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Abstract Despite multiple new‐drug approvals in recent years, prostate cancer remains a global health challenge because of the prostate cancers are resistant to androgen deprivation therapy. Here, we show that a small D‐phosphopeptide undergoes prostatic acid phosphatase (PAP)‐instructed self‐assembly for inhibiting castration‐resistant prostate cancer (CRPC) cells. Specifically, the installation of phosphate at the C‐terminal of a D‐tripeptide results in the D‐phosphopeptide. Dephosphorylating the D‐phosphopeptide by PAP forms uniform nanofibers that inhibit VCaP, a CRPC cell. A non‐hydrolyzable phosphate analogue of the D‐phosphopeptide, which shares similar self‐assembling properties with the D‐phosphopeptide, confirms that PAP‐instructed assembly is critical for the inhibition of VCaP. This work, for the first time, demonstrates PAP‐instructed self‐assembly of peptides for selective inhibiting CRPC cells. 

A comparative spectroscopic investigation was conducted to evaluate the potential of Dy³⁺and Er³⁺doped Ga₂Ge₅S₁₃chalcogenide glass and CsCdCl3 crystal for suitability as gain media for mid-infrared lasers operating within the 4.1-4.8 (m spectral range. Both rare-earth ions exhibited broad mid-IR emissions at room temperature centered at ∼4.4-4.5 µm, attributed to the Dy³⁺:⁶H_11/2→⁶H_13/2and Er³⁺:⁴I_9/2→⁴I_11/2transitions. The fluorescence lifetimes of these mid-IR transitions varied significantly between these two host materials. Dy³⁺and Er³⁺doped CsCdCl₃crystals exhibited long lifetimes of ∼9-12 ms, while the same ions in Ga₂Ge₅S₁₃glass yielded lifetimes in the range of ∼1 ms. Temperature-dependent lifetime measurements further confirmed the role of multiphonon relaxation in Dy³⁺: Ga₂Ge₅S₁₃, although fitting with the temperature dependence of the multiphonon energy-gap law indicated the presence of additional nonradiative decay channels, likely involving impurity interactions. In contrast, Er³⁺emissions exhibited minimal temperature dependence across both hosts, with measured lifetimes closely matching calculated radiative values. Judd-Ofelt analyses revealed radiative properties and transition probabilities comparable to other low-maximum-phonon-energy rare-earth-doped hosts, with the studied Dy³⁺doped host materials standing out by offering sigma-tau products several times higher than those of Er³⁺in the same hosts. 

In this work, we use experimental and theoretical techniques to study the origin of the boosted hydrogen evolution reaction (HER) catalytic activity of two pyridyl-pyrrolidine functionalized C₆₀fullerenes. 

Polyurethanes (PUs) are a highly adaptable class of biomaterials that are among some of the most researched materials for various biomedical applications. However, engineered tissue scaffolds composed of PU have not found their way into clinical application, mainly due to the difficulty of balancing the control of material properties with the desired cellular response. A simple method for the synthesis of tunable bioactive poly(ethylene glycol) diacrylate (PEGDA) hydrogels containing photocurable PU is described. These hydrogels may be modified with PEGylated peptides or proteins to impart variable biological functions, and the mechanical properties of the hydrogels can be tuned based on the ratios of PU and PEGDA. Studies with human cells revealed that PU–PEG blended hydrogels support cell adhesion and viability when cell adhesion peptides are crosslinked within the hydrogel matrix. These hydrogels represent a unique and highly tailorable system for synthesizing PU-based synthetic extracellular matrices for tissue engineering applications. 

A visible-light-responsive arylazopyrazole-functionalized phenylalanine (4-MeS-AAP-NF) derived ligand was designed and synthesized, and it was found to form metallogels with reversible photo-responsive properties in mixed methanol/water (MeOH/H2O) solvents. The gelation behavior of the 4-MeS-AAP-NF ligand in the presence of different divalent metal ions in mixed methanol/water (MeOH/H2O) solvents at pH~11.60 was studied. It was found that the 4-MeS-AAP-NF ligand alone could not self-assemble to form any gels. However, in the presence of divalent metal ions, it readily formed the assembled metallogels in an alkaline aqueous/methanol solution with various morphologies. The results suggest that the gelation process was triggered by divalent metal ions. The presence of the AAP moiety in the gel matrix rendered the metallogel assemblies photo-responsive, and the reversible gel-to-sol phase transition was studied by UV-vis spectroscopy. The gels showed a slow, reversible visible-light-induced gel-to-sol phase transition under blue (λ = 405 nm) and then sol-to-gel transition by green light (λ = 530 nm) irradiation, resulting in the re-formation of the original gel state. The morphology and viscoelastic properties of the yellow–orange opaque metallogels were characterized by scanning electron microscopy (SEM) and rheological measurement, respectively.