Biomedical evaluation of cortisol, cortisone, and corticosterone along with testosterone and epitestosterone applying micellar electrokinetic chromatography

Solid-Phase Extraction with Packed-Fiber is a Biological Sample Preparation Tool for Neuro-Active Molecule Detection

Neurotransmitters play a major role in shaping everyday life and functions. Accurate analytical methods are needed for detection of neurotransmitters. Packed-fiber solid-phase extraction (PFSPE) has been developed and seems to be an efficient method. This novel method is based on use of an electrospun polymer device, based on nanofibers. This strategy will be helpful for the development of real-time methods and techniques with high sensitivity to detect target neurotransmitters with high efficiency. Here we provide a brief overview of PFSPE and its applications for the determination of neuro-active molecules.

Chemometric evaluation of urinary steroid hormone levels as potential biomarkers of neuroendocrine tumors

Neuroendocrine tumors (NETs) are uncommon tumors which can secrete specific hormone products such as peptides, biogenic amines and hormones. So far, the diagnosis of NETs has been difficult because most NET markers are not specific for a given tumor and none of the NET markers can be used to fulfil the criteria of high specificity and high sensitivity for the screening procedure. However, by combining the measurements of different NET markers, they become highly sensitive and specific diagnostic tests. The aim of the work was to identify whether urinary steroid hormones can be identified as potential new biomarkers of NETs, which could be used as prognostic and clinical course monitoring factors. Thus, a rapid and sensitive reversed-phase high-performance liquid chromatographic method (RP-HPLC) with UV detection has been developed for the determination of cortisol, cortisone, corticosterone, testosterone, epitestosterone and progesterone in human urine. The method has been validated for accuracy, precision, selectivity, linearity, recovery and stability. The limits of detection and quantification were 0.5 and 1 ng mL⁻¹ for each steroid hormone, respectively. Linearity was confirmed within a range of 1–300 ng mL⁻¹ with a correlation coefficient greater than 0.9995 for all analytes. The described method was successfully applied for the quantification of six endogenous steroid levels in human urine. Studies were performed on 20 healthy volunteers and 19 patients with NETs. Next, for better understanding of tumor biology in NETs and for checking whether steroid hormones can be used as potential biomarkers of NETs, a chemometric analysis of urinary steroid hormone levels in both data sets was performed.