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Self-assembly of modified amino acids facilitate the formation of various structures that have unique properties and therefore serve as excellent bio-organic scaffolds for diverse applications. Self-assembly of Fmoc protected single amino acids has attracted great interest owing to their ease of synthesis and applications as functional materials. Smaller assembly units enable synthetic convenience and potentially broader adoption. Herein, we demonstrate the ability to control the morphologies resulting from self-assembly of Fmoc modified aliphatic single amino acids (Fmoc-SAAs) namely, Alanine, Valine, Leucine, Isoleucine, and Proline. Controlled morphological transitions were observed through solvent variation and the mechanism that allows this control was investigated using coarse-grained molecular dynamics simulations. These show that FmocA can form well defined crystalline structures through uniform parallel Fmoc stacking and the optimization of ion concentrations, which is not observed for the other Fmoc-SAAs. We demonstrate that Fmoc protected aliphatic single amino acids are novel scaffolds for the design of distinct micro/nanostructures through a bottom-up approach that can be tuned by control of the environmental parameters. [ABSTRACT FROM AUTHOR]

Primary care providers, including general practice teams (GPTs), are well positioned within the community to integrate cancer survivorship care into ongoing health management. However, roles of GPT members in delivery of cancer survivorship care have not been explored. The purpose of this study is to explore these roles from the perspectives of General Practitioners (GPs), Practice Nurses (PNs) and Practice Managers (PMs). An interpretive qualitative study using semi‐structured in‐depth telephone interviews with ten GPs, nine PNs and five PMs was conducted. Interviews were recorded, transcribed and analysed using grounded theory methods. Perspectives of roles in delivery of cancer survivorship care were highly variable. Variation was evident among perceptions of needs of cancer survivors, individual team members' scopes of practice, and individual professional knowledge and skills. A lack of clarity in roles and responsibilities of GPT members was thought to contribute to a lack of consistency in survivorship care. Reducing variations in perceptions of survivorship care in the primary care setting should be a priority. Such efforts may include development of practical guidance to support GPT members to clarify scopes of practice within the team. In addition to accessible comprehensive education programs, other innovative, tailored individualised education approaches may be helpful. System‐level support in clarifying and supporting the roles of the primary care team is needed to facilitate a survivorship delivery system at general practice level where those within GPT can ensure that individual patients' needs are met in a timely and effective manner. [ABSTRACT FROM AUTHOR]

The highly efficient and selective C(sp3)–S bond cross‐coupling method for the synthesis of 9‐thiolated fluorenes through a direct thiolation at 9‐C(sp3)–H of fluorenes with thiols is described. This reaction occurs at ambient conditions and shows good tolerance of functional groups including arylthiols and alkylthiols. A wide range of products is obtained in moderate to good yields. Besides, the reaction of benzothiophenol and fluorine generates unexpected 9‐benzylidene‐9H‐fluorene by eliminating hydrogen sulfide. A highly efficient and selective C(sp3)–S bond cross‐coupling method for the synthesis of 9‐thiolated fluorenes through a direct thiolation at 9‐C(sp3)–H of fluorenes with thiols is described. [ABSTRACT FROM AUTHOR]

Self-assembly of highly important biomolecules, such as proteins and peptides, has attracted tremendous interest in supramolecular construction of functional materials. However, as proteins and peptides are often immunogenic and their structures are complex, there is a strong demand to use amino acids as simpler building blocks. Still, mimicking the sophisticated structures and functions of natural materials by self-assembly of simpler and more basic units of biomolecules, such as amino acids, remains a formidable challenge. Inspired by metalion- associated crystallization of l-cystine in the urinary system, amino acid coordinated self-assembly is discussed as an original strategy for supramolecular construction of biomimetic materials. The resulting materials possess the features of uniform size, hierarchical architecture, and structural resemblance to biological structures. In addition, the self-assembly process can readily be adapted to simultaneous integration of various functional modules, providing materials with promising properties for biomimetic and biomedical applications. [ABSTRACT FROM AUTHOR]

