Innovate in the UK: Hands-On with OMNISEC and Insights from MP Applications Group

by Serena Agostini, Thursday, 19th December 2024

Who knew science could be fun! Oh well, I bet many scientists have said that already… Are we geeks? Potentially! But this summer was fun for us at Malvern Panalytical (MP) in the UK Applications group thanks to Maria Sbacchi, a PhD student from University of Trieste, Italy. She gave us the opportunity to contribute and help her in her amazing PhD research project on the exploitation of Carbon NanoDots (CNDs)[1] as building blocks for protocell synthesis. Protocells are microcompartments, or synthetic cell-like entities, that mimic key biological functions, such as compartmentalization, selective permeability, and catalytic activity. Engineering microcompartments to exhibit life-like behaviours is one of the major challenges for bottom-up synthetic biology and nanotechnology, bioinspired tissue engineering and microscale engineering of soft machines and devices.

Yes, we do like collaborations with our customers. It gives us the opportunity to stay in touch with the latest scientific research, and we appreciate seeing the value that our instruments bring to that research. Maria showed us how the OMNISEC multi-detector GPC/SEC system (OMNISEC | Multi-detector GPC SEC System | Malvern Panalytical) is an important piece of the puzzle in the development of new nanomaterials and synthetic cell-like entities, protocells, for the development of synthetic artificial tissue-like systems (prototissues) based on the assembly of protocells.[2] Figure 1 is a simple representation of part of Maria’s PhD work, employing CNDs to form colloidosomes, a category of protocells defined as microcapsules whose shells are composed of colloidal particles. OMNISEC multi-detector system entered the scene by helping with the characterization of the CNDs, the PNIPAAm based polymers involved, and the finial CND/polymer nanoconjugates. In addition, SEC analysis was also carried out to analyse BSA and its conjugates with polymers, utilized for the more typical type of colloidosomes composed of protein-based nanocomposites.[3]

Figure 1: Schematic representation of the use of CNDs and polymers for the formation of colloidosomes.

Everything started with a typical sample analysis request, a project for the demonstration of the capabilities of OMNISEC multi-detector system, driven by our Italian distributor Alfatest. The samples, coming from the group of Prof. Pierangelo Gobbo and Prof. Maurizio Prato at the University of Trieste, were challenging: the SEC run conditions were unknown, and sample chemical nature and behaviour were a bit of a mystery. However, by putting together our expertise in chromatography and the deep sample knowledge of the scientists in Trieste, we managed to get some good results. The data was well received, and Prof. Gobbo got an OMNISEC system for himself. But the road was still full of uncertainties and that is when Maria came to us in the UK Applications group, and the story begins.

Maria joined the Applications group in Malvern on an internship of three months, fully funded by the University of Trieste. She enjoyed her time with us, despite the cold that prevailed at the beginning of summer (and believe me, for an Italian the English summer is just late winter really!). She got to visit the towns of Malvern and Worcester with us, and we even showed her our penguins! You read it right! One penguin even accepted to pose with us in the group photo below (Figure 2). Would you believe it was taken at the beginning of August? Jumpers and sweaters are always a must in the UK. There we are, the friendly Applications group of Malvern Panalytical, surrounding Maria and the penguin in the centre (The Great Waddle of Worcester 2024 | St Richard’s Hospice, a charity event for which MP contributed with our very own sponsored penguin: Calvin The Copperplate Penguin!).

Figure 2: MP Applications group and Maria from University of Trieste, Italy, in Worcester, UK.

Maria brought us new science to think about, and we welcomed her by putting our instruments at her disposal and by helping her with our knowledge to achieve the best results for her PhD project. She learnt a lot about the OMNISEC system, and we taught her how to use it to achieve the best results. We spent days together thinking about what could cause strange chromatograms we did not expect. Why is the chromatogram flat, where is the sample? Oh, our good old friends sample/solvent/column interactions, what a pain they can be. And what about the unstable sample precipitating in our injection system? When we say “Sample preparation is important!” it is not a joke. “Don’t inject unstable samples!” and guess what, Maria’s samples were thermosensitive. Thankfully we have a temperature controlled autosampler with OMNISEC to help with this situation.

And so our search for the right mobile phase to use in the OMNISEC system started, and the Zetasizer came to help. Zeta potential measurements helped us to find a good salts combination to use as a mobile phase in the OMNISEC. Seeing the zeta potential of her sample changing with changing salts was very helpful and we understood why our chromatogram was a flat baseline for some of her samples. Running a negatively charged sample on a cationic column is not advisable, but who knew we were doing it prior zeta potential measurements!? And we kept going with our tests, struggles and successes that led us to the best conditions we could find to analyse BSA and its conjugates with polymers, CNDs and their conjugates.

We also got to use the OMNISEC for compositional analysis, and Maria was happy to see that she had been successful in synthesizing her samples in her research lab. An example of compositional analysis of a BSA conjugate sample is shown in Figure 3.  Soon Maria will be able to finish her PhD thesis and publish some exciting papers on these materials and tests we have done together!

Figure 3: On the left, multi-detection chromatograms of a conjugate of BSA/PNIPAAm conjugates. On the right, Derived Data view with RI chromatogram and concentration profiles of BSA and the polymer.

Whilst with us, Maria also had the opportunity to attend two customer trainings at the Malvern site (Training, Application and Expertise Services | Malvern Panalytical), one with the Separation team for OMNISEC, and the second with the Dynamic Light Scattering team for Zetasizer (Zetasizer | Expert Light Scattering Instruments | Malvern Panalytical).

Finally, a special thanks goes to all the people and parties that made all this possible: Alfatest, by putting us in touch with the research group at the University of Trieste, Maria’s supervisors Prof. Maurizio Prato and Prof. Pierangelo Gobbo, the funding from Maria’s PhD, and our Applications group managers and the people in the group that were super welcoming. And of course, thanks to Maria for coming here and sharing her research with all of us.

References:

  1. “The Importance of the Purification Step and the Characterization of the Products in the Synthesis of Carbon Nanodots” Beatrice Bartolomei, Maurizio Prato, Small 2023, 19, 2206714
  2. “Programmed assembly of synthetic protocells into thermoresponsive prototissues”, Pierangelo Gobbo et al., Nature Materials, 17, 1145-1153 (2018)   
  3. “A floating mold technique for the programmed assembly of protocells into protocellular materials capable of non-equilibrium biochemical sensing” A. Galanti, R. O. Moreno-Tortolero, R. Azad, S. Cross, S. Davis, P. Gobbo*, Adv. Mater., 33 (2021)

Links:

Contact Us