Membranes are the key structures to separate and spatially organize cellular systems. Their rich dynamics and transformations during the cell cycle are orchestrated by specific membrane‐targeted ...molecular machineries, many of which operate through energy dissipation. Likewise, man‐made light‐activated molecular rotary motors have previously shown drastic effects on cellular systems, but their physical roles on and within lipid membranes remain largely unexplored. Here, the impact of rotary motors on well‐defined biological membranes is systematically investigated. Notably, dramatic mechanical transformations are observed in these systems upon motor irradiation, indicative of motor‐induced membrane expansion. The influence of several factors on this phenomenon is systematically explored, such as motor concentration and membrane composition., Membrane fluidity is found to play a crucial role in motor‐induced deformations, while only minor contributions from local heating and singlet oxygen generation are observed. Most remarkably, the membrane area expansion under the influence of the motors continues as long as irradiation is maintained, and the system stays out‐of‐equilibrium. Overall, this research contributes to a comprehensive understanding of molecular motors interacting with biological membranes, elucidating the multifaceted factors that govern membrane responses and shape transitions in the presence of these remarkable molecular machines, thereby supporting their future applications in chemical biology.
Explore the nuanced relationship between light‐driven molecular motors and lipid membranes in this research. Delve into the continuous interplay, observing how these motors, akin to dynamic springs fueled by light, orchestrate subtle yet fascinating shape transitions in membranes. Observe how these out‐of‐equilibrium systems can modulate area expansion through their action in lipid membranes.
The design of stimuli-responsive systems in nanomedicine arises from the challenges associated with the unsolved needs of current molecular drug delivery. Here, we present a delivery system with high ...spatiotemporal control and tunable release profiles. The design is based on the combination of an hydrophobic synthetic molecular rotary motor and a PDMS-
-PMOXA diblock copolymer to create a responsive self-assembled system. The successful incorporation and selective activation by low-power visible light (λ = 430 nm, 6.9 mW) allowed to trigger the delivery of a fluorescent dye with high efficiencies (up to 75%). Moreover, we proved the ability to turn on and off the responsive behavior on demand over sequential cycles. Low concentrations of photoresponsive units (down to 1 mol% of molecular motor) are shown to effectively promote release. Our system was also tested under relevant physiological conditions using a lung cancer cell line and the encapsulation of an Food and Drug Administration (FDA)-approved drug. Similar levels of cell viability are observed compared to the free given drug showing the potential of our platform to deliver functional drugs on request with high efficiency. This work provides an important step for the application of synthetic molecular machines in the next generation of smart delivery systems.
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•Double and triple functionalization of oxindole-based molecular motors is possible retaining the desirable qualities of these type of molecular machines.•Establishing a push–pull ...system in oxindole-based molecular motors shifts the absorption maximum further into the visible region and increases their two-photon absorption cross section.•First time demonstration of an oxindole based molecular motor operated with near infra-red light.•Improved performances, visible light addressability, quantum yield of photoisomerization, of oxindole based molecular motors compared to previously reported.
Future applications of light-driven molecular motors in bio-based systems and soft materials require their operation with benign, low-energy light irradiation. Here we report four rotary molecular motors based on oxindole units which can be driven by near-infrared light. By installing an electron-withdrawing CN group on the oxindole lower half, in direct conjugation through the alkene axle to the electron-donating OMe substituent on the upper half, our design establishes a rigid push–pull system which red-shifts the absorption maximum further into the visible region. We also show that the induced nonlinearity to the system increases their two-photon absorption cross section, and the operation of oxindole based molecular motors with 800 nm light for the very first time. The motors prepared in this work show improved performance compared to previous oxindole based motors, e.g. visible light addressability up to 530 nm and 1.5-fold increase in quantum yields in both directions, whilst retaining their desirable qualities of easy synthesis and fast rotation speed.
Overcrowded alkene based molecular motors and switches constitute a unique class of photo-responsive systems due to their intrinsic chirality near the core C&z.dbd;C bond, making them highly suitable ...candidates for the construction of light-switchable dynamic systems,
i.e.
, for controlling molecular motion, modulation of material chiroptical properties and supramolecular assembly. However, the lack of general design principles, along with the challenging synthesis of these molecules, precludes full exploitation of their dynamic structures. Therefore, systematic investigations of the key parameters are crucial for the further development of these systems. Here we provide a facile alternative synthetic route, elucidate the influence of substituents on the photochemistry of overcrowded alkene-derived bistable chiroptical photoswitches, and show nearly quantitative bidirectional photoswitching. The established structure-property relationship constitutes a practical guideline for the design of these photochromes tailored to a specific application.
Overcrowded alkene based bistable switches constitute a unique class of photo-responsive systems due to their intrinsic chirality near the core C&z.dbd;C bond, making them highly suitable candidates for the construction of light-switchable dynamic systems.
3‐Benzylidene‐indoline‐2‐ones play a prominent role in the pharmaceutical industry due to the diverse biomedical applications of oxindole heterocycles. Despite the extensive reports on their ...biological properties, these compounds have hardly been studied for their photochemical activity. Here, we present 3‐benzylidene‐indoline‐2‐ones as a promising class of photoswitches with high yields, robust photochemical switching with quantum yields reaching up to 50 % and potential for biological applications.
3‐Benzylidene‐indoline‐2‐ones are of great importance for the pharmaceutical industry. These compounds have been extensively reported for their biological properties, but have hardly been studied concerning their photochemical activity. Here, we present 3‐benzylidene‐indoline‐2‐ones as a promising class of photoswitches with high yields, robust photochemical switching, and quantum yields reaching up to 50 %.
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