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Bakirov A, Kopishev E, Kadyrzhan K, Donbaeva E, Zhaxybayeva A, Duisembiyev M, Suyundikova F, Suleimenov I. The Method of Direct and Reverse Phase Portraits as a Tool for Systematizing the Results of Studies of Phase Transitions in Solutions of Thermosensitive Polymers. Gels 2024; 10:395. [PMID: 38920941 PMCID: PMC11203281 DOI: 10.3390/gels10060395] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2024] [Revised: 05/29/2024] [Accepted: 06/07/2024] [Indexed: 06/27/2024] Open
Abstract
It is shown that a more than significant amount of experimental data obtained in the field of studying systems based on thermosensitive hydrophilic polymers and reflected in the literature over the past decades makes the issue of their systematization and classification relevant. This, in turn, makes relevant the question of choosing the appropriate classification criteria. It is shown that the basic classification feature can be the number of phase transition stages, which can vary from one to four or more depending on the nature of the temperature-sensitive system. In this work, the method of inverse phase portraits is proposed for the first time. It was intended, among other things, to identify the number of phase transition stages. Moreover, the accuracy of this method significantly exceeds the accuracy of the previously used method of direct phase portraits since, for the first time, the operation of numerical differentiation is replaced by the operation of numerical integration. A specific example of the application of the proposed method for the analysis of a previously studied temperature-sensitive system is presented. It is shown that this method also allows for a quantitative comparison between the results obtained by the differential calorimetry method and the turbidimetry method. Issues related to increasing the resolution of the method of direct phase portraits are discussed.
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Affiliation(s)
- Akhat Bakirov
- Department of Chemistry and Technology of Organic Substances, Natural Compounds and Polymers, Faculty of Chemistry and Chemical Technology, Al Farabi Kazakh National University, Almaty 050040, Kazakhstan;
- Department of Telecommunication Engineering, Institute of Communications and Space Engineering, Gumarbek Daukeev Almaty University of Power Engineering and Communications, Almaty 050040, Kazakhstan;
| | - Eldar Kopishev
- Department of Chemistry, Faculty of Natural Sciences, L.N. Gumilyov Eurasian National University, Astana 010000, Kazakhstan; (E.D.); (A.Z.); (M.D.); (F.S.)
| | - Kaisarali Kadyrzhan
- Department of Telecommunication Engineering, Institute of Communications and Space Engineering, Gumarbek Daukeev Almaty University of Power Engineering and Communications, Almaty 050040, Kazakhstan;
| | - Elvira Donbaeva
- Department of Chemistry, Faculty of Natural Sciences, L.N. Gumilyov Eurasian National University, Astana 010000, Kazakhstan; (E.D.); (A.Z.); (M.D.); (F.S.)
| | - Aigerim Zhaxybayeva
- Department of Chemistry, Faculty of Natural Sciences, L.N. Gumilyov Eurasian National University, Astana 010000, Kazakhstan; (E.D.); (A.Z.); (M.D.); (F.S.)
| | - Marat Duisembiyev
- Department of Chemistry, Faculty of Natural Sciences, L.N. Gumilyov Eurasian National University, Astana 010000, Kazakhstan; (E.D.); (A.Z.); (M.D.); (F.S.)
| | - Faiziya Suyundikova
- Department of Chemistry, Faculty of Natural Sciences, L.N. Gumilyov Eurasian National University, Astana 010000, Kazakhstan; (E.D.); (A.Z.); (M.D.); (F.S.)
| | - Ibragim Suleimenov
- National Engineering Academy of the Republic of Kazakhstan, Almaty 050010, Kazakhstan
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Piotrowski M, Maras P, Kozicki M. On the Use of the Fricke-Pluronic F-127 Gel Dosimeter for Radiation Isocenter Testing of a Medical Linear Accelerator. MATERIALS (BASEL, SWITZERLAND) 2024; 17:1521. [PMID: 38612035 PMCID: PMC11012804 DOI: 10.3390/ma17071521] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2024] [Revised: 03/19/2024] [Accepted: 03/25/2024] [Indexed: 04/14/2024]
Abstract
This work presents a Fricke-XO-Pluronic F-127 2D radiochromic dosimeter with a flat-bed scanner for 2D reading and a dedicated data processing software package as a tool for performing coincidence testing of the radiation and mechanical isocenter of a medical accelerator. The optimal irradiation parameters were determined as follows: monitor units per beam and multi-leaf collimator gap, which are ≤750-≤2500 MU and 2-5 mm, respectively, for a cuboidal container with dimensions of 12 × 12 × 0.3 cm3. Despite the diffusion of Fe3+ ions occurring during irradiation, 2D reading can be performed at least 3 h after irradiation, without affecting the calculation performance of the coincidence test. The test was successfully performed for various irradiation settings. Overall, the Fricke-XO-Pluronic F-127 dosimeter has proven to be a potential tool for the coincidence testing of medical accelerators.
