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1.
Marciniec B Stawny M Kozak M Naskrent M 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2008,69(3):865-870
The effect of ionising radiation, applied in the form of an electron beam, in the doses of 25, 100 and 400 kGy on the physical and chemical properties of thiamphenicol in solid phase has been studied by organoleptic analysis (form, colour, smell, solubility, clarity) and spectroscopic methods (UV, IR, EPR), chromatography (TLC), SEM observations, X-ray diffraction, polarimetry and thermal method (DSC). The above-discussed results have proved that on irradiation with a dose of 25 kGy no significant changes appear in thiamphenicol, apart from the formation of free radicals of the lifetime of over 352 days. On irradiation with much higher doses (100 and 400 kGy) no changes were observed in the IR spectra but the UV line intensities slightly increased at lambda(max)=266 and 273 nm, the colour of the powder changed, the radiolysis products appeared as detected by TLC, changes were also observed in the XRD, SEM pictures, the melting point values (DSC) and optical rotation. On the basis of DSC results a linear relation was found between the irradiation dose and the decrease in the melting point and increase in the enthalpy of melting, characterised by high correlation coefficients of r=0.9839 and 0.9622, respectively. Moreover, a linear relation was established between the optical rotation angle and the irradiation dose, alpha(D) ( degrees )=f(dose), characterised by the correlation coefficient r=0.9874. The results obtained indicate that thiamphenicol can be safely subjected to radiation sterilization by the standard dose of 25 kGy. 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.
Barbara Marciniec Katarzyna Dettlaff Marek Naskrent Zuzanna Pietralik Maciej Kozak 《Journal of Thermal Analysis and Calorimetry》2012,108(1):33-40
The effect of ionising radiation on the physico-chemical properties of disulfiram (Antabuse, Esperal, bisdiethylthiocarbamoil
disulphide) has been studied by DSC, FTIR, EPR, MS, TLC and HPLC. Sterilisation was carried out in the solid state, at room
temperature and normal air humidity using the electron beam of 9.96 Mev from accelerator. All the measurements were made simultaneously
for the irradiated and nonirradiated substance. It has been found that the drug studied in solid phase when subjected to an
electron beam corresponding to the irradiation in the doses 10–100 kGy shows the presence of free radicals (EPR), and a change
in colour from white to pale green-grey that disappears after solution in water or methanol. After the irradiation with the
dose of 100 kGy, its melting point and enthalpy slightly decreased. Also the content of the active substance decreases (HPLC
−1.5%, UV −3.6%, iodometric titration method −2.7%) and trace amounts of the radiolysis products appear (HPLC). The substance
irradiated with the doses 10–50 kGy does not show changes in the melting point, in the content and presence of the radiolysis
products. The EPR results have shown that free radicals disappear after about a year and the discolouring disappears with
them. The results of this study have shown that disulfiram can be subjected to sterilisation by irradiation with no deterioration
of its physico-chemical properties, but a long time of storage needed to remove free radicals and discolouration questions
the economic justification for this type of sterilisation. 相似文献
4.
Barbara Marciniec M. Stawny Magdalena Hofman M. Naskrent 《Journal of Thermal Analysis and Calorimetry》2008,93(3):733-737
The study has been undertaken to check the effect of ionising radiation on the physical and chemical properties of florfenicol,
an antibiotic of a wide range of antibacterial activity. The solid-state samples were subjected to an electron beam generated
by accelerator corresponding to the doses of 25, 100 and 400 kGy, and the effect of the exposure was analysed by the methods
not requiring changes in the state (with no preliminary treatment), such as SEM, DSC, FTIR, XRD, EPR and HPLC.
Florfenicol irradiated with a dose of 25 kGy has not changed the form or colour, however, a small increase in intensity of
some absorption bands in the FTIR spectrum and of some peaks in the XRD pattern, a decrease in the melting point by 0.6°C,
the appearance of free radicals and a loss in the FF content within the error of the method (0.91%) have been observed. After
irradiation with greater doses (100 and 400 kGy) the changes have intensified, yellow discolouration appeared and the loss
of FF content has increased to 6.39%. As follows from the results, the compound studied in solid-state undergoes radiolysis
after e-beam irradiation in the doses ≥25 kGy, but lower doses (15–20 kGy) can be applied for its decontamination or sterilization
with no adverse effect on its physico-chemical properties. 相似文献
5.
