1. Extraction of caffeine
By Ryan McTeer
By Ryan mcteer

2. Preparation
To start my project I needed to develop a good research topic. To do this I had to brainstorm for different ideas. I composed a small list of key words and topics which interested me, and also topics that I was able to understand and read the key points of literature that goes into research with projects. To ensure the success of my project I had to ensure that the topic I had chosen to take on is manageable and that material is readily available though internet and the university. At the same time however I also needed to be flexible with the topic, as I understand the implications of taking on a large scale experiment and that their will be chance of errors and equipment failure etc.

3. Preparation
The focused topic in which I decided to study for my project was caffeine in order to use caffeine as an experiment I needed a research question that would link the practical and theory together so I designed and implemented an experiment to determine the caffeine contents in various brands of tea using a (HPLC) High-performance liquid chromatography machine.

4. Plan
When I had come up with my research question I then needed to make an experiment that would test the overall change in the independent variable. The independent variable that I would change for my experiment was the different brands of tea. I did this to measure the overall impact of the change of tea has on the caffeine level. During the experiment I used a HPLC machine this then allowed for me to tell the different levels of caffeine in each brand easily and more importantly accurately. To guarantee a fair test I only changed the independent variable. I chose to run through my experiment three times to ensure that the different results that I obtain are reliable as any errors can be spotted and recorded as anomalies.

5. Research
To help me understand the project and what I was taking on I researched caffeine and how it effects the body. From my research I found out that caffeine is a form of stimulate. Caffeine uses the nervous system and skeletal system. This then effects the body in different ways for example an amplified alertness, this will then lead to the body having a greatly increased ability to focus. However this is only for a short period of time before the effects wear off. As well as having an increased ability in focus, the caffeine will help with keeping the body awake as the nervous system is more awake. Although taking excess amounts of caffeine regularly can lead to insomnia and being bad tempered

6. Research
During my research I found out that HPLC was a much more desirable separation technique for identification of chemical components in my case the caffeine molecule. For my experiment I acquired 3 different tea samples from a Asda. I then measured out and labelled the samples to their specific brand. I had developed a method for the caffeine extraction this used the HPLC machine. The method I used was called column extraction. The resulted extracts were concentrated then injected in HPLC equipped with ultra violet detector. The quantitative results when compared with reference standard for caffeine. Up to 400 mg of caffeine a day appears to be safe for most healthy adults. That's roughly the amount of caffeine in four cups of brewed coffee,

7. Planning
To ensure that my experiment go's according to plan and that I can reduce overall errors. I prepared a detailed method for the extraction of caffeine. This meant that the reliability from beginning to end would be very consistent. I had planned to write this experiment in a way in which someone else could come and test my experiment. So if they are fascinated in seeing how my results were obtained they could then follow back through the procedures and see for themselves.

8. Gantt chart
To get my time management correct I used software called Gantt chart. This is a tool that offers a chart schedule, this keeps all of my tasks and helps me manage them into certain time periods for the project to be completed for a certain deadline date.

9. Carrying out experiment
In order to do my experiment safely I needed to produce a COSHH form this brought to light any issues or complications I would have during the process of extracting the caffeine.
For the experiment I chose a range of mg/250ml for the different brands of tea. I used this range as it was the most suitable for the experiments peaks on the HPLC machine.
The eluent I made for the HPLC was composed of methanol water and then 5ml acetone.

10. Carrying out experiment
For the experiment I used the quantitative analysis method. I did this by checking the retention from the different samples of tea.
I then found out from the retention times in my results table were all roughly in the same time this then proved that there is caffeine in the tea.
I had aimed to isolate caffeine from the mixture of teas I had sourced from Asda. now I had succeeded to extract caffeine from the tea in each of the 12 different samples I needed to collect the key data needed. The different trials of the injection of samples were all compared with retention times and the overall Peak area. From my results I found that the caffeine levels were directly proportional to the concentration of caffeine.

11. Carrying out experiment
After I had injected the samples into the HPLC I obtained my results which are posted below they contain the following data : retention times, peak and peak area. I then used this data to compel a graph.

12. Graph data
The calibration graph created was an excellent fit to the experimental data that I collected, as proven by the high value of the correlation as concentration increased so did the peak absorbance.

13. Objectives and goals review
To design and implement an experiment to determine the caffeine contents in various brands of tea
Be able to use the HPLC machine correctly and efficiently knowing that I can ask if I need help, such as how the machine works or any additional problems
To have learnt how to read graphs and analyse the results using the data I have obtained
Know how to plan an experiment surrounding specialist equipment for the outcome.
Be able to make the solvent for the HPLC machine with the correct percentage of molecules for my mixture.

14. What caffeine does to your brain

16. References
Khalida Khan, Muhammad Naeem , Muhammad Javad Arshad and Muhammad Asif , Extraction and Chromatographic Determination of Caffeine Contents in Commercial Beverages. Journal of Applied Sciences, 6:
Skoog D. A., Holler F. J., and Crouch S. R., Principles of Instrumental Analysis, 6th edition, Harcourt Brace College Publishers, 2007.
Snyder L. R., Kirkland J. J., Introduction to Modern Liquid Chromatography, John Wiley, Toronto, 1979, Pp
Karger B. L., Snyder L. R., Horvath C., An Introduction to Separation Science, John Wiley, Toronto, 1973, Pp