What Is Caffeine?

Caffeine is a drug that is used to improve mental alertness by stimulating the central nervous system [1]. It is an ingredient found in a various amount of products sold on the market today, such as coffee, tea, chocolate, soft drinks, and energy drinks. Caffeine can be taken by mouth or intravenously (by IV) to help alleviate breathing problems in infants and can even be used in combination with some pain killers to treat migraines after epidural anesthesia. Moreover, it can be helpful in preventing Parkinson’s disease, gallstone disease, and improving weight loss [2]. The chemical structure of caffeine is shown in figure one. On the other hand, consuming more than 300mg-400mg of caffeine per day can have negative effects on the body and can
A diagram of the inner workings of the instrument can be seen in figure one below. First, a sample is injected into the injection loop with the use of a syringe. After the injection is complete, the lever of the injection loop is pulled down to create a high pressure pump that pushes the sample into the mobile phase of the instrument. This mobile phase, which for this experiment will consist of water and methanol, transports the samples toward the packed column where it will leave the mobile phase and enter the stationary phase. In this stationary phase, the sample is fixed in place for the amount of time it takes for the sample to elute back to the mobile phase. This stage identifies and quantifies the components of the sample based on their affinity for the stationary phase. After leaving the stationary phase, the sample moves through a photodiode array absorbance detector where it is analyzed for peak areas. The detector then sends the signal to the software on the computer which converts it into a chromatogram. This chromatograph is used to pinpoint the peak areas of the caffeine in each serial dilution solution. This data will be used to create a calibration curve based on Beer’s Law, which will make it possible for the amount of caffeine present in the unknown sample of cola to be
The dual use of these techniques creates a non-polar surface for the column so that the molecules will be less soluble in the solvent. In other words, this partition allows the molecule to spend more time being attracted to the silica rather than the solvents in which the molecules are highly soluble in. To do this, the silica is modified with long hydrocarbon chains added to its surface to create a strong attraction between the polar solvents and molecules passing through the column [5]. Therefore, the efficiency of the packed column will increase as the size of the molecule decreases due to the high pressure system. This will induce shaper peaks that will be easier for the instrument to measure and will result in an accurate peak area. The use of the reversed phase technique with less polar solvents that yield higher eluent strength will also eliminate peak tailing. Similarly, the solubility of the gas will decrease in the high pressure system and will result in more samples processed and analyzed by the instrument rather than dissolved and lost in the stationary phase with the polar solvents