B. Marciniec M. Kozak M. Naskrent M. Hofman K. Dettlaff M. Stawny 《Journal of Thermal Analysis and Calorimetry》2010,100(1):261-267
The effect of ionising radiation on the physico-chemical properties of salts of three alkaloids has been studied: codeine
phosphate (COD), papaverine hydrochloride (PAP) and pilocarpine hydrochloride (PIL). These compounds in the solid state were
irradiated with an e-beam of the energy of 9.96 MeV to achieve doses ranging from 25 to 400 kGy, and then they were subjected
to organoleptic analysis, thermal analysis (differential scanning calorimetry, DSC), electron resonance (EPR) spectroscopy,
scanning electron microscopy observations and X-ray diffraction study. The most informative were the results provided by the
EPR and DSC methods. The EPR spectra revealed the presence of long-lived radicals whose concentration was directly proportional
to the dose of irradiation for all the compounds studied. (PIL 2.14 × 1016 spin/g, COD 6.85 × 1015 spin/g, PAP 2.50 × 1014 spin/g—for the dose of 100 kGy). The DSC results revealed a decrease in the melting point by 5.9 °C for COD and by 0.8 °C
for PIL after irradiation with 200 kGy, which is indicative of products of radiolysis, of which at least one is non-white,
and changes the colour of the compounds. PAP, for which no decrease in the melting point and no colour change was observed
and for which the concentration of free radicals was the lowest, was found to be most stable from among the compounds studied.
It will probably be suitable for radiation sterilisation. The other two compounds COD and PIL show much lower radiochemical
stability and should be subjected to more detailed examination to establish the mechanism of radiolysis and the possibility
of radiation sterilisation. Our results have confirmed the earlier reports on high radiochemical stability of PAP, but do
not confirm the resistance to ionising radiation of COD and PIL. 相似文献
6.
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
7.
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
8.
Teruyuki Hakoda Akihiko Shimada Kanae Matsumoto Koichi Hirota 《Plasma Chemistry and Plasma Processing》2009,29(1):69-78
Electron beam (EB) technology has an advantage for treating dilute environmental pollutants in gases due to high-density population
of active species such as radicals and atoms. In general, OH radicals play an important role of initiating the decomposition
and removal of such pollutants. It is quite important to understand the behavior of OH radical production for the development
of efficient decomposition/removal processes and the comparison with other purification methods. The number of OH radicals
produced in humid N2 at doses of 2.0–10.0 kGy with dose rates of 0.17–2.55 kGy/s under 1-MeV EB irradiation was indirectly determined using an
index of oxidation of CO to CO2, which has been used in atmospheric chemistry. An experiment under conditions where all OH radicals produced react with CO
demonstrated that the concentration of CO2 increased linearly with doses of 0–10 kGy, and the G(OH) was estimated as 4.90. 相似文献
9.
Use of some organic dyes in gamma irradiation dose determination 总被引:1,自引:0,他引:1
In the present work, the radiation-induced color bleaching of Remazol brilliant blue (RBB), Wegocet orange (WO), Methyl green
(Me G) and Thioflavine S (Th S) dyes solutions was studied. Solutions of these dyes in different solvents were found to obey
Beer’s law within certain concentration levels. The % color bleaching occurring in different dye solutions on using different
gamma irradiation doses was determined and the data obtained showed the existence of good linear relationships among them
in the four dye systems used. The linear sections lines were used as calibration curves for evaluating unknown gamma irradiation
doses. From the obtained results, it was concluded that RBB in water, WO in ethanol, Me G in butanol and Th S in 60% ethanol–water
mixture could be used for dose evaluation within the dose ranges 5–25 kGy for RBB, 20–90 kGy for WO, 10–70 kGy for Me G and
5–160 kGy for Th S. The sensitivity of the systems towards gamma radiations has been also reported. 相似文献
10.
