J. C. Dobrowolsk et al.
128
5.5.2.5 L-histidine
O
O
N
N
N
H
Scheme 8 (S)-amino-(1h-imidazol-2-yl)-acetic acid
VCD and ROA: Experiment and Calculations Beyond the early registrations
of C*h band vibrations in vCd spectra by the Nafie group [147–150], the vCd
spectra of L-histidine in water have been collected in water solution and in the form
of aqueous films with α-cyclodextrin (Fig. 5.14) [38].
the thorough computational investigations of Jalkanen et al. [154] on the vibrational spectroscopy of three amino acids in aqueous solution also devoted some attention to L-histidine. the authors demonstrated that, as for alanine, the supramolecular treatment of the first solvation sphere by at least four water molecules was
necessary to stabilise L-histidine zwitterions. the mono- and di- protonated histidine
zwitterions were considered to reproduce the vCd and RoA spectra.
A combined theoretical and experimental vCd, RoA as well as IR and Raman study of L-histidine in aqueous solution was done by deplazes et al. in 2008
[214]. Based on B3LYP/PCm/6-31g* calculations performed with the use of 13
water molecules, the authors verified previous findings regarding the kind and
conformation of species present in the solutions. the verification was based on
absorption IR and Raman spectra of L-histidine cations, zwitterions, and anions
measured at various ph levels in aqueous solution, and then applied to reproduce
the vCd and RoA intensities (Fig. 5.15).
Fig. 5.14 A film of L-histidine was obtained from a 200 μL solution of L-histidine-α-CD
(0.012 m) in h 2 O. The solution spectra of L-histidine were obtained at 0.26 M using a 15 μm path
length demountable cell. Solution vCd spectra were obtained with 6 h of data collection time.
(Reproduced from Ref. [38] with kind permission of Society of Applied Spectroscopy)
128
5.5.2.5 L-histidine
O
O
N
N
N
H
Scheme 8 (S)-amino-(1h-imidazol-2-yl)-acetic acid
VCD and ROA: Experiment and Calculations Beyond the early registrations
of C*h band vibrations in vCd spectra by the Nafie group [147–150], the vCd
spectra of L-histidine in water have been collected in water solution and in the form
of aqueous films with α-cyclodextrin (Fig. 5.14) [38].
the thorough computational investigations of Jalkanen et al. [154] on the vibrational spectroscopy of three amino acids in aqueous solution also devoted some attention to L-histidine. the authors demonstrated that, as for alanine, the supramolecular treatment of the first solvation sphere by at least four water molecules was
necessary to stabilise L-histidine zwitterions. the mono- and di- protonated histidine
zwitterions were considered to reproduce the vCd and RoA spectra.
A combined theoretical and experimental vCd, RoA as well as IR and Raman study of L-histidine in aqueous solution was done by deplazes et al. in 2008
[214]. Based on B3LYP/PCm/6-31g* calculations performed with the use of 13
water molecules, the authors verified previous findings regarding the kind and
conformation of species present in the solutions. the verification was based on
absorption IR and Raman spectra of L-histidine cations, zwitterions, and anions
measured at various ph levels in aqueous solution, and then applied to reproduce
the vCd and RoA intensities (Fig. 5.15).
Fig. 5.14 A film of L-histidine was obtained from a 200 μL solution of L-histidine-α-CD
(0.012 m) in h 2 O. The solution spectra of L-histidine were obtained at 0.26 M using a 15 μm path
length demountable cell. Solution vCd spectra were obtained with 6 h of data collection time.
(Reproduced from Ref. [38] with kind permission of Society of Applied Spectroscopy)