2. The type of column used is listed, this column contains the stationary phase and the mobile phase is pumped through the column under pressure.
The dimensions of the column are listed as this will determine how much stationary phase is inside the column. As well as the size of the stationary phase particles, the amount in the column can determine how quickly the sample will pass through i.e. if there are a small number of small particles …show more content…
By analysing the area of each peak using HPLC you can work out the drug concentration in the sample using the area under each peak. (Std x (sample/standard)). This answer should give the drug concentration per x mls (however much sample was used). You can then compare this with the stated amount of drug in the same amount of millilitres. A percentage can then be calculated to see how near to 100% the drug in the sample is. It can then be decided whether the drug is within the limits to pass or not.
5. An advantage for HPLC is that it is a very precise technique and it will give qualitative and quantitative results. TLC, on the other hand, is very unreliable and will only give qualitative results. HPLC has a significant amount of solvent waste as it requires large volumes of the mobile phase whereas TLC only needs a small amount of the mobile phase. TLC is a quick, cheap and easy technique and one doesn't need a high level of skill to operate it compared to HPLC where one needs to be highly trained to operate the apparatus and it is quite expensive but quicker. For most analyses of HPLC, a UV detection is used and so the sample has to have a chromophore. With TLC, different types of detection can be used, for example mass spectrometry or UV. HPLC is a versatile technique and it is easily automated but if there are excipients in the formulation then this can cause peak overlaps to occur on the chromatogram, therefore these excipients must be removed before