Quantitation of endogenous GnRH by validated nano-HPLC-HRMS method: a pilot study on ewe plasma.

Gonadotropin-releasing hormone isoform I (GnRH), a neuro-deca-peptide, plays a fundamental role in development and maintenance of the reproductive system in vertebrates. The anomalous release of GnRH is observed in reproductive disorder such as hypogonadotropic hypogonadism, polycystic ovary syndrome (PCOS), or following prenatal exposure to elevated androgen levels. Quantitation of GnRH plasma levels could help to diagnose and better understand these pathologies.

Characterization of alkaloids in bark extracts of Geissospermum vellosii by HPLC-UV-diode array-multistage high-resolution mass spectrometry.

A number of analytical studies, started in the sixties of the last century, concerning the stem bark of Geissospermum vellosii, have documented the presence of a number of indole alkaloids whose molecular identity was defined by NMR technique. The potential bioactivity of these compounds has inspired more recent analogous studies either devoted to structural elucidation of new alkaloid molecules or to the investigation of the role of some of them in cancer therapy. Anyway, a complete fingerprinting of the bark content is still lacking.

Development and application of high resolution mass spectrometry analytical method to study and identify the photoinduced transformation products of environmental pollutants.

Terpenes are among the major causes of pleasant or unpleasant odors close to active or inactive landfills. We studied R-limonene and p-cymene environmental degradation products using the heterogeneous photocatalysis mediated by titanium dioxide to explore the odor pollution. The aim of the study was the development of mass spectrometry based methods both hyphenated with GC and HPLC to identify and characterize transformation products (TPs) derived from photodegradation of R-limonene and p-cymene.

Quali-Quantitative Characterization of Volatile and Non-Volatile Compounds in (Aubl.) Marchand Resin by GC-MS Validated Method, GC-FID and HPLC-HRMS.

(Aubl.) Marchand (PH) trees are endemic to the tropical region of South America, mostly Brazil. Antibacterial, antinociceptive, anti-inflammatory, anxiolytic, antidepressant and anti-hyperlipidemic/anti-hypercholesterolemic effects were reported for its resinous exudate resin (PHR).

HPLC-HRMS Global Metabolomics Approach for the Diagnosis of "Olive Quick Decline Syndrome" Markers in Olive Trees Leaves.

Olive quick decline syndrome (OQDS) is a multifactorial disease affecting olive plants. The onset of this economically devastating disease has been associated with a Gram-negative plant pathogen called (Xf). Liquid chromatography separation coupled to high-resolution mass spectrometry detection is one the most widely applied technologies in metabolomics, as it provides a blend of rapid, sensitive, and selective qualitative and quantitative analyses with the ability to identify metabolites.