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Affiliation(s)
- Michał Piotrowski
- Department of Mechanical Engineering, Informatics and Chemistry of Polymer Materials, Faculty of Materials Technologies and Textile Design, Lodz University of Technology, 90-543 Lodz, Poland;
| | - Piotr Maras
- Department of Radiotherapy Planning, Copernicus Hospital, 93-513 Lodz, Poland;
| | - Marek Kozicki
- Department of Mechanical Engineering, Informatics and Chemistry of Polymer Materials, Faculty of Materials Technologies and Textile Design, Lodz University of Technology, 90-543 Lodz, Poland;
- GeVero Co., 90-980 Lodz, Poland
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Karger CP, Elter A, Dorsch S, Mann P, Pappas E, Oldham M. Validation of complex radiotherapy techniques using polymer gel dosimetry. Phys Med Biol 2024; 69:06TR01. [PMID: 38330494 DOI: 10.1088/1361-6560/ad278f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Accepted: 02/08/2024] [Indexed: 02/10/2024]
Abstract
Modern radiotherapy delivers highly conformal dose distributions to irregularly shaped target volumes while sparing the surrounding normal tissue. Due to the complex planning and delivery techniques, dose verification and validation of the whole treatment workflow by end-to-end tests became much more important and polymer gel dosimeters are one of the few possibilities to capture the delivered dose distribution in 3D. The basic principles and formulations of gel dosimetry and its evaluation methods are described and the available studies validating device-specific geometrical parameters as well as the dose delivery by advanced radiotherapy techniques, such as 3D-CRT/IMRT and stereotactic radiosurgery treatments, the treatment of moving targets, online-adaptive magnetic resonance-guided radiotherapy as well as proton and ion beam treatments, are reviewed. The present status and limitations as well as future challenges of polymer gel dosimetry for the validation of complex radiotherapy techniques are discussed.
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Affiliation(s)
- Christian P Karger
- Department of Medical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, D-69120 Heidelberg, Germany
- National Center for Radiation Research in Oncology (NCRO), Heidelberg Institute for Radiation Oncology (HIRO), Heidelberg, Germany
| | - Alina Elter
- Department of Medical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, D-69120 Heidelberg, Germany
- National Center for Radiation Research in Oncology (NCRO), Heidelberg Institute for Radiation Oncology (HIRO), Heidelberg, Germany
- Department of Radiation Oncology, University Hospital Heidelberg, Im Neuenheimer Feld 400, D-69120 Heidelberg, Germany
| | - Stefan Dorsch
- Department of Medical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, D-69120 Heidelberg, Germany
- National Center for Radiation Research in Oncology (NCRO), Heidelberg Institute for Radiation Oncology (HIRO), Heidelberg, Germany
| | - Philipp Mann
- Department of Medical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, D-69120 Heidelberg, Germany
- National Center for Radiation Research in Oncology (NCRO), Heidelberg Institute for Radiation Oncology (HIRO), Heidelberg, Germany
| | - Evangelos Pappas
- Radiology & Radiotherapy Sector, Department of Biomedical Sciences, University of West Attica, Athens, Greece
| | - Mark Oldham
- Department of Radiation Oncology, Duke University Medical Center, Durham, NC, United States of America
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Rabaeh KA, Al-Zawaydaih HH, Eyadeh MM, Shatnawi MT. High optical stability of reusable radiochromic polyvinyl alcohol-iodine gel dosimeter for radiotherapy. Radiat Phys Chem Oxf Engl 1993 2022. [DOI: 10.1016/j.radphyschem.2022.110338] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Impact of Salt on Thermal Stability and Dose Response of the Fricke-XO-Pluronic F-127 3D Radiotherapy Dosimeter. MATERIALS 2022; 15:ma15155223. [PMID: 35955164 PMCID: PMC9369736 DOI: 10.3390/ma15155223] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/26/2022] [Revised: 07/15/2022] [Accepted: 07/25/2022] [Indexed: 11/30/2022]
Abstract
Fricke-XO-Pluronic F-127 has recently been proposed as a 3D dosimeter for radiotherapy. It contains the typical ingredients of the Fricke ionizing radiation dosimeter, which are embedded in a physical gel of poly(ethylene oxide)-block-poly(propylene oxide)-block-poly(ethylene oxide) (Pluronic F-127). The main reactions upon irradiation are the conversion of Fe+2 to Fe+3 and the formation of a colored complex with XO ([XO-Fe]+3). The study attempts to optimize the dosimeter in terms of its solution-to-gel transition temperature. In order to lower this temperature, the use of NaCl salt has been proposed. The new composition was characterized in order to obtain information on its thermal performance, storage stability, dose response to irradiation with a medical accelerator emitting different types of radiation, and tissue equivalence. The results obtained show an improvement in the sol-gel transition temperature and dose sensitivity compared to the composition without NaCl and broaden the knowledge of the Fricke-XO-Pluronic F-127.