Molecular self-assembly is a key direction for the fabrication of advanced materials. Yet, the physical properties of the formed assemblies are limited by the inherent characteristics of the specific building blocks. Here, we have applied a co-assembly approach to synergistically modulate the mechanical properties of peptide hydrogels, thereby forming extremely stable and rigid hydrogels. [ABSTRACT FROM AUTHOR]

Amino acids and short peptides modified with the 9-fluorenylmethyloxycarbonyl (Fmoc) group possess eminent self-assembly features and show distinct potential for applications due to the inherent hydrophobicity and aromaticity of the Fmoc moiety which can promote the association of building blocks. Given the extensive study and numerous publications in this field, it is necessary to summarize the recent progress concerning these important bio-inspired building blocks. Therefore, in this review, we explore the self-organization of this class of functional molecules from three aspects, i.e., Fmoc-modified individual amino acids, Fmoc-modified di- and tripeptides, and Fmoc-modified tetra- and pentapeptides. The relevant properties and applications related to cell cultivation, bio-templating, optical, drug delivery, catalytic, therapeutic and antibiotic properties are subsequently summarized. Finally, some existing questions impeding the development of Fmoc-modified simple biomolecules are discussed, and corresponding strategies and outlooks are suggested. [ABSTRACT FROM AUTHOR]

Gel formation by an N-fluorenyl-9-methoxycarbonyl (Fmoc)-based molecule was investigated and the chirality amplification observed during the self-assembly process could be switched on and off by controlling the solvent environment. The molecules could form gel in mixed solvents of water and dimethyl sulfoxide (DMSO) at either a high water fraction to afford flat nanofibers or a low water fraction to generate nanofibers with supramolecular chirality. At a moderate fraction of water, the molecules self-assemble into a precipitate composed of nanosheets. Furthermore, the gels showed different mechanical properties and thermal stabilities. Mechanism studies showed that π–π stacking interactions between the aromatic Fmoc groups and hydrogen bondings between the amide groups played important roles in the self-assembly process of the different gels. This study strives to shed light on the tuning of chiral gels with various nanostructures via controlled self-assembly, which might have potential use in smart materials. [ABSTRACT FROM AUTHOR]

Peptide-tuned self-assembly of functional components offers a strategy towards improved properties and unique functions of materials, but the requirement of many different functions and a lack of understanding of complex structures present a high barrier for applications. Herein, we report a photosensitive drug delivery system for photodynamic therapy (PDT) by a simple dipeptide- or amphiphilic amino-acid-tuned self-assembly of photosensitizers (PSs). The assembled nanodrugs exhibit multiple favorable therapeutic features, including tunable size, high loading efficiency, and on-demand drug release responding to pH, surfactant, and enzyme stimuli, as well as preferable cellular uptake and biodistribution. These features result in greatly enhanced PDT efficacy in vitro and in vivo, leading to almost complete tumor eradication in mice receiving a single drug dose and a single exposure to light. [ABSTRACT FROM AUTHOR]

The formation of hydrogels by low molecular weight building blocks results in important supramolecular assemblies for technological applications. N-modified amino acids are especially interesting components for the organization of such structures due to their high association efficiency, inherent biocompatibility, and structural diversity. Fluorenylmethoxycarbonyl (Fmoc)-modified tyrosine (Fmoc-Tyr) has been extensively studied as a notably simple yet highly efficient hydrogelator. Here, we present the ability to use a combination of Fmoc-Tyr and catechol-containing Fmoc-3,4-dihydroxyphenylalanine (Fmoc-DOPA) to form a functional two-component hydrogel which combines the physical characteristics of the Fmoc-Tyr hydrogels and the functionality of the catechol groups. We demonstrate that a combination of the two building blocks results in the rapid formation of three-dimensional self-supporting gels. Rheological analysis indicated that the observed hybrid gel has a very high storage modulus, of the same order of magnitude as that of the Fmoc-Tyr gel. In addition to the envisioned mechanical properties, the combined gel also displayed a clear silver ion reduction activity. Taken together, we illustrate the ability to utilize two-component gels to achieve synergetic properties, combining rigidity and functionality. [ABSTRACT FROM AUTHOR]