Hello.

Good day, Amal Sibi. I'm Arjun. I've had a look through your background and your professional record. I'm interested

Please start by introducing your professional journey in academia.

Sorry, I can't hear you.

Hello.

Please start by introducing your professional journey in academia.

Yeah. Hi. I am Amal Siddi. I hail from Wayanad, Kerala.

I am a material scientist who is, you know, completing his PSD from IIT Bombay Monash Research Academy.

And it's a joint PhD degree from Monash University, Australia and IIT Bombay.

And.

Yeah, my PhD research focuses on on.

Stress corrosion cracking of temporary biometallic implant materials. I work with magnesium alloys and zinc alloys in a physiological human fluid like environment.

And the focus was on understanding the role of organic molecules like bovine serum albumin and glucose in facilitating or making the alloys susceptible to stress corrosion. Tracking.

Over the years I have been a performance oriented person with 9.44 CPI from my PhD with IAT Bombay and Monash University and around 9.67 during my Masters from NIT Karnataka.

I have had the experience of working on tissue engineering. We developed nano filler for tissue engineering electrospan scaffold materials.

And then my core research areas are on corrosion science and engineering, then tissue engineering again come then advanced characterization then.

Then yeah, I have recently published with Journal of Magnesium and and its Alloys, which is work from my PhD.

And I have attended the Animal European Corrosion Congress.

That was that happened in the year 2024 in Paris, France.

Yep, that's all. That's my introduction.

OK.

Yeah.

Yeah, please. Please continue. Let me hear the whole question, please.

Please go ahead.

Certainly, Professor. The question is: Can you describe the key challenges associated with corrosion resistance in metallic biomaterials designed for implants, and how these challenges influence the material selection and the overall performance of the implant in a biomedical environment?

Oh yeah, certainly. Yeah, yeah. So I would like to cite my work for this as well because.

I can't. I can't. Yeah, yeah, I can't give a broad explanation, but the point is that I have worked with temporary bio.

Please proceed,

A degradable implant materials, so the magnesium alloys and zinc alloys were considered as favorable candidates for it. The biggest challenge that such alloys or let's say any alloy that is used for bio implant related study is that the human body involves.

You know, different types of movement and within the moment there are different types of strains and stresses happening. So it it's it's it's a cyclic process, cyclic fatigue kind of process that is happening so. And during the process, whatever material that we are using to that is administered at the point of fracture, what happens is that if the material has got a higher, uh, you know, Young's modulus than in comparison to that of the bone, the stress shielding effect comes into picture. And when stress shielding effect comes in, there are chances of early, you know, failure and then and, and other associated challenges that is related that is caused you to.

Shielding effect Another process is that since I am dealing with temporary biodegradable implants, it should be in such a way that the material should stay intact or it should resist corrosion till the bone kills and towards by the time the new bone is formed. This particular support system that we have provided provided at the area of fracture should slowly dissolve. This is the key idea behind.

Find the temporary implant material that or material selection or yeah, materials that were used for such applications. So, so prolonging the let's say, let's take for instance, magnesium. Magnesium Millers corrode very fast and there are associated challenges of hydrogen being evolved at a very drastic, you know, pace. So what happens is that this this forms bubbles.

And again it causes inflammation then associated challenges. So in a magnesium alloy system, what is to be done is prolong the particular degradation in such a way that it stays intact till the bone.

Three goes and then it slowly dissolves survey. So this is what I think is, uh, are the challenges with, you know, you know, materials that are used for temporary implant applications, permanent implant applications. We need the, the material to stay intact, you know, permanently. And there we, we only, only point of concern is the stress shielding. So we have to bring down the Young's modulus and bring it down as close to the.

As possible so engineering new materials as as an Ave. that we could try out and people are trying it out in fact, Yep, that's all.

Yeah.

Go on please.

Yep.

Let's expand further: You've mentioned magnesium and zinc alloys as favorable candidates. Could you detail how alloying elements or surface modifications play a role in managing corrosion rates and addressing other performance concerns for these temporary implants?

Yes.

OK. So if you're considering just a bear or a commercially?

Pure magnesium alloy. The biggest challenge there is magnesium corrodes at a very drastic rate.

So people started allowing different, you know, elements into it. Let's say the one that I have worked with is it is ZK 60. So it has got zinc and zirconium along with magnesium. What does it do? It just.

