Chemical gardens are characterised by the self‐assembly of mineralised abiotic architectures. Utilising the fundamental building blocks of bone mineral, namely calcium and orthophosphate ions, chemical gardens that recapitulate microstructural and compositional features of hard tissue can be grown. Interplay between orthophosphate and pyrophosphate species is highly relevant to natural mineral deposition processes, though this has yet to be explored in the context of generating biologically relevant chemical gardens. Here, tubular calcium orthophosphate‐pyrophosphate chemical gardens were grown from the interface between calcium loaded hydrogels ([Ca2+]=1 M) layered with different orthophosphate‐pyrophosphate solutions ([Pi]+[PPi]=0.7 M). We determine the effect of solution pyrophosphate content on chemical garden morphology and growth rate. Extracted structures were analysed by means of powder X‐ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM) and X‐ray fluorescence spectroscopy (XRF), revealing orthophosphate‐pyrophosphate solution dependent differences in precipitated mineral crystallinity, composition and microstructure, respectively. Lastly, the potential application of the structures is discussed in the context of tissue engineering and regenerative medicine.

The pharmaceutical industry is undergoing a paradigm shift towards continuous processing from batch, where continuous direct compression (CDC) is considered to offer the most straightforward implementation amongst powder processes due to the relatively low number of unit operations or handling steps. Due to the nature of continuous processing, the bulk properties of the formulation will require sufficient flowability and tabletability in order to be processed and transported effectively to and from each unit operation. Powder cohesion presents one of the greatest obstacles to the CDC process as it inhibits powder flow. As a result, there have been many studies investigating potential manners in which to overcome the effects of cohesion with, to date, little consideration of how these controls may affect downstream unit operations. The aim of this literature review is to explore and consolidate this literature, considering the impact of powder cohesion and cohesion control measures on the three-unit operations of the CDC process (feeding, mixing, and tabletting). This review will also cover the consequences of implementing such control measures whilst highlighting subject matter which could be of value for future research to better understand how to manage cohesive powders for CDC manufacture.