Simulations of reaction equilibria in polymer systems - method development and applications

Project description:
Two-phase systems based on polyelectrolyte gels or coacervates are potential candidates for charge-based protein sequestration, while polymers modified by boronic acids are capable of sugar sensing. Their common feature is a chemical reaction inside the system, coupled to partitioning of solutes between the system and the bulk solution, illustrated in Fig.1. Experimental studies of such systems have long shown a deficit in theoretical support, partly due to the lack of suitable simulation methods.[1] However, we have recently introduced the Grand-reaction ensemble method which enables simulating reactive polymer systems in equilibrium with a reservoir.[2] Accordingly, within the current project, we will further develop this method and apply it to two-phase systems, addressing specific questions arising from experiments performed within the project, or raised by our external partners. This unique expertise in simulating reactive polymer systems will enable us to perform state-of-the-art simulations with a high level of chemical accuracy matched only by a few teams worldwide.

Fig.1: Schematic illustration of the partitioning of solutes between the bulk solution and reservoir, and the chemical reactions which occur in the system.

Job description:
The task of the postdoctoral researcher will be to further develop, implement and apply the G-RxMC method for simulating complex coacervates, reversible polymer gels and partitioning of solutes. Computer simulations will be used to predict their structure, stability and ability to sequestrate ions at various pH. Ultimately, the simulation predictions will be used to explain specific experiments or to design new smart experimental systems.

Features of an ideal candidate:

• Completed PhD or a fixed date of PhD defense before October 2020
• Good knowledge of English (FCE equivalent or better)
• Strong background in soft matter and statistical mechanics
• Experience with molecular simulation, programming and Linux

References:

1. J. Landsgesell, L. Nová, O. Rud, F. Uhlík, D. Sean, P. Hebbeker, C. Holm, P. Košvan. “Simulations of ionization equilibria in weak polyelectrolyte solutions and gels.” Soft Matter (2019), 15, 11551185 doi: 10.1039/C8SM02085J
2. J. Landsgesell, P. Hebbeker, O. Rud, R. Lunkad, P. Košovan, C. Holm “Grand-Reaction Method for Simulations of Ionization Equilibria Coupled to Ion Partitioning.” Macromolecules, (2020) 53, 8, 3007–3020 doi: 10.1021/acs.macromol.0c00260

How to submit the application:
Please send an email with a motivation letter, your professional CV and a list of publications to the project supervisor:
Dr. Peter Košovan
Soft Matter reasearch group
Department of Physical and Macromolecular Chemistry
Faculty of Science, Charles University
✉ Hlavova 2030, 128 43 Prague 2
e-mail: peter.kosovan@natur.cuni.cz
☎ +420-22195-1029

Eliglibility criteria:

• non Czech citizen
• completed PhD (a fixed date of PhD defense before October 2020 is also acceptable)
• less than 5 years from PhD graduation

Selection process:
Selection will be based on the relevance of candidates’ professional interests and experience, and excellence in research achievements.

Position duration, starting date and remuneration:
The position duration is 24 months, starting on January 1, 2021 and ending December 31, 2023. Standard gross monthly salary is approx. 2 400 € including health insurance and social insurance coverage. The job status is full-time - 40 hours per week.

Additional details of the funding scheme are provided on the web pages fo the rectorate