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A Perspective on Production and Quality Control of Iodine-123 Radiopharmaceutical for Applications in Nuclear Medicine
Address for correspondence: Mr. Rimmo Loyi Lego, Department of Biomedical Engineering (Schaefer School of Engineering), Rising Sophomore, Stevens Institute of Technology, Hoboken, NJ, USA. E-mail: tasumrocky@gmail.com
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Received: ,
Accepted: ,
This article was originally published by Wolters Kluwer - Medknow and was migrated to Scientific Scholar after the change of Publisher.
Abstract
The present work aims to provide a comprehensive analysis of the production methods for Iodine-123 (123I), with a particular focus on recent advances in nuclear medicine in India and relevant future perspectives. 123I, a radioisotope widely used in nuclear medicine for diagnostic imaging, plays a crucial role in the diagnosis and management of various medical conditions. It examines the historical background of 123I production and their importance in the medical field, emphasizing the recent breakthroughs in the field of nuclear chemistry and radiopharmaceuticals. This work also explores the challenges associated with the production of these isotopes, including their short half-lives and complex production routes. In addition, the report highlights emerging technologies and methodologies that have shown promise for more efficient and cost-effective production of 123I. Finally, the report provides an outlook on the future of radiopharmaceuticals (123I and beyond) production, including the potential impact of new advancements on clinical applications and research endeavors.
Keywords
Diagnostic imaging
iodine-123
nuclear medicine
production methods
radioisotopes
radiopharmaceuticals
single-positron emission tomography
Introduction
Since the accidental discovery of radioactivity by Henri Becquerel and Marie Curie in the year 1896 and 1905, the applications for the use of radiation in the field of medicine have come a long way, in the form of what is today known as, “Nuclear Medicine.” This field was eventually recognized as a medical specialty by the year 1946 after Seidlin reported the successful treatment of a patient with an advanced form of thyroid cancer.[1] Although this was a therapeutic use of radioactive iodine, in recent years, there has been immense progress in the applications of nuclear medicine, for noninvasive diagnostic purposes, in order to identify, characterize, quantify, and test on ontogenetic tumor cells that may be formed in the patient’s body.[2] These noninvasive techniques usually range from nonradioisotope-based diagnostic methods such as Holter Monitoring to Radioisotope-based techniques such as positron emission tomography (PET) and single-positron emission tomography (SPECT). However, the purely functional imaging of PET/SPECT could not sequentially register the anatomical images from the patient, thereby being unable to pin-point the exact location of the formed tumor.[3] The problem was finally solved in the mid-2000s with the emergence of the hybrid PET/computed tomography (CT) systems [Figure 1] which also aided in attenuation correction in PET imaging, by adding counts into areas that are more attenuated due to their being deeper or being surrounded by relatively dense structures and subtracting counts from areas that are attenuated to a lesser extent than all other tissues.[4] Although both PET and SPECT are suitable for imaging purposes, PET is often considered superior to SPECT owing to a greater quantification of regional tissue concentrations of radiolabeled pharmaceuticals. This thereby also enables the physician to easily determine Pharmacokinetics (PK or analyzing how the patient’s body might react for the duration of the exposure) and biodistribution of the radiopharmaceuticals, as well as producing three-dimensional (3D) functional process images of the body.
These radioisotope-based technologies primarily depend usually on short-lived radiopharmaceuticals that are produced in medical cyclotrons, a form of compact particle accelerator, that may range from 3 to 70 MeV.[5] Radiopharmaceuticals or medicinal radiocompounds are a group of radioactive pharmaceutical drugs containing a radionuclide. These compounds tend to have high binding-specificity to target tumor cells, with overexpressed receptors, thereby serving to mark the targets with the radionuclide. In a few cases, however, these radionuclides might not require the need for a radio-labeled compound, if they have the capacity to bind to the target on their own.[6]
In such a procedure (SPECT/PET), a small amount of radiopharmaceutical is administered to the patient, and after it has been fully collected inside the body, radiation in the form of gamma rays would be emitted, which is taken up by radiation camera, most often a gamma-camera. The areas with a greater concentration of the radionuclide are referred to as “hot spots,” while those regions that do not absorb the particular radionuclide will appear lighter on the scan image and thereby are called “cold spots.” Thus, by measuring the behavior of the particular radionuclide within the body, the physician can assess and diagnose a range of possible conditions, such as tumors, infections, hematomas, organ enlargement, or cysts.[7] These types of scans can also be used to assess blood circulation and organ function. In the case of Planar Imaging, the gamma camera remains stationary, thereby producing two-dimensional-images. However, in single-photon emission computed tomography (SPECT), the gamma camera rotates around the patient to produce axial “slices” similar to CT scans. In cases such as PET, which uses two cameras, the SPECT data are used to generate 3D images.
