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Microreactor technology is an interdisciplinary field that combines science and engineering. This new concept in production, analysis and research is finding increasing application in many different fields. Benefits of this new technology pose a vital influence on chemical industry, biotechnology, the pharmaceutical industry and medicine, life science, clinical and environmental diagnostic. In the last few years, together with microplant development, a great part of research investigation is focused on integrated micro-systems, the so called micro-total-analysis-systems (μ-TAS) or lab-on-chip (LOC). They are devices that perform sampling, sample preparation, detection and date processing in integrated model. Cell sorting, cell lysis, single cell analysis and non-destructive single cell experiments on just one microreactor, makes the LOC platform possible. Clinical diagnostic devices are also leaning towards completely integrated, multiple sophisticated biochemical analyses (PCR amplification, cell lysis, separation and detection) all on a single platform and in real time. Special attention is also paid to the usage of microdevices in tissue. Tissue engineering is one of the most promising fields that can lead to in vitro tissue and organ reconstruction ready for implantation and microdevices can be used to promote the migration, proliferation and the differentiation of cells in controlled situations.

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A mathematical model for hexanol oxidation catalyzed by NAD+‐dependent alcohol dehydrogenase from baker's yeast in a microreactor was developed and compared with the model when the reaction takes place in a macroscopic reactor. The enzyme kinetics was modeled as a pseudo‐homogeneous process with the double substrate Michaelis–Menten rate expression. In comparison with the kinetic parameters estimated in the cuvette, a 30‐fold higher maximum reaction rate and a relatively small change in the saturation constants are observed for the kinetic parameters estimated in the continuously operated tubular microreactor (Vm1=197.275 U/mg, Kmhexanol=9.420 mmol/L, and Km1NAD+=0.187 mmol/L). Kinetic measurements performed in the microreactor, estimated from the initial reaction rate experiments at the residence time of 36 s, showed no product inhibition, which could be explained by hydrodynamic effects and the continuous removal of inhibiting products. The Fourier amplitude sensitivity test method was applied for global kinetic parameter analysis, which shows a significant increase in the sensitivity of Km1NAD+ in the microreactor. Independent experiments performed in the microreactor were used to validate and to verify the developed mathematical model.

Biodiesel, which was earlier used only as an alternative fuel, is now an indispensable component of commercial diesel. Conventional production processes are unable to cope with the increasing demand for biodiesel, and therefore more and more work is being done to intensify the existing processes. The intensification of the biodiesel production process, taking into account the environmental and economic factors, is based on increasing productivity. One way to achieve that is by reducing the volume of production units. The application of the enzymatic reaction path, while reducing the volume of process equipment to the micro-level, has significantly magnified the productivity of the biodiesel production process, which is primarily due to better mass transfer in microsystems. Additional breakthrough is the use of deep eutectic solvents (DES) instead of buffers for enzyme stabilization. In this study, a lipase from Thermomyces lanuginosus (TlL) (both commercial and produced by solid-state fermentation) was used as a catalyst for biodiesel production. Edible and waste sunflower oil, as well as methanol, were used as substrates. The reaction mediums were buffer and DES. The transesterification reaction was carried out in a batch reactor and the emphasis was made on different microreactor configurations. The highest yield of 32% for residence time of only τ = 30 min was obtained in the microreactor system with an emulsion of waste oil and a commercial enzyme suspended in a buffer. This indicates that enzymatic transesterification could be a valuable reaction path for dealing with waste oils. Furthermore, biodiesel synthesis in DES showed somewhat lower yields, but by increasing the water content in the system, the reaction could prove much better results. In the end, the effects of reaction conditions on the volumetric productivity of the process were analyzed.

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A combination of flow chemistry and batch-based synthetic procedures has been successfully applied to the assembly of novel 4,5-unsaturated l-ascorbic acid series 6a–6n with diverse C-6-substituted 1,2,3-triazole moiety.