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Features of PABIG nx 3D Polymer Gel as an Ionising Radiation Dosimeter. MATERIALS 2022; 15:ma15072550. [PMID: 35407883 PMCID: PMC8999682 DOI: 10.3390/ma15072550] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Revised: 03/28/2022] [Accepted: 03/29/2022] [Indexed: 01/27/2023]
Abstract
This work presents the features of the PABIGnx 3D polymer gel dosimeter. It consists of two cross-linkers: poly(ethylene glycol) diacrylate (PEGDA), as one biacrylic component, and N,N′-methylenebisacrylamide (MBA), which is another cross-linker often used in 3D dosimeters. Additionally, it contains oxygen scavenges of copper sulfate pentahydrate and ascorbic acid. All ingredients are embedded in a physical gel matrix of gelatine. Upon irradiation, the biacrylic cross-linking agents (PEGDA and MBA) undergo radical polymerisation and cross-linking, which is manifested by the appearance of the opacity of the intensity related to the absorbed dose. PABIGnx was irradiated with an oncological source of ionising radiation, and analysed by using a nuclear magnetic resonance (0.5 T). The following characteristics were obtained: (i) linear and dynamic dose-response of 0.5 to ~18 Gy and 40 Gy, respectively, (ii) dose sensitivity of 0.071 ± 0.001 Gy−1 s−1, (iii) integral 3D dose distribution for at least 24 days after irradiation, (iv) adequate batch-to-batch reproducibility, (v) dose-response independent of irradiation with 6 MV photons, 15 MV photons, 6 MV photons FFF of 0.0168–0.1094 Gy/s dose rates, and (vi) soft tissue equivalence. The study showed that the features of PABIGnx confirm its suitability for use in 3D radiotherapy dosimetry.
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How Xylenol Orange and Ferrous Ammonium Sulphate Influence the Dosimetric Properties of PVA–GTA Fricke Gel Dosimeters: A Spectrophotometric Study. Gels 2022; 8:gels8040204. [PMID: 35448105 PMCID: PMC9025870 DOI: 10.3390/gels8040204] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2022] [Revised: 03/17/2022] [Accepted: 03/19/2022] [Indexed: 11/19/2022] Open
Abstract
The development of Fricke gel (FG) dosimeters based on poly(vinyl alcohol) (PVA) as the gelling agent and glutaraldehyde (GTA) as the cross-linker has enabled significant improvements in the dose response and the stability over time of spatial radiation dose distributions. However, a standard procedure for preparing FG in terms of reagent concentrations is still missing in the literature. This study aims to investigate, by means of spectrophotometric analyses, how the sensitivity to the radiation dose and the range of linearity of the dose–response curve of PVA-GTA-FG dosimeters loaded with xylenol orange sodium salt (XO) are influenced by ferrous ammonium sulphate (FAS) and XO concentrations. Moreover, the effect of different concentrations of such compounds on self-oxidation phenomena in the dosimeters was evaluated. PVA-GTA-FG dosimeters were prepared using XO concentrations in the range 0.04–0.80 mM and FAS in the range 0.05–5.00 mM. The optical absorbance properties and the dose response of FG were investigated in the interval 0.0–42.0 Gy. The results demonstrate that the amount of FAS and XO determines both the sensitivity to the absorbed dose and the interval of linearity of the dose–response curve. The study suggests that the best performances of FG dosimeters for spectrophotometric analyses can be obtained using 1.00–0.40 mM and 0.200–0.166 mM concentrations of FAS and XO, respectively.