Table 1 is reflective of the radioisotopes produced in India, till date, by the Regional Centre-BRIT group at VECC, Kolkata. This report would therefore provide an analysis of I-123 production methods to understand the current state of I-123 production in Cyclotron 30 and beyond. It will also focus on the progress made by BRIT-VECC in producing Iodine-123 (123I) in India.
| Radioisotopes/radiopharmaceuticals | Applications |
|---|---|
| [18F] FDG t1/2≈1.8 h |
PET imaging - abnormal glucose metabolism to detect malignancy |
| [18F] NaF t1/2≈1.8 h |
PET imaging of bone metastasis and bone scan |
|
201Tl Chloride t1/2≈3.06 days |
SPECT imaging of myocardial perfusion and brain tumor imaging |
|
67Ga Citrate t1/2≈3.26 days |
Soft tissue tumor SPECT-imaging |
|
68Ga t1/2≈68 min (68Ga-PSMA-11, 68Ga-DOTATATE) |
Direct tumor imaging for prostate cancer (68Ga-PSMA-11) and neuroendocrine tumor (68Ga-DOTATATE) |
|
64Cu t1/2≈12.74 h (64CuCl2) |
PET imaging of glioblastoma and prostate cancer and targeted radionuclide therapy |
|
123I t1/2≈13.3 h (Na123I) |
Thyroid imaging (SPECT) |
PET: Positron emission tomography, SPECT: Single positron emission tomography, 123I: Iodine-123, VECC: Variable energy cyclotron centre
Medicinal Need for Iodine 123 for Diagnostic Purposes
Radioisotopes play a crucial role in nuclear medicine, enabling noninvasive imaging techniques that provide valuable insights into physiological processes and the functioning of organs and tissues within the human body.[9] Among the various radioisotopes utilized in nuclear imaging, 123I holds significant importance due to its widespread applications in diagnostic imaging, particularly in the context of thyroid-related disorders. However, despite this India still was using 131I for both diagnostic and therapeutic purposes: theranostic. The main health risks associated with exposure to 131I are primarily attributed to its strong affinity for the thyroid gland. Owing to this, physicians are only supposed to administer lower amounts of 131I, since this radioisotope is known to decay via Beta emission (606 keV; 90%) which might be harmful to surrounding cells.[10]
Recent advancements in nuclear chemistry and radiopharmaceutical research have led to the development of different methods for producing I-123, including metallic-based approaches. One notable example of progress in this domain particularly in India, is the ongoing efforts at BRIT group at VECC, MCF Kolkata, to produce I-123, a radioisotope with immense potential for PET imaging.
