This critical review summarizes developments in microfluidic platforms that enable the miniaturization, integration, automation and parallelization of (bio-)chemical assays (see S. Haeberle and R. Zengerle, Lab Chip, 2007, 7, 1094–1110, for an earlier review). In contrast to isolated application-specific solutions, a microfluidic platform provides a set of fluidic unit operations, which are designed for easy combination within a well-defined fabrication technology. This allows the easy, fast, and cost-efficient implementation of different application-specific (bio-)chemical processes. In our review we focus on recent developments from the last decade (2000s). We start with a brief introduction into technical advances, major market segments and promising applications. We continue with a detailed characterization of different microfluidic platforms, comprising a short definition, the functional principle, microfluidic unit operations, application examples as well as strengths and limitations of every platform. The microfluidic platforms in focus are lateral flow tests, linear actuated devices, pressure driven laminar flow, microfluidic large scale integration, segmented flow microfluidics, centrifugal microfluidics, electrokinetics, electrowetting, surface acoustic waves, and dedicated systems for massively parallel analysis. This review concludes with the attempt to provide a selection scheme for microfluidic platforms which is based on their characteristics according to key requirements of different applications and market segments. Applied selection criteria comprise portability, costs of instrument and disposability, sample throughput, number of parameters per sample, reagent consumption, precision, diversity of microfluidic unit operations and the flexibility in programming different liquid handling protocols (295 references).

/pdf/microfluidic-lab-on-a-chip-platforms-requirements-3q5qdadspt.pdf

Microfluidic lab-on-a-chip platforms: requirements, characteristics and applications

5-Hydroxymethylfurfural (HMF) as a building block platform: Biological properties, synthesis and synthetic applications

Recent years have seen considerable progress in the development of microfabricated systems for use in the chemical and biological sciences. Much development has been driven by a need to perform rapid measurements on small sample volumes. However, at a more primary level, interest in miniaturized analytical systems has been stimulated by the fact that physical processes can be more easily controlled and harnessed when instrumental dimensions are reduced to the micrometre scale. Such systems define new operational paradigms and provide predictions about how molecular synthesis might be revolutionized in the fields of high-throughput synthesis and chemical production.

https://www.gene-quantification.de/nature-review-3-lab-on-chip-2006.pdf

Control and detection of chemical reactions in microfluidic systems

Flow chemistry involves the use of channels or tubing to conduct a reaction in a continuous stream rather than in a flask Flow equipment provides chemists with unique control over reaction parameters enhancing reactivity or in some cases enabling new reactions This relatively young technology has received a remarkable amount of attention in the past decade with many reports on what can be done in flow Until recently, however, the question, “Should we do this in flow?” has merely been an afterthought This review introduces readers to the basic principles and fundamentals of flow chemistry and critically discusses recent flow chemistry accounts

The Hitchhiker's Guide to Flow Chemistry

In the past few years, continuous-flow reactors with channel dimensions in the micro- or millimeter region have found widespread application in organic synthesis. The characteristic properties of these reactors are their exceptionally fast heat and mass transfer. In microstructured devices of this type, virtually instantaneous mixing can be achieved for all but the fastest reactions. Similarly, the accumulation of heat, formation of hot spots, and dangers of thermal runaways can be prevented. As a result of the small reactor volumes, the overall safety of the process is significantly improved, even when harsh reaction conditions are used. Thus, microreactor technology offers a unique way to perform ultrafast, exothermic reactions, and allows the execution of reactions which proceed via highly unstable or even explosive intermediates. This Review discusses recent literature examples of continuous-flow organic synthesis where hazardous reactions or extreme process windows have been employed, with a focus on applications of relevance to the preparation of pharmaceuticals.

Continuous‐Flow Technology—A Tool for the Safe Manufacturing of Active Pharmaceutical Ingredients

50 % of reactions in the fine chemical/pharmaceutical industry could benefit from a continuous process based mainly on microreactor technology. However, the frequent presence of a solid phase still hinders the widespread application of such a technology as a multi-purpose solution. For small scale and pilot productions, speed in process R&D, as well as the avoidance of scale-up issues, are the main drivers. On the other hand, for large scale productions, a gain in yield and safety are the main motivations for the use of micoreactor technology. The gain in yield must be significant in order to cope with the increase in capital expenditure associated with the development of a new technology.

Microreactor Technology: A Revolution for the Fine Chemical and Pharmaceutical Industries?

Controlled autocatalytic nitration of phenol in a microreactor

Dibal-H Reduction of Methyl Butyrate into Butyraldehyde using Microreactors

The invention relates to the nitration of aromatic or heteroaromatic compounds, wherein an activated aromatic or heteroaromatic compound and a nitrating agent, in the presence, if desired, of a solvent, are mixed intensely in a microreactor, and wherein the proportion of the nitrating agent to the activated aromatic or heteroaromatic compound, the concentration of nitrating agent in the reaction mixture, and the temperature are selected at levels such that the nitration begins autocatalytically, and wherein the nitration product is obtained after leaving the microreactor and, if desired, after an after-reaction time outside the microreactor.

Nitration of activated aromatics in microreactors

Microreactor Technology: A Revolution for the Fine Chemical and Microreactor Technology: A Revolution for the Fine Chemical and Microreactor Technology: A Revolution for the Fine Chemical and Microreactor Technology: A Revolution for the Fine Chemical and Pharmaceutical Industries? Pharmaceutical Industries? Pharmaceutical Industries? Pharmaceutical Industries?

Laurent Ducry

Papers

Microreactor Technology: A Revolution for the Fine Chemical and Pharmaceutical Industries?

Controlled autocatalytic nitration of phenol in a microreactor

Dibal-H Reduction of Methyl Butyrate into Butyraldehyde using Microreactors

Nitration of activated aromatics in microreactors