The Potential of Liquid Marbles for Biomedical Applications: A Critical Review

Abstract

Liquid marbles (LM) are freestanding droplets covered by micro/nanoparticles with hydrophobic/hydrophilic properties, which can be manipulated as a soft solid. The phenomenon that generates these soft structures is regarded as a different method to generate a superhydrophobic behavior in the liquid/solid interface without modifying the surface. Several applications for the LM have been reported in very different fields, however the developments for biomedical applications are very recent. At first, the LM properties are reviewed, namely shell structure, LM shape, evaporation, floatability and robustness. The different strategies for LM manipulation are also described, which make use of magnetic, electrostatic and gravitational forces, ultraviolet and infrared radiation, and approaches that induce LM self-propulsion. Then, very distinctive applications for LM in the biomedical field are presented, namely for diagnostic assays, cell culture, drug screening and cryopreservation of mammalian cells. Finally, a critical outlook about the unexplored potential of LM for biomedical applications is presented, suggesting possible advances on this emergent scientific area.

On‐Demand Coalescence and Splitting of Liquid Marbles and Their Bioapplications

“…Recently, researchers have applied the LM to culture cells in the 3D format by manually rolling the medium on a hydrophobic powder. [35][36][37][38][39] However, the proposed method applied a tedious manual culture process and the sustained supply of nutrients and medium during medium renewal was difficult to achieve, [40] which hampered the long-time culture of the 3D cell spheroid.…”

Neuromorphic Liquid Marbles with Aqueous Carbon Nanotube Cores

“…These systems exhibit novel characteristics such as low coefficients of friction [13,14,15], which have been exploited by nature [16,17]. It has been demonstrated that liquid marbles have myriad uses ranging from micro-bioreactors [18,12,19,20] to gas biosensors [21,22] to unconventional computing media [23,24]. Our laboratory has developed LM devices that are capable of implementing computation through a variety of non-standard logics [23,24,25] where the LMs are considered as data or otherwise, to contain data (i.e.…”

Liquid Marbles as an Easy‐to‐Handle Compartment for Cell‐Free Synthesis and In Situ Immobilization of Recombinant Proteins

“…Liquid marble (LM), a self‐standing micro‐scale aqueous droplet coated with a hydrophobic material, has attracted considerable attention in biotechnological applications . Shen et al first demonstrated a blood‐typing system by generating a blood marble as a micro‐bioreactor .…”

“…[7] Liquid marble (LM), [8] a self-standing micro-scale aqueous droplet coated with a hydrophobic material, has attracted considerable attention in biotechnological applications. [9] Shen et al first demonstrated a blood-typing system by generating a blood marble as a micro-bioreactor. [10] The successful cultivation of microorganisms in LM [11] yielded cellular spheroids [12] and further the construction of a toroidal tissue structure [13] by spatially organizing LMs.…”