title: Exploration of attenuated total reflectance mid-infrared spectroscopy and multivariate calibration to measure immunoglobulin G in human sera.
abstract: Immunoglobulin G (IgG) is crucial for the protection of the host from invasive pathogens. Due to its importance for human health, tools that enable the monitoring of IgG levels are highly desired. Consequently there is a need for methods to determine the IgG concentration that are simple, rapid, and inexpensive. This work explored the potential of attenuated total reflectance (ATR) infrared spectroscopy as a method to determine IgG concentrations in human serum samples. Venous blood samples were collected from adults and children, and from the umbilical cord of newborns. The serum was harvested and tested using ATR infrared spectroscopy. Partial least squares (PLS) regression provided the basis to develop the new analytical methods. Three PLS calibrations were determined: one for the combined set of the venous and umbilical cord serum samples, the second for only the umbilical cord samples, and the third for only the venous samples. The number of PLS factors was chosen by critical evaluation of Monte Carlo-based cross validation results. The predictive performance for each PLS calibration was evaluated using the Pearson correlation coefficient, scatter plot and Bland-Altman plot, and percent deviations for independent prediction sets. The repeatability was evaluated by standard deviation and relative standard deviation. The results showed that ATR infrared spectroscopy is potentially a simple, quick, and inexpensive method to measure IgG concentrations in human serum samples. The results also showed that it is possible to build a united calibration curve for the umbilical cord and the venous samples.
authors.affiliation: Department of Health Management, Atlantic Veterinary College, University of Prince Edward Island, Charlottetown, PEI, Canada C1A 4P3.
authors.forename: Siyuan
authors.initials: S
authors.lastname: Hou
authors.affiliation: Department of Health Management, Atlantic Veterinary College, University of Prince Edward Island, Charlottetown, PEI, Canada C1A 4P3; Institute of Veterinary, Animal and Biomedical Sciences, Massey University, Palmerston North 4442, New Zealand.
authors.forename: Christopher B
authors.initials: CB
authors.lastname: Riley
authors.affiliation: Department of Health Management, Atlantic Veterinary College, University of Prince Edward Island, Charlottetown, PEI, Canada C1A 4P3.
authors.forename: Cynthia A
authors.initials: CA
authors.lastname: Mitchell
authors.affiliation: National Research Council of Canada, Medical Devices Portfolio, Winnipeg, MB, Canada R3B 1Y6.
authors.forename: R Anthony
authors.initials: RA
authors.lastname: Shaw
authors.affiliation: School of Nursing, University of Prince Edward Island, Charlottetown, PEI, Canada C1A 4P3.
authors.forename: Janet
authors.initials: J
authors.lastname: Bryanton
authors.affiliation: Queen Elizabeth Hospital, Charlottetown, PEI, Canada C1A 8T5.
authors.forename: Kathryn
authors.initials: K
authors.lastname: Bigsby
authors.affiliation: Department of Health Management, Atlantic Veterinary College, University of Prince Edward Island, Charlottetown, PEI, Canada C1A 4P3. Electronic address: jmcclure@upei.ca.
authors.forename: J Trenton
authors.initials: JT
authors.lastname: McClure
mesh_terms: D000328:Adult; D002138:Calibration; D002648:Child; D005312:Fetal Blood / Q000737:chemistry*; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood*; D016018:Least-Squares Analysis; D013055:Spectrophotometry, Infrared
chemical_list: D007074:Immunoglobulin G
keywords: Immunoglobulin; Infrared spectroscopy; Partial least squares regression; Umbilical cord; Venous