The thyroid gland
The thyroid gland, shown in Figure 2, plays a critical role in maintaining the body’s metabolic processes and is primarily responsible for the production of thyroid hormones, including thyroxine (T4). T4 [Figure 3] is an essential hormone that regulates various physiological functions, such as metabolism, energy production, and growth. The proper functioning of the thyroid gland is vital for overall health and well-being.[11]
However, disorders of the thyroid gland, such as hypothyroidism and hyperthyroidism, can lead to imbalances in T4 production, resulting in a range of medical conditions and symptoms.[12] For accurate diagnosis and effective management of thyroid disorders, nuclear imaging techniques that can visualize the thyroid gland’s activity and structure are invaluable.[13]
I-123, a gamma-emitting radioisotope which has been extensively utilized in single-photon emission computed tomography (SPECT) imaging of the thyroid gland, is particularly well-suited for this purpose due to its ideal physical properties, including a suitable half-life of approximately 13 h and a predominant emission of gamma radiation. This allows for efficient imaging with low patient radiation exposure and enables the assessment of thyroid function and structure.[14]
When introduced into the body, I-123 is actively taken up by the thyroid gland, where it is incorporated into the synthesis of thyroid hormones, including T4. For this purpose, various scintillation detectors such as NaI (Tl), BGO, LSO are commonly used in nuclear medicine imaging devices for gamma ray detection. I-123 labeled Sodium Iodide, decays by electron capture emitting gamma rays of energy 156 KeV which will be detected by the scintillation detector in the SPECT imaging device. The scintillation crystals used for this purpose should have good energy resolution, high attenuation coefficient, and short scintillation decay constant (to reduce dead time and random coincidence) making them suitable for identifying specific gamma ray energies associated with I-123. By measuring the gamma ray emissions using scintillation detectors, the imaging system can accurately detect the distribution of I-123 within the patient’s body. This provides valuable information about thyroid function, anatomical information, and other relevant physiological processes.[15]
Production Methods for Iodine-123
Cyclotron-based
Cyclotron-based production is one of the prominent methods used for the production of 123I. Cyclotrons are the particle accelerators capable of accelerating charged particles, such as protons or deuterons, to high energies and colliding them with target materials to induce nuclear reactions. The choice of target material and the specific nuclear reaction used in cyclotron-based production determine the yield and purity of the resulting 123I.[16] The most common nuclear reaction employed for cyclotron-based 123I production is the proton-induced reaction on Xenon-124 (124Xe) via the nuclear reaction:
124Xe (p, 2n) 123I.
The production process starts with the target material, which is typically enriched 124Xe gas. This enriched gas is introduced into a target chamber, where it is bombarded with a high-energy proton beam accelerated by the cyclotron.[17] The collision between the protons and the 124Xe nuclei induces a nuclear reaction, leading to the formation of 123I and two neutrons, as shown in the reaction [Figures 4,5].
One of the key advantages of cyclotron-based production is the ability to obtain 123I with high specific activity. Specific activity refers to the radioactivity of a given quantity of a radioisotope, often expressed in curies per milligram or megabecquerels per milligram. High-specific activity is desirable in nuclear medicine applications as it allows for efficient imaging with low injected doses, minimizing patient radiation exposure while maintaining image quality.[18]
One study, by Legoux et al., was successful in producing 123I in a solution of high radioactivity and chemical purity, via 123Xe by irradiation of a sodium iodide (Stable Na127I) target with 108 MeV deuterons using a synchrocyclotron/high-energy cyclotron [Figure 6].[19] However, cyclotron-based 123I production also presents some challenges. One significant obstacle is the limited availability of enriched 124Xe gas, which can be expensive and challenging to procure. In addition, it is also not always feasible or economically viable to use high-energy cyclotrons. A study conducted by Firouzbakht et al. also demonstrated that the amount of 123Xe produced after decay of 123Cs, as shown in Figure 4, is retained in the irradiation cell, possibly because of the diffusion of 123Cs into the metal lattice of the foils of the target medium where it later decays to 123Xe. Thus this is not available for removal during subsequent expansion out of the vessel.[20] In addition, the cross-section (probability of reaction occurrence) for the (p, 2n) reaction is relatively small, resulting in a lower production yield compared to other methods.[21]
To address these challenges and improve the efficiency of cyclotron-based 123I production, researchers have explored alternative target materials and optimized irradiation parameters. For example, the use of enriched Tellurium-124 (124Te) targets has been investigated as an alternative to 124Xe.[21] This methodology of producing 123I from enriched 124Te provides a more convenient and cost-effective option compared to the expensive enriched 124Xe gas target system commonly used for routine 123I production. In addition, the use of 124Te as a target material allows for easier handling and transportation, as it is a solid compared to 124Xe, which is a gas.[22] This eliminates the need for specialized storage and containment measures, reducing the overall complexity and cost of the production process.[23] Moreover, 124Te can be readily obtained in large quantities, making it a more accessible material for 123I production. In contrast, obtaining and maintaining a sufficient supply of enriched xenon gas can be challenging and expensive.[17] However, although the use of tellurium as a target material may result in higher yields of 123I compared to xenon, owing to a higher cross-section of the production reaction with tellurium, using 124Xe still is the only process that is capable of producing 123I with the highest radionuclide purity, as the method using 124Te also leads to the production of unwanted radioiodine isotopes, such as Iodine-124[21] To address this issue, a 1981 study by Barrall et al., demonstrated the potential for producing high purity 123I through a combination of reduced energy and increased isotopic enrichments. The use of a high-power internal target allowed to produce large quantities of 123I in a short period of time, reducing the buildup of longer-lived radio impurities.[24] However, to this date, an adequate supply of isotopically enriched 123Te is not economically viable.
