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Plant photosynthetic machinery is the main source of acquisition and conversion of solar energy to chemical energy with the capacity for autonomous self-repair. However, the major limitation of the chloroplast photosystem is that it can absorb light only within the visible range of the spectrum, which is roughly 50% of the incident solar radiation. Moreover, the photosynthetic apparatus is saturated by less than 10% of available sunlight. If the capacity of solar light absorption and the transmission of resulting photons through the photosynthetic electron transport chain (ETC) can be extended, the overall efficiency of photosynthesis can be improved. The plant nanobionic approach can address this via the introduction of nanoparticles into or in the vicinity of the photosynthetic machinery/chloroplast. We have studied this exceptional nanobionic-mediated capability of two optically active nanostructures and evaluated the impact of their optical properties on plant photosynthesis. Our study revealed that metal (Ag) and core-shell metal nanostructures (AgS) can increase light absorption and improve electron transport through ETC. Both nanostructures were found to have a beneficial effect on the photoluminescence property of the isolated chloroplast. Translocation studies confirmed systemic transportation of the nanomaterial in different plant tissues. The primary growth parameters showed no detrimental effect until 21 days of treatment on Arachis hypogaea . The nano silver/silica core/shell structure (AgS) was found to be more advantageous over nano silver (AgNP) in photon entrapment, light-dependent biochemical reactions, and toxicity parameters. In the future, these nanostructures can enhance photosynthesis by increasing light absorption and resulting in higher assimilatory power generation in the form of ATP and NADPH. This approach may lead to a paradigm shift toward a sustainable method for the configuration of plant chloroplast-based hybrid energy harvesting devices., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

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.

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 π-conjugated monomer design that combines structural characteristics for both coacervation through its terminal ionic groups and one-dimensional growth via a π-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.

Multicomponent supramolecular polymers offer versatile dynamic and functional properties; however, the influence of the monomer chemical structures on their structure-dynamics-function relationship remains unclear. In this study, we investigated the subtle variations in monomer interactions using one monomer and its two dopant derivatives, with functionalization away from the self-assembling core. We systematically investigated their multicomponent supramolecular polymers using a combination of spectroscopy and super-resolution microscopy. Our results highlight the significant impact of the supplementary intermolecular interactions, resulting from the functional motifs located away from the core and present in small quantities, on the microstructure and dynamics. Thus, a comprehensive approach, combining spectroscopy, microscopy, and well-designed experiments, is essential for assessing multicomponent supramolecular polymers. These findings have implications for the rational design of functional multicomponent supramolecular materials.

Recruiting endogenous antibodies to the surface of cancer cells using antibody-recruiting molecules has the potential to unleash innate immune effector killing mechanisms against antibody-bound cancer cells. The affinity of endogenous antibodies is relatively low, and many currently explored antibody-recruiting strategies rely on targeting over-expressed receptors, which have not yet been identified in most solid tumors. Here, both challenges are addressed by functionalizing poly(propyleneimine) (PPI) dendrimers with both multiple dinitrophenyl (DNP) motifs, as anti-hapten antibody-recruiting motifs, and myristoyl motifs, as universal phospholipid cell membrane anchoring motifs, to recruit anti-hapten antibodies to cell surfaces. By exploiting the multivalency of the ligand exposure on the dendrimer scaffold, it is demonstrated that dendrimers featuring ten myristoyl and six DNP motifs exhibit the highest antibody-recruiting capacity in vitro. Furthermore, it is shown that treating cancer cells with these dendrimers in vitro marks them for phagocytosis by macrophages in the presence of anti-hapten antibodies. As a proof-of-concept, it is shown that intratumoral injection of these dendrimers in vivo in tumor-bearing mice results in the recruitment of anti-DNP antibodies to the cell surface in the tumor microenvironment. These findings highlight the potential of dendrimers as a promising class of novel antibody-recruiting molecules for use in cancer immunotherapy., (© 2023 Wiley-VCH GmbH.)

