In the present work, the thermal behavior of Lornoxicam drug was studied under oxidizing (air) and pyrolysis (N2) atmospheres using simultaneous thermogravimetry and differential scanning calorimetry (TG-DSC), differential scanning calorimetry (DSC), Hot Stage Microscopy (HSM) and Evolved Gas Analysis (EGA) in the form of thermogravimetry coupled to infrared spectroscopy (TG-FTIR) and mass spectrometry (TG-MS). The thermal degradation product formed at different temperatures were examined using liquid chromatography coupled to mass spectrometry (LC-MS) and Powder X-Ray Diffraction (PXRD). The thermal study showed that the drug does not melt, partially amorphized on heating, it is thermally stable to 205 °C and undergoes thermal decomposition in two overlapping mass loss steps. Furthermore, the DSC and MS techniques suggest that thermal degradation processes are very complex, which occur with the release of gaseous products HCN, SO2, COS, CO2, N2O and CO and formation of three intermediate in the thermal residue.

Heavy trivalent lanthanides and yttrium picolinates were synthesized by complexation of basic rare-earth metal carbonates with an aqueous solution of picolinic acid. The novel compounds were obtained with the general formula Ln(L)3•nH2O, where L is picolinate and n= 1.5 H2O (Dy, Ho, Yb, Lu and Y), 2 H2O (Tb and Tm) and 2.5 H2O (Er). The stoichiometry of the complexes was calculated through mass losses found using thermogravimetry (TG), complexometry and elemental analysis (EA). The thermal behavior in oxidative and pyrolytic atmospheres of the compounds was analyzed by simultaneous thermogravimetry -differential scanning calorimetry (TG-DSC). The gaseous products of the pyrolysis were determined throughout by monitoring the evolved species using TG-DSC, Fourier transform infrared spectroscopy (TG-DSC-FTIR), hot-stage microscopy mass spectrometry (HSM-MS), and gas chromatography-mass spectrometry (GC-MS). The obtained results validated mass loss assignments made using the TG curves. However, gaseous product analysis indicates the degradation processes are more complex than the thermoanalytical techniques suggest alone. This study used a GC-MS technique to identify the condensed gaseous products obtained during the second step of the thermal degradation of the picolinate complexes. The analysis of the symmetric and asymmetric stretching frequencies of the carboxylate group in the FTIR spectra showed a monodentate bonding mode. The compounds were obtained in the amorphous state, as indicated by the powder X-ray diffractometry (PXRD) data.

Lornoxicam metal complexes [M(Lor)2(OH2)2]•nH2O, where M represents the bivalent transition metals (Mn(II) to Zn(II)), Lor is Lornoxicam ligand and n = 2.0 or 2.5 were synthesized. The compounds were characterized by elemental analysis (EA), powder X-ray diffraction (PXRD), infrared spectroscopy (FTIR), simultaneous thermogravimetry and differential scanning calorimetry (TG-DSC) under oxidizing and pyrolysis conditions, differential scanning calorimetry (DSC), hot-stage microscopy (HSM) and evolved gas analysis (EGA) by coupled hot-stage microscopy (HSM-MS) and Fourier transform infrared (TG−FTIR). Regardless of the atmosphere, the thermal stability and thermal behavior up to the first two mass loss steps of the anhydrous compound were similar, only differing significantly in the last steps. The main gaseous products released * Corresponding author.

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