential of ViaCox-Gel, a hydrogel formulation integrating MNBs and MNDs, as a versatile platform for tissue engineering applications. ViaCox-Gel offers improved oxygen release, tunable porosity, and diffusivity, and potentially influences surface nanotopography. These advancements highlight its multifaceted role in pushing the boundaries of biomaterial design for tissue engineering.