In recent decades, nanomaterials have been widely used in the field of biomedicine due to their unique physical and chemical properties, and have shown good prospects for in vitro diagnosis, drug delivery, and imaging. With regard to transporting nanoparticles (NPs) to target tissues or organs in the body intravenously or otherwise, blood is the first tissue that NPs come into contact with and is also considered an important gateway for targeted transport. Erythrocytes are the most numerous cells in the blood, but previous studies based on interactions between erythrocytes and NPs mostly focused on the use of erythrocytes as drug carriers for nanomedicine which were chemically bound or physically adsorbed by NPs, so little is known about the effects of nanoparticles on the morphology, structure, function, and circulation time of erythrocytes in the body. Herein, this review focuses on the mechanisms by which nanoparticles affect the structure and function of erythrocyte membranes, involving the hemocompatibility of NPs, the way that NPs interact with erythrocyte membranes, effects of NPs on erythrocyte surface membrane proteins and their structural morphology and the effect of NPs on erythrocyte lifespan and function. The detailed analysis in this review is expected to shed light on the more advanced biocompatibility of nanomaterials and pave the way for the development of new nanodrugs.
The effective cryopreservation of mesenchymal stem cells (MSCs) is indispensable to the operation of basic research and clinical transplantation. The prevalent protocols for MSC cryopreservation utilize dimethyl sulfoxide (DMSO), which is easily permeable and able to protect MSCs from cryo-injuries, as a primary cryoprotectant (CPA). However, its intrinsic toxicity and adverse effects on cell function remain the bottleneck of MSC cryopreservation. In this work, we cryopreserved human umbilical cord mesenchymal stem cells (UCMSCs) using zwitterionic betaine combined with electroporation without any addition of DMSO. Betaine was characterized by excellent compatibility and cryoprotective properties to depress the freezing point of pure water and balance the cellular osmotic stress. Electroporation was introduced to achieve intracellular delivery of betaine, intending to further provide comprehensive cryoprotection on UCMSCs. Compared with DMSO cryopreservation, UCMSCs recovered from the protocol we developed maintained the normal viability and functions and reduced the level of reactive oxygen species (ROS) that are harmful to cell metabolism. Moreover, the in vivo distribution of thawed UCMSCs was consistent with that of fresh cells monitored by a bioluminescence imaging (BLI) system. This work opens a new window of opportunity for DMSO-free MSC cryopreservation using zwitterionic compounds like betaine combined with electroporation.
It remains challenging to detect unknown pathogenic bacteria in diagnostic, clinical and environmental fields. This work describes the approach to the development of a sensitive, broad-range genosensing assay targeting the conserved 16S rDNA region existing in most bacteria, by monitoring the aggregation level of gold nanorods (GNRs)-based nanoprobes through their localized surface plasmon resonance (LSPR) property. In the quantitative detection of artificial sequence, the limit of detection (LOD) of such a bioassay is demonstrated to reach the 5 pM level. This pair of universal GNRs-based nanoprobes can further identify at least 6 species of bacteria that were most prevalent in platelet concentrates (PCs) and have no cross-reaction with other pathogens. Moreover, it also exhibits higher sensitivity than other broad-range methods in analysing Serratia marcescens-spiked PCs. Therefore, the presented strategy not only provides a novel and effective DNA analysis method to detect multiple bacterial contaminations in PCs, but also opens up possibilities for its future use of detecting unknown bacteria in other systems, such as food and water, even at ultralow levels.