Adds to the, you know, mechanical properties. Under the desirable mechanical properties, let's say a material should have around somewhere close to 300 megapascal, it should it should withstand that much amount of force that has been applied and it should have enough ductility and so on. So the mechanical properties is considered and along with that there is.

As we are adding more you know.

Elements into it there are chances of forming secondary precipitates. The good thing about secondary precipitate is that in certain cases, let's say there are several other aspects to be considered here. But in case of a magnesium alloy, the secondary precipitate form is always cathodic with respect to like likely cathodic with respect to the AA matrix, that is magnesium alpha. Phase.

So what happens is that there are different areas that are cathodic that are relatively cathodic with respect to the.

Alpha magnesium. So what happens is that there are we can we can engineer the minimum in such a way that there are the hydrogen evolution is happening at only certain places.

OK, so that is one way of exploring or using different allowing elements and there are several such researches that are happening worldwide. A recent research is that people have started no, they have realized that the idea of producing you know cathodic secondary precipitate is it is not helping. So they have you know they want. The magnesium alloy to say as PR as possible but.

Then adding a little bit of, let's say, calcium into it and creating certain, uh, you know, engineering the secondary precipitation that, you know, it would, it would have enough strength to withstand that particular stresses and straining during its in its lifetime. And but it should also corrode in not at a very drastic phase, but enough, enough for. Within the time period that we intend.

Another way is developing, you know, biodegradable coating or you know that is biocompatible coating. It should be biocompatible.

And again, the biocompatibility and all sorts of studies should be done in such a way that the key idea is that it should stay intact. This is, let's say this is only for temporary implant applications because I have expertise in temporary implant applications. So yeah.

I hope I have answered your question.

Yeah.

Oh, per se, I don't have experience in I would like to bring it out, but I have enough literature to back out and I can work on it. I am very confident on it. I haven't done, I haven't 3D printed material, but I can do it. That's the point. So coming to the point I wanted to, I want to put for this that you could try different, different ways by which you know you could, there are different 3D printing methods.

Could you elaborate on your experience or approach in developing 3D-printed hip and knee implants, particularly focusing on how you ensure their mechanical integrity and biocompatibility?

That has been developed all the time. So you could you could use one of the methods, let's say laser bed fusion powder, laser powder bed fusion method or selective laser melting kind of method and you develop the alloy in such a way.

The biggest point that we have to take is that when we are bringing in new material which is different from the already available material, the current research focus is on bringing down the the Young's modulus so that it will be as close to the bone as possible. There comes in the texture analysis part, you should be able to.

You know, change the directions in which the in which the.

You know the alloy has been printed or the 3D printing works and and you know at different certain in different crystallographic directions. You you should you should I would say not in different texture orientations. You can try to understand the mechanical property and fix a particular or you reach a conclusion.

Along with this sorry.

Please continue.

Corrosion studies, then you move to biocompatibility studies. So this is how I would approach. So initial 3D printing is to is to optimize, optimize the alloy in such a way that you know you get the best properties out of it. So that is how I would approach. That is how I really want to move forward, which is one of my research goals at the moment. My research goal is to develop a new set of alloys that has got.

Yeah, along with such studies and then you, let's say you develop a particular, you realize that at this particular texture orientation, you're getting the best mechanical properties, then you move to.

Lower Young's modulus.

Yeah.

I hope I have answered the question.

Yes, Professor, you've outlined a thoughtful and methodical approach to developing 3D-printed implants, focusing on mechanical optimization, corrosion, and biocompatibility studies. Thank you for sharing that. Next, let's examine your perspective on advanced coatings and how they can address tribocorrosion issues in implant applications. Can you provide insights based on your experience or research knowledge?

And then the uniformity of the coating matters. If it is too much for us, there are chances of you know the the aqueous environment to sleep in and then the electrochemical reactions to happen and then corrosion to happen. So you have to you should be able to cater to the porosity that is within the coating. But then there is no perfect coating. All coatings will have cores. So you should be able to engineer the porosity that is that is within the. Within that.

Tribo corrosion. I have been worked on tribal corrosion. My work is mostly on aqueous corrosion and the I I have not developed a coating for it, but people in within the group has developed and I've got exposed it to such research. So from that what I have understood is that that the the method by which you apply the coating matters.

That is.

