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Graphical abstract Highlights • A colorimetric method based on polydiacetylene liposomes was developed for the detection of alkaline phophatase (ALP). • Ca2+ could induce clear color changes of PDA liposomes from blue to red, while PPi can inhibit this process. • The presence of ALP can remove the inhibition effect of PPi and restore the colorimetric responses. • The detection appoach showed high sensitivity and selectivlty for ALP with the detection limit of 5.4 U/L. • This method could be extended for inhbitor effect evluation and ALP assay in serum samples with acceptable accuracy. Abstract The detection of alkaline phosphatase (ALP) activity has received great attention since its activity in serum is highly associate with various human diseases. Herein, we describe a simple yet effective colorimetric assay for ALP activity based on polydiacetylene (PDA) and competitive binding of pyrophosphate (PPi) with calcium ions (Ca2+). PDA liposomes prepared from 10,12-pentacosadiynoic acid (PCDA) display the distinct blue-to-red color transition towards Ca2+, which can be effectively blocked by PPi due to the ultra-strong binding ability of Ca2+ with PPi. Since PPi can be specifically hydrolyzed into orthophosphate (Pi) by ALP, the negative effect of PPi could be removed when ALP is introduced into the system, thereby producing a colorimetric signal relying on ALP activity. Based on this strategy, ALP was sensitively and selectively detected with a limit of detection of 5.4 U/L. Besides, the proposed sensing method was successfully applied to evaluate the inhibitor efficiency. Detection of ALP in real human serum samples could also be achieved by this system with acceptable accuracy. As the proposed PDA liposome sensor is simple and straightforward, this strategy holds great potential as a promising alternative for ALP-based clinic diagnosis or biological research. [ABSTRACT FROM AUTHOR]

Abstract: Organic optoelectronic materials with high fluorescence quantum yield, both in solution and in the solid state, have attracted considerable interest in recent years. In this work, we designed and synthesized three triarylborane-terminalized branched π-conjugative compounds, including two C 3-symmetric π-3A(acceptor) triarylboron dyes: 2,7,12-tri(5-(dimesitylboryl)thiophen-2-yl)-5,5′,10,10′,15,15′-hexaethyltruxene and 2,7,12-tri((5-(dimesitylboryl)thiophen-2-yl)ethynyl)-5,5′,10,10′,15,15′-hexaethyltruxene, and a 2D(donor)-π-A asymmetric dye: 2,7-di(N,N-diphenylamino)-12-(5-(dimesitylboryl)thiophen-2-yl)-5,5′,10,10′,15,15′-hexaethyltruxene. The three compounds displayed prominent optical properties. The ethynyl spaced thiophene analogue emitted intense fluorescence both in the THF solution and in the solid state with excellent quantum yields. Interestingly, their solid powders showed a very different fluorescence colour from their respective THF solution. The results of theoretical calculations were in good agreement with the experimental absorption and CV spectra. The high reversibility of the three boron-containing dyes in their redox process indicates substantial stability of the produced species, which make them promising light-emitting materials. [Copyright &y& Elsevier]

As common progenitor cells of osteoblasts and adipocytes, bone marrow mesenchymal (stromal) stem cells (BMSCs) play key roles in bone homeostasis, tissue regeneration, and global energy homeostasis; however, the intrinsic mechanism of BMSC differentiation is not well understood. Plasticity in energy metabolism allows BMSCs to match the divergent demands of osteo-adipogenic differentiation. Targeting BMSC metabolic pathways may provide a novel therapeutic perspective for BMSC differentiation unbalance related diseases. This review covers the recent studies of glucose, fatty acids, and amino acids metabolism fuel the BMSC differentiation. We also discuss recent findings about energy metabolism in BMSC differentiation. Glucose, fatty acids, and amino acids metabolism provide energy to fuel BMSC differentiation. Moreover, some well-known regulators including environmental stress, hormone drugs, and biological and pathological factors may also influence BMSC differentiation by altering metabolism. This offers insight to the significance of metabolism on BMSC fate determination and provides the possibility of treating diseases related to BMSC differentiation, such as obesity and osteoporosis, from a metabolic perspective. [ABSTRACT FROM AUTHOR]

Aggregation-induced emission (AIE) has attracted considerable interest in recent years. An understanding of the underlying mechanisms for the AIE phenomena is also of great importance. Here, we synthesized four fluorenone derivatives, which all show typical AIE properties. Their enhanced solid-state luminescence showed a 160 nm red-shift (from 380 to 540 nm) in comparison to their luminescence in dilute tetrahydrofuran (THF) solutions. The single-crystal structure and photophysical properties revealed that the bathochromic luminescence is due to the formation of static excimers. To further demonstrate the AIE mechanism of static excimers, rather than restricted intramolecular rotation (RIR), we designed a diphenylfluorenone-diboronic acid adduct, which can react with d -glucose to create structurally rigid oligomers, resulting in the restriction of intramolecular rotations. The spectral change in the d -glucose titration of the adduct indicated that the bathochromic AIE of these fluorenone compounds cannot possibly be caused by RIR and conformational planarization. [ABSTRACT FROM AUTHOR]

Organic solid-state luminescence materials with aggregation-induced emission enhancement have attracted considerable interest in recent years. In this work, we develop a class of 2,7-diphenylfluorenone derivatives that exhibit prominent aggregation-induced emission properties with high solid-state quantum yields. Their solid-state powders show a ∼160 nm bathochromically shifted fluorescence and longer lifetime compared to their emission in dilute THF solution. The X-ray single structures and photophysical properties reveal that the mechanism of aggregation-induced emission in this class of fluorenone compounds is due to the formation of static excimers through hydrogen bonds in the solid state. The emission of their THF solution peaked at 380 nm and originates from the single molecule and the emission of their solid-state powder peaked at 550 nm originates from the excimers. The aggregation-induced emission properties and luminescence mechanism are further verified by the design of 2,7-diphenylfluorenone-diboronic acid adduct, which exhibited weak luminescence in high pH buffer and red-shifted strong luminescence in acidic buffer. [ABSTRACT FROM AUTHOR]