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Dynamic supramolecular assemblies, driven by noncovalent interactions, pervade the biological realm. In the synthetic domain, their counterparts, supramolecular polymers, endowed with remarkable self-repair and adaptive traits, are often realized through bioinspired designs. Recently, controlled supramolecular polymerization strategies have emerged, drawing inspiration from protein self-assembly. A burgeoning area of research involves mimicking the liquid–liquid phase separation (LLPS) observed in proteins to create coacervate droplets and recognizing their significance in cellular organization and diverse functions. Herein, we introduce a novel perspective on synthetic coacervates, extending beyond their established role in synthetic biology as dynamic, membraneless phases to enable structural control in synthetic supramolecular polymers. Drawing parallels with the cooperative growth of amyloid fibrils through LLPS, we present metastable coacervate droplets as dormant monomer phases for controlled supramolecular polymerization. This is achieved via a p-conjugated monomer design that combines structural characteristics for both coacervation through its terminal ionic groups and one-dimensional growth via a p-conjugated core. This design leads to a unique temporal LLPS, resulting in a metastable coacervate phase, which subsequently undergoes one-dimensional growth via nucleation within the droplets. In-depth spectroscopic and microscopic characterization provides insights into the temporal evolution of disordered and ordered phases. Furthermore, to modulate the kinetics of liquid-to-solid transformation and to achieve precise control over the structural characteristics of the resulting supramolecular polymers, we invoke seeding in the droplets, showcasing living growth characteristics. Our work thus opens up new avenues in the exciting field of supramolecular polymerization, offering general design principles and controlled synthesis of precision self-assembled structures in confined environments.

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Background: Irinotecan is a promising antitumor agent approved by FDA for intravenous use in colon cancer treatment either alone or in combination. It is a topoisomerase inhibitor and by blocking the topoisomerase-I enzyme, it causes DNA damage and results in cell death. However, it lacks selectivity and specificity for tumor cells, resulting in systemic toxicity. Thus, it is essential to reduce its side effects and improve therapeutic efficacy. Objective: The study aimed to improve the therapeutic efficacy and minimize the toxic effects of irinotecan by developing a fullerene functionalized biotin drug delivery system and adsorbing irinotecan on the surface of the functionalized fullerene-biotin complex. Methods: Fullerene (C60) has been observed as a potential drug delivery agent and the aminefunctionalized C60-NH2 was synthesized by functionalizing ethylenediamine on the surface of C60. The PEI functionalized C60 was further synthesized by polymerization of aziridine on the surface of C60- NH2. Biotin was attached by an amide linkage to C60-PEI and the anti-colon cancer drug irinotecan (IRI) was encapsulated (C60-PEI-Biotin/IRI). The C60-PEI-Biotin/IRI was characterized and evaluated for in vivo anti-colon cancer activity in rats and the results were compared with the parent drug irinotecan. Results: The results showed that C60-PEI-Biotin/IRI conjugate had a controlled release profile according to in vitro HPLC studies. Moreover in vivo anti-tumor studies suggested that the conjugate proved to be less toxic to vital organs and had high efficacy towards tumor cells. Statistical studies confirmed less tumor index and tumor burden in the case of conjugate when compared to irinotecan. Conclusion: It is hypothesized that the conjugate (C60-PEI-Biotin/IRI) could cross the cell membrane easily through overexpressed biotin receptors on the cell surface of colon cancer cells and showed better efficacy and less toxicity in comparison to IRI in the colon cancer rat model.

Supramolecular assemblies have been gaining attention in recent years in the field of drug delivery because of their unique formulation possibilities and adaptive behavior. Their non-covalent nature allows for their self-assembly formulation and responsiveness to stimuli, an appealing feature to trigger a therapeutic action with spatiotemporal control. However, facing in vivo conditions is very challenging for non-covalent structures. Dilution and proteins in blood can have a direct impact on self-assembly, destabilizing the supramolecules and leading to a premature and uncontrolled cargo release. To rationalize this behavior, we designed three monomers exhibiting distinct hydrophobic cores that self-assemble into photo-responsive fibers. We estimated their stability–responsiveness trade-off in vitro, finding two well-separated regimes. These are low-robustness regime, in which the system equilibrates quickly and responds readily to stimuli, and high-robustness regime, in which the system equilibrates slowly and is quite insensitive to stimuli. We probed the performance of both regimes in a complex environment using Förster resonance energy transfer (FRET). Interestingly, the stability–responsiveness trade-off defines perfectly the extent of disassembly caused by dilution but not the one caused by protein interaction. This identifies a disconnection between intrinsic supramolecular robustness and supramolecular stability in the biological environment, strongly influenced by the disassembly pathway upon protein interaction. These findings shed light on the key features to address for supramolecular stability in the biological environment.

