Optical properties of Meloxicam in the far-infrared spectral region

2018-08-17
Aytekin, Yusuf Samet
Zaczek, Adam
Korter, Timothy M.
Heilweil, Edwin J.
Esentürk, Okan
One of the most commonly used nonsteroidal anti-inflammatory active pharmaceutical ingredient called Meloxicam has been characterized spectroscopically both by Terahertz (THz) time domain spectroscopy (THz-TDS) and by Fourier Transform Infrared (FTIR) spectroscopy in far-IR regions of electromagnetic spectrum; 0.2 THz-20 THz. While many relatively sharp features are observed in the far-IR range between 2 THz-20 THz as expected for being an organic substance, very distinct and relatively strong absorption bands are also observed at 1.00, 1.66, 2.07 and 2.57 THz in the THz range. These well separated, defined, and fairly strong spectral features can be used for discrimination and quantification of Meloxicam in drug analysis. Frequency dependent refractive index of the drug was determined in a range of 0.2 THz-2.7 THz, where an almost constant index was observed with an average index of 1.75. Powder XRD, and solid-state Density Functional Theory (SS-DFT) calculations were utilized to determine the crystalline form of the Meloxicam sample in its enolic crystalline form. Single molecule DFT calculations were also performed in all four possible structures of Meloxicam. In addition, the capability of THz waves transmission through common packaging materials is demonstrated for possibility of future on-site analysis. The results suggest that drug analysis will be possible to perform not only at every stage of manufacturing without destruction but also directly at the shelf of a market after development of portable THz technologies.
CHEMICAL PHYSICS

Suggestions

Vibrational spectroscopy of hydrogen-bonded systems: Six-dimensional simulation of the IR spectrum of F-(H2O) complex
Toffolı, Danıele; Sparta, Manuel; Christiansen, Ove (Elsevier BV, 2011-06-24)
The vibrational dynamics of the F-(H2O) complex is studied using highly accurate six-dimensional molecular potential energy and dipole moment surfaces calculated at the CCSD (T)/cc-pVQZ and CCSD (T)/augcc-pVTZ levels with a multiresolution approach. The extent of mode-coupling is investigated with full vibrational configuration-interaction (FVCI) calculations. Coriolis coupling effects are also included with the aim to obtain quantitative agreement with the experimental data available. The vibrational absor...
Nonlinear absorption behaviors of filled and unfilled d shell metal complexes of 5, 10, 15, 20-tetrakis(4-hydroxyphenyl)porphyrin
Dogan, N.; Dumanogullari, F. M.; HAYVALI, MUSTAFA; YILMAZ, HAMZA; Kurum, U.; YAĞLIOĞLU, HALİME GÜL; ELMALI, Ayhan (Elsevier BV, 2011-05-27)
We study nonlinear absorption behaviors of 5, 10, 15, 20-tetrakis(4-hydroxyphenyl)porphyrins with the central metal ions: Zn(2+), Ni(2+), Co(2+), and Fe(3+) by open aperture Z-scan technique with 65 ps or 4 ns pulse duration. For 65 ps pulse duration the filled d shell compounds exhibit nonlinear absorption while the unfilled d shell compounds exhibit saturable absorption. For 4 ns pulse duration Ni, Co and Fe compounds exhibit nonlinear absorption at high fluence while Ni compound exhibits saturable absorp...
Phase behavior of beta-D galactose pentaacetate-carbon dioxide binary system
Dilek Hacıhabiboğlu, Çerağ; Gulari, Esin (Elsevier BV, 2006-01-31)
Phase behavior of beta-D galactose pentaacetate-carbon dioxide binary system is investigated by dew-point and bubble-point measurements conducted in a high pressure variable volume sapphire cell. The phase envelope for solutions of beta-D galactose pentaacetate in supercritical M is obtained for beta-D galactose pentaacetate concentrations between 2 and 26 wt%, and for the temperature range of 308-323 K. The system exhibits lower critical solution temperature (LCST) behavior and high solubility of beta-D ga...
Optical and vibrational properties of nickel integrated germanium Zintl ion clusters
Ogun, Esra; Esentürk, Okan; Nalbant Esentürk, Emren (Elsevier BV, 2019-05-01)
Vibrational and optical properties of Ni-Ge clusters ([Ni2Ge9(PPh3)](2-), [Ni6Ge13(CO)(5)](4-)) have been investigated via UV-Vis, FTIR, and Fluorescence spectroscopies. Moreover, frequency and time-dependent (TD) electronic transition calculations have been performed to better characterize experimental findings, due to the scarcity of vibrational and optical spectroscopic studies on these type of clusters in the literature. UV-Vis spectroscopic analyses demonstrate a broad absorption band, with a maximum a...
Associative behaviour and effect of functional groups on the fluorescence of graphene oxide
Ozcan, Sefika; Vempati, Sesha; Çırpan, Ali; Uyar, Tamer (Royal Society of Chemistry (RSC), 2018-01-01)
We have juxtaposed the structural, vibrational and emission properties of graphene oxide (GO) with various degrees of reduction with and without a model dispersant, unveiling a strong associative behavior between GO sheets and the influence of H-bonds. The interlayer spacings are similar to 0.84 and 0.78 nm for the as prepared and reduced samples. -OH groups are predominantly effected by the photo-thermal reduction. Also we note some regeneration of > C=O and -COOH groups in reduced samples. Clear changes t...
Citation Formats
Y. S. Aytekin, A. Zaczek, T. M. Korter, E. J. Heilweil, and O. Esentürk, “Optical properties of Meloxicam in the far-infrared spectral region,” CHEMICAL PHYSICS, pp. 36–43, 2018, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/36838.