Correlation between iodide dosimetry and terephthalic acid dosimetry to evaluate the reactive radical production due to the acoustic cavitation activity

Ebrahiminia, Ali; Mokhtari‐Dizaji, Manijhe; Toliyat, Tayebeh

doi:10.1016/j.ultsonch.2012.05.016

Cited by 43 publications

(23 citation statements)

References 28 publications

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“…5b. This is different from the studies of Ebrahiminia et al and Barati et al, who showed that continuous ultrasound also induced higher cavitation activities than 20% DC with a compensated duration [27,31]. One explanation is that the sonication durations in our study were relatively short (1-10 min), whereas, in the studies of Ebrahiminia et al and Barati et al, the durations were in the range of 20-100 min.…”

Section: Discussioncontrasting

confidence: 99%

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The decomposition of protoporphyrin IX by ultrasound is dependent on the generation of hydroxyl radicals

Sun

Yao

et al. 2015

Ultrasonics Sonochemistry

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The ultrasound activation of certain drugs, such as porphyrins, could cause synergistic cytotoxic effects on cells. Both sonomechanical and sonochemical effects occur and the latter play a critical role because antioxidant agents could exert significant protective effects against the cytotoxicity. To investigate the reactive oxygen species involved in the sonochemical effects, aqueous protoporphyrin IX (PpIX) solutions were characterized under ultrasound sonication in this study. Inertial cavitation was indirectly evaluated using terephthalic acid dosimetry. The fluorescence intensity of the PpIX was measured using a fluorescence spectrophotometer. The effects of PpIX concentration, ultrasound parameters and free radical scavengers on the PpIX activation by ultrasound were investigated. Our results showed that the increase in PpIX decomposition was significantly correlated with cavitation activities (R=0.9874, p<0.05), and the decomposing effect increases with ultrasound intensity (0.6-1.5 W/cm(2)), initial PpIX concentration (1-5 μM), duty cycle (10-100%) and the sonication duration (2-10 min). The fluorescence and absorption spectra of PpIX showed a decrease in the peak intensity without spectral shifts or new peak build-up after sonication. The PpIX decomposition was significantly inhibited by hydroxyl radical scavengers, histidine, mannitol, acetone, methanol and ethanol, but the decomposition was not inhibited by sodium azide, catalase or superoxide dismutase. These results suggest that the decomposition of protoporphyrin IX by ultrasound is dependent on the generation of hydroxyl radicals, which sheds some light on the sonochemical effects of the interaction between ultrasound and porphyrins.

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Section: Discussioncontrasting

confidence: 99%

“…Ebrahiminia et al used iodide dosimetry to evaluate the inertial cavitation activity and showed that continuous ultrasound produced more sonochemical effects than burst ultrasound [31]. Our results also showed that with the same sonication duration, continuous ultrasound induced more PpIX decomposition than burst ultrasound (Fig.…”

Section: Discussionsupporting

confidence: 71%

The decomposition of protoporphyrin IX by ultrasound is dependent on the generation of hydroxyl radicals

Sun

Yao

et al. 2015

Ultrasonics Sonochemistry

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“…Lida et al (2005) showed that the degree of gas saturation, the type of gas, and the temperature of a sonicated dosimeter solution at different sonication frequencies play an important role in determining the extent of inertial cavitation occurrence. Further, Ebrahiminia et al (2013) observed that sonication frequency plays an important role for reactive radical generation in the medium and showed that with increasing the sonication frequency, the cavitation yield increased when the frequency was greater than 250 kHz.…”

Section: Effect Of Sonication Frequencymentioning

confidence: 99%

“…They observed that the concentration of KI and temperature affect the cavitation yield of the system such that the iodine production is proportional to both conditions. Furthermore, Ebrahiminia et al (2013) studied the efficacy of different exposure parameters on cavitation production by 1 MHz ultrasound using iodide dosimetry and reported that with increasing time of sonication or intensity, the absorbance is increased.…”

Section: Introductionmentioning

confidence: 99%

Towards the development of cavitation technology for upgrading bitumen: Viscosity change and chemical cavitation yield measurements

Kirpalani

Mohapatra

2017

Pet. Sci.