Summary Different γ-irradiated chloramphenicol (CAP) samples were screened for impurities by recording melting point, solubility,
pH and occurrence of additional spots on thin-layer plates according to the European Pharmacopoeia. Significant decomposition
was detected as an intense spot in the TLC-test. The spot (r
f
0.7) which had an intensity >5% of the educt spot, depending on the irradiation dose, was eluted and concentrated from preparative
TLC plates. The structure was confirmed by IR and1H or13C-NMR and determined as the cyclic ketale condensation product of acetone and chloramphenicol. Formation of this by-product,
which is acid-catalyzed, was determined as an artifact arising from purity testing. Not the τ-irradiation procedure itself
but traces of acid in combination with acetone as the TLC solvent led to this condensation product which is especially detectable
for small levels of protons (ca. 10−4 mol L−1) stemming from hydrolysis of CAP or decomposition of residual solvents (CHCl3) at low irradiation doses (8 kGy). Substitution of acetone by methanol solvent avoids this and misleading artifact from chromatographic
purity investigations. 相似文献
11.
《Radiation Physics and Chemistry》2006,75(1):87-97
The effect of γ-irradiation on mechanical, thermal, physicochemical and structural properties of polypropylene (PP) syringes was studied. Irradiation doses of 30, 60 and 120 kGy were used with non-irradiated PP syringes serving as control samples. Irradiation caused a significant deterioration in mechanical properties of samples. The compression strength of whole syringe body decreased with increasing irradiation dose. Similarly % extension at break decreased with increasing irradiation dose. Of the physicochemical properties tested, both degree of yellowness and extractable radiolysis products increased with increasing irradiation dose. Melting temperature as well as specific melting enthalpy decreased with increasing irradiation dose. Minor differences in FTIR spectra were observed, mainly in the region of 1720 cm−1, corresponding to the absorption of carbonyl compounds indicating the formation of increased amounts of oxidation products at high irradiation doses. Gas chromatography- mass spectroscopy analysis indicated the formation of a number of radiolysis compounds as a result of irradiation. The number and concentration of these compounds increase progressively with increasing dose until 60 kGy. At the same time a number of compounds initially present in non-irradiated syringes were destroyed by irradiation. 相似文献
12.
Barbara Marciniec M. Kozak Katarzyna Dettlaff 《Journal of Thermal Analysis and Calorimetry》2004,77(1):305-317
Four azole derivatives showing antimycotic activity (Miconazole, Ketoconazole, Clotrimazole, Fluconazole) in solid phase were
exposed to beta irradiation at the dose of 20-200 kGy and then alterations in the physicochemical properties of the above
derivatives were studied using the methods: scanning electron microscopy (SEM), differential scanning calorimetry (DSC) and
X-ray diffraction (XRD) analysis. It was found that the compounds irradiated with sterilising doses (20-50 kGy) showed no
significant alterations in their physicochemical properties, while application of doses >50 kGy resulted in small changes
in the X-ray diffraction patterns and in the course of DSC curves, including a decrease in the melting points and enthalpy
of the process. For Miconazole and Fluconazole, a linear and relatively strong correlation was found (from r =0.9782 to r =0.9003) between the size of the dose of irradiation and the decrease in the melting point and enthalpy value.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
13.
《Radiation Physics and Chemistry》2008,77(9):1039-1045
Volatile and non-volatile radiolysis products and sensory changes of five-layer food packaging films have been determined after gamma irradiation (5–60 kGy). Barrier films were based on polyamide (PA) and low-density polyethylene (LDPE). Each film contained a middle buried layer of recycled LDPE or 100% virgin LDPE (control samples). Data showed that a large number of radiolysis products were produced such as hydrocarbons, alcohols, carbonyl compounds, carboxylic acid. These compounds were detected in the food simulant after contact with all films even at the lower absorbed doses of 5 and 10 kGy. The type and concentration of radiolysis products increased progressively with radiation dose, while no new compounds were detected as a result of the presence of recycled LDPE. In addition, irradiation dose appears to influence the sensory properties of table water in contact with films. 相似文献
14.
Two anticancer drugs, cyclophosphamide (CPH) and doxorubicin hydrochloride (DOXO), in powder form were exposed to a range of doses of 60Co gamma and electron beam radiation to study the effects of ionizing radiation. Pharmacopoeia tests, discolouration, degradation products, effect of irradiation temperature and dose rate were investigated. CPH undergoes less than 2% degradation at 30 kGy. Chromatographic studies revealed formation of several trace level degradation products, discolouration and free radicals in the irradiated CPH. N,N-bis (2-chloroethyl) group in the molecule is particularly sensitive to radiation degradation. Irradiation to 5 kGy at low temperature (77 K) did not result in significant changes. DOXO was observed to be quite radiation resistant and did not undergo significant changes in its physico-chemical properties and degradation product profile. It can be radiation sterilized at normal sterilization dose of 25 kGy. 相似文献
15.
