Embryonic stem cell (ESC) markers are molecules specifically expressed in ES cells. Understanding of the functions of these markers is critical for characterization and elucidation for the mechanism of ESC pluripotent maintenance and self-renewal, therefore helping to accelerate the clinical application of ES cells. Unfortunately, different cell types can share single or sometimes multiple markers; thus the main obstacle in the clinical application of ESC is to purify ES cells from other types of cells, especially tumor cells. Currently, the marker-based flow cytometry (FCM) technique and magnetic cell sorting (MACS) are the most effective cell isolating methods, and a detailed maker list will help to initially identify, as well as isolate ESCs using these methods. In the current review, we discuss a wide range of cell surface and generic molecular markers that are indicative of the undifferentiated ESCs. Other types of molecules, such as lectins and peptides, which bind to ESC via affinity and specificity, are also summarized. In addition, we review several markers that overlap with tumor stem cells (TSCs), which suggest that uncertainty still exists regarding the benefits of using these markers alone or in various combinations when identifying and isolating cells.

High quality water-soluble photoluminescent (PL) microspheres consisting of CdSe/ZnS quantum dots (QDs) and amphiphilic oligomers (polymaleic acid n-hexadecanol ester) were prepared by a versatile phase transfer method in an emulsion system. Controlled synthesis of different sizes of PL microspheres can be conducted by simply changing the initial oligomer concentration and/or the water/chloroform volume ratio. When the oligomer/QDs molar ratio exceeded 200 : 1, only oligomer-coated monodisperse CdSe/ZnS QDs without any aggregation were obtained. If the molar ratio ranged from 20 : 1 to 120 : 1, size-tunable PL microspheres could be obtained with a size range from 151 to 50 nm. Both of them exhibited high stability in aqueous solution under a wide range of pH, different salt concentrations, and thermal treatment at 100 °C. FTIR spectroscopy, transmission electron microscopy, dynamic light scattering, and fluorescence microscopy were used to characterize the PL microspheres and oligomer-coated monodisperse QDs. It is demonstrated that the stability of PL microspheres indeed depended on their dimensions. Larger PL microspheres could provide more hydrophobic protection for their interior QDs than smaller PL microspheres. A biosensor system (lateral flow immunoassay system, LFIA) for the detection of human chorionic gonadotrophin (HCG) antigen was developed by using CdSe/ZnS PL microspheres as fluorescence labels and a nitrocellulose filter membrane for lateral flow. The result showed that the PL microspheres were excellent fluorescence labels to detect HCG antigen in this LFIA system. The sensitivity of HCG antigen detection can reach 0.5 IU L⁻¹, which is almost 20 times higher than traditional LFIAs using tinctorial labels.

Cancer is one of the leading causes of death globally. A variety of phenolic compounds display preventative and therapeutic effects against cancers. Green teas are rich in phenolics. Catechins are the most dominant phenolic component in green teas. Studies have shown that catechins have anticancer activity in various cancer models. The anticancer activity of catechins, however, may be compromised due to their low oral bioavailability. Nanodelivery emerges as a promising way to improve the oral bioavailability and anticancer activity of catechins. Research in this area has been actively conducted in recent decades. This review provides the molecular mechanisms of the anticancer effects of catechins, the factors that limit the oral bioavailability of catechins, and the latest advances of delivering catechins using nanodelivery systems through different routes to enhance their anticancer activity.