That is, you know, considered during your applying this particular coating. And so the method of application methods you have to do enough research to come to a particular conclusion that OK, let's say this particular method will help. OK. Secondly, in terms of striber corrosion, I am not an expert in tribal corrosion, so I don't think I'll be able to answer with respect to. Driver corrosion because I haven't performed experiments in tribal corrosion studies.

But I deciveness of the quoting also this is what my insiders how adhesive the coating is should matter in Tribo corrosion because yeah, that's what I believe, but I'm not sure, sorry.

Understood, Professor. Thank you for detailing the importance of coating application methods, porosity control, and adhesion. Your reflections on related research are appreciated even if tribocorrosion isn't your specific area of expertise. Let's now evaluate your contributions in the area of replacing animal models with in vitro models for implant testing. Can you share your understanding or involvement in developing such models aligned with the broader goals you've mentioned?

Yeah, so.

The the.

The methodology that we have been, I mean, the, the experimental procedure that we have been for following there are Monash involves a tank in which which serves as a, you know, water bath. And into that you, you, you just, there is another reservoir where you fill in the, the, the simulated body fluid with several adhesions and you pump this particular simulated body fluid, you keep it at the temperature of the.

Please

That is like 37°C and then you keep on pumping it through through different pipes. And then you just bring it to the to the area where the test sample is gripped. And then you set the cell in across it so that the test sample will always be immersed within the material with the material will be exposed to the environment that we intend and then and then it is pumped out.

Again and then this particular pump in and pump pumping out happens so that simulates the way how the blood is flowing in through the the body. Another point is that the way so similar that body fluids earlier involved you know one type of solution is the Kokubo solution, another you know the hand solution and then there are several types of simulated body fluids that we have been.

In all these cases, the pH regulation which matters some a lot, so pH regulation was done using buffering agents like Hepas or Trust. And these were studied and they it was understood that this particular, you know, the pH buffering agents were causing more corrosion to happen by consuming more oh.

Minus ions within the.

Within the system. So the whatever you know.

Corrosion rates that we were getting were, you know, were accelerated. So the development that we had, in fact it was run by one of my predecessor seniors, I would say is that they developed a system where carbon dioxide gas was, you know, carbon dioxide bicarbonate buffering system was installed in such a way that, you know, the buffering will happen when the pH drops and then sorry, when the pH goes up the carbon dioxide gases, you know it's.

Will it will move in and then PS will come down and then this then the valve will close then PS will again come up when the electrochemical process happens or the the when they allow the roads and then again this particular pH regulation happens. This is one way we were we were trying to, you know, simulate the human body like environment with pH regulation, temperature regulation. Another point is adding in different types of molecules that.

Human body, there are several types of proteins and you know, molecules within the human body. So we we were not able to use every kind of them, but we have tried using bovine serum albumin which simulates the albumin content of the human blood and glucose obviously glucose, everybody has got glucose in their body. We have tried to understand. So albumin part we have you know mentioned and it was studied and you know, it was very well. Documented and explained in the paper that we have published with journal.

Around within the.

Magnesium alloys, glucose, fat as well. Then there is the synergic influence. Synergistic influence of both protein and glucose.

Whatever studies that we have done just gives an initial idea where we since the protein content was too much, we were seeing similar type of behavior in.

In in no hands plus protein, hands plus protein plus glucose, which is an aspect that is to be, you know, that is for future research that I have, you know, I have put that particular point in future research goals within my PhD thesis as well. So I would like to take that up and then, you know, learn the different interactions of ions. How does it affect the, you know, chemical reactivity or biocompatibility or the way how osteoblast cells.

Will come and you know, adhere to the surface and how so and so the the ossification so and so on. So these are new avenues for me to explore and I would like to collaborate with the expert experts within the department and learn the ways by which how results was done with the supervision of the expert within the department. So these are some avenues that I would like to try out as well. Yeah.

Thank you, Professor. You've shed light on the systematic development and refinement of in vitro models, addressing dynamic pH regulation, protein interactions, and biomimetic conditions. Your detailed explanation highlights critical aspects for implant testing. Let us now move towards your ability to guide student projects and conduct evaluations. Could you elaborate on your teaching philosophy and the approach you take to mentor students effectively?

Yeah, see, I really believe that people or the students should, should learn.

With hands on experience should learn from with hands on experience, they should be given tutorials and case studies with references from literature to learn what is actually happening in a global perspective and different labs and so and so so I really believe in hands on experience. Second, philosophy is application first always if something.

Please continue.

So let's say clinical application. If some material has to be, if some material has to be developed, it should have an application.

