User Interview: Research Group Ray at the Humboldt-University Berlin

anvajo: Dear Mr Kass, thank you very much for taking the time for an interview. Would you like to introduce yourself?

Mr Kass: My name is Dustin Kass. I work at the Humboldt University in Berlin in Prof. Dr Ray's research group. There are about ten of us at the moment and we are mainly working on organometallic chemistry, in particular on the functionality and reactions of enzymes with the aim of reproducing them synthetically and making them usable for industry and chemical syntheses. Currently, I am also writing my doctoral thesis on the topic of "Synergetic effects in the activation of small molecules", using oxygen. In my research group, some of my colleagues also work on oxygen activation and the others work with water, carbon dioxide or carbon monoxide. Their chemistry also runs through our UV-VIS device to follow the colouration of the complexes.

anvajo: That means that all colleagues in the working group use a UV-VIS device and thus potentially also the fluidlab R-300?

Mr Kass: They are not all working with this device yet, but sooner or later they will all have to use a similar device. The fluidlab is only a VIS for now. We have several large UV-VIS units that are permanently installed and used for special applications. With the fluidlab R-300, we hope to be able to make everything more mobile, in case you need to do something outside your own lab or for situations, like the glove box, where the big devices do not fit. But in our working group, everyone has to look at the colours of the complexes, there's no getting around that.

anvajo: That's already a good prospect for the fluidlab R-300. What do you mean by the glove box?

Mr Kass: We have been planning to do reactions in our glove box for a while. We have these boxes so that we can work in the absence of oxygen and water. This is necessary because most substances just react with oxygen without being able to control this. If other small molecules besides oxygen are to be activated, such as carbon dioxide or carbon monoxide, this can also be done in the glove box. This has advantages because nothing can get out of the box and the reaction can take place in a controlled way. This is the top application example we envision for the future. As soon as we put a gas that is not oxygen on our complexes in the glove box, we can observe how and at what rate the spectrum changes, which is what the fluidlab is very good for.

anvajo: A very exciting field of application for the fluidlab R-300! Do you do other things with our laboratory device?

Mr Kass: We think so too. Another application, which has already taken place, would be the use of the fluidlab when we are not in our laboratories and do not have the possibility to measure on the large, permanently installed measuring devices. For example, we prepare samples, mostly on the large UV-VIS devices, which means we start the reaction there and observe how the colour changes. If it has the colour we want and is therefore the species we need, other spectroscopy methods are used. For this, we again need other analytical equipment, which is located in other universities and thus requires a long journey. Before the measurements in other universities, it is helpful to be able to check whether the sample is still what we need. If it is now possible to take the fluidlab with us to where the next measurement will take place, we can check on site whether something has changed in the sample or whether the values have remained the same. So the fluidlab R-300 saves us a lot of time, effort and sometimes we know exactly what triggered the change in the sample, so that the right conclusions can be drawn directly.

anvajo: So, you could summarise, the fluidlab R-300 is a great lab product because it can be used portably outside the lab and is also well stored in a glove box?

Mr Kass: Exactly, the other measuring instruments are big boxes that cannot just be taken along. That is the big advantage of the fluidlab. As far as performance is concerned, the fluidlab R-300 is also absolutely sufficient. The large measuring devices cannot do much more in the VIS range than the fluidlab R-300, except for the UV range, which the fluidlab does not cover.

anvajo: That is very nice feedback, thank you! Is there anything more that you have tested with the fluidlab?

Mr Kass: Yes, for us titrations are another possibility to use the fluidlab R-300 and we have already tried that. We placed the fluidlab on a magnetic stirrer and then put it into operation. That worked very well. With the magnet in the cuvette, it rotated and mixed the solution well. We were also able to add other solutions, which then reacted with the solution in the flask. Based on the colour change, the kinetics, the change in the curve could be observed with the fluidlab analogue from the time the additional solution was added.

anvajo: Do you have an example of the reagents you worked with?

Mr Kass: I added an oxidising agent to an iron complex, which turned the whole solution blue because the species that forms from the iron and oxygen is blue and has an absorption maximum at 690 nm. I then added a substance that absorbs oxygen. This was triphenylphosphine. Then it became visible that triphenylphosphine reacts with the blue species at 690 nm. It became visible because of the exponentially decreasing absorption band at 690 nm.

anvajo: But that is also a reaction done under the glove box, right? Can you describe the work with the fluidlab R-300 once in the glove box?

Mr Kass: With pleasure. I have to admit that at the beginning I was sceptical whether the fluidlab R-300 would work in the glove box the way we wanted it to. On the one hand, the introduction of the fluidlab R-300 into the glove box was a critical point, because there is a special sluice for it so that no oxygen is introduced. In this airlock you have to vacuum everything and then you put nitrogen into the airlock, with which the box is also filled. At first we were not sure if the fluidlab would survive the vacuum, because it could have burst under vacuum. However, the worries were unfounded and the vacuum was not a problem. Another disturbing factor that could have made working with the fluidlab R-300 impossible is the operation in the glove box, as not only the thicker gloves of the glove box itself, but usually also overgloves have to be worn. Fortunately, even with the triple gloves it still worked to operate the touchscreen, so we had no problems.

anvajo: How does it work with other devices in the glove box?

Mr Kass: Most UV-VIS devices are difficult to fit in a glove box. I honestly do not know if other groups have this, but I have not come across it so far. Usually, large devices have to be placed directly in the glove box when it is assembled, because power and internet connections have to be made. In retrospect, this is always very difficult to implement. That is why it was a positive surprise for us that we could simply sneak in the small fluidlab R-300.

anvajo: That means the WLAN function or the connection of the fluidlab with the datalab on the computer is used by you in the glove box and works well?

Mr Kass: Yes! So far I had only tried it once, because the kinetics mode was still in the test phase. I created a hotspot with my mobile phone and it worked very well to transfer it to my laptop.

anvajo: What about magnetic field measurements? Are these also carried out by you?

Mr Kass: That is an idea for the future so far. We have several devices that have a large electromagnet that can be set to a certain magnetic field. With these electromagnets you always have an area in which the magnetic field is homogeneous. The idea is to place the fluidlab there in a weak magnetic field. Reactions are then to be carried out in this magnetic field. The background to this is that the application of a magnetic field can cause different states in the reactions to behave differently in terms of energy. For this reason, there are changes in the reaction rates. They are either favoured or slowed down in the magnetic field. This acceleration or deceleration of the reaction can be observed by the fact that the colour, at a certain speed, changes. We would like to use the fluidlab R-300 for this, but we will have to investigate this further soon to see if it is possible.

anvajo: That sounds like a good outlook for the future. Have there been any problems with the fluidlab R-300?

Mr Kass: No, there were no problems. We are satisfied with the handy device. Even in the quality of the spectra, there was no difference to the large devices, at least not in the range in which the fluidlab measures.

anvajo: In retrospect, would you choose the fluidlab again?

Mr Kass: Yes, definitely. In the end, we decided to buy it after our free test phase.

anvajo: Thank you very much for the nice conversation and good luck for your future work!