 Hello everyone. In the previous lecture, I discussed about the production of radioisotopes by radiating the target's neutrons and also we discussed how we can produce the carrier-free radioisotopes by different means. In this particular part, I will discuss the radioisotope production using charge particles and also some of the other aspects of radioisotope production like what are the ways how the radioisotopes are handled after radiation and in particularly in the Indian context, what are the mechanisms and processes by which the isotopes are produced and supplied to the regions. So, in the charge particle radiation, you can use a cyclotron or a linear accelerator or a tandem accelerator. Tandem means two-stage accelerator and then depending upon the radiation time, the facility that is available to you, you can get the radioisotopes, you need the suitable beam and the target. So, the knowledge of nuclear reaction will be very much useful in choosing what beam, what target. So, before you have a cyclotron and it is giving proton beam, then you already have the projectile fixed. So, now, you can fix the target accordingly go for the isotope production. Before you go for the radioisotope production, you need to know the excitation function. That means the cross section. So, this is the cross section sigma r versus energy of the projectile. Then this is the total cross section and you will have the excitation functions of different products like alpha n, alpha 2n, alpha 3n and so on. So, depending upon the excitation function for a particular radioisotopes, you have to choose the energy of the projectile and also make sure that it is available from the machine that you have to use. So, these aspects we have already discussed in the previous lectures on nuclear reaction. Now, we come to see what are the isotopes that can be produced using proton, uterine and this alpha particles. The heavy ions at projectiles can be used for the rest of production, but you will find that the heavy ions are having multiple charges. So, the currents are low and you may produce many other isotopes which may not be useful. So, mostly for commercial applications or applications in the industry or healthcare, whatever radioisotopes are produced, they are either produced using protons or alpha particles, uterium using cyclotrons because cyclotrons produce give rise to very high beam intensities. Beam intensity means current in microamperes. So, 1 microamperes of proton will have 6.24 10 power 12 particles per second. Accordingly, 1 microamperes of 1 microamperes or alpha particles of 1 microamperes current it will have is a 2 plus charge state 6.24 upon 2. That is how typical currents, some of the accelerators produce milliamp currents. Like for medical cyclotrons, you want very high activity of a short lived isotope to go for milliamp current. 1 milliamp 10 power 15 alpha particles of protons per second. That is the kind of intensities you use. So, proton induced reactions are used to produce fluorine 18. You can produce cadmium indium 111 and F18 is a used in pet, the positron emission tomography. So, you this F18 is having only 109 minutes supply. So, about 2 hours and so you irradiate H2O18, H2O18 and PN2 H18F and you have to do very quick chemistry because the half line is only 109 minutes. And you tag a glucose molecule, fluorodeoxyglucose and the tag is F18. So, and then you can transport it to hospital for pet operations. This 111 also used in the analysis, the diagnosis of diseases, 111 indium indium is beautiful gamma lines 100 to 200 kV range. So, it is also used in plastics. Again, another isotopes gallium 69 PN reaction P200, germanium 68. The germanium 68 has a half life of 270 days which decays to gallium 68 which is a beta plus emitter and hence it is a pet radioisopropyl. Any beta plus emitter being short lived are ideal for pet radioisopropyl, pet diagnosis, positron emission tomography. So, you can have a generator system, germanium, gallium generator system. So, because you have to supply this gallium 68 to the hospitals. So, in the hospital you can have a germanium 68 column and don't milking every few hours gallium 63. Similarly, thalium 201, thalium 201 is used in stress test single photon emission computer tomography. Irradiate thalium 201, this is actually thalium 203, 201, P3N led 201 and which is emitting the plus or electron capture give rise to thalium 201. And this has been half life of few days in 10 minutes for stress analysis, camera, scintigraphy camera. 