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 (C 60 ) has been observed as a potential drug delivery agent and the aminefunctionalized C 60 -NH 2 was synthesized by functionalizing ethylenediamine on the surface of C 60 . The PEI functionalized C 60 was further synthesized by polymerization of aziridine on the surface of C 60 - NH2. Biotin was attached by an amide linkage to C 60 -PEI and the anti-colon cancer drug irinotecan (IRI) was encapsulated (C 60 -PEI-Biotin/IRI). The C 60 -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 C 60 -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 (C 60 -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., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

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.

Fascinating properties are displayed by synthetic multicomponent supramolecular systems that comprise a manifold of competitive interactions, thereby mimicking natural processes. We present the integration of two reentrant phase transitions based on an unexpected dilution-induced assembly process using supramolecular polymers and surfactants. The co-assembly of the water-soluble benzene-1,3,5-tricarboxamide (BTA-EG 4 ) and a surfactant at a specific ratio yielded small-sized aggregates. These interactions were modeled using the competition between self-sorting and co-assembly of both components. The small-sized aggregates were transformed into supramolecular polymer networks by a twofold dilution in water without changing their ratio. Kinetic experiments show the in situ growth of micrometer-long fibers in the dilution process. We were able to create systems that undergo fully reversible hydrogel-solution-hydrogel-solution transitions upon dilution by introducing another orthogonal interaction.

Fullerenes are the allotropic form of carbon consisting of a cage-like structure due to which they have attained special attention from researchers since their discovery in 1985. The unique chemical and physical properties of fullerene have attracted researchers to develop a variety of its biomedical applications. The closed cage structure of fullerenes can be used for various drug delivery applications and can also act as a medium for controlled release formulations. The development of targeted anticancer drug and drug delivery systems is one of the most challenging fields, which is widely studied and researched. In this review, we aim to provide a comprehensive review on the most recent advances in fullerenes as targeted anticancer drug delivery systems along with their therapeutic applications and challenges, thus serving the pharmaceutical and biotechnology community., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Background: Camptothecin is a naturally occurring alkaloid obtained from the stem wood of the Chinese tree, Camptotheca acuminata. It exerts pharmacological effects due to its ability to selectively inhibit the type-I topoisomerase DNA nuclear enzyme. Several semisynthetic analogs of camptothecin have been synthesized to date possessing antitumor activity., Objective: Camptothecin (CPT) is one of the most promising anticancer drugs but it produces various side effects because of its non-selectivity towards cancer cells. To overcome these adverse effects, we synthesized biotin conjugate of camptothecin, which was linked via a self-immolative disulfide linker (CPT-SS-Biotin)., Methods: Biotin conjugated camptothecin linked through a disulfide bond was synthesized following schemes, and the structural characterization was carried out. The stability and drug release studies were performed in the presence of glutathione (GSH) while in vitro studies were performed on 4T1 tumor cell lines. In vivo pharmacological investigation was done using an antitumor Wistar rat model., Results: The stability and drug release studies were performed in the presence of glutathione (GSH), and CPT-SSBiotin was found to be physiologically stable moiety and can only be cleaved in the presence of GSH to release free CPT. The CPT-SS-Biotin showed higher toxicity in the biotin-overexpressing 4T1 tumor cell line with a lower IC50 value (8.44 μM) compared to camptothecin alone (IC 50 > 30 μM). CPT-SS-Biotin also showed 10.6% higher cellular uptake by cells in comparison to free camptothecin. The CPT-SS-Biotin was delivered to cells by binding to the biotin receptors on the cell surface, followed by energy-dependent endocytosis and internalization to cause cellular toxicity., Conclusion: In-vivo tumor suppression studies and in vitro cell line studies along with serological parameters and histopathological studies showed that conjugate produced a high therapeutic effect and remarkably reduced toxic effects in comparison to free CPT. The results suggested that biotinylation of camptothecin via disulfide linker can be a safe and efficacious method in cancer therapeutics., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

