Tag Archives: Engineering

Molly Monk and Issy Bolton at the University of Bath

Pawan Jolly, Molly and Issy

Photo: Issy and Molly with Pawan Jolly in the department of electronic & electrical engineering 

Within the department we were working with the Biosensor group. During our time there we were given lots of opportunities organised by our supervisor, Pawan Jolly, to experience and learn about research science. We visited chemistry, electronics and the nanofabrication labs and were kindly shown around by other post graduates who explained to us their work. It was very interesting to know how the researchers were working on the development of diagnostic tools for cancer diagnosis where one of the main focus was Prostate Cancer (PCa) diagnosis. It was also fascinating how the different groups around the Europe has come together on a common platform to work on the diagnosis of PCa and the network was called PROSENSE (http://www.prosense-itn.eu/).

Within the PROSENSE project, we individually fabricated DNA based biosensor for PCa, observed the absorbance of light by gold nanoparticles using spectrophotometer and used localised surface plasmon resonance technique (LSPR) among other things.

On the 24th Aug 2015, we started with preparation of buffers namely trisma base and sodium acetate and a bovine serum albumin (BSA) as a protein for our biosensor. The next day we adjusted the pH of the buffer using a pH meter, which detects the ion concentration of a solution, to raise or lower the pH of the buffers  bases and acids were used.

As we were working with DNA, everything used must be extremely clean. So first we prepared our gold working electrodes by cleaning it using techniques like sonication, polishing with aluminium oxide in a figure of eight motion. As we wanted our surface to be very clean, electrochemical cleaning was performed in sulphuric acid as an electrolyte with a three electrode configuration using cyclic voltammetry. The silver reference electrode is kept in a salt bridge in order to protect it from the acid, the platinum counter electrode goes straight into the solution and the gold working electrode again goes into the solution. The electrode are connected up to a potentiostat that will cycle a voltage through them and causes oxidation and reduction of the gold surface and hence, removes dirt from the surface of the working electrode. In our experiment the next step was to fill caps with a light sensitive solution together with probe (receptors to capture DNA) and electrode was dipped in it, they were then left overnight.

Next we produced two separate electrolytes using potassium(II) hexacyanoferrate and potassium(III) hexacyanoferrate salts mixed with our prepared buffer solution. Then we placed our electrodes into the same buffer solution that was being used in our electrolytes. Firstly for each electrode we carried out cyclic voltammetry again. After the first run some of the electrodes had DNA attached and the others had a protein attached and depending on the length of time the electrodes were allowed to sit in the solution they should decrease the oxidation peaks as they interfere with the flow of electrons. We also carried out the programme electrochemical impedance spectroscopy (EIS) which measures the amount of resistance of the system  this is affected by not only the surface modification because of binding but also the ion concentration in the electrolyte. With capture of DNA, we observed the increase in resistance and also the decrease in the oxidation peaks in the CV. By the end, we successfully developed our own DNA based biosensor for detection of circulating DNA in blood for Prostate cancer.

All in all, we had a great time and can’t thank enough everyone who took the time to talk to us about their respective fields. Most of all a massive thanks to Pawan, for having the patience of a saint and showing us the “realities” of research in the field of science.

A Day In The Life Of An Engineer in A Busy Construction Site

by Victor Macauley

Victor pic 1I was placed at the Crossrail C520 Custom House Station Project, which is getting to the close to its finishing date. I learnt how the engineers correlate the designs they get on the building site by using surveying instruments such as a theodolite with a rotating telescope which is used for measuring angles both horizontally and vertically. It is an important tool in ensuring that the on-site projects fit in with the design measurements as it can give a high amount of accuracy. Firstly you set up markers around the area and then lock on to it on using the theodolite and then point the laser to the point you want to measure on the screen it will give you the distance from the marker that the object is.

Glass cladding being placed on a lift shaft
Glass Cladding being placed on a lift shaft

Furthermore I was placed with an Engineer in a managing role as a Package Planner named Damien, whose role was to be on site and liaise with all the workers ensuring that there doing the right work. On this particular occasion one of the contractors, a firm dealing with lift installations, came to survey the lift shafts. The following conversation between Damien and the  representatives was a really interesting one where they were talking about the issues with the lift shaft. Damien had to use his creativity and knowledge to come to solutions for the representatives, as they were worried that their lift might get damaged when installing. That little meeting gave me a great insight  in what engineers in managerial roles have to be able to do.

I really enjoyed my week with the Liang O’Rourke team at Custom House and my experiences there, from gaining valuable knowledge on the pathways to engineering from the engineers and what the engineers are expected to do – for example providing task sheets to the workers showing them how to use machinery safely and efficiently, as safety and ethics is of huge importance for Liang O’Rourke and Crossrail.

Experiencing a week on a construction site has made me want to get into engineering more and try to get more real world experience of engineering in action.

Victor undertook a week-long placement at the Laing O’Rourke Custom House Station project, part of the Crossrail project.