125th iodine 60 days is another isotope iodine used in, it means a low energy gamma ray and it is used in a radio in say of iodine like thyroid hormones. So, iodine 127 P3N, dienone 125 and 127 iodine, you can also produce by 127 iodine target P5N, dienone 153 goes to 123 iodine. So, some of the isotopes of iodine 123, 125 apart from 131, 131 is a beta emitter and these are emitting electron capture and the acceleration low energy gamma. So, depending upon the type of application you have, you can choose which isotope of iodine suitable. Viterium targets are used to produce sodium 22 and oxygen 15, sodium 22 is a positon emitter though it is not huge impact because it has got a half life of about a year or two. So, but it is a source for calibration. So, it emits high level KV gamma rays. So, if you want to calibrate your system and you can filter the chemistry of positonium. So, positon is a positon source and many chemistry of positonium atoms are done with sodium 20. In fact, there are positon beams, you can take a source of sodium 22 which is emitting positon and you can accelerate these positons to use for many reasons. Oxon 15 is a beta emitter and you can use this by for the PET analysis, a short lived isotope produced by 1914 Dn reaction. For alpha induced reaction again 111 indium, emission 95, plutonium 238, plutonium in the heat source or the space applications in satellites, you can use some power. See, typically 1 watt or if you want to have 1 watt in heat, then about 2 grams or 1 gram of plutonium 238 gives some 2 watts. So, typically that is the kind of wattage you can get from plutonium in the heat source. So, these are the isotopes that are produced in e-luene excitons. There will be many and just giving you examples, there are more isotopes. In fact, we will come along, we will discuss further. So, many radioisotopes which are not produced in radioisotopes and many reactors and many isotopes which have different types of applications where you require carrier free, it may not be possible by reactor. So, you go for accident. So, this is the list of cyclotone produced radioisotopes, sodium 22, magnesium 24, the alpha over 57, little 58, P2N, gallium 68. You can directly produce gallium 68 or you can go for gallium 69, P2N reaction, indium 111, cadmium 112, P2N, iron 130, 123, tellurium or genome as a target material, helium 201, helium 203, P3N, lead 201, followed by pressure decay. Carbon 11, nitrogen 13 and oxal 50, these are all positon emitters. Short-lived ones you can see, 20 minutes, 9 minutes and 122 seconds and 109 minutes, they are all positon emitters. Some of these isotopes are actually, the cyclotones coupled with the pet facility directly with half-lives are very short. So, these are the reactions used for producing these alpha positon emitters and they are widely used in pet telephones. Caladium 103, 16 days, again rhodium 103, P2N reaction. So, you will find there are hundreds of radioisotopes having different applications. So, what we can do, you can just suppose you want pressure of a particular element, want to trace the path of an element, take the nuclear chart, look for the isotope having suitable half-life decay characteristics and then see in what way you can produce a particular radioisotope. So, having the knowledge of nuclear reactions, you should be in a position to find out a reaction which will give you the desired isotope, proper yield, particular activity and whatever activity you need and particular chemical form also should be the chemistry and delivery to the futures. So, let us compare the radioisotope production in a reactor and the cyclotone with different attributes. You can see here in the case of a reactor, reactor is in a big sea of neutrons. So, you can irradiate large amount of target material like oval metal, you can irradiate 10-20 grams, 100 grams. But in a cyclotone where the beam is travelling, beam, first of all the beam dimensions are very small, few millimeters. So, you cannot irradiate large quantity, even if you irradiate larger pile, it will not bombard that material, only a very small section, first section the target will be irradiated. So, small amount of target only can be irradiated in the cyclotone. So, cyclotone I am saying is the representative of an accelerator, but most of the time you will find the isotope production by chart particles is mostly done in cyclotones. So, I am just comparing reactor and cyclotone, but this is also valid for any chart particle accelerator. Accordingly the specific activity is generally low in reactor neutron irradiation, particularly you know when the target material is irradiated and become by N gamma reaction you get the isotope of the same element. There have been cases like multiple neutron capture or model this one beta decay, N gamma problem beta minus decay, then you can get carrier free, but in general if you irradiate a target material by N gamma you will get low specific activity. In cyclotone you are using a chart particle, so you are changing the atomic number of the isotope compared to target. Therefore, you have very high specific activity for the neutron isotopes. Number of targets at a time in a reactor you can irradiate large number of radioactors in the target materials. So, at a time many targets are being irradiated and you can just remove which one you want to remove depending upon the time of irradiation and their half-life. So, you can irradiate many targets in the reactor. So, throughput is very high, but in a cyclotone at a time only one target. We suppose you have multiple beam lines, at a time the beam will go in a particular beam line. So, there is no point putting irradiation in