high performance liquid chromatography what is it how does it work and why is it useful high performance liquid chromatography or hplc is the single biggest chromatography technique to most Laboratories worldwide if you have watched any of my videos on column chromatography the main idea is the same that is to say hplc has four aspects of it in common with other chromatography techniques one it separates mixtures of substances into their constituent components to it has a stationary face and a mobile face three the mobile phase flows through the stationary phase and carries the sample with it for different components in the sample will travel at three different rates due to how they interact with the stationary phase thereby separating them however hplc is a highly improved form of column chromatography a pump forces to solvent through the column under pressures of up to 400 atmospheres the stationary phase is usually made of solid particles such as silica or polymers this pressure makes the technique much faster than normal types of column chromatography which in turn allows for much smaller particles for the column packing material which in turn leads to more particle surface area for interaction between the mobile and stationary phase all that is to say that ultimately this leads to much better separation hplc is in addition highly automated and extremely sensitive let us look at how this device operates in Greater detail so first we have a mobile face which is connected to a delivery pump which speeds up the overall process this is what we talked about earlier second the liquid sample is added to the setup usually through a different tube then the sample gets carried with the mobile phase through the column and the stationary phase and the interaction happens thereby separating them so at this point the sample gets separated into its constituent parts then a detector converts the amount of each component into an electrical signal if you feel like this was a clear explanation please show some quick Love by liking the video the two most common types of hplc are normal face hplc and reversed phase hplc normal phase hplc is the less common of the two and uses a non-polar solvent in addition it is filled with tiny silica particles which are polar this polar silica particles interact more with polar compounds making compounds stick longer the more polar they are this results in polar compounds moving slower through the column while non-polar compounds move more quickly Through It reversed phase hplc is the more common and works in the exact same manner except that it is sort of the opposite here the silica particles have been modified in order to make them non-polar and a polar solvent is used this causes the exact opposite effect making the more nonpolar compounds move slower and the more polar compounds move faster if you wish to learn more about some other technique of chromatography check SSR that I have already done a video on it which you in that case will find in this chromatography playlist so please check that out if it could help you and send this video to a friend who is struggling with all of this as well so then you can help me help them good wipes all around until next time