Impregnation of silver nanoparticles in cellulose for water purification


The Dopper Changemaker Challenge started in 2017 in the Netherlands. This year, it took place in Kathmandu along with other popular European cities including Amsterdam, Berlin, and London. The final of this international competition was held on 15th June Saturday not only in Kathmandu but also in Amsterdam, London, and Berlin. In total 445 students from all over the world applied to get a chance to win the title of Changemaker 2019.

One of the ten finalists of Dopper Changemaker Challenge in Nepal, Kanchan Pathak, shares with us what her thesis was about and her overall experience at Dopper. Read on to find out more.


1. Could you introduce yourself and your project?
I’m currently doing my Masters in Chemistry from Amrit Science Campus, the same place I completed my Bachelors from. The reason I applied for the Dopper Changemaker Challenge was to get funding for my research project. I had something else planned that wouldn’t require a lot of funding and could be done inside the college laboratory but when the application for this challenge opened, I revised my project and made it a bit advanced because, if selected, I would get funding to complete it. 

My thesis is titled Impregnation of silver nanoparticles in cellulose for water purification. The idea is to incorporate silver nitrate in traditional Lokta paper and check its effectiveness as a water filter. I specifically used Lokta paper because it’s a traditional Nepali paper that can be found easily plus has the properties of keeping microorganisms away, making the filtration better.

2. So did you make a prototype after getting the fund? How did you go on about it?
I made two specimens and checked their effectiveness and zone of inhibition, which is basically a method through which we can find out how much microorganisms can be defeated by certain antibiotics. To do this, I took a small piece of the filter paper then I placed it on a plate full of microorganisms for 24 hours and observed its effectiveness.

3. How was your overall experience at the Dopper Changemaker Challenge? Did you get to connect with fellow batchmates?
One of the projects that was similar to mine was that of Amrit Regmi so I was in contact with him on a regular basis to discuss ideas and progress on our researches. Through the challenge, I also got to improve my pitching skills which I was terrible at in the start. So, we had this mock pitch where we had to talk about our project in front of everyone for under a minute. Honestly, I thought that my pitch was the worst as I was both nervous and scared. However, after guidance from Bivishika, Anju and Shilshila Ma’am, I got to improve on my pitch and during the semi-final pitch, I felt confident and was able to deliver myself better. 

Also, rather than an experience, I feel humbled to have been selected as a finalist at Dopper Changemaker Challenge. This eventually helped me get into National Institute of Material Science, Japan for a three months internship where I have been able to do characterization and use technologies unavailable in Nepal.

4. What was your push factor? Would you like to mention people that helped you with the project?
The first time Anju came to my college to inform about the challenge, I wasn’t sure if I should apply. One of my teachers, Mr. Hari Bhakta Oli encouraged me to submit my project because he already knew about it. However, I was hesitant about submitting this idea because I had applied in another competition which had made me obliged to not submit the same idea anywhere else. But, Hari Sir gave me an idea to change the research a little bit so that it’s not the same and not too different from the initial concept too. So, that was great help from his side. 

My supervisor Prof. Dr. Raja Ram Pradhananga also supported me throughout the challenge. He even provided me with silver nitrate, which is a very expensive compound, to test my research even before I had gotten the funds from Dopper. I think that pushed me to work harder too because I realized that people believed in my capability.

5. What do you think would have made the challenge even better?
The challenge was only open to students currently doing their Bachelor or Master studies. There are so many Master graduates who weren’t able to conduct a proper research because of lack of funds and resources which they could’ve gotten from Dopper Changemaker Challenge. So, keeping this criterion open could’ve made the challenge more inclusive of even better research ideas, I think.

6. How can your project make an impact?
Most of us drink water from the Jars that we get in the market, at least the middle-class people. Most of the water is contaminated with E.coli, which is one of the major host of water borne diseases. And since the water filtration process is expensive, people can benefit from it. This project gets financial support and the Lokta paper filters are attached to the Jars. 

Although silver nitrate is expensive, we only need less concentration of it in the cellulose. So, if we produce in mass then this could become affordable for all.

7. What are your future plans with the project?
Right now, I’m focused on gaining more knowledge and experimenting. I’ll test and see how the initial processes turn out to be then if I get funds to carry on the project, maybe I’ll prototype and bring the product to Nepal. But, until then it’s just an idea that needs testing.

8. What were the challenges while conducting your research here?
It’s very difficult to get access to labs in Nepal. Sometimes, we need to conduct a 24 hours continuous experiment, but the rules and regulation restrict us to do so. Plus, there’s always technology and resource constraints. After coming to Japan, I have realized that there are so many opportunities for researchers here since they are acquainted with amazing technology.

9. Is your idea new in Nepal or has it been done before too?
I don’t know about unpublished articles but my idea is fairly new in Nepal in terms of published articles. As for those abroad, there are similar published researches but what brings novelty to my research is the use of traditional Nepali Lokta paper.

For more information about her thesis, please connect with Kanchan Pathak at 

Interviewed and article by Yangzum Lama