Indirect Photometric and Fluorometric Detection in High-Performance Liquid Chromatography: A Tutorial Review

Miniaturized capillary ion chromatograph with UV light‐emitting diode based indirect absorbance detection for anion analysis in potable and environmental waters

“…The LOD for each analyte anion was calculated using S/N = 3, and the LOQ was calculated using S/N = 10 . The sub‐mg/L LODs obtained are comparable to those reported by others using standard instrumentation and indirect UV based methods , which given the capillary format applied herein, is also highly encouraging. The analytical performance demonstrated by the system, as listed within Table , confirms the suitability of the miniaturized IC platform for the analysis of a range of natural and potable waters.…”

Direct estimation of ethanol as a negative peak from alcoholic beverages and fermentation broths by reversed phase-HPLC

“…Reports suggest that the sensitivity of indirect photometric estimation depends entirely on the added UAC, which in turn relies on charge, ion pairing mechanisms, pH, protolysis and other buffering agents in the mobile phase. 2,6,11 However, the present work essentially detects the negative peak of ethanol directly thus enabling linearity from 0.1 to 100% (v/v). During optimization, injection volumes (>5 mL) for ethanol concentrations above 25% resulted in either a deformed system peak or merged system and sample peaks.…”

“…Indirect ultraviolet (UV) determination of analytes of biological samples, solvents and impurities in pharmaceutical drugs using Reversed Phase (RP)-HPLC is a relatively older technique. [1][2][3][4] The technique relies on detecting compounds with low UV absorbing properties and the detection is facilitated by adding a minimal quantity of a high UV absorbing compound (UAC) to the mobile phase which equilibrates itself throughout the column and sets a high UV absorbing background. 4 When a low UV absorbing sample is injected, a positive or a negative peak at the retention time (RT) corresponding to the sample emerges.…”