other beam lines at that point of time. At a time only one target irradiation. Irradiation time can be kept long like I was telling Kovalt you know if you irradiate for years to do apply this 5.27 years, so you can irradiate for one year. In the case of accelerators you cannot create irradiate, you cannot hold that accelerator for one target production, it is a production exclusive. So, usually the irradiation time will be one day or two hours and so on and the beam time is very costly, cyclotone operations are very costly. Type of decay of radioactors producing reactors mostly beta minus, but in the case of cyclotone produced radioactors which are plus cyclotone. So, they are neutron rich, they are neutron deficient that is the only difference. And the cost of production accordingly in the reactor cost of oxygen is low, but in the accelerator oxygen is very high. So, you have to weigh, you have to optimize the cost also, but when you are delivering to for you know for industry some applications or in hospitals. So, as so that you produced whatever the cost that would go into the another cost of the operation or test. All these factors are important to choose what is that method of. So, you may get a low specific activity in the reactor, but it is cheaper. You want to go for high specific activity in cyclotone, you pay for it that is how you have to assess the situation and plan. Now, many times you know there are many elements have multiple isotopes and you want to produce a particular isotope again gamma or charge particle, but there will be side reactions other isotopes also will interfere, they produce other activity which may not be required. And so, at that point of time you need to have enriched isotope. So, if an element have got multiple isotope and you want to irradiate a particular isotope, you need to get rid of the other which are not useful. So, enriched isotopes are required and the isotope enrichment is a very expensive process. So, that adds the cost to the whole production of the radioisotopes. They are expensive, but at many times they are innovative. You cannot afford to not have the isotopes. So, I will just give you some examples what are the situations in which you needed the isotopes. So, there are situations where you want the radioisotope with high yield and high specific activity, for you know the target atom should contain only radioactivity. At that time you cannot have the other isotopes. You see just a given example 112 India tin n gamma 113 tin. So, you want 113 tin which is used in medicine. Now, the abundance of 112 tin is only 1 percent. You can see here other isotopes of tin will also capture neutron or the volume say 99 percent of the tin is other isotopes. So, if you produce 113 tin, bulk of the tin is still the natural tin. And so, the activity produced of 113 will be very small because 112 is only 1 percent. So, what you do? You try to enrich 112 in the sample so that your specific activity will go up and your high yield also will go up. Similarly, chlorine 18 that you want to produce for pet operations, oxen 18 is very small percentage, 0.2 percent, bulk of the oxen is oxen 16. So, if you radiate natural water, you will get very small activity of F18 because oxen 18 very small abundance. So, what you do? Irradiate you enrich water in so, you have X2O18 and you can irradiate you can enrich oxen 18 up to more than 95 percent. See this is a low mass number. So, it is easy to enrich the low mass elements. So, these are the things you know you necessarily need to enrich the target element in the desired isotope. Second requirement is to minimize contamination from unwanted reactants. You are looking for a particular isotope, but there are other target isotopes which may give you unwanted activity which is not desired. For example, 187 N gamma gives 188 Rehenium. We want 188 Rehenium for our application, but there is another reaction 185 Rehenium N gamma 186 Rehenium which is not required. So, you have one isotope three days, other isotope 17 hours. Abundance of 185 is 37 percent. 187 is 62 percent. So, these are the two reactions concurrently happening. Your isotope of interest is actually 188 Rehenium which is used in therapeutic applications. So, you have to to obtain pure Rehenium 188 you have to allow Rehenium 186 to decay, but how you can allow it to decay? Rehenium 188 is shorter than 186 Rehenium. So, this is not possible to allow 186 Rehenium to decay. Therefore, what you do? You use enriched 187 Rehenium. That is what I was telling that tungsten 188 if you have you can produce by two neutron capture that can give you 188 Rehenium and so, these problems are not there. So, by N gamma root if you produce 188 Rehenium it will be contaminated with 186 which is longer than 188. So, that is that those situations you require necessarily in this isotope. Similarly, again here also this is similar to that radio-nucleic purity means the sample should be pure with regard to particular radio isotope and there can be parallel reactions. For example, you want to get 123 iodine, you irradiate Genon-124 P2N, CGM-123 