On Chip Liquid Chromatography- A Review

Liquid chromatography is applied in biology, medicine, the environment, forensics, and other fields, making it an essential separation method. Liquid chromatography is a technique used to separate and analyze components of a liquid mixture based on their interactions with a stationary phase and a mobile liquid phase. The aim of the present review is to explore different On-Chip liquid chromatographic methods for the analysis of drugs. Liquid chromatography miniaturization has advanced significantly in order to provide reduced sample and minimal eluent consumption as well as simple electrospray-mass accessibility. Because microfluidics requires small sample volumes, quick analysis, and simple integration, it has garnered a lot of attention lately in the shrinking of HPLC systems. For polymer materials, grafting procedures, sol-gel processes, and traditional silane chemistry are frequently employed. The ease of preparation and the comparatively low pressures needed for driving are the main benefits of the open channel configuration. The on-chip microvalve, packedparticle analytical column, enrichment column, and nanospray emitter are the different types of columns used for on-chip liquid chromatography. The utilization of pillar array columns, packed-particle, open-tubular, and monolithic structures have been increased recently in the analysis of drugs with lowest concentration. These techniques have been used in proteomics and drug and small molecule analysis in a variety of biological samples. This technique has been successfully applied for proteome studies and analysis of small molecules like 7- aminoflunitrazepam in human urine, 8-isoprostaglandin F2α in human urine, hepcidin (a peptide marker of clinical disorders related to iron metabolism) in human plasma, pharmaceutical drugs with a wide range of hydrophilicities, fluoxetine and norfluoxetine in rat serum, illicit drugs and metabolites in human hair, and 7-ethyl-10-hydroxycamptothecin (SN38) in mouse plasma.