Furthermore, advancements in cyclotron technology have led to the development of compact and versatile cyclotrons, making 123I production more accessible to smaller medical facilities and research institutions. These modern cyclotrons offer increased beam intensity and energy, allowing for higher production rates and improved cost-effectiveness. With ongoing research to optimize target materials, irradiation parameters, and cyclotron technology, the future prospects for cyclotron-based 123I production are promising. Continued advancements in this field are expected to enhance the availability and accessibility of 123I for various diagnostic imaging procedures, further contributing to the progress of nuclear medicine and patient care.[25]
Reactor-based production
Reactor-based production of 123I involves the irradiation of an enriched target material, usually 124Xe target with neutrons (neutron flux) in a nuclear reactor. Neutron activation of 124Xe results in the formation of 123Xe through the (n, 2n) reaction:
124Xe (n, 2n) 123Xe
123Xe, which has a half-life of about 2 h, subsequently decays to produce 123I via the (n, γ) reaction. In this production, the sole radioisotope of Xenon, that can contribute an impurity, is 125Xe, which is produced through an (n, 2n) reaction with 126Xe, and a thermal neutron capture mechanism in 124Xe. This often would also result in the formation of 125I. However, despite this, the γ ray emissions of this Iodine isotope, is comparable to that of 123I and thus, does not alter or affect the SPECT-imaging of 123I. In addition, during the wait time, about 4 h, for 123Xe to decay to 123I, the activity of 125I would be negligible.[26]
One of the key advantages of reactor-based production is the relatively high activity of 123I. Based on previous studies, these would yield around 60 mCi of 123I each day, at an amount that is comparable to that produced in low-energy cyclotrons. However, to produce a high yield, the reaction should occur at a high-flux reactor, which are generally not available. Additionally, the cost of a highly enriched 124Xe is extremely high and there is the added concern of possible leakage. Reactor-based production also often requires a large amount of hot cell time per millicuries produced, when compared to the cyclotron-based production route.[26]
It is also important to note that reactor-based production of 123I generally requires collaboration with nuclear reactor facilities, which may not be available in every region. The logistics of transport and handling of the irradiated target material also pose the challenges.
Recent Advancements and Production in India
Production
The production of 123I at RC-BRIT, VECC, Kolkata, marks a critical advancement in India’s nuclear medicine capabilities. Utilizing a cyclotron, the process begins with electroplating tellurium oxide onto a nickel-coated copper plate as the target material. Through the (p, 2n) reaction on 124Te induced by high-energy proton irradiation, 123I is generated. Following irradiation, the target undergoes radiochemical separation and purification to isolate 123I, which is then converted into sodium iodide for medical applications. This development bolsters India’s radiopharmaceutical production and contributes to global nuclear medicine research.[26]
Quality control
As per European and US Pharmacopoeia, all injections must be sterile, free from any contaminants, and have the appropriate pH, ionic strength, and osmolality. Additionally, radioactive injections must also meet specific criteria for radiochemical and radionuclidic purity.[27] Therefore, quality control of radiopharmaceuticals is extremely important and is carried out in two different aspects: physicochemical and biological quality control.