going to Genon-133 and then by electron capture it goes to iodine-123, but the abundance of Genon-124 is only 0.095. So, if you irradiate natural Genon it has got very low abundance and so, you get very small 1.26 Genon also has got about same abundance as 1.24 Genon and that also gives you by similar reaction 1.26 Genon P2N reaction, 1.25 CGM, electron capture, electron capture 125 and so, this is actually 60 days. So, 125 iodine is longer than 123 iodine and so, it will always contaminate your spectrum. So, if you have 123 iodine produced by Genon-124 P2N reaction, you will invariably have 125 iodine which is longer lived and therefore, there will be always contamination. Therefore, you need to enrich Genon-124 up to more than 99 percent. The gaseous isotopes are easy to enrich, different methods are there believable for isotope enrichment and so, the enrichment of isotopes is a very common technology these days and many vendors are available to supply you in these targets. There are situations where target element may contain isotopes which have very high neutron absorption process. So, you want to produce one isotope of that element, but the other isotopes may have very high neutron absorption process. So, that will they will suppress the neutron flux in the position. So, they act as neutron poisons means though the isotopes which have very high perception for neutron capture, they act as neutron poisons, they will actually absorb the neutrons and reduce the flux. For example, you want 153 samarium for many medical applications, you irradiate 152 samarium n gamma and you get 153 samarium, half life is about 46 hours. But if you see here, you have 149 samarium n gamma, 150 samarium. Though 150 samarium is stable, it will not give you any activity, but the very high perception 41,000 barn of samarium 149 n gamma, it will this high this high perception will reduce the neutron flux. Most of the neutrons will be captured by the 5149 samarium. And so, it will is like a neutron poison. So, it will affect the neutron economy in that position and your yield of 150 samarium will be less. So, these are the reasons where you need to have enriched isotopes. There are other ways also where you can have radioisotopes. I have separated this class of radioisotope because they are very handy in many applications. So, I give you some of the generators, radioisotope generators means you have a parent-daughter relationship, you have a long-lived parent and short-lived daughter and you can. So, you can put in a column or a A is here and you can milk B. So, this is cow, cow, this is called cow, you milk the cow. So, you can hold the parent isotope in the column and you can go on milking discussed in the Merlinum 99 case, you can milk technician from Merlinum generator. They are called radioisotope generators and they are very popular these days because you can send people who are manufacturing these generators, they can sell the generators to hospitals and hospitals have their own hospital radio pharmacy, they can go on milking the isotope of interest. So, Merlinum 99 is the parent of Technica 99M. Technica 799M is the workhorse of nuclear medicine, particularly for the diagnostic departments. So, a spec, single photon emission conflict tomography, you are doing the image of an organ, you inject a leveled compound, compound level with Technica 99M and then when it is going in the blood stream, particularly organ where the blood is flowing, you can take the image of like for example heart imaging, you can see what part of the heart is, if there is a there had been a heart attack, then what part of the heart is infected to us, you can see this one. So, 66 hours and 6 hours ideal transfer equilibrium can go on milking technician from that. Another pair is gallium, germanium 68, gallium 68, say beta plus emitters. So, for pet radio pharmaceuticals, you can use this generator 270 days and 68 minutes, 113 tin and indium 113. Indium 113M is the radio isotope useful for diagnostic radio pharmaceuticals and so you can milk it from 113 tin having applied 115 days and this is 90 minutes. This internal transition, it is not pure gamma emitter like Technica 99M. So, they are ideal for imaging. Stompsome 90, 28 years, mitreum 90, 64 hours and so this is again another pair where mitreum 90 is used in therapeutic radio pharmaceuticals, tungsten 188 decaying to rehenium 188 which is used in therapeutic radio pharmaceuticals and caesium 137, berium 137 used in the laboratory experiments for the gamma ray half light determination and many applications you will find. 137 caesium is also used in blood radiators. So, these are another way of producing. Now, I will just briefly discuss the some of the activities in India. In India, we have the in a cromby campus, we have the Sirus reactor, that goes to start for functioning now, but we have the Dhruva reactor which is producing radio isotopes and there is a sequence of events to irradiate in the reactor, take it to the reticemical laboratory and then process them sent to other agency for distribution in the country. So, inside the