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In the article titled “Exploitation of solid targetry for Scandium-44 production at INMAS- A potential alternative to generator produced radioisotopes”, published on page S32, Issue Abstract Supplement, Volume 32 of Indian Journal of Nuclear Medicine,[1] the name of the author Aruna Kaushik is missing.

The author names should be correctly read as Shubhra Chaturvedi, Puja Panwar Hazari, Aruna Kaushik and Anil K Mishra*

The term “44 Sc” was incorrectly written as “44 Sc” the term “68 Ga” was incorrectly written as “68 Ga”, the term “44 Ti/44 Sc” was incorrectly written as “44 Ti/44 Sc”, the term “nat CaCO3” was incorrectly written as “nat CaCO3” on page S32, under Objective, Material and Method, Results and Discussions paragraph.

The correct paragraphs should be read as below:

Isotope Production Objective: The aim of this work is to develop an alternative method of production of long lived PET radioisotopes (44-Scandium) in quantities and quality useful for medical purposes in India.44 Sc is useful in PET imaging (T1/2 = 3.97 h; Eβ+ = 1475 keV, 94.3%). The longer half-life permit longer radiolabeling manipulations and transportation to remote areas. It can be a potential alternative to 68 Ga in clinical PET diagnosis, offering longer half-life and better resolution than 68 Ga. Production options for 44 Sc include 44 Ti/44 Sc generator or cyclotron production. At INMAS, the production was planned using 16.5 MeV medium sized medical cyclotron at INMAS. The produced 44 Sc was planned to label the well-characterized DOTA analogues. The tracers will be assessed with respect to their in vivo pharmacokinetic imaging capacity, as well as the total radiation dose to the patients in a head-to-head comparison with 68 Ga -labeled analogues.

Material and Method: The entire production was planned as stepwise optimization with following steps involved: (a) Development of a targetry system (b) Development/optimization of the separation method and (c) Chelator development for scandium. The production of 44 Sc from natural 40-calcium was planned using the 16.5 MeV medium sized medical cyclotron at INMAS. Pellets of target were prepared by pressing method and placed in aluminium target. The target was cooled using water and air combination and irradiated for varying time (5-10 min) and varying beam currents (5-10 μA). The absolute radioactivity of 44 Sc and other obtained radionuclides was measured.

Results and Discussion: A prototype shuttle was designed which could result in a homogenous target and ensure that there will be higher 44 Sc yields. Calculations were carried using the beam energy to arrive at the thickness of the shuttle. By beam optimization experiments, it was inferred that 10μA beam current with an irradiation time of 10min was sufficient to have radioactivity. In order to optimally separate 44 Sc from the irradiated calcium targets, a separation system was designed. Briefly, the irradiated nat CaCO3 target was dissolved in acid solution and passed through a combination of Dowex and DGA column to separate scandium.

The statement under Conclusions paragraph was completely incorrect.

The correct statement should be read as “The present study attempts to establish a feasible method for the production of 44 Sc using a medium sized medical cyclotron and optimize its purification.”

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