Microwave‐accelerated derivatization prior to GC‐MS determination of sex hormones

Insomnia, depression, and Alzheimer's disease are all neurodegenerative diseases and are associated with the levels of steroid hormones. To investigate the internal connection and difference of steroid hormones among these three diseases and distinguish them from the perspective of biomarkers, an easy, quick, and efficient high‐performance liquid chromatography with tandem mass spectrometry method was established and validated to determine six steroid hormones simultaneously in rat serum. The separation was accomplished on a SHIM‐PACK XR‐ODS chromatographic column with 0.1% v/v formic acid and methanol as the mobile phase and the detection was performed with electrospray ionization source in the positive ion mode. Based on the concentrations of steroid hormones, all the groups could be distinguished obviously from each other by using partial least square discriminant analysis. Meanwhile, 11‐deoxycortisol, corticosterone, and cortisol were identified as potential biomarkers and 100% of samples were classified correctly by Bayes’ discriminant function. These biomarkers were further screened by one‐way analysis of variance and cortisol was significantly different among all these groups. Bayes’ discriminant function was also built by cortisol and the classification accuracy was 87.2%. This workflow including determination of steroid hormones and discrimination among three neurological diseases would provide a basis for further clinical studies.

Section: Introductionmentioning

confidence: 99%

The internal link of serum steroid hormones levels in insomnia, depression, and Alzheimer's disease rats: Is there an effective way to distinguish among these three diseases based on potential biomarkers?

Yang

Wang

Zhang

et al. 2019

“…To a lesser extent, MEKC [17,18] and GC [19,20] are also reported. However, a notable disadvantage of GC is the need of derivatization, since estrogens are non-volatile compounds.…”

Section: Of Separation Sciencementioning

confidence: 92%

“…The most common and reliable analytical techniques for estrogen analysis are separation methods, in particular HPLC [13][14][15][16]. To a lesser extent, MEKC [17,18] and GC [19,20] are also reported. However, a notable disadvantage of GC is the need of derivatization, since estrogens are nonvolatile compounds.…”

Section: Introductionmentioning

confidence: 99%

Dispersive liquid–liquid microextraction as an effective preanalytical step for the determination of estradiol in human urine

Kupcová

Reiffová

2017

In this work, a fast and effective dispersive liquid-liquid microextraction was developed for the isolation and preconcentration of free 17 β-estradiol, the main human estrogen, from real human urine samples. To optimize the extraction technique, few important parameters such as type and volume of extraction and dispersive solvents, centrifugation conditions, effect of salt addition, and extraction time were studied. Optimal conditions were obtained when injecting 600 μL mixture of tetrachloromethane as extraction solvent and ethanol as dispersive solvent (1:5, v/v) into 2 mL of urine containing 8% NaCl and following centrifugation at 10 000 rpm, thus reaching enrichment factor 28 and extraction recovery 98% for estradiol. Procedure was evaluated by means of high-performance liquid chromatography with UV detection (λ = 280 nm) using a C-18 column and methanol/water (60:40, v/v) as the mobile phase. The method was linear within the concentration range 1.0-250.0 mg/L (r = 0.9997) and provided a limit of detection of 0.25 mg/L. The proposed method was applied to the determination of free estradiol in real human pregnancy urine.

“…GC is also used to determine steroid hormones, but relatively infrequently, since these compounds are nonvolatile due to their high molecular weight and lack of active groups. Recently, derivatization has been widely used before GC and good LODs and LOQs have been reported compared to the above two methods . LC has been more widely employed for the measurements of steroid hormones in the aquatic environment , and it is usually coupled with MS , UV , or fluorescence detection .…”

Section: Introductionmentioning

confidence: 99%

Enrichment of steroid hormones in water with porous and hydrophobic polymer‐based SPE followed by HPLC–UV determination

Zhang

Tong

et al. 2013

There have been great concerns about the persistence of steroid hormones in surface water. Since the concentrations of these compounds in water samples are usually at a trace level, the efficient enrichment of steroid hormones is vital for further analysis. In this work, a porous and hydrophobic polymer was synthesized and characterized. The composition of solvent used as porogen in the synthetic process was shown to have an effect on the morphology of the polymer, which was successfully used as an SPE sorbent for simultaneously enriching steroid hormones in surface water samples. The recoveries of the steroid hormones on the custom-made polymer ranged from 93.4 to 106.2%, whereas those on commercialized ENVI-18, LC-18, and Oasis HLB ranged from 54.8 to 104.9, 66 to 93.6, and 77.2 to 106%, respectively. Five types of steroid hormones were simultaneously measured using HPLC-UV after they were enriched by the custom-made sorbent. Based on these findings, the SPE-HPLC method was developed. The LODs of this method for estriol, estradiol, estrone, androstenedione, progesterone were 0.07, 0.43, 0.61, 0.27, and 0.42 μg/L, respectively, while precision and reproducibility RSDs were <6.40 and 7.49%, respectively.