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Among the different methods used for reducing viscosity of bitumen, acoustic cavitation during sonication is well recognised. Several chemical methods were used to detect the production of reactive species such as hydroxyl radicals and hydrogen peroxide during acoustic cavitation processes. However, quantification of cavitation yield in sonochemical systems is generally limited to low frequencies and has not been applied to bitumen processing. An empirical determination of the cavitation yield in midto high-frequency range (378, 574, 850, 992, and 1173 kHz) was carried out by measuring the amount of iodine liberated from the oxidation of potassium iodide (KI). Further, cavitation yield and the effects of different sonic operating conditions such as power input (16.67%-83.33%) and solute concentration on cavitation yield were carried out in KI solution and sodium carboxymethyl cellulose-water mixture to obtain benchmark changes in rheology and chemistry using these two model fluids. The findings were then applied to bitumen upgrading through sonication. Through this study, it was found that the chemical cavitation yield peaked with a sonication frequency of 574 kHz. It was also found that cavitation yield and viscosity change were correlated directly in bitumen and a 38% lower bitumen viscosity could be obtained by acoustic cavitation.

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“…Microbubbles grow and collapse when irradiated with US (8,9), and during sonoporation, H 2 O 2 is produced in the medium (10). This free radical production can be measured using the starch-iodide method (11), by which free radicals are quantified when combined with potassium iodide (KI) (12).…”

Section: Introductionmentioning

confidence: 99%

Introduction of plasmids into gastric cancer cells by endoscopic ultrasound

et al. 2017

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Abstract. Short hairpin RNA of frizzled-2 (shRNA-Fz2) suppresses the cell proliferation of gastric cancer cells. Endoscopic ultrasound (EUS) is considered a suitable method for the introduction of therapeutic plasmids into cells, since the device enables the access and real-time monitoring of gastric cancer tissues. In the present study, plasmids were introduced into cells by sonoporation, as evidenced by the production of H 2 O 2 . The production of H 2 O 2 was measured by absorbance of a potassium-starch solution irradiated with EUS. Luciferase activity was analyzed in the cells irradiated with EUS after the addition of a pMetLuc2-control in the media, and cell proliferation was analyzed using a 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium inner salt assay after irradiation with EUS following the addition of shRNA-Fz2. Absorbance levels corresponding to free radical levels were found to be higher in the cells irradiated with EUS. Luciferase activities were found to be significantly higher in the transfected cells (plasmid with Lipofectamine LTX) than in untreated cells and were furthermore found to be higher in MKN45 cells irradiated for 0.5 min than in cells not subjected to irradiation. Luciferase activity was also found to be higher in MKN74 cells irradiated for 2 min than in cells that were not irradiated. Although the cell proliferation of the MKN45 cells tended to be suppressed by irradiation with EUS, this was non-significant suppression, while the cell proliferation of MKN74 cells was found to be suppressed by irradiation with 12 MHz for 2 min (P<0.05). In conclusion, plasmids were introduced into cultured gastric cancer cells by irradiation with EUS due to sonoporation, as evidenced by the production of H 2 O 2 ; however, the efficiency of the plasmid introduction was low compared with a traditional transfection approach.

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Correlation between iodide dosimetry and terephthalic acid dosimetry to evaluate the reactive radical production due to the acoustic cavitation activity

Cited by 43 publications

References 28 publications

The decomposition of protoporphyrin IX by ultrasound is dependent on the generation of hydroxyl radicals

The decomposition of protoporphyrin IX by ultrasound is dependent on the generation of hydroxyl radicals

Towards the development of cavitation technology for upgrading bitumen: Viscosity change and chemical cavitation yield measurements

Introduction of plasmids into gastric cancer cells by endoscopic ultrasound

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