Jun Liang

Spinal cord injury (SCI) repair lacks clinically validated restorative therapies. Transplantation of exogenous neural stem cells (NSCs) offers significant potential for therapeutic applications; however, challenges remain, including substantial cell loss, uncontrolled differentiation, and limited tissue integration within inflammatory microenvironments. Furthermore, the workflow associated with traditional NSC transplantation—including cryopreservation, thawing, transportation, and injection—remains fragmented, resulting in systemic limitations. These issues manifest as reduced cell viability and stemness, an elevated risk of contamination, and dosing inaccuracies. All these significantly impede clinical translation. An integrated system for NSC preservation, transport, and transplantation is required to meet the following criteria: (i) maintenance of high cell viability and stemness post-cryopreservation and thawing; (ii) modulation of the acute-phase immune microenvironment; (iii) regulation of the differentiation fate of transplanted NSCs; (iv) injectable, standardized, and closed-system operation. To meet these requirements, we established a comprehensive cryopreservation, thawing, and transplant (CTT) integrated platform. Utilizing the bioactive material PM-BMH@Exo, this platform enables seamless end-to-end workflow integration through a mechanism that preserves bioactivity. It not only ensures high viability retention and directed differentiation of NSCs but also effectively mitigates the rapid viability decline of cells observed after traditional cryopreservation. Furthermore, the system enables closed-loop operations spanning cryopreservation, thawing, and minimally invasive injection. It breaks through systemic bottlenecks from multi-step procedures, comprehensively enhancing the timeliness and standardization of therapeutic interventions. We systematically evaluated the system's feasibility and efficacy via in vitro and in vivo experiments. This study presents a technologically viable and clinically compatible pathway with potential applications for SCI repair.

A new method is proposed for detecting typical melamine dopants in food using surface-enhanced Raman scattering (SERS) biosensing technology. Melamine specific aptamer was used as the identification probe, and gold magnets (AuNPs@MNPs) and small gold nanoparticles (AuNPs@MBA) were used as the basis for Raman detection. The Raman signal of the detection system can directly detect melamine quantitatively. Under optimized conditions, the detection of melamine was carried out in the low concentration range of 0.001–500 mg/kg, the enhancement factor (EF) was 2.3 × 10⁷, and the detection limit was 0.001 mg/kg. The method is sensitive and rapid, and can be used for the rapid detection of melamine in the field environment. Graphical Abstract

Food is consumed by humans, which is indispensable to human life. Therefore, considerable attention of the whole society has been paid to food safety. Over the last few years, dramatic social development has brought new challenges to food safety, making developing new and quick methods for on‐site food safety testing an important necessity. As a result, DNA‐fueled molecular machines, characterized by high efficiency, accuracy, and sensitivity in testing, have come into the spotlight, based on which sensors can be constructed to detect toxic and harmful substances in food products. This study reviewed recent research on several DNA‐fueled molecular machines, including DNA tweezers, DNA walkers, and DNA origami, for rapidly detecting toxic and harmful substances. Based on the above studies, the sensitivity and timeliness of several DNA molecular machines were summarized and compared, and the development prospect of DNA fuel molecular machines in the field of food safety detection was prospected.

To optimize the single centrifugation preparation protocol of rat platelet-rich plasma (PRP). The arterial blood of rats obtained by carotid artery intubation was collected by heparin sodium anticoagulant tubes, and then the blood divided into sterile EP tubes, adjusting the red blood cell concentration with normal saline, while rat PRP was prepared by centrifugation under different conditions (the centrifugal force was 200×g-240×g, and the centrifugal time was 8-12 min). Subsequently, the blood cell count and quality evaluation of anticoagulat whole blood and PRP were performed by hematology analyzer and flow cytometry, respectively, and the differences between different groups were compared. The red blood cell concentration to (5.5-6.5)×10¹²/L after anticoagulation of rat whole blood was good for PRP extraction. When the blood samples was centrifuged at 220×g for 10 min, the platelet recovery rate was the highest［(53.52±0.63)%］. The level of apoptosis and activation of plateles in PRP were not significantly different compared to whole blood(P>0.05), and the release level of growth factor was significantly increased(P<0.05). It is a key to improve the PRP extraction efficiency by reducing the amount of mixed red blood cell, and this study successfully modified the preparation method of rat PRP, with platelets high recovery rate and stable quality.

To analyze the preservation effect and related influencing factors of human peripheral blood mononuclear cells under serum-free condition at 4 ℃. Human peripheral blood mononuclear cells were isolated by density gradient centrifugation, and stored at 4 ℃ under different cell concentrations, supplemented with human serum albumin, and glucose. The cell viability, total cell number, viable cell number and cell phenotype were detected during preservation of 72 h. With the prolongation of storage time, the number of human peripheral blood mononuclear cells gradually decreased(r=0.982). Compared with the cell concentration of (5-6)×10⁶ cells/ml, the cell number decreased more slowly when the cell storage concentration was (1-2)×10⁶ cells/ml; Adding human serum albumin and glucose can effectively improve the survival rate of human peripheral blood mononuclear cells, among which 2% human serum albumin has a better preservation effect; Compared with the blank control group, the analysis results of cell subsets showed that the downward trends of NK cells and T cells were significantly slowed after adding albumin and glucose. The cell density of (1-2)×10⁶/ml and 2% human serum albumin are more suitable for the preservation of PBMC, and 5% glucose can improve the preservation effect of human peripheral blood mononuclear cells at 4 ℃.