The ability to create uniform subnanoliter compartments using microfluidic control has enabled new approaches for analysis of single cells and molecules. However, specialized instruments or expertise has been required, slowing the adoption of these cutting-edge applications. Here, we show that three dimensional–structured microparticles with sculpted surface chemistries template uniformly sized aqueous drops when simply mixed with two immiscible fluid phases. In contrast to traditional emulsions, particle-templated drops of a controlled volume occupy a minimum in the interfacial energy of the system, such that a stable monodisperse state results with simple and reproducible formation conditions. We describe techniques to manufacture microscale drop-carrier particles and show that emulsions created with these particles prevent molecular exchange, concentrating reactions within the drops, laying a foundation for sensitive compartmentalized molecular and cell-based assays with minimal instrumentation.

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Volatile organic compounds emitted by human skin were sampled before and after acute barrier disruption of the volar forearm to investigate the significance of this approach to skin physiology research. A small wearable housing integrating a solid-phase micro-extraction fibre permitting rapid enclosed headspace sampling of human skin volatiles is presented, enabling non-invasive sample collection in 15 minutes, in a comfortable wearable format. Gas chromatography-mass spectrometry was utilised to separate and identify the volatile metabolites. A total of 37 compounds were identified, with aldehydes (hexanal, nonanal, decanal), acids (nonanoic, decanoic, dodecanoic, tetradecanoic and pentadecanoic acids) and hydrocarbons (squalane, squalene) predominant within the chemical profile. Acute barrier disruption was achieved through tape stripping (TS) of the stratum corneum to determine the impact on the volatile signature. Principle component analysis demonstrated there to be a discriminating volatile signature before and after TS. The dysregulation of significant features was examined. Several compounds derived from sebaceous components and their oxidation products were altered following barrier disruption, including squalane, squalene, octanal and nonanal. The upregulation of glycine was also observed, which may indicate a perturbation to the skin's natural moisturising factor production. TS impacted the hydro-lipid film that functions within the skin barrier, resulting in a differing volatile signature from affected skin. This provides a valuable non-invasive approach for scientific and clinical studies in dermatology, particularly around dermatological disorders associated with compromised barrier function.

A 23-month-old boy became confused and was unable to walk thirty minutes after ingesting less than 10 mL of T36-C7, a commercial product containing 100% melaleuca oil. The child was referred to a nearby hospital. His condition improved and he was asymptomatic within 5 hours of ingestion. He was discharged to home the following day. Melaleuca oil, extracted from the Melaleuca alternifolia, contains 50-60% terpenes and related alcohols. Clinical experience with products containing melaleuca oil is limited. This case report suggests that ingestion of a modest amount of a concentrated form of this oil may produce signs of toxicity.