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Marciniec B. Kozak M. Wachowski L. Ogrodowczyk M. 《Journal of Thermal Analysis and Calorimetry》2003,73(2):473-485
The effect of ionising radiation (15-100 kGy) on the physico-chemical properties of 6 steroid derivatives in solid state (Hydrocortisone,
Hydrocortisone acetate, Prednisolone, Prednisolone acetate, Dexamethasone and Fludrocortisone acetate) was studied by differential
scanning calorimetry (DSC), differential thermal analysis (DTA), scanning electron microscopy (SEM), UV spectrophotometry,
high-performance liquid chromatography (HPLC), X-ray powder diffraction and polarimetry. DSC and DTA results revealed that
the irradiated compounds undergo phase transitions at lower temperatures, show lower melting points and lower enthalpy of
the melting process their non-irradiated analogues. The results of HPLC measurements proved a loss in the active substance
content after irradiation ranging from 0.5 to 2.88%. No significant effect of irradiation was detected by the UV spectrophotometry
or polarimetry in the course of the UV spectrum, absorbancy or optical rotation, as well as in the SEM photographs and X-ray
patterns. For some compounds studied a correlation was found between the irradiation dose and the shifts in DSC curves and
the loss of content determined by the HPLC method. Similar, but not so much pronounced relations were established in or earlier
studies of the derivatives of nitroimidazole and 1,4-dihydropyridine. In general the results have shown relatively high radiochemical
stability of the compounds studied and have proved that the DSC method is a sensitive detector of irradiation-caused changes
in drugs in solid phase.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
2.
Barbara Marciniec M. Kozak M. Naskrent K. Dettlaff M. Ogrodowczyk M. Stawny L. Wachowski 《Journal of Thermal Analysis and Calorimetry》2007,88(2):337-342
Four imidazoline
derivatives: antazoline (AN), naphazoline (NN), tymazoline (TM), xylometazoline
(XM), in the form of hydrochlorides in solid phase have been subjected to
high energy e-beam irradiation from an accelerator (~10 MeV) at a dose varied
from 25 to 200 kGy. The effects of the irradiation have been assessed by DSC,
X-ray diffraction, FTIR, EPR and TLC.
The standard sterilisation
dose of 25 kGy has been found to produce changes in the properties of one
derivative (XM), two other ones (AN and TM) have been found sensitive to doses
>100 kGy, whereas NN has been resistant to irradiation in the whole range
studied (25–200 kGy). EPR results indicated that the changes taking
place in the therapeutic substances studied are related to radical formation.
The irradiation induced changes in colour, a decrease or increase in the melting
point, changes in the XRD pattern, small changes in the shape of FTIR peaks
and the presence of radiolysis products. The XM compounds cannot be sterilised
by irradiation because of the radiation induced changes in its physico-chemical
properties. 相似文献
3.
Magdalena Ogrodowczyk Barbara Marciniec Piotr Kachlicki 《Central European Journal of Chemistry》2014,12(1):60-66
Pindolol ((2RS)-(1-(1H-indol-4-iloxy)-3- [(1-metyloetylo)amino]-2-propanol) in substantia was exposed to ionising radiation emitted by high energy electrons from an accelerator, in the standard sterilisation dose of 25 kGy and in higher doses from the range 50–400 kGy. The effects of irradiation were checked by spectrometric methods (UV, MS, FT-IR, EPR) and hyphenated methods (HPLC-MS) and the results were referred to those obtained for non-irradiated sample. EPR results indicated the presence of free radicals in irradiated samples, in the amount of 1.36 × 1016 spin g?1 for 25 kGy and 3.70×1016 spin g?1 for 400 kGy. The loss of pindolol content determined by HPLC was 1.34% after irradiation with 400 kGy, while the radiolytic yield of the total radiolysis for this dose of irradiation was 2.69×107 mol J?1. By means of HPLC-MS it was possible to separate and identify one product of radiolytic decomposition, which probably is 2-((R)-3-(1H-indol-4-yloxy)-2-hydroxypropylamino)propan-1-ol formed upon oxidation. In the range of sterilisation doses (25–50 kGy), pindolol was found to show high radiochemical stability and would probably be safely sterilised by the standard dose of 25 kGy. 相似文献
4.
Magdalena Ogrodowczyk Katarzyna Dettlaff Waldemar Bednarski Barbara Ćwiertnia Maciej Stawny Grzegorz Spólnik Juliusz Adamski Witold Danikiewicz 《Chemical Papers》2018,72(2):349-357
Nadolol ((2R*,3S*)-5-{[(2R*)-3-(tert-butylamino)-2-hydroxypropyl]oxy}-1,2,3,4 tetrahydronaphthalene-2,3-diol) in substantia was exposed to ionizing radiation generated by a beam of high-energy electrons in an accelerator, in the standard sterilisation dose of 25 kGy and in higher doses of 50 ? 400 kGy. The irradiated and non-irradiated (control) samples were analysed by the infrared spectrophotometry, electron paramagnetic resonance, differential scanning calorimetry (DSC) and ultra-high performance liquid chromatography coupled with mass spectrometry (UHPLC–MS). The irradiated samples were found to contain free radicals in concentrations much higher than that observed for the other irradiated β-blockers. On the basis of UHPLC–MS results, it was possible to establish structures of 11 compounds of the impurities and/or products of nadolol decomposition. The main product of radiodegradation was concluded to be formed as a result of abstraction of the hydroxyl group and aromatization of the tetrahydronaphthalene ring. The results of DSC measurements confirmed the presence of radiolysis products in the irradiated samples of nadolol. A shift of the endothermic peak corresponding to melting towards lower temperatures (by 4.4 °C at the dose of 400 kGy) was directly proportional to the doses of radiation used, which permits concluding that this method is sensitive and suitable for evaluation of radiodegradation of nadolol in solid phase. 相似文献
5.
Marciniec B. Kozak M. Ogrodowczyk M. 《Journal of Thermal Analysis and Calorimetry》2004,77(2):581-596
The effect of sterilisation by irradiation has been studied for the seven most often used in medicine derivatives of 1,4-dihydropyridine
(nifedipine, nisoldipine, nicardipine, nitrendipine, nimodipine, felodipine and amlodipine). The sterilisation was performed
for the compounds in the solid phase with an electron beam of the energy 10 MeV, at room temperature, using the irradiation
doses from 20 to 400 kGy. The effects of the irradiation were studied by the methods SEM, DSC, XRD and TLC. The sterilisation
with doses 20-100 kGy was found to cause no changes in the physico-chemical properties of the compounds, while the irradiation
with higher doses (200-400 kGy) was found to induce changes in the colour, DSC spectrum and TLC picture. As follows from the
TLC results, the main product of radiolysis of the compounds studied was a pyridine nitrozoderivative, which indicates the
same mechanism of decomposition as in the process of photodegradation. The results prove that the 1,4-dihydropyridine derivatives
being highly sensitive to visible and UV radiation are generally resistant to ionising radiation and thus can be subjected
to sterilisation by irradiation.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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