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fashion? Following the findings of nature itself, for which the liquid phase hasbeen the essential ground for the emergence of chemical complexity and life,we focus on those processes involving manipulation of liquid phase on themicroscale and, in particular, those offering homogeneous and reproducible 

yield .

The last two decades have witnessed an explosive expansion in the under-standing of capillary processes; this knowledge has served human creativityand the development of a number of technologies now considered forming aparticular field of fluid mechanics: microfluidics. In this field, the intelligentcombination of imposed geometries (devices) on small scales, surface tensionand bulk forces tuned at precise intensities provides the tools to manipu-late matter in an unprecedent way. Here, droplets, bubbles, microcapsules,microfibers, etc. become basic building blocks of new functional materials,intelligent ingredients and APIs. While mass productivity pertains func-tional product manufacturing enough for current human demands, control

of the microscopic scale directly influences product delivery to an individualorganism. This review aims to provide a gross mapping of current scientificand technological knowledge in the field, in the quest for those current toolscombining highest productivity with maximal control on the microscale andreproducibility.

APIs can be present in many forms: solid dispersions (powders made upof solid particles), suspensions (powders in liquids) of any kind, emulsions(droplets of any size in immiscible liquids), solutions (API’s molecules dis-persed in a solvent), etc. Nearly always, a fragmentation process is involved inthese forms. The most controllable way to fragment a bulk material involvesits reduction to liquid phase (melting or dissolution), fragmenting the liquid

phase into droplets by the use of specific tools, and applying a further stepto solidify it (freezing or desolvation), if necessary. In general, a high degreeof care put into the liquid fragmentation step demands a careful subsequentsolidifying step as well, to prevent undesired coalescence . Interestingly, someresearchers have successfully proposed the use of electric charges to preventsuch coalescence [38]. However, fragmentation involves manipulation toolsadapted to the inherent nature of this process: first, it always stores energy 

in the form of surface tension, and second, this storage should be as ordered 

as compatible with the functionality and control sought for, thus minimiz-ing entropy. These demands go against Thermodynamics in many aspects.Therefore, the inventive steps involved in the design of liquid fragmentationtools are much taller than those demanded in subsequent solidifying steps.

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