The characterization of newly synthesized materials is a cornerstone of all chemistry and nanotechnology laboratories. For this purpose, a wide array of analytical techniques have been standardized and are used routinely by laboratories across the globe. With these methods we can understand the structure, dynamics and function of novel molecular architectures and their relations with the desired performance, guiding the development of the next generation of materials. Moreover, one of the challenges in materials chemistry is the lack of reproducibility due to improper publishing of the sample preparation protocol. In this context, the recent adoption of the reporting standard MIRIBEL (Minimum Information Reporting in Bio-Nano Experimental Literature) for material characterization and details of experimental protocols aims to provide complete, reproducible and reliable sample preparation for the scientific community. Thus, MIRIBEL should be immediately adopted in publications by scientific journals to overcome this challenge. Besides current standard spectroscopy and microscopy techniques, there is a constant development of novel technologies that aim to help chemists unveil the structure of complex materials. Among them super-resolution microscopy (SRM), an optical technique that bypasses the diffraction limit of light, has facilitated the study of synthetic materials with multicolor ability and minimal invasiveness at nanometric resolution. Although still in its infancy, the potential of SRM to unveil the structure, dynamics and function of complex synthetic architectures has been highlighted in pioneering reports during the last few years. Currently, SRM is a sophisticated technique with many challenges in sample preparation, data analysis, environmental control and automation, and moreover the instrumentation is still expensive. Therefore, SRM is currently limited to expert users and is not implemented in characterization routines. This perspective discusses the potential of SRM to transition from a niche technique to a standard routine method for material characterization. We propose a roadmap for the necessary developments required for this purpose based on a collaborative effort from scientists and engineers across disciplines., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Synthetic water-compatible supramolecular polymers based on benzene-1,3,5-tricarboxamides (BTAs) have attracted a lot of interest in recent years, as they are uniquely suited to generate functional multicomponent biomaterials. Their morphologies and intrinsic dynamic behaviour mimic fibrous structures found in nature. Moreover, their modularity allows control of the density of functionalities presented on the surface of the fibres when using functionalized BTA monomers. However, such moieties generally comprise a functionality on only one of three side chains, resulting in lengthy synthetic protocols and limited yields. In this work, we avert the need for desymmetrization of the core by starting from commercially available 5-aminoisophthalic acid. This approach eliminates the statistical reactions and reduces the number of synthetic steps. It also leads to the inversion of the connectivity of one of the amides to the benzene core. By combining spectroscopy, light scattering and cryogenic transmission electron microscopy, we confirm that the inversed amide BTAs (iBTAs) form intermolecular hydrogen bonds and assemble into supramolecular polymers, like previously used symmetrical BTAs, albeit with a slight decrease in water solubility. Solubility problems were overcome by incorporating iBTAs into conventional BTA-based supramolecular polymers. These two-component mixtures formed supramolecular fibres with a morphology and dynamic behaviour similar to BTA-homopolymers. Finally, iBTAs were decorated with a fluorescent dye to demonstrate the synthesis of functional monomers, and to visualize their co-assembly with BTAs. Our results show that functionality can be introduced into supramolecular polymers with monomers that slightly differ in their core structure while maintaining the structure and dynamics of the fibres.

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.

Adenosine triphosphate (ATP) is a molecular unit of energy that drives various processes in the cellular environment. In this Minireview, we discuss the potential of physical and chemical properties of ATP for the development of bio-inspired, synthetic ATP-induced supramolecular systems with dynamic, stimuli-responsive and active assembly characteristics. Molecular design rules for ATP-induced assemblies with various architectures and their stimuli-responsive structural and functional response are categorized. Special attention is given to the immense potential of ATP-fuelled designs in the nascent field of transient/non-equilibrium supramolecular polymerization for the synthesis of lifelike temporally programmable soft materials. Finally, the existing dearth and fate of ATP-driven systems for future challenges are discussed., (© 2020 Wiley-VCH GmbH.)

Transient supramolecular self-assembly has evolved as a tool to create temporally programmable smart materials. Yet, so far single-component self-assembly has been mostly explored. In contrast, multicomponent self-assembly provides an opportunity to create unique nanostructures exhibiting complex functional outcomes, newer and different than individual components. Even two-component can result in multiple organizations, such as self-sorted domains or co-assembled heterostructures, can occur, thus making it highly complex to predict and reversibly modulate these microstructures. In this study, we attempted to create active bicomponent nanoparticle assemblies of orthogonally pH-responsive-group-functionalized gold and cadmium selenide nanoparticles with temporal microstructural control on their composition (self-sorted or co-assembly) in order to harvest their emergent transient photocatalytic activity by coupling to temporal changes in pH. Moving towards multicomponent systems can deliver next level control in terms of structural and functional outcomes of supramolecular systems., (© 2020 Wiley-VCH GmbH.)

