Synthesis and Characterization of Amino Acid Based Deep Eutectic Solvents by IR Spectroscopy and Principal Component Analysis
Disciplines
Analytical Chemistry | Environmental Chemistry
Abstract (300 words maximum)
Deep Eutectic Solvents (DES) are emerging environmentally friendly solvents having applications towards various sectors including electrochemistry, biocatalysis, organic synthesis, pharmaceutical industries etc. The attractive properties of DESs, i.e. renewable, biodegradable, inexpensive, nontoxic etc. make them appealing to researchers as alternative to traditional hazardous solvents. DESs are prepared by mixing two or more components including a hydrogen bond donor (HBD) and a hydrogen bond acceptor (HBA), at a certain ratio with continuous stirring and constant temperature. The various nonbonding interactions, such as dipole-dipole, hydrogen bond, hydrophobic interactions and Van der Waals forces etc. among the HBA and HBD are key factors for depression of melting temperature and hence the DES formation. Among different types of DESs i.e. metal halide, nonionic, therapeutic etc., amino acid-based DESs have become popular due to their impact on protein structure and charge reducing capabilities in native mass spectrometry. The focus of this study was to synthesize different amino acid based DESs by mixing Arginine, Histidine etc. as HBA with glycerol, ethylene glycol, lactic acid etc. as HBD at certain ratio. The mixing was conducted in a glass beaker with continuous stirring at a rate of 500-700 rpm maintaining temperature about 40 °C-100 °C. After preparation the DESs were characterized by ATR-FTIR spectrophotometer to compare the presence and shift of major functional groups in individual components and prepared DES. The origin pro (2024) was used for graphical representation and Principal component Analysis (PCA) of IR data of DESs. Among 9 prepared DESs, Histidine and Lactic acid DES (1:9) and methyl-triphenyl-phosphonium bromide and ethylene glycol (1:5) found more homogenous, clear liquid at room temperature. The functional groups were well distinguished in IR spectra and PCA graph. However, some DESs were very viscous, yellowish color whereas some did not mix at all and were not suitable for IR analysis.
Academic department under which the project should be listed
CSM - Chemistry and Biochemistry
Primary Investigator (PI) Name
Mohammad A. Halim
Synthesis and Characterization of Amino Acid Based Deep Eutectic Solvents by IR Spectroscopy and Principal Component Analysis
Deep Eutectic Solvents (DES) are emerging environmentally friendly solvents having applications towards various sectors including electrochemistry, biocatalysis, organic synthesis, pharmaceutical industries etc. The attractive properties of DESs, i.e. renewable, biodegradable, inexpensive, nontoxic etc. make them appealing to researchers as alternative to traditional hazardous solvents. DESs are prepared by mixing two or more components including a hydrogen bond donor (HBD) and a hydrogen bond acceptor (HBA), at a certain ratio with continuous stirring and constant temperature. The various nonbonding interactions, such as dipole-dipole, hydrogen bond, hydrophobic interactions and Van der Waals forces etc. among the HBA and HBD are key factors for depression of melting temperature and hence the DES formation. Among different types of DESs i.e. metal halide, nonionic, therapeutic etc., amino acid-based DESs have become popular due to their impact on protein structure and charge reducing capabilities in native mass spectrometry. The focus of this study was to synthesize different amino acid based DESs by mixing Arginine, Histidine etc. as HBA with glycerol, ethylene glycol, lactic acid etc. as HBD at certain ratio. The mixing was conducted in a glass beaker with continuous stirring at a rate of 500-700 rpm maintaining temperature about 40 °C-100 °C. After preparation the DESs were characterized by ATR-FTIR spectrophotometer to compare the presence and shift of major functional groups in individual components and prepared DES. The origin pro (2024) was used for graphical representation and Principal component Analysis (PCA) of IR data of DESs. Among 9 prepared DESs, Histidine and Lactic acid DES (1:9) and methyl-triphenyl-phosphonium bromide and ethylene glycol (1:5) found more homogenous, clear liquid at room temperature. The functional groups were well distinguished in IR spectra and PCA graph. However, some DESs were very viscous, yellowish color whereas some did not mix at all and were not suitable for IR analysis.