[Application progress of on-line sample preparation techniques coupled with liquid chromatography-mass spectrometry system in the detection of food hazards].

Food safety has received increased attention, and food detection is of great significance. The food matrix is complex, and diverse food hazards have been identified. Thus, the detection methods and sample preparation techniques for food matrices must be continuously optimized and updated.

Determination of Deoxynivalenol and Its Derivative in Corn Flour and Wheat Flour Using Automated On-line Solid-Phase Extraction Combined with LC-MS/MS.

An automated on-line solid-phase extraction (SPE) combined with LC-MS/MS method was developed for determination of deoxynivalenol (DON), 3-acetyl-DON and 15-acetyl-DON in corn flour and wheat flour samples. The extraction solvent of the samples was injected into the automated on-line SPE system to remove matrix interference. After washing step, the targets were eluted from the SPE cartridge into liquid chromatography (LC) column.

[Determination of ten alkaloids in cosmetics by high performance liquid chromatography-tandem mass spectrometry].

A high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method was established for the determination of ten alkaloids in cosmetics. Extraction conditions, purification methods and instrumental parameters were optimized. The samples were ultrasonically extracted with 80% (v/v) methanol aqueous solution.

Natural zwitterionic l-Carnitine as efficient cryoprotectant for solvent-free cell cryopreservation.

Organic solvents, such as dimethyl sulfoxide (DMSO) and glycerol, have been commonly used as cryoprotectants (CPAs) in cell cryopreservation. However, their cytotoxicity and need of complex freezing protocols have impeded their applications especially in clinical cell therapy and regenerative medicine. Trehalose has been explored as a natural CPA to cryopreserve cells, but its poor cell permeability frequently results in low cryopreservation efficacy.

Natural zwitterionic betaine enables cells to survive ultrarapid cryopreservation.

Cryoprotectants (CPAs) play a critical role in cryopreservation because they can resist the cell damage caused by the freezing process. Current state-of-the-art CPAs are mainly based on an organic solvent dimethyl sulfoxide (DMSO), and several DMSO-cryopreserved cell products have been brought to market. However, the intrinsic toxicity and complex freezing protocol of DMSO still remain as the bottleneck of the wide use for clinical applications.