The Transition of Cell-Free Protein Synthesis towards Microfluidic Systems

Abstract

Despite the tremendous advances in recombinant biotechnology throughout recent years, the currently employed methods for producing, harvesting, and purifying recombinant proteins present some significant limitations. Specifically, the synthesis of these proteins of interest, whether it is for industrial or pharmaceutical purposes, is usually performed in host organisms such E. coli that can require extensive preparation, upkeep, and purification. Additionally, it is sometimes impossible to express proteins of interest in these host organisms due to their cytotoxic nature or improper post-translational transformations. Ultimately, these limitations hinder the production of valuable proteins in yields that would satisfy market needs. This most often translates into high market prices, especially for pharmaceutical proteins, but also the inability to rapidly produce novel biomolecules with beneficial properties.

This bachelor’s thesis explores novel possibilities of synthesizing proteins of interest to overcome the aforementioned limitations. Some of the basic principles of cellular protein pro-duction are first presented to establish and highlight the required biomolecular mechanisms for protein synthesis. The currently used cell-based protein production processes are then pre-sented in order to compare them with cell-free processes. Some of the covered examples of cell-free expression systems are taken from commercially available sources that are proved capable of bypassing the limitations of recombinant cell cultures. We can also attest through these examples that cell-free solutions are especially suitable for research purposes. Howev-er, they also present issues that reduce their effectiveness. Notably, limited amounts of rea-gents and the simultaneous occurrence of different reactions in the same container raise is-sues regarding reusability, yields and controllability.

As an answer to these concerns, some experimental microfluidic platforms targeting cell-free protein synthesis (CFPS) have been developed in recent years. The field of microfluidics opens a window towards multiple possibilities for better performance. Multiple studies show-casing the benefits of microfluidics in CPFS have been performed, some of which have shown promising results. It is only expected that studies revolving around CFPS on microfluidic chips and devices utilizing their concepts will only increase in number during the years to come.