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Study of the Optimal Composition and Storage Conditions of the Fricke-XO-Pluronic F-127 Radiochromic Dosimeter. MATERIALS 2022; 15:ma15030984. [PMID: 35160929 PMCID: PMC8838533 DOI: 10.3390/ma15030984] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Revised: 01/21/2022] [Accepted: 01/24/2022] [Indexed: 02/04/2023]
Abstract
This paper presents the results of research on the Fricke–XO–Pluronic F–127 dosimeter. It consists of a Fricke dosimetric solution and xylenol orange (XO), which are embedded in a matrix of poly(ethylene oxide)-block-poly(propylene oxide)-block-poly(ethylene oxide) (Pluronic F–127). Upon irradiation, Fe+2 ions transform into Fe+3, forming a colored complex with XO ([XO-Fe]+3). The color intensity is related to the dose absorbed. The optimal composition, storage conditions, and radiation-induced performance of the Fricke–XO–Pluronic F–127 dosimeter were investigated. The optimal composition was found to be 1 mM FAS, 50 mM sulfuric acid (H2SO4), 0.165 mM XO in 25% Pluronic F–127. The basic features of this dosimeter are discussed, such as dose sensitivity, linear and dynamic dose range, stability before and after irradiation, storage conditions, dose response for irradiation with 6 and 15 MV photons, and batch-to-batch reproducibility. The obtained results showed a certain potential of the Fricke–XO–Pluronic F–127 for radiotherapy dosimetry.
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Mizukami S, Watanabe Y, Mizoguchi T, Gomi T, Hara H, Takei H, Fukunishi N, Ishikawa KL, Fukuda S, Maeyama T. Whole Three-Dimensional Dosimetry of Carbon Ion Beams with an MRI-Based Nanocomposite Fricke Gel Dosimeter Using Rapid T1 Mapping Method. Gels 2021; 7:233. [PMID: 34940293 PMCID: PMC8701283 DOI: 10.3390/gels7040233] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Revised: 11/23/2021] [Accepted: 11/23/2021] [Indexed: 11/17/2022] Open
Abstract
MRI-based gel dosimeters are attractive systems for the evaluation of complex dose distributions in radiotherapy. In particular, the nanocomposite Fricke gel dosimeter is one among a few dosimeters capable of accurately evaluating the dose distribution of heavy ion beams. In contrast, reduction of the scanning time is a challenging issue for the acquisition of three-dimensional volume data. In this study, we investigated a three-dimensional dose distribution measurement method for heavy ion beams using variable flip angle (VFA), which is expected to significantly reduce the MRI scanning time. Our findings clarified that the whole three-dimensional dose distribution could be evaluated within the conventional imaging time (20 min) and quality of one cross-section.
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Affiliation(s)
- Shinya Mizukami
- School of Allied Health Sciences, Kitasato University, Sagamihara 252-0373, Japan; (S.M.); (Y.W.); (T.G.); (H.H.)
| | - Yusuke Watanabe
- School of Allied Health Sciences, Kitasato University, Sagamihara 252-0373, Japan; (S.M.); (Y.W.); (T.G.); (H.H.)
| | - Takahiro Mizoguchi
- Graduate School of Medical Sciences, Kitasato University, Sagamihara 252-0373, Japan;
| | - Tsutomu Gomi
- School of Allied Health Sciences, Kitasato University, Sagamihara 252-0373, Japan; (S.M.); (Y.W.); (T.G.); (H.H.)
| | - Hidetake Hara
- School of Allied Health Sciences, Kitasato University, Sagamihara 252-0373, Japan; (S.M.); (Y.W.); (T.G.); (H.H.)
| | - Hideyuki Takei
- Proton Medical Research Center, University of Tsukuba Hospital, Tsukuba 305-8576, Japan;
| | - Nobuhisa Fukunishi
- Nishina Center for Accelerator-Based Science, RIKEN, Saitama 351-0198, Japan;
| | - Kenichi L. Ishikawa
- Department of Nuclear Engineering and Management, Graduate School of Engineering, The University of Tokyo, Tokyo 113-8656, Japan;
| | - Shigekazu Fukuda
- QST Hospital, National Institutes for Quantum Science and Technology, Chiba 263-8555, Japan;
| | - Takuya Maeyama
- Nishina Center for Accelerator-Based Science, RIKEN, Saitama 351-0198, Japan;
- Department of Chemistry, School of Science, Kitasato University, Sagamihara 252-0373, Japan
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