Natural systems have been an inspiration to synthetic supramolecular chemistry. Synthetic demonstrations of dissipative biological systems such as actin filaments are a formidable scientific challenge in attaining future life-like materials. Dynamic instability of such structures beckons control of self-organization in the temporal regimes. In this study, we present a fuel-dependent helical assembly of a supramolecular polymer. We further attempt the synthetic manifestation of a temporally programmable self-assembly. Additionally, the fuel-induced chiral (re)organization with the employment of various enzymes singularly and in tandem have resulted in designing a multistate transient self-assembly. These parameter modulations result in controllable lifetimes and rates. We thus report, for the first time, a temporally programmed multistate reorganization of self-assembly.

The dynamic properties of supramolecular polymers enable new functionality beyond the limitations of conventional polymers. The mechanism of the monomer exchange between different supramolecular polymers is proposed to be closely associated with local disordered domains within the supramolecular polymers. However, a direct detection of such heterogeneity has never been experimentally probed. Here, we present the direct visualization of the local disordered domains in the backbone of supramolecular polymers by a super-resolution microscopy technique: Nile Red-based spectrally resolved point accumulation for imaging in nanoscale topography (NR-sPAINT). We investigate the local disordered domains in trisamide-based supramolecular polymers comprising a (co)assembly of benzene-1,3,5-tricarboxamide (BTA) and a variant with one of the amide bonds inverted (iBTA). The NR-sPAINT allows us to simultaneously map the spatial distribution and polarity of the local disordered domains along the polymers with a spatial precision down to ∼20 nm. Quantitative autocorrelation and cross-correlation analysis show subtle differences in the spatial distribution of the disordered domains between polymers composed of different variants of BTA monomers. Further, statistical analysis unraveled high heterogeneity in monomer packing at both intra- and interpolymer levels. The results reported here demonstrate the necessity of investigating the structures in soft materials at nanoscale to fully understand their intricacy.

Supramolecular materials due to their ordered arrangement, and efficient charge transport, exhibit great potential in optoelectronic applications. Nonetheless, precise structural control over the length and dispersity of supramolecular polymers is crucial for optimizing their properties and performance. Although recent advancements in living supramolecular polymerization (LSP) offer strategies for this control, research so far has primarily focused on structural aspects, overlooking the exploration of their functional implications. Moreover, studies have predominantly been conducted in organic media. In this study, we aim to utilize the LSP for structural control of functionally active supramolecular polymers in aqueous media. For this, we synthesized core-substituted naphthalene diimide-based (cNDI) fluorophores appended with chiral peptides. The initial control over the length and dispersity of the supramolecular polymer was attained by LSP where the resulting supramolecular polymer shows circularly polarized luminescence (CPL) property with efficient glum(dissymmetry factor) of 1.3 (±0.03) × 10–3. Further structural control was achieved by seeding approaches where the system shows highly efficient seeding in aqueous media. This new insight not only advances our understanding of the utilization of LSP for structural control in functionally active materials but also paves the potential utilization of LSP for biological applications.

Modern agriculture has entered an era of technological plateau where intervention of smarter technology like nanotechnology is imminently required for making this sector economically and environmentally sustainable. Throughout the world, researchers are trying to exploit the novel properties of several nanomaterials to make agricultural practices more efficient. Core/shell nanoparticles (CSNs) have attracted much attention because of their multiple attractive novel features like high catalytic, optical, and electronic properties for which they are being widely used in sensing, imaging, and medical applications. Though it also has the promise to solve a number of issues related to agriculture, its full potential still remains mostly unexplored. This review provides a panoramic view on application of CSNs in solving several problems related to crop production and precision farming practices where the wastage of resources can be minimized. This review also summarizes different classes of CSNs and their synthesis techniques. It emphasizes and analyzes the probable potential applications of CSNs in the field of crop improvement and crop protection, detection of plant diseases and agrochemical residues, and augmentation of chloroplast mediated photosynthesis. In a nutshell, there is enormous scope to formulate and design CSN-based smart tools for applications in agriculture, making this sector more sustainable.

Multicomponent supramolecular copolymerization promises to construct complex nanostructures with emergent properties. However, even with two monomeric components, various possible outcomes such as self-sorted supramolecular homopolymers, a random (statistical) supramolecular copolymer, an alternate supramolecular copolymer, or a complex supramolecular block copolymer can occur, determined by their intermolecular interactions and monomer exchange dynamics and hence structural prediction is extremely challenging. Herein, we target this challenge and demonstrate unprecedented two-component sequence controlled supramolecular copolymerization by manipulating thermodynamic and kinetic routes in the pathway complexity of self-assembly of the constitutive monomers. Extensive molecular dynamics simulations provided useful mechanistic insights into the monomer exchange rates and free energy of interactions between the monomers that dictate the self-assembly pathway and sequence. The fluorescent nature of core-substituted naphthalene diimide monomers has been further utilized to characterize the three sequences via Structured Illumination Microscopy (SIM).

