Characterization of two excipient interaction degradation products in oseltamivir phosphate powder for oral suspension by MS and NMR.

Oseltamivir phosphate is widely used to treat and prevent influenza, and is available in the form of capsules, powder for oral suspension, pediatric solutions, and granules. Because of the amino group, oseltamivir is easy to react with the excipients of the formulation to generate drug-excipient interaction impurities. In this research, two degradation products in a commercial oseltamivir phosphate powder for oral suspension due to interaction between API and citrate were investigated.

N-Nitrosodimethylamine formation in metformin hydrochloride sustained-release tablets: Effects of metformin and hypromellose used in drug product formulation.

In recent years, nitrosamines have been discovered in some types of drug products that becomes a current regulatory hotspot, and have attracted a lot attention from both regulatory authorities and industry. This manuscript provided an industry perspective on the nitrosamines research. A liquid chromatography coupled with tandem mass spectrometry（LC-MS/MS）method was developed and applied for the quantification of N-nitrosodimethylamine (NDMA) in metformin hydrochloride sustained-release tablets (MET).

"Ghost peaks" of olmesartan medoxomil: Two solution degradation products of olmesartan medoxomil via oxidation mediated by metal ions.

Two unknown solution degradants were found during the dissolution testing in 0.1-M HCl for olmesartan medoxomil (OLM) tablets. The structure of the degradants was identified and characterized by liquid chromatography-ultraviolet (LC-UV), liquid chromatography with tandem mass spectrometry (LC-MS/MS), and nuclear magnetic resonance (NMR) and demonstrated to be cyclization of tetrazole and benzene in the olmesartan (OL) and OLM structures.

Azithromycin "ghost peak": A solution degradation product of azithromycin via leaching from borosilicate glass volumetric flasks and vials.

An interference peak was found while detecting related substances of azithromycin. It is impressive that the degradation peak occurred at about 70 min in the next injection of the test solution (4 mg/mL or higher). Once the degradation peak was observed, it would keep growing.

CEMTDD: The database for elucidating the relationships among herbs, compounds, targets and related diseases for Chinese ethnic minority traditional drugs.

China has different ethnic minorities that establish their own medical systems and practice experience for thousand years, thereafter named Chinese Ethnic Minority Traditional Drugs (CEMTDs) (http://www.cemtdd.com/index.

Protective effects of Zhuyeqing liquor on the immune function of normal and immunosuppressed mice in vivo.

Background: Zhuyeqing Liquor (ZYQL), a well-known Chinese traditional health liquor, has various biological properties, including anti-oxidant, anti-inflammatory, immunoenhancement and cardiovascular protective effects.

Methods: The protective effects of Zhuyeqing Liquor (ZYQL) on the immune function was investigated in vivo in normal healthy mice and immunosuppressed mice treated with Cyclophosphamide (Cy, 100 mg/kg) by intraperitoneal injection on days 4, 8 and 12. ZYQL (100, 200 and 400 mg/kg) was administered via gavage daily for 14 days.