Experimental methods in chemical engineering: High performance liquid chromatography—HPLC

Abstract

High performance liquid chromatography (HPLC) identifies compounds in a sample and quantifies their concentration. The instrument consists of an injector that introduces a μL sample to a mobile phase that carries the analytes across a column filled with an adsorbing substance. The analytes adsorb and desorb at different rates as they flow down the column and are thereby separated. Detectors record a signal proportional to the concentration of the analyte in the mobile phase. Laboratories apply modern HPLC systems for research and development, quality control, safety, and validation. Academia and industry resort to HPLC to purify, identify, and characterize a wide variety of molecules at all stages of a process. Developing an HPLC analytical method is a long and laborious process requiring standards, calibration curves, derivatization, and multiple tests to identify an appropriate column, stationary phase, flow rate, temperature, and mobile phase. Optimal operating conditions maintain a good resolution (high signal‐to‐noise ratio and low peak overlap) while minimizing analysis time. Web of Science Core Collection indexed 8900 articles in 2019, which is relatively few compared to x‐ray and scanning electron microscopy. However, it is such an ubiquitous technique and we estimate that the number of articles that report it in the experimental section is an order of magnitude higher. The bibliometric analysis of the keywords identified four research clusters: phenolics and flavonoids, extraction and pharmacokinetics, in vitro and oxidative stress, and optimization. Here, we detail a walkthrough for the basic steps required to develop a chromatographic method.

Phosphate Enrichment of Niobium-Based Catalytic Surfaces in Relation to Reactions of Carbohydrate Biomass Conversion: The Case Studies of Inulin Hydrolysis and Fructose Dehydration

“…and in water:isopropanol mixture (80:20 v/v), a polar/protic solvent, for the effective acidity (E.A.). Analyses were performed in a modified liquid-chromatographic line operating in a recirculating mode [19,46,69,70].…”

Physicochemical properties of tiger nut (Cyperus esculentus L) polysaccharides and their interaction with proteins in beverages

“…The molecular mass of TNP-N and TNP-A were determined and analyzed through LC-10Avp HPLC using a 0.2 M NaCl solution and filtered through a 0.22 μm membrane ( Schieppati, Patience, Campisi & Patience, 2021 ).…”

Interface properties of hydroxyapatite in ternary composites cathodes for electromethanogenesis

“…All the details on the operative and interpretative procedures can be found elsewhere. 53,54 Thermo-desorption analyses were carried out using ammonia (NH 3 -TPD) or sulphur dioxide (SO 2 -TPD), as basic and acid probe, respectively, by operating in a homemade adsorption/ desorption line. The line was equipped with a set of mass flow controllers (Bronkhorst, Hi-Tec and Brooks Instruments), a tubular vertical electric oven (Eurotherm controller-programmer type 818), a quartz tubular sample-holder with a porous septum (5 mm i.d.)…”