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
16.
Barbara Marciniec Maciej Stawny Karol Olszewski Maciej Kozak Marek Naskrent 《Journal of Thermal Analysis and Calorimetry》2013,111(3):2165-2170
The effect of ionising radiation on the physico-chemical properties of three derivatives of xanthine: caffeine, theophylline and theobromine, has been studied. The above-drugs in the solid phase have been irradiated with E-beam of the energy 9.96 MeV with the doses varied from 25 to 400 kGy. The effects of the irradiation have been examined by differential scanning calorimetry (DSC), electron paramagnetic resonance (EPR) and high-performance liquid chromatography (HPLC). The results have shown that the methylxanthine derivatives studied are resistant to ionising irradiation in the doses usually used for sterilisation (<50 kGy), which means that they are relatively radiochemically stable and can be sterilised by irradiation. 相似文献
17.
Summary The radiolysis products of chloramphenicol under γ-radiation sterilization were investigated systematically. Eight main radiolysis
products were identified and quantified by HPLC-MS and HPLC-DAD, including two compounds never before reported. The minor
radiolysis products were quantified, which shows that they are at concentration levels<threshold for identification. Carbon-carbon
rupture reaction and oxidation reaction are proposed as the main radiolysis reactions of chloramphenicol powder. The applicability
of γ-sterilization for chloramphenicol products was evaluated quantitatively with qualitative and quantitative data that were
compared to the threshold requirements of international regulations for identification. It was concluded that toxicities of
the radiolysis products of chloramphenicol produced by γ-radiation sterilization can be neglected, the radiolysis products
are safe for human health from the chemical view. 相似文献
18.
B. Jaleh P. Parvin N. Sheikh F. Ziaie M. Haghshenas L. Bozorg 《Radiation Physics and Chemistry》2007,76(11-12):1715-1719
In this work, polycarbonate (PC) film samples were irradiated with 10 MeV electrons at different doses ranging from 25 to 250 kGy. Characterization techniques viz. thermogravimetric analysis (TGA), Fourier transform infra-red spectroscopy (FTIR), X-ray diffraction analysis (XRD) and electron paramagnetic resonance (EPR) were exploited to understand the induced changes in the physico-chemical properties of the polymer. An increase in the decomposition temperature with increasing dose was observed, while the crystallinity remained unchanged as a result of the formation of cross-link bond. EPR technique characterized the stability of the free radicals in the irradiated PC. The result showed that cross-linking process occurs at low absorbed doses, whereas polymer degradation happens at higher doses. 相似文献
19.
The accumulation of CO
2
-
radicals in γ-irradiated porcine, chicken, bovine, walleye pollack, and navaga bone tissues and chicken eggshells was studied
by EPR spectroscopy for the purpose of detecting irradiated food and evaluating the dose absorbed during its radiation processing.
It was found that, in the dose range 0–10 kGy, the concentration of radicals is a linear function of dose, and the variation
coefficient of the radiationchemical yield of radicals is no higher than 30% for bone tissues from various biological species.
The applicability of the additive dose method to the EPR dosimetry of irradiated beef was examined. A linear regression model
used in the additive dose method was found to give overestimated results, as compared with an exponential fitting model. 相似文献
20.
A. N. Krasovskii S. V. Borisova N. A. Osmolovskaya I. V. Vasil’eva S. V. Myakin 《High Energy Chemistry》2011,45(4):259-264
The surface properties and the functional-chemical composition of plasticized cellulose triacetate (TAC) films subjected to
electron-beam treatment in the absorbed dose range of D = 25–150 kGy have been studied. It has been shown that a decrease in the contact angle of water on the films at D = 25–75 kGy is caused by an increase in the concentration of carboxyl and hydroxyl groups formed during the radiolysis of
the plasticizer dibutyl phthalate. A high adhesive strength of gelatin emulsion layers obtained on the films irradiated at
D = 50 kGy is due to the formation of chemical bonds between gelatin amino groups and TAC carboxyl groups. 相似文献