Physicochemical quality control
Physicochemical quality control plays a crucial role in assessing the reliability and safety of radiopharmaceuticals. Various parameters are evaluated to ensure the physical, radionuclidic, radiochemical, and chemical purity of these compounds.[28]
Physical inspection involves careful examination of the sample’s color, appearance, and pH. This visual assessment helps identify any visible abnormalities or inconsistencies that may affect the overall quality of the radiopharmaceutical.
Radionuclidic purity is an essential aspect of quality control, as it determines the fraction of desired radionuclides present in the sample. Undesired radionuclides may arise from undesired nuclear reactions during target irradiation or the presence of isotopic impurities in the target material. γ-spectroscopy, using a p-type co-axial High Purity Germanium detector connected to a 4k channel MCA system, enables the determination of radionuclidic purity.[29] The γ-ray spectra obtained are compared to a reference source, typically 152Eu, for energy and efficiency calibration.
Radiochemical purity assesses the fraction of total radioactivity present in the desired chemical form of the radiopharmaceutical. Impurities in radiochemical form can result from various factors such as solvent decomposition, presence of oxidizing or reducing agents, incomplete reaction, changes in temperature or pH, and radiolysis. Radiochemical purity can be determined through methods like thin layer chromatography (TLC) or high-performance liquid chromatography. TLC is commonly employed for evaluating the radiochemical purity of compounds labeled with 123I[303132] In this technique, a small sample amount is spotted onto an absorbent material, such as silica gel or cellulose, and subjected to chromatographic separation. By comparing the migration of the labeled compound with reference standards, any unwanted impurities or unlabeled species can be detected and the quality of the labeled compound assured.[3233]
Chemical purity, on the other hand, refers to the fraction of the desired chemical form present in the radiopharmaceutical. Chemical impurities can originate from residual solvents, additives like alkalis, acids or buffers, or breakdown of the material before or after labeling.[34] Partially reacted chemical species during the preparation of the compound can also affect chemical purity.
Biological quality control
The biological quality control of sample solutions involves several tests to assess their safety and effectiveness. One such test is the bacterial endotoxin test (BET), which is estimated using the Limulus amebocyte lysate test.[34] This test can be performed using either the Portable Endotoxin Testing System (PTS) or the Gel Clot technique. The Endosafe® nexgen-PTS™ is a handheld spectrophotometer that is widely used for real-time endotoxin testing, glucan concentration determination, and Gram identification. Before a drug product is released, a 20-min PTS BET must be conducted in-process, followed by a standard 60-min Gel Clot BET after product release.[35]
In the case of radiopharmaceuticals intended for human administration, it is necessary to conduct an apyrogenicity test to ensure the absence of pyrogen. Pyrogens are the substances such as polysaccharides or proteins that are produced by microorganisms and can cause fever and other adverse reactions in the body. It is important to note that while the sterility of a solution does not guarantee its apyrogenicity, the sterilization process cannot effectively eliminate pyrogens in radiopharmaceuticals.[36]
Sterility testing is another vital component of biological quality control. This test aims to detect the presence of bacteria and other microorganisms that may have originated during the preparation of the radiopharmaceutical. After the product is released, postrelease sterility testing must be conducted for each batch.[37] The test involves inoculating the sample into suitable growth media, such as fluid thioglycollate medium (FTM) for anaerobic bacteria and soybean casein digest medium (SCD) for aerobic bacteria. The samples are then incubated at appropriate temperatures for 14 days to allow the growth of any potential contaminants. If no turbidity is observed in both FTM and SCD, it indicates that the product has passed the sterility test.[38]
Challenges in Production and Isotope Availability
The production of 123I presents several challenges related to the availability of suitable target materials, production methods, and yield optimization. One of the main obstacles is the limited availability of enriched 124Xe gas or other stable isotopes required for cyclotron-based production. The procurement of these enriched isotopes can be expensive and complex, hindering large-scale production. Similarly, the availability of nuclear reactors for reactor-based production is not widespread, further impacting the accessibility of 123I. Additionally, the optimization of production methods to achieve higher yields and specific activity remains an ongoing challenge in the field of 123I production.[39]