Partially purified β-mannanase was immobilized on the modified matrix of sodium alginate-grafted-β-cyclodextrin. The Fourier-transform infrared spectroscopy (FTIR) and X-ray diffraction characterization proved that β-cyclodextrin (β-CD) was successfully grafted with sodium alginate. After successful immobilization, yield of enzyme was found 91.5%, pH and temperature optima were increased, 6.0 to 7.0 and 50 °C to 55 °C respectively. Immobilized mannanase was able to reuse 15 times and retained its 70% activity, meanwhile the immobilized enzyme showed 60% activity after 30 days of storage at 4 °C. Immobilization also increased the thermostability and half-life of the enzyme when compared to the free mannanase. During the comparison of adsorption isotherm and kinetic models, Langmuir isotherm and pseudo-first order kinetics were observed to be the best fit model for the confirmation of immobilization., Competing Interests: Declaration of competing interest The authors with listed names declare no conflict of interest to disclose., (Copyright © 2019 Elsevier B.V. All rights reserved.)

The bottom-up approach of supramolecular polymerization is an effective synthetic method for functional organic nanostructures. However, the uncontrolled growth and polydisperse structural outcome often lead to low functional efficiency. Thus, precise control over the structural characteristics of supramolecular polymers is the current scientific hurdle. Research so far has tended to focus on systems with inherent kinetic control by the presence of metastable state monomers either through conformational molecular design or by exploring pathway complexity. The need of the hour is to create generic strategies for dormant states of monomers that can be extended to different molecules and various structural organizations and dimensions. Here we venture to demonstrate chemical reaction-driven cooperative supramolecular polymerization as an alternative strategy for the controlled synthesis of organic two-dimensional nanostructures. In our approach, the dynamic imine bond is exploited to convert a non-assembling dormant monomer to an activated amphiphilic structure in a kinetically controlled manner. The chemical reaction governed retarded nucleation-elongation growth provides control over dispersity and size., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

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.

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.

Temporal regulation of mass transport across the membrane is a vital feature of biological systems. Such regulatory mechanisms rely on complex biochemical reaction networks, often operating far from equilibrium. Herein, we demonstrate biochemical reaction mediated temporal regulation of mass transport in nanochannels of mesoporous silica sphere. The rationally designed nanochannels with pH responsive electrostatic gating are fabricated through a hetero-functionalization approach utilizing propylamine and carboxylic acid moieties. At basic pH, cationic small molecules can diffuse into the nanochannels which release back to the solution at acidic pH. The transient ion transport is temporally controlled using a base as fuel along with esterase enzyme as the mediator. The slow enzymatic hydrolysis of a dormant deactivator (ethyl acetate) determines the lifetime of transient encapsulated state, which can be programmed easily by modulating the enzymatic activity of esterase. This system represents a unique approach to create autonomous artificial cellular models., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Temporal control over self-assembly process is a desirable trait in the quest towards adaptable and controllable materials. The ability to devise synthetic ways to control the growth, as well as decay of materials has long been a property which only the biological systems could perform seamlessly. A common synthetic strategy which works on the biological principles such as chemical fuel-driven control over temporal self-assembly profile has not been completely realized synthetically. Here we show, we filled this dearth by showing that a chemical fuel driven self-assembling system can not only be grown in a controlled manner, but it can also result in precise control over the assembly and disassembly kinetics. Herein, we elaborate strategies which clearly show that once a chemical fuel driven self-assembly is established it can be made receptive to multiple molecular cues such that the inherent growth and decay characteristics are programmed into the ensemble.

