A specific aggregation-induced emission-conjugated polymer enables visual monitoring of osteogenic differentiation

Abstract

Osteogenic differentiation is the basis of bone growth and repair related to many diseases, in which evaluating the degree and ability of osteogenic transformation is quite important and highly desirable. However, fixing or stopping the growth of cells is required for conventional methods to monitor osteogenic differentiation, which cannot realize the full investigation of the dynamic process. Herein, a new anion conjugated polymer featuring aggregation-induced emission (AIE) characteristics is developed with excellent solubility for in-situ monitoring the process of osteogenic differentiation. This novel polymer can bind with osteogenic differentiated cells, and the intracellular fluorescence increases gradually with the enhancement of osteogenic differentiation. Moreover, it possesses good biosafety with negligible effect on cell activity and osteogenic differentiation, which cannot be realized by the typical method of Alizarin Red S staining. Further study shows that the polymer crosses the cell membrane through endocytosis and enriches in lysosomes, whereas no obvious fluorescence is detected with other cells, including non-differentiated osteoblast cells, under the same conditions, demonstrating the high selectivity. This is the first fluorescent probe with excellent specificity to realize real-time observation of the process of osteogenic differentiation. Therefore, PTB-EDTA shows great promise in the study of osteogenic differentiation and related applications.

Testing active membranes for bone regeneration: A review

“…This test is normally performed at different time points to evaluate the evolution of the mineralization nodules (i.e. 7, 15 and 21 days) [48]. At the different time points, Alizarin Red solution is added to the membrane and washed several times with deionized water in order to reduce non-specific staining.…”

Conjugated Polymers with Aggregation‐Induced Emission Characteristics for Fluorescence Imaging and Photodynamic Therapy

“…By changing the side chains from OEGs to ethylenediaminetetraacetic acid (EDTA) and the co‐monomer of TPE from phenyl to benzothiadiazole units, Zhang, Qin and coworkers prepared a new AIE conjugated polymer of PTB‐EDTA by Suzuki polycoupling, which could be used to in situ monitor the process of osteogenic differentiation (Figure 2c) [12] . The EDTA moieties of PTB‐EDTA offer it excellent solubility, biocompatibility, and high affinity towards Ca 2+ , which are vital metal element for osteogenic differentiation.…”

“…Thanks to its high efficiency, metal‐free and spontaneous feature, and mild reaction conditions, we successfully established a lab‐in‐cell. In other words, the click polymerization was carried in living cells, which could be used to turn on and kill the cells (Figure 2e) [12] . By systematically investigating the in vitro click polymerization conditions, it had been proved that the TPE containing diamine ( 1 ) could spontaneously polymerize with the carbonyl group activated terminal diyne ( 2 ) in cells under physiological conditions, and an AIE polymer PAA with weight‐average molecular weight ( M w ) of 7300 was generated.…”

A Novel BODIPY Quaternary Ammonium Salt-Based Fluorescent Probe: Synthesis, Physical Properties, and Live-Cell Imaging

“…Small molecular probes with a high fluorescence signal are of use in cancer imaging development and play important roles in the study of biological activity and metabolism in cancer disease treatment (Gonzalez-Vera et al, 2020;Zhao et al, 2020;Zheng et al, 2020). There are many members in traditional fluorescent probes family, such as fluorescein, rhodamine, and some other potential probes (Chen et al, 2020;Ren et al, 2020;Zhong et al, 2020).…”