The most widely used ionization techniques in liquid chromatography-mass spectrometry (LC-MS) are electrospray ionization (ESI), atmospheric pressure chemical ionization (APCI) and atmospheric pressure photoionization (APPI). All three provide user friendly coupling of LC to MS. Achieving optimal LC-MS conditions is not always easy, however, owing to the complexity of ionization processes and t...

A combination of TLC-bioautography, MALDI-TOF-MS, and LC-MS/MS methods was used to identify flavonoids with anti-α-amylase activity in extracts L. pratensis (herb), polyphillus (fruits), T. lanceolata R. Br. S. japonica (buds). After TLC-autobiography assay, substances anti-amylase were identified by MALDI-TOF-MS followed confirmation the result LC-MS/MS. Results study revealed that apigenin, l...

BACKGROUND Posaconazole is a novel antifungal drug for oral application intended especially for therapy of invasive mycoses. Due to variable gastrointestinal absorption, adverse side effects, and suspected drug-drug interactions, therapeutic drug monitoring (TDM) of posaconazole is recommended. METHOD A fast ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method ...

To the Editor: Therapeutic drug monitoring of immunosuppressive agents by liquid chromatography (LC) coupled with mass spectrometry (MS) can provide highly selective and sensitive quantification from biological fluids. Interlaboratory performance for cyclosporine, tacrolimus, and sirolimus, as assessed by LC/MS, in proficiency testing (PT) programs [e.g., College of American Pathologists (CAP) ...

Cleistocactus winteri is a succulent plant of the Cactaceae family, commonly known as the golden rat tail. Many members of the Cactaceae family are the focus of chemical and biological studies as they contain bioactive compounds, well known for their health-related properties. We aimed to investigate Cleistocactus winteri stems both phytochemically and biologicallyfor the firs...

Smoking marijuana during pregnancy can cause health problems in the neonate. The detection of exposure can guide treatment to meet the short- and long-term medical and social needs. Umbilical cord tissue was analyzed for 11-nor-delta-9-carboxy-tetrahydrocannabinol (THC-COOH) by gas chromatography-mass spectrometry (GC-MS), and compared with ultra-sensitive enzyme-linked immunosorbent assay (ELI...

We demonstrated the complementary use of inductively coupled plasma-mass spectrometry (ICP-MS) and electrospray ionization quadrupole time-of-flight mass spectrometry (ESI-Q-TOF-MS) for the analysis of Se-containing compounds, such as selenate, selenomethionine (SeMet), and trimethylselenonium ion (TMSe), found in biological samples. The sensitivity of ESI-Q-TOF-MS for Se-containing compounds w...

In the present study, comprehensive stress testing of amlodipine (AM) was carried out according to International Conference on Harmonization (ICH) Q1A(R2) guideline. AM was subjected to acidic, neutral and alkaline hydrolysis, oxidation, photolysis and thermal stress conditions. The drug showed instability in acidic and alkaline conditions, while it remained stable to neutral, oxidative, light ...

BACKGROUND Novel mass spectrometric techniques such as atmospheric pressure ionization and tandem mass spectrometry have substantially extended the spectrum of clinical chemistry methods during the past decade. In particular, liquid chromatography tandem-mass spectrometry (LC-MS/MS) has become a standard tool in research laboratories as well as in many clinical laboratories. Although LC-MS/MS h...