And so I really want the students to learn the different applications where this particular material are are is used in another philosophy is continuous learning. I really want the students to learn even after, even from the theories of this, the theory that I've covered within the with the subject. But I, I want them to learn the other aspect that has been, you know, handled by different people across. The Globe.

And then, you know, and inculcate that within their research that they, they would do within as a part of the curriculum. So I really want to bring in tutorials. So and so and, and so I would like to bring in the, my global exposure that I had, uh, in the while I was working as a teaching assistant or I would say they term it as masters assistant demonstrator. So I was helping students with tutorials and so on. And so, so.

Uh, so I had the, I had, I was able to interact with students across the globe. So that is a global perspective that I've acquired. From there, I would like to bring it to the curriculum in the teaching that I would be performing there at VIT. And then what else? Yeah, I think that's all. I think that's all Mostly I want the students to learn from, from. By performing the the tests so and so.

They have to learn, they should have a hands on, uh, experience. That's what I want them Theory should be there, but then you need to know what you're doing. Only then they can become really good engineers. I mean, only then they, they'll have the intuition to.

To, to, you know, to think, OK, this is happening. Then I, I think, I think this, this particular group has done this so and so work so I can I can think about that and then so on. So they should have the intuition, they should have the way how the research approach also should be taught in classes. That's what I believe.

Understood, Professor. Thank you for sharing your teaching philosophy. You've emphasized key aspects such as hands-on experience, application-driven learning, continuous development, and fostering a global perspective—valuable principles for cultivating capable engineers and researchers. Now, let's dive into your ability to develop orthopaedic, dental, and cardiovascular indigenous implants. Could you provide some insights into your vision and approach for advancing these areas?

I'm, I'm quoting the, I'm citing the same thing that I've talked talked earlier. I really want to delve into developing better magnesium materials. But then again, there are several challenges that are associated with 3D bioprinting or 3D printing.

Yeah, so.

Like porosity, let's say there are several structural problems that may, uh, that, that inclusion, say, for example, the, the chances of inclusion formation, so and so, so all those things should be, you know, should be understood. And then so the idea is to develop a magnesium alloy. That would degrade within the time frame that we have in mind, let's say within a couple of months.

Or within certain days.

We we should be able to control that another one, another set of alloys that has been dealt with presently is zinc alloys. The biggest challenge with zinc alloys are their mechanical properties. Mechanical properties of zinc alloys are not enough.

We should be able to.

Let's say it should be within 300 MPA. It does not, it does not have enough, you know strength and ductility that is that is required for such application. So we should engineer Zynq alloys with allowing additions in such a way that first thing their mechanical properties should be at par. The corrosion in property is not that big of a deal. I would say the corrosion is is not as aggressive as magnesium alloy, but then developing and coating also.

Would be better for sync alloys then?

And a primary idea that we have to think about is like we have to bring down the elastic modulus by the by selecting.

The the right, you know, allowing addition that we have. So we have to play along with the alloy and then, you know, develop certain combination of, of elements that could be added to Zync in such a way that, you know, the elastic modulus also could be brought on. Because the one that I have worked, it's a magnesium 1 copper one.

Zinc 11 Copper one magnesium alloy, so the.

There again and the mechanical properties were not because it's an *** were not that good it was an ask allow then comes you know the next step for that which I have proposed within within my results is is is performing thermal mechanical you know treatment where whereby the ductility and strength would be increased. So yeah.

The elastic modulus is very high, so.

There are several avenues that I, I really want to move into A basic idea is I really want to develop a new set of alloy which could be used and I really want to provide enough data for future researchers to, you know, develop better alloys in in in future because.

They move to other lean magnesium alloys. All these are within within, you know, magnesium system. So I'm citing magnesium because magnesium is what I've worked with. So again, aluminum addition is is not that welcoming. So they have moved into other, you know, allowing elements. So, so we really have to.

We started with aluminum additions. Aluminum was found to cause Alzheimer's, so again.

Think about what type of materials that elements that will be used for allowing.

And develop better alloys that could be, you know, future candidates. So that's my idea, that's my future goal and.

Yeah, I really want to continue a set of research that I have.

Proposed for future research within my PS3 thesis. So I really want to continue with that and then and then inculcate or inculcate certain learnings that I'll get from the research experts within the department and then, you know, explore new avenues. I have always, I really wanted to delve into cell culture studies and you know. You know.