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Experiment 1Lab Report

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Experiment 1Lab Report
Experiment 1 Lab Report

Title:
Determination of caffeine content in tea bag sample by UV spectroscopic method

Higher diploma in Pharmaceutical Science-Year 1
AS114202-1TM

Fundamental Analytical Chemistry
ASD3008

Lab Group 6:
Ng Chung Hin 130439161
Wong Tin Yau Tony 130252529
Ng Wai Kin 130031247
Tam Chun Kit 130191034
Mau Kwan Yiu 130395762

Date of Experiment: 7/3/2014
Content

Introduction
Objectives
Methodology
Results
Discussion
Conclusions
References

Introduction
Caffeine is one of the ingredient that contain in tea. There are many types of tea and they contain different content of caffeine. To determine the caffeine content in tea bag, we can use UV spectroscopic method with single-beam UV or double-beam UV.
Spectrophotometry is the quantitative measurement of the reflection or transmission properties of a material as a function of wavelength. It is more specific than the general term electromagnetic spectroscopy in that spectrophotometry deals with visible light, near-ultraviolet, and near-infrared, but does not cover time-resolved spectroscopic techniques. Spectrophotometry involves the use of a spectrophotometer. A spectrophotometer is a photometer that can measure intensity as a function of the light source wavelength. Important features of spectrophotometers are spectral bandwidth and linear range of absorption or reflectance measurement.
Caffeine is a chemical found in coffee, tea, cola, mate, and other products. Caffeine is most commonly used to improve mental alertness, but it has many other uses. Caffeine is used by mouth or rectally in combination with painkillers (such as aspirin and acetaminophen) and a chemical called ergotamine for treating migraine-headaches. It is also used with painkillers for simple headaches and preventing and treating headaches after epidural anesthesia. Caffeine works by stimulating the central nervous system (CNS), heart, muscles, and the centers that control blood pressure. Caffeine can


References: Larry G. Hargis, (1988). Analytical Chemistry Principle and Techniques. 1st ed. USA: Prentice-Hall, INC. Ronald C. Denney and Roy Sinclair. Visible and Ultraviolet Spectroscopy. London: ACOL, Thames Polytechnic, 1993. Print.  McMahon Gillian. Analytical Instrumentation - A Guide to Laboratory, Portable and Miniaturized Instruments. Ireland: John Wiley & Sons, LTD, 2007. Print.
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