Thriving natural systems precisely regulate their complex chemical organizations in space and time by recruitment of a complex network of fuel-driven, kinetically controlled, out-of-equilibrium transformations. Indeed this provides an active, adaptive and autonomous smart actions & functions. In contrast, synthetic systems exhibit simpler behavior owing to thermodynamically driven supramolecular polymerization with no temporal modulation of spatial organization. Stimulated by an outstanding control that nature demonstrates, a drive towards artificial out-of-equilibrium systems with the ambition to program activation and duration of structural transformations has emerged. To realize this vision, overwhelming efforts across the globe have been initiated to design temporally programmed synthetic supramolecular polymers. In an attempt to contribute to this trending field, our supramolecular chemistry group has thoroughly investigated a structure-property relationship that determines the mechanism of supramolecular polymerization. Exploiting these mechanistic insights, along with a bio-inspired fuel-driven enzyme mediated approach, we further attempted to program supramolecular polymers in both structural and temporal regimes. We believe, nature is the inspiration to the current era challenges and it also provides with the solution, a fuel-driven approach to address these. In this account, we shall discuss the efforts made by our group to build generic concept to create temporally programmable supramolecular polymers., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

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.

Chirality-driven self-sorting is envisaged to efficiently control functional properties in supramolecular materials. However, the challenge arises because of a lack of analytical methods to directly monitor the enantioselectivity of the resulting supramolecular assemblies. Presented herein are two fluorescent core-substituted naphthalene-diimide-based donor and acceptor molecules with minimal structural mismatch and they comprise strong self-recognizing chiral motifs to determine the self-sorting process. As a consequence, stereoselective supramolecular polymerization with an unprecedented chirality control over energy transfer has been achieved. This chirality-controlled energy transfer has been further exploited as an efficient probe to visualize microscopically the chirality driven self-sorting., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The spatial and temporal control of self-assemblies is the latest scientific hurdle in supramolecular chemistry which is inspired by the functioning of biological systems fueled by chemical signals. In this study, we work towards alleviating this scenario by employing a unique amphiphilic foldamer that operates under the effect of a chemical fuel. The conformational changes in the foldamer amplify into observable morphological changes in its amphiphilic assembly that are controlled by external molecular cues (fuel). We take advantage of this redox responsive foldamer to affect its conformation in a temporal manner by an enzymatic pathway. The temporal characteristics of the transient conformation/assembly can be modulated by varying the concentrations of the fuel and enzyme. We believe that such a design strategy can have positive consequences in designing molecular and supramolecular systems for future active, adaptive and autonomous materials.

Synthetic manifestations of supramolecular chirality have extensively drawn inspiration from naturally occurring systems. Even though in biological systems conformational changes are dissipative, synthetic systems that change conformation under non-equilibrium conditions have still not been established. Herein, we attempt to alleviate this scenario by reporting a synthetic supramolecular system that undergoes temporal changes in its helical conformation as an active system at the expense of a biologically relevant chemical fuel, ATP. Use of enzymes working in tandem provides transient and switchable helices with modular lifetime and stereomutation rates., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Background: The transition metal oxide nanoparticles are in focus for their anti-cancer potential. In this study we have synthesized and characterized CuO, NiO and Fe2O3 nanoparticles and, investigated their cytotoxic potential in the heterogeneous tumour microenvironment., Methods: Nanoparticles were synthesized by aqueous precipitation method and characterized with UV-Visible spectrophotometer, Fourier transform infrared spectroscopy (FTIR), Scanning electron microscopy (SEM) and X-ray diffraction (XRD). Cell viability of lung cancer cells (A549) grown in normoxia (18%O2) and hypoxia (1%O2) was determined for all nanoparticles. The mechanism of cell death was assessed by nuclear morphological analysis, flow cytometry analysis and western blotting. Generation of intracellular ROS in treated cells and its contribution to cell viability was determined., Results: The synthesized metal oxide nanoparticles were successfully characterized with SEM, spectroscopy and X-ray diffraction patterns. Cell viability of lung cancer cells was compromised in both normoxia and hypoxia. ROS generation was shown to contribute to cellular toxicity in CuO, but not NiO and Fe2O3., Conclusion: We have shown the therapeutic potential of CuO, NiO and Fe2O3 nanoparticles in non small cell lung cancer cells cultured in hypoxia, a relevant feature of solid tumors along with normoxia. The newly synthesized nanoparticles showed efficacy in both conditions., General Significance: Hypoxia drives metabolic alterations and epigenetic modifications in the tumor microenvironment. By using conditions that mimic tumour microenvironment, this study expands the possibility of using metal oxide nanoparticles as a therapeutic agent for lung cancer treatment., (Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.)