Determination of hydroxyproline in rat urine by high-performance liquid chromatography with electrogenerated chemiluminescence detection using tris(2,2′-bipyridyl) ruthenium(II)

Bioanalytical Method for the Determination of Hydroxyproline in Mouse Kidney by High-Performance Liquid Chromatography with Tandem Mass Spectrometric Detection

An analytical method was developed and validated for the measurement of hydroxyproline (Hyp) levels in mouse kidney by high-performance liquid chromatography with tandem mass spectrometric detection (LC/MS/MS) using an analytical column specially designed for the LC/MS/MS analysis for intact amino acids. Tissue hydrolyzed with hydrochloric acid could be directly injected into the LC/MS/MS, as well as separated and detected using the deuterium labelled Hyp as an internal standard. The calibration curve showed good linearity from 5 to 500 nmol/mg of tissue; the precision and accuracy, including within- and between-run, were less than 6% and within 100 ± 6%, respectively.

High-performance liquid chromatography–post-column chemiluminescence determination of aminopolycarboxylic acids at low concentration levels using tris(2,2′-bipyridyl)ruthenium(III)

A simple, selective and sensitive method for the determination of aminopolycarboxylic acids [diethylenetriaminepentaacetic acid (DTPA), S,S-ethylenediamine N,N'-disuccinic acid (EDDS), ethylenediaminetetraacetate (EDTA) and nitrilotriacetate (NTA)] has been developed using high-performance liquid chromatography with chemiluminescence detection. The aminopolycarboxylic acids were separated on a C18 reversed-phase column with an aqueous sulfuric acid mobile phase at a pH lower than 1.5. The eluate was mixed with tris(2,2'-bipyridyl)ruthenium(III), which was on-line generated by photooxidation of the ruthenium(II) complex in the presence of peroxydisulfate, and the generated chemiluminescence was detected. Calibration graphs, based on standard solutions, were linear over the range 8x10(-9) to 4x10(-5) M. The detection limits at a signal-to-noise ratio of 3 ranged from 9x10(-10) to 8x10(-8) M. The relative standard deviations of intra- and inter-day precision were below 1.3% and 2.1%, respectively. This HPLC system was successfully applied to the determination of aminopolycarboxylic acids in three different types of water samples. The low pH of the mobile phase limits interference from metal ions in natural waters. When such interference occurs, a cation-exchange column can be used to suppress it. The lowest amounts measurable were: 75 pg for NTA, 0.7 ng for EDDS, 0.8 ng for DTPA and 12ng for EDTA. The method was also applied for the EDTA assay in canned foods.

Highly sensitive and simple method for measurement of pipecolic acid using reverse-phase ion-pair high performance liquid chromatography with tris(2,2′-bipyridine)ruthenium(III) chemiluminescence detection

A new, highly sensitive chemiluminescence method for measurement of pipecolic acid in various substances such as human serum, cow's milk, beer, and apple juice has been developed. The method is based on reverse-phase ion-pair high performance liquid chromatographic separation and subsequent tris(2,2'-bipyridine)ruthenium(III) chemiluminescence detection. It was confirmed that imino acids show strong chemiluminescence upon mixing with tris(2,2'-bipyridine)ruthenium(III). A calibration graph, based on a standard pipecolic acid solution, was linear over the range 5.0x10(-9)M to 2.0x10(-5)M and the detection limit was 24fmol (signal-to-noise ratio=3). This highly sensitive and selective determination method can be applied to selected samples without purification or pre-concentration procedures. Compared to the previous HPLC methods, the proposed method is easier, more sensitive, and time-saving.

Tris(2,2'-bipyridyl)ruthenium(II) chemiluminescence

This paper critically reviews analytical applications of the chemiluminescence from tris(2,2'-bipyridyl)ruthenium(II) and related compounds published in the open literature between mid-1998 and October 2005. Following the introduction, which summarises the reaction chemistry and reagent generation, the review divides into three major sections that focus on: (i) the techniques that utilise this type of detection chemistry, (ii) the range of analytes that can be determined, and (iii) analogues and derivatives of tris(2,2'-bipyridyl)ruthenium(II).