Determining the Concentration of Procalcitonin Using a Magnetic Particles-based Chemiluminescence Assay for the Clinical Diagnosis of Sepsis

Abstract

Our objective is to develop an assay based on magnetic particles (MPs) to determine the concentration of procalcitonin (PCT) using a chemiluminescence immunoassay (CLIA). Fluorescein isothiocyanate (FITC) and N-(aminobutyl)-N-(ethylisoluminol) (ABEI) were used to label two different anti-procalcitonin (PCT) monoclonal antibodies. The labeled antibodies, the PCT antigen, and the anti-FITC antibody-coated MPs formed a double-sandwiched immunocomplex. The measured relative light units (RLUs) of ABEI in the substrate solution were directly proportional to the amount of PCT present in the samples. The proposed method was linear to 600 ng/mL with a detection limit of 0.03 ng/mL. The coefficient of variation (CV) was <5% and <6% for the intra-and inter-assay precision, respectively. The average recoveries were between 95 and 107%. The linearity-dilution effect gave a linear correlation coefficient of 0.9912. This proposed assay provided an alternative method to quantitatively measure PCT in serum for the diagnosis of sepsis.

Establishment of reference intervals for maternal blood and umbilical cord blood procalcitonin in healthy Chinese women in late pregnancy

“…The other antibody was labeled with a fluorescent substance and used as a tracer. During the assessment, two specific antibodies and the PCT antigen formed a double antibody sandwich complex, and the PCT level was determined by analyzing the fluorescence signal intensity …”

Magnetic Bead-Based Electrochemical Immunoassays On-Drop and On-Chip for Procalcitonin Determination: Disposable Tools for Clinical Sepsis Diagnosis

“…However, the potential of immunosensors based on magnetic beads has not been widely explored for PCT determination, which is apparent in the low number of publications (Table 4). In comparison with those works, our SPE-C approach offers enough sensitivity (similar to our previous work [40]) to perform reliable PCT detection, but with a significant reduction in the analysis time and sample volumes [16,17,35,36]. Moreover, the easy automation of the electrochemical transduction and the improved sensitivity [40] bring our new approach (on-chip EMC-Au) closer to the POC concept.…”

“…Several methods have been reported for PCT determination, mainly based in the selective recognition provided by immunological interactions. These methodologies include immunoturbidimetric assays [9], chemiluminescent immunoassays [10][11][12][13][14][15][16], immunochromatographic assays [17][18][19][20][21][22], surface plasmon resonance biosensors [23][24][25], fluorescence immunosensors [26][27][28][29][30][31][32], ellipsometry immunosensors [33], colorimetric immunoassays [34][35][36], and electrochemical immunoassays [37][38][39][40][41][42][43][44][45][46][47][48][49][50][51][52][53][54][55][56]. Even differen...…”

“…The use of magnetic beads has been largely exploited in recent years due to their well-known properties such as improved assay kinetics and easy manipulation, while they are perfectly coupled to electrochemical detection [58]. However, magneto-immunosensors [16,17,35,36] in general, and particularly those using electrochemical detection [40], have not been widely explored for PCT determination.…”

Polymer-Based Micromotor Fluorescence Immunoassay forOn-the-MoveSensitive Procalcitonin Determination in Very Low Birth Weight Infants’ Plasma

“…Taking into account the importance that PCT has acquired as a biomarker of sepsis, this result is very valuable and promising because, for the first time, the ability of micromotor technology to measure very low PCT concentrations in neonatal clinical samples with sepsis suspicion, which are hardly available, has been evaluated. Only 25 Nevertheless, this work has not been tested in clinical samples either. Moreover, it can be said that our approach elegantly combined short analysis times using low volumes of clinical samples, which proved to be very suitable for diagnostic purposes using this very unique samples.…”