Dhruva, we have the reactor hall in Dhruva, inside the reactor hall these are the facilities for experiments, neutron scattering and other things. But inside the reactor, see the electrical entry, inside the reactor we will have the conditions where you can load the sample, radiate them for a specific period of time, take out for processing. So, these are from the irradiation, after the irradiation in the reactor, you bring them to the heart cells. Heart cells are you know, these are the, this you can see the yellow color in the windows, these are led glasses because the inside the heart cells, the radio isotopes of very large activity to curies, hundreds of curies are being handled and the person who are handling them should not get the radiation dose. So, the viewing window is not pure glass, it is made of lead glass. So, lead will, it will renovate the gamma ray, so the personnel are not getting much gamma dose. So, that is why you can see by adding lead, some color will develop in the, and also the radiation was of the radio isotope sources, they also have their, you can see to generate colors in the glass details. So, the viewing window, and these are the master slave manipulators, you can manipulate them and do the chemistry inside the heart cell, you have to open the can, do different chemistry, transfer from one port to other port. So, all these operations are done in the sealed heart cells. This is a complete sequence of radioisotope production, you have the targets, you can have powder, you can put them in the tube and then sealed in the, these are the cans, aluminum cans, you fill the powder into this one and then you can put a cap, you can do welding, irradiate in the reactor, you, this have to go a quality check so that it does not leak. And then you, after this, you bring in the sealed data tasks in the, on the reactor, tell the steel or, you know, parts, lead parts, then they have to be transported to the processing laboratory where the people are now doing operations in the heart cell to separate the particular isotope of interest. They are then dispensed, you can bring it in the vials, properly capping them so that there is no leakage, there has to be a quality check. Many a times the sterility also have to be checked if it is a direct injection to the human being. Then these are packed into the lead parts and then you have the package, you have to give the proper package so that people can identify what is the dose, what is the activity and all that and then these they are supplied to hospitals by the agency. For the charge particle irradiation in our country, we have a medical cyclotron facility at variable energy cyclotron Kolkata, has been commissioned some time back. And the, this will give you proton beams of 30 amoeba and then you can produce these isotopes which are the positon, positon emitters or electron capture between the device slopes like gallium 67, helium 201, at least 123, over in 80, gallium 68 by different types of reactions P2N, P3N, PN, PN, PN reactions. So, I just discussed how they are produced in this discussion. And so, like gallium 67 soft tissue tumor imaging, the gallium 201 for myocardial perfusion imaging after the stress test 123 iodine for thyroid imaging, F184 glucose metabolism and gallium 68 for pet analysis of neuroendoprine tumors. So, these are the kind of activities are being produced at medical cyclotron. And in the country, there are several pet cyclotrons now available, private hospitals have the pet cyclotrons, medical cyclotron for pet isotopes. And particularly F18 is produced in these cyclotrons, you have the 16 amoeba proton beam bombarding H2O18 that gives you F18. And then there is an automated radiochemical processing unit where now within a few seconds or two minutes, you will get the compound labeled with the fluoride. Then it can be directly sent to hospitals for pet imaging. These are the kind of facilities that are available for. So, in our country, the board of radiations and isotope technology is called BRIT. It is the agency to supply different radio isotopes for different kids and they also supply, do the services for industry, in medicine, in the medical industry, normal industry and many other that whoever wants radio isotope in the country, you will find the pharmaceuticals, radio minoc, SA kits, if you want labeled compounds, sealed sources or even technology, radiographic camera, radio chemicals, dogemitry systems, all are supplied by BRIT. You can go to the website of the BRIT and see what are the products they are supplying. And for the larger products, medical products sterilization, processing, vulcanization of rubber and many other, this electron beam processing for installation of tables or consultancy, calibration of radioisotopes, all the facilities, services are provided by BRIT in the country. So, you can go to the website and see what are the things they do. So, I will stop here and thank you very much for your attention. I hope you are getting a feel of what the radioisotopes can do and how you can produce them in our facilities. Thank you very much.