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Ring-opening polymerization in carnosine under pressure
Chitra Murli1, A K Mishra, Susy Thomas
1High Pressure and Synchrotron Radiation Physics Division, Bhabha Atomic Research Centre, Mumbai, India. cmurli@barc.gov.in
The Journal of Physical Chemistry. B
|March 30, 2012
Summary
High pressure experiments reveal carnosine (a dipeptide) undergoes ring-opening polymerization of its imidazole ring above 2.8 GPa. The resulting polymer remains stable when pressure is released.
Area of Science:
- Biochemistry
- Materials Science
- Physical Chemistry
Background:
- Carnosine is a naturally occurring dipeptide composed of L-histidine and β-alanine.
- Understanding the behavior of biomolecules under extreme conditions is crucial for various scientific fields.
Purpose of the Study:
- To investigate the effects of high pressure on the molecular structure and potential transformations of carnosine.
- To explore the pressure-induced polymerization of carnosine and its stability.
Main Methods:
- High pressure Raman scattering experiments were conducted on carnosine.
- Varying pressure conditions were applied, ranging up to 12 GPa.
- Raman spectra were analyzed to identify structural changes and polymerization.
Main Results:
- Pressure-induced ring-opening polymerization of the imidazole ring in carnosine was observed.
- Polymerization initiated at approximately 2.8 GPa, with significant polymerization occurring by 12 GPa.
- The polymerized form of carnosine did not exhibit any Raman modes of the ambient phase upon release of pressure.
Conclusions:
- Carnosine can undergo irreversible polymerization under high pressure conditions.
- The imidazole ring of carnosine is susceptible to pressure-induced ring-opening polymerization.
- The resulting polymer is stable at ambient conditions, suggesting potential for novel material applications.
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