University Of Jinan

Neural stem cells (NSCs) transplantation offers a promising therapeutic approach for spinal cord injury (SCI), addressing the challenge of neuron irreparability. However, the uncontrolled differentiation of transplanted NSCs and the inflammatory environment at the injury site limit the efficacy of cell-based treatments. To overcome these obstacles, simultaneously regulating NSCs differentiation and reshaping immune microenvironment is vital for enhancing the effectiveness of cell therapy. In this study, we proposed calcium phytate nanoparticles (Ca-PA NPs) as synergistic regulators capable of promoting neuronal differentiation and regulating the polarization of immune cells. This approach leverages the coordination properties of calcium ions and phytic acid, as well as the decomposition characteristics of calcium phytate. The nanoparticles can be endocytosed by NSCs or microglia, and decomposed in their lysosomes, forming the intracellular small molecule/ion storms. In vitro, NSCs endocytosing Ca-PA NPs predominantly differentiate into neurons, while microglia internalizing the nanoparticles transition from a pro-inflammatory M1 phenotype to a neuroprotective M2 phenotype. Importantly, the animal experiments proved that Ca-PA NPs significantly enhanced functional recovery in SCI mice by synergistically promoting neuronal differentiation of transplanted NSCs and reshaping immuno-microenvironment. These findings open a new route to design nano-regulators for immune microenvironment involved stem cell therapy of SCI.

Electrochemiluminescence (ECL) technology has become an essential analytical methodology in biomolecular detection, attaining both profound research advancements and extensive practical applications in this domain. Herein, we used carboxylated mesoporous silica (MSN-COOH) as a container to encapsulate Tris(2,2-bipyridyl)ruthenium(II)²⁺ (Ru(bpy)₃²⁺)-a luminophore-in its pores to achieve enrichment (RuMSN). The reactive intermediates Ru(bpy)₃³⁺ and TPrA^•+ are attracted by the electro-negative carboxyl group on the MSN-COOH surface, substantially reducing the reaction distance and improving the ECL response efficiency. The flower-like NiFe layered double hydroxide (NiFe-LDH) nanostructure possesses significantly high specific surface area and good electrocatalytic performance, while gold nanoparticles also demonstrate excellent electrical conductivity and biocompatibility. To enhance sensor sensitivity, gold nanoparticles were loaded onto the NiFe-LDH surface forming the Au@NiFe-LDH composite, which improves performance by enhancing conductive properties and increasing antigen-antibody binding sites. This study established a sandwich-configuration electrochemiluminescence detection platform capable of highly sensitive PSA analysis.The biosensor demonstrated excellent stability, specificity and selectivity, with a linear detection range of 0.1 pg/mL-50 ng/mL and a detection limit as low as 63 fg/mL (S/N = 3). This confirms the clinical application value of the detection system in the early screening of prostate cancer.

Nitrite (NO₂^-), a natural component of the nitrogen cycle, poses significant risks to both ecosystems and human health when present as a pollutant. Hence, it is essential to develop detection methods with high selectivity, sensitivity, and rapid response for measuring nitrite levels in water. This study introduces a novel colorimetric fluorescent probe PQ-N, which specifically recognizes NO₂^- in diverse environments including water, soil, and food. The probe features ultra-low detection limits of 0.16 μM (for fluorescence spectroscopy) and 0.81 μM (for absorption spectroscopy), a linear detection range of 0-10 μM, as well as strong resistance to interference from complex environmental matrices. Moreover, a new sensing platform based on test strips combined with smartphone-assisted chemical dosimeters is established, enhancing the convenience and reliability of on-site nitrite detection. Validation using real samples shows agreement with national standard methods, confirming the probe's practical applicability. This research offers an effective and accurate tool for nitrite detection, contributing valuable support for ecological safety assessments.