Micro-chemical synthesis of molecular probes on an electronic microfluidic device

Fluorescent d-amino acids (FDAAs) are molecular probes that are widely used for labelling the peptidoglycan layer of bacteria. When added to growing cells they are incorporated into the stem peptide by a transpeptidase reaction, allowing the timing and localization of peptidoglycan synthesis to be determined by fluorescence microscopy. Herein we describe the chemical synthesis of an OregonGreen488-labelled FDAA (OGDA). We also demonstrate that OGDA can be efficiently incorporated into the PG of Gram-positive and some Gram-negative bacteria, and imaged by super-resolution stimulated emission depletion (STED) nanoscopy at a resolution well below 100 nm.

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Nonenzymatic synthesis of anomerically pure, mannosyl-based molecular probes for scramblase identification studies

Beilstein Journal of Organic Chemistry ◽

10.3762/bjoc.16.145 ◽

2020 ◽

Vol 16 ◽

pp. 1732-1739

Author(s):

Giovanni Picca ◽

Markus Probst ◽

Simon M Langenegger ◽

Oleg Khorev ◽

Peter Bütikofer ◽

...

Keyword(s):

Membrane Proteins ◽

Chemical Synthesis ◽

Molecular Probes ◽

Protein Glycosylation ◽

Pure Form ◽

Short Chain ◽

Biological Pathway ◽

Naturally Occurring ◽

Phosphoramidite Chemistry ◽

Straightforward Approach

The chemical synthesis of molecular probes to identify and study membrane proteins involved in the biological pathway of protein glycosylation is described. Two short-chain glycolipid analogs that mimic the naturally occurring substrate mannosyl phosphoryl dolichol exhibit either photoreactive and clickable properties or allow the use of a fluorescence readout. Both probes consist of a hydrophilic mannose headgroup that is linked to a citronellol derivative via a phosphodiester bridge. Moreover, a novel phosphoramidite chemistry-based method offers a straightforward approach for the non-enzymatic incorporation of the saccharide moiety in an anomerically pure form.

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High diversity droplet microfluidic libraries generated with a commercial liquid spotter

Scientific Reports ◽

10.1038/s41598-021-83865-y ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Jesse Q. Zhang ◽

Christian A. Siltanen ◽

Ata Dolatmoradi ◽

Chen Sun ◽

Kai-Chun Chang ◽

...

Keyword(s):

Chemical Synthesis ◽

Microfluidic Device ◽

Droplet Microfluidics ◽

Droplet Generator ◽

Manual Operation ◽

Multiplexed Pcr ◽

User Intervention ◽

High Diversity

AbstractDroplet libraries consisting of many reagents encapsulated in separate droplets are necessary for applications of microfluidics, including combinatorial chemical synthesis, DNA-encoded libraries, and massively multiplexed PCR. However, existing approaches for generating them are laborious and impractical. Here, we describe an automated approach using a commercial array spotter. The approach can controllably emulsify hundreds of different reagents in a fraction of the time of manual operation of a microfluidic device, and without any user intervention. We demonstrate that the droplets produced by the spotter are similarly uniform to those produced by microfluidics and automate the generation of a ~ 2 mL emulsion containing 192 different reagents in ~ 4 h. The ease with which it can generate high diversity droplet libraries should make combinatorial applications more feasible in droplet microfluidics. Moreover, the instrument serves as an automated droplet generator, allowing execution of droplet reactions without microfluidic expertise.

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Development of Microdroplet Generation Method for Organic Solvents Used in Chemical Synthesis

Molecules ◽

10.3390/molecules25225360 ◽

2020 ◽

Vol 25 (22) ◽

pp. 5360

Author(s):

Shohei Hattori ◽

Chenghe Tang ◽

Daiki Tanaka ◽

Dong Hyun Yoon ◽

Yoshito Nozaki ◽

...

Keyword(s):

Chemical Synthesis ◽

Organic Solvents ◽

Chemical Reactions ◽

Microfluidic Device ◽

Microfluidic Devices ◽

Continuous Phase ◽

Immiscible Liquid ◽

Droplet Generation ◽

Scaling Effects ◽

Reaction Field

Recently, chemical operations with microfluidic devices, especially droplet-based operations, have attracted considerable attention because they can provide an isolated small-volume reaction field. However, analysis of these operations has been limited mostly to aqueous-phase reactions in water droplets due to device material restrictions. In this study, we have successfully demonstrated droplet formation of five common organic solvents frequently used in chemical synthesis by using a simple silicon/glass-based microfluidic device. When an immiscible liquid with surfactant was used as the continuous phase, the organic solvent formed droplets similar to water-in-oil droplets in the device. In contrast to conventional microfluidic devices composed of resins, which are susceptible to swelling in organic solvents, the developed microfluidic device did not undergo swelling owing to the high chemical resistance of the constituent materials. Therefore, the device has potential applications for various chemical reactions involving organic solvents. Furthermore, this droplet generation device enabled control of droplet size by adjusting the liquid flow rate. The droplet generation method proposed in this work will contribute to the study of organic reactions in microdroplets and will be useful for evaluating scaling effects in various chemical reactions.

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