Current research and preclinical imaging
Recent advancements in the production of 123I have sparked significant interest in preclinical imaging and research applications. Preclinical studies have become instrumental in investigating new radiopharmaceuticals, targeting agents, and imaging modalities. Researchers are exploring innovative methods to optimize target design, cyclotron parameters, and irradiation conditions for improved 123I production efficiency. Moreover, preclinical imaging studies using 123I are contributing to the development of novel radiotracers and therapeutic agents, thereby expanding the potential applications of 123I beyond traditional nuclear medicine.[30]
Short half-life and shelf-life limitations
The short half-life of 123I, approximately 13 h, poses challenges in its distribution and use in clinical settings. This limited half-life restricts the time available for transportation from the production site to medical facilities, potentially leading to a reduced supply of fresh 123I. The shelf life of 123I is further constrained due to its decay, making it imperative for healthcare providers to manage and utilize the radioisotope efficiently.[40] These limitations necessitate close coordination between production centers, radio pharmacies, and medical facilities to ensure timely delivery and utilization of 123I for diagnostic imaging and therapeutic applications.[41]
Supply chains and infrastructure challenges
Establishing robust and reliable supply chains for 123I distribution is critical for its widespread availability in medical facilities. The transportation of the short-lived 123I radioisotope demands efficient logistics and storage facilities to maintain its radiochemical integrity and quality during transit. The challenge is amplified in regions with limited nuclear medicine infrastructure, where the establishment of specialized radio pharmacies and handling facilities becomes necessary.[30] Ensuring a continuous supply of 123I requires a well-coordinated network between production centers, radio pharmacies, and healthcare providers, emphasizing the need for collaboration and investment in nuclear medicine infrastructure.
Emerging Technologies, Methodologies, and Future Prospects
Alternative target materials and production routes
Advancements in nuclear chemistry have spurred the exploration of alternative target materials and production routes for 123I to overcome the existing challenges and enhance production efficiency. One promising avenue is the investigation of using 124Xe as a target material instead of Tellurium. Xenon-based production routes, such as the (p, 2n) reaction on 124 Xe, offer higher cross-sections and potentially improved 123I production yields.[42] Additionally, researchers are exploring other alternative production routes, including alternative particle accelerators, such as laser-driven accelerators, which may provide new opportunities for cost-effective and compact 123I production.[43] Linear accelerators, have also shown promise in the past, as unlike cyclotrons they also can accelerate the near massless electron.[44]
Automation and process optimization
Automation and process optimization are pivotal in improving the overall efficiency and reproducibility of 123I production. Implementing automated systems in target preparation, irradiation, and postprocessing can reduce human error and increase production throughput.[45] Process optimization, including irradiation parameters, reaction kinetics, and purification techniques, can enhance production yields and specific activity. There have been efforts on this front, by a team of Brazilian researchers at IPEN/CNEN-SP, who are working on developing a new system that eliminates the need for human interference in radioisotope production, reducing the potential for failures or incidents. This new system has the capacity to yield 2.70 mCi/mAh per irradiation, which falls slightly below the targeted goal set by the previous 2021 study, by IPEN-CNEN, of 3.5 mCi/mAh. Despite this, it still fulfills a significant portion of the country’s radioisotope demand.[46]
Automation and optimization not only contribute to a more reliable supply of I-123 but also have the potential to streamline production, making it more accessible to a wider range of nuclear medicine facilities.
Prospects for clinical diagnostics and potential impact on the field of nuclear medicine
123I plays a vital role in various clinical diagnostic applications in nuclear medicine. Its usage in single-photon emission computed tomography (SPECT) imaging allows for accurate assessment of thyroid function and structure. In addition, 123I-labeled compounds enable imaging of specific neuroreceptor systems in the brain, aiding in the diagnosis and management of neurological disorders.[47] With ongoing advancements in production methods and the development of novel radiopharmaceuticals, 123I is expected to play an increasingly crucial role in diagnosing a broader range of medical conditions and optimizing patient care.
