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How to avoid HPLC missing peaks?

By Mohamed Abouzid|2021-03-22T18:00:32+00:00December 16th, 2020|Lab Diaries, Press release, Science, Science & Technology|0 Comments

You have prepared the samples, and you injected the first injection you are sitting waiting for your beautiful peaks to show up. You waited a lot, but nothing at all. Assuming you were supposed to have a peak after 15 minutes and you did not get it. Just wait 15 minutes more. If nothing appears, so there might be an issue. This simple guide will assist you to overcome the issue of hidden peaks while using HPLC (High-Performance Liquid Chromatography). If you are not able to solve the issue, you can contact the service provider to prevent more damages to your device. You can also inform me if you had similar or new situations and how you were able to solve them. Check if you injected the sample Well, believe, or not this might be the issue. You are using many samples, and you forgot to inject the sample or to turn on the auto-injector, and you run the device. Basically, there will no peaks because there is no sample at all. So just inject your sample, and this will solve the issue. Check if you injected the ‘Correct sample.’ I know this might be silly, but you forgot to mark the vial, and you injected a vial of deionized water instead of your sample. Absolutely, no peaks will be found, so make sure you mark the vials regularly. Improper injection volume When you are working with different devices and constantly changing injection volume you might put it ‘Zero’ or ‘.02 instead of 20’. So, you should check the injection volume through method windows [...]

Vitamin D Receptor and Vitamin D-Related Disorders

We presented a comprehensive review of the evidence on the role of genetic polymorphisms, especially those of vitamin D receptor (VDR), in vitamin D-related disorders including their clinical implications. VDR gene variants seem to influence many biological endpoints, including those related to osteoporosis. BsmI, ApaI, and TaqI are the three adjacent single nucleotide polymorphisms in the VDR gene which have been most frequently studied so far. These polymorphisms are apparently nonfunctional, and one or more functional polymorphism elsewhere in the VDR gene, and linkage disequilibrium may explain the association between VDR genes polymorphisms and common diseases. In different study populations, different alleles of the anonymous restriction fragment length polymorphisms can be found associated with the same endpoint. This effect probably reflects that linkage disequilibrium, between the anonymous marker alleles and the causative alleles in (or very near) the VDR gene, is likely to be different between populations. References Abouzid, Mohamed, Marta Karazniewicz-Lada, and Franciszek Glowka. ‘Genetic Determinants of Vitamin D-Related Disorders; Focus on Vitamin D Receptor’. Current Drug Metabolism 19, no. 12 (2018): 1042–52. https://doi.org/10.2174/1389200219666180723143552.