Nanotechnology meets flotation: Unveiling the potential of liquid biphasic systems

Nanobubble (NB) technology has emerged as a revolutionary innovation, transforming applications ranging from wastewater treatment to drug delivery. It addresses inefficiencies in conventional methods by enhancing reaction rates, delivery mechanisms, and environmental sustainability. While liquid biphasic flotation (LBF) has been widely explored for biomolecules extraction, its efficiency is often limited by the use of conventional microbubbles or macrobubbles. This review provides a comprehensive analysis of the fundamentals of LBF, the physicochemical characteristics and generation of NBs, and their synergistic potential in enhancing flotation-based applications. We further discuss the optimal NB generation techniques most suited for biphasic flotation, highlighting membrane-based methods—where gas is introduced through a sintered disc or nanoporous membrane—as the most compatible process with LBF. This ensures a continuous flotation effect while simultaneously generating stable NBs. By merging the strengths of NBs and LBF, this fusion offers promising advancements in sustainable separation technologies. However, future research will need to focus on developing an optimized NBLBF system, addressing challenges in scalable and stable NB generation for enhancing biomolecules extraction.