Conclusion
123I holds a critical position in nuclear medicine, playing a pivotal role in diagnostic imaging and research applications. Moreover, the potential use of I-123 in safe diagnostic imaging offers a personalized and precise approach to patient treatment.
The production of 123I has witnessed significant advancements, with various methods such as cyclotron-based, reactor-based, and isotope generators contributing to its availability. Research efforts have focused on optimizing target materials, irradiation parameters, and purification techniques, resulting in improved production efficiency and specific activity.
However, several challenges remain in 123I production and utilization. Limited availability of enriched target materials, short half-life and shelf life limitations, and infrastructural constraints pose hurdles in ensuring a steady supply of 123I. Addressing these challenges demands continued research, investment in nuclear medicine infrastructure, and robust supply chain management.
Promising prospects lie ahead for 123I in nuclear medicine. Preclinical imaging and research studies are paving the way for the development of novel radiotracers and targeted therapies. As emerging technologies and automation continue to enhance production processes, the accessibility and cost-effectiveness of 123I will improve, benefiting patients and researchers alike.
Despite significant progress, there are certain gaps in the literature that warrant attention. Comprehensive comparative studies evaluating different production methods and target materials are essential to identify the most efficient and viable approaches. Clinical outcome studies, particularly examining the impact of 123I imaging on patient management, are crucial for establishing its clinical utility in various medical conditions. Furthermore, long-term stability studies of 123I-labeled compounds are essential to ensure product quality and safety.
To capitalize on the potential of 123I and nuclear medicine in India, research collaboration, investment in infrastructure, and clinical trials are pivotal. India’s successful production of 123I at MCF, RC-BRIT VECC, Kolkata showcases the nation’s capabilities in nuclear science. Building on this foundation, collaboration with the international nuclear medicine community will facilitate knowledge exchange and promote advancements in 123I production and utilization.
As nuclear medicine continues to evolve, 123I will remain a fundamental radioisotope, influencing research and clinical practices, and contributing to the expansion of nuclear medicine’s role in modern healthcare. By addressing the existing challenges, identifying knowledge gaps, and fostering research collaboration, India can bolster its nuclear medicine capabilities, ensuring the continued growth and impact of 123I in healthcare and scientific endeavors.
Conflicts of interest
There are no conflicts of interest.
Acknowledgment
I am immensely indebted to my advisor and mentor Dr. Sankha Chattopadhyay, Officer-in-charge, RC-BRIT, Kolkata, India, who provided invaluable insights and guidance throughout the completion of this review. I would also like to thank Ms. Shayantani Ash and Mr. Samarjit Singha (RC-BRIT, Kolkata) for their time, patience, and dedication in teaching me and providing guidance throughout this endeavor. Further I would like to thank Mr. Md. Nayer Alam and Smt. Madhusmita for their continued support, guidance and encouragement throughout the process. I would also like to thank Mr. D. G. Mahesh, for his invaluable insights into the applications of nuclear medicine, and for introducing me to the interdisciplinary nature of the field and engineering. Special thanks to Dr. Nabhiraj P.Y., training coordinator at VECC Kolkata, for providing me with this opportunity to work on a month-long project in the field of Diagnostics and Nuclear Medicine as well as for his support. I would also like to thank Ms Ranji, for her continued support. Additionally, I would also like to acknowledge Director VECC, Dr. Sumit Som, for his support. Also, sincere thanks to everyone at the Medical Cyclotron Facility and VECC Kolkata for their continued support and assistance throughout this research.
I am also indebted to my Chemistry Professor and Pre-Medical Advisor, Dr. Muisener and my Academic Advisor Mrs. Amy Mattare, for always inspiring and encouraging me. Lastly, immense thanks to my High School Chemistry Teacher, Deepti Ma’am for imbibing in me a love for the natural sciences, and always motivating me to think beyond the confines of the textbook.
Nil.
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