Unprecedented spatiotemporal control exhibited by natural systems has aroused interest in the construction of its synthetic mimics. Cytoskeleton proteins utilize fuel-driven dissipative self-assembly to temporally regulate cell shape and motility. Until now, synthetic efforts have majorly contributed to fundamental strategies; however, temporally programmed functions are rarely explored. Herein, we work toward alleviating this scenario by using a charge-transfer (CT) based supramolecular polymer that undergoes structural changes under the effect of a redox fuel. The structural changes in supramolecular assembly amplify into observable macroscopic and material property changes. As a result, we achieve transient chemochromism,  a self-erasing ink and self-regenerating hydrogel, whose temporal profile can be regulated by varying the concentrations of the chemical cues (fuel and enzyme). The redox-mediated transient functions in the CT based supramolecular polymer pave way to create next-generation active, adaptive, and autonomous smart materials.

ABSTRACTPlants play an important role in the well-being of human beings and have been witnessed by their presence in the Rigveda and Ayurveda. Among those plants, Morus spp. is the one having versatile nature because of the presence of numerous phytochemicals in its different parts and also termed as ‘Kalpa Vruksha’. A wide range of the phytochemicals present in the leaves, fruit, root and wood of Morusbecause of which they possess wide range of biological functions (antidiabetic, antiobesity, antiinflammatory, anticancer, antibacterial, antioxidant, antiviral, cytoprotective and neuroprotective activities etc.). The plant is being utilised traditionally for development of different food products as well as treatment of various diseases. Recently, the researchers took a shift for the efficient utilisation of different parts of the plant for development of various value-added food products. The fruit-based products includes wine, vinegar, jelly, jam, biscuits, bread, squash, yoghurt, cosmetic cream, whereas, leaf-based products includes tea, toothpaste, pastry etc. However, the plant is still lacking its identity at the commercial scale. However, at commercial scale, a kind concern of the industrialists is required towards its effective and efficient utilisation as food, feed and value-added products with the aim to make it available throughout the year.

The air–water interface is an ideal platform to produce two-dimensional (2D) structures involving anything from simple organic molecules to supramolecular moieties by exploiting hydrophobic–hydrophilic interactions. Here, we show, using grazing incidence X-ray scattering, the formation of a 2D ordered structure of a charge-transfer (C-T) complex, namely, dodecyl methyl viologen (DMV) as acceptor and coronene tetracarboxylate potassium salt (CS) as donor, at the air–water interface. We have observed a phase transition in the 2D ordered structure as the area per molecule is decreased with increasing surface pressure in a Langmuir trough. The high-pressure ordering of the hydrocarbon chains associated with DMV destroys long-range C-T conjugation of DMV and CS at the air–water interface. Our results also explain the formation of DMV–CS cylindrical reverse micelles and eventually long nanowires that get formed in the self-assembly process in the bulk medium to preserve both the C-T conjugation and the organic tail–tail organization.

The urge towards a precise control over structure and function of supramolecular polymers has recently aroused interest in temporally controlled supramolecular polymerization. The field is divided into two; living and transient supramolecular polymerization. The former deals with structural control such as length and dispersity, analogous to living polymerization in conventional polymers. The latter requires a temporally controlled switching of a structural/functional state in a supramolecular polymer. Such a control has been inspired by nature that has a precise control over spatial and temporal regimes. In this account, we describe the necessity and challenges in achieving temporal control over supramolecular polymerization. We have reviewed important reports that have attempted to obtain living and transient supramolecular polymerization. Although there has been significant advancement, the field is still in infancy due to lack of generalized schemes and designs, and we have thus discussed our perspective towards the future directions to obtain general design and next level complex supramolecular materials with spatio-temporal control.Recent interests towards living and transient supramolecular polymerization has uncovered the facet of temporal control in supramolecular polymers. To achieve temporal control, understanding of energy landscapes of supramolecular polymerization is important to build new and generalized strategies.

Mulberry (Morus albaL.) is having numerous natural phytocompounds, which possess nutritional and pharmaceutical value. Due to its perishable nature and limited availability, it is not yet much explored except for its value addition. However, the wholesomeness in terms of shape has been always ignored. Therefore, the aim of present study was to optimize the processing conditions for production of osmo-dehydrated (OD) mulberry and retaining the shape of the fruit. The effect of three process variables i.e., blanching time (0 to 180 s), syrup concentration (45 to 75 obrix) and drying temperature (45–60 °C) was evaluated on the quality attributes of OD mulberry. All the phytochemicals were significantly (p ≤ 0.05) affected during processing conditions. The optimized conditions for the development of OD mulberry were 170 s blanching time, 66.52°brix syrup concentration and 53.48 °C drying temperature with 0.84 desirability. All the variables possess an important role in the quality of mulberry as revealed during cluster analysis. The optimized sample had more nutritional and phytochemical potential as confirmed during the qualitative analysis. In a nutshell, it is concluded that optimized conditions can be used to produce OD mulberry along with maintenance of original shape and to make it available at off places and during off seasons.