Artificial Motors Research Articles

Polymer colloidal motors with photodynamic-regulated propulsion

Artificial colloidal motors capable of converting various external energy into mechanical motion, have emerged as attractive photosensitizer (PS) nanocarriers with good deliverability for photodynamic therapy. However, photoactivated 3O2-to-1O2 transformation as the most crucial energy transfer of the photodynamic process itself is still challenging to convert into autonomous transport. Herein, we report on PS-loaded thiophane-containing semiconducting conjugated polymer (SCP)-based polymer colloidal motors with asymmetric geometry for photodynamic-regulated propulsion in the liquid. The asymmetrical presence of the SCP phases within the colloidal motors would lead to significant differences in the 3O2-to-1O2 transformation and 1O2 release manners between asymmetrical polymer phases, spontaneously creating asymmetrical osmotic pressure gradients across the nanoparticles for powering the self-propelled motion under photodynamic regulation. This photoactivated energy-converting behavior can be also combined with the photothermal conversion of the SCP phases to create two energy gradients exerting diffusiophoretic/thermophoretic force on the colloidal motors for achieving multimode synergistic propulsion. This unique motile feature endows the light-driven PS nanocarriers with good permeability against various physiological barriers in the tumor microenvironment for enhancing antitumor efficacy, showing great potential in phototherapy.

Molecular robotic agents that survey molecular landscapes for information retrieval

DNA-based artificial motors have allowed the recapitulation of biological functions and the creation of new features. Here, we present a molecular robotic system that surveys molecular environments and reports spatial information in an autonomous and repeated manner. A group of molecular agents, termed ‘crawlers’, roam around and copy information from DNA-labeled targets, generating records that reflect their trajectories. Based on a mechanism that allows random crawling, we show that our system is capable of counting the number of subunits in example molecular complexes. Our system can also detect multivalent proximities by generating concatenated records from multiple local interactions. We demonstrate this capability by distinguishing colocalization patterns of three proteins inside fixed cells under different conditions. These mechanisms for examining molecular landscapes may serve as a basis towards creating large-scale detailed molecular interaction maps inside the cell with nanoscale resolution.

Motility of an autonomous protein-based artificial motor that operates via a burnt-bridge principle

Inspired by biology, great progress has been made in creating artificial molecular motors. However, the dream of harnessing proteins – the building blocks selected by nature – to design autonomous motors has so far remained elusive. Here we report the synthesis and characterization of the Lawnmower, an autonomous, protein-based artificial molecular motor comprised of a spherical hub decorated with proteases. Its “burnt-bridge” motion is directed by cleavage of a peptide lawn, promoting motion towards unvisited substrate. We find that Lawnmowers exhibit directional motion with average speeds of up to 80 nm/s, comparable to biological motors. By selectively patterning the peptide lawn on microfabricated tracks, we furthermore show that the Lawnmower is capable of track-guided motion. Our work opens an avenue towards nanotechnology applications of artificial protein motors.

Nanoscale feedback control of six degrees of freedom of a near-sphere

Manipulating the rotational as well as the translational degrees of freedom of rigid bodies has been a crucial ingredient in diverse areas, from optically controlled micro-robots, navigation, and precision measurements at macroscale to artificial and biological Brownian motors at nanoscale. Here, we demonstrate feedback cooling of all the angular motions of a near-spherical neutral nanoparticle with all the translational motions feedback-cooled to near the ground state. The occupation numbers of the three translational motions are 6 ± 1, 6 ± 1, and 0.69 ± 0.18. A tight, anisotropic optical confinement allows us to clearly observe three angular oscillations and to identify the ratio of two radii to the longest radius with a precision of 0.08 %. We develop a thermometry for three angular oscillations and realize feedback cooling of them to temperatures of lower than 0.03 K by electrically controlling the electric dipole moment of the nanoparticle.

Mechanochemical active ratchet

Self-propelled nanoparticles moving through liquids offer the possibility of creating advanced applications where such nanoswimmers can operate as artificial molecular-sized motors. Achieving control over the motion of nanoswimmers is a crucial aspect for their reliable functioning. While the directionality of micron-sized swimmers can be controlled with great precision, steering nano-sized active particles poses a real challenge. One of the reasons is the existence of large fluctuations of active velocity at the nanoscale. Here, we describe a mechanism that, in the presence of a ratchet potential, transforms these fluctuations into a net current of active nanoparticles. We demonstrate the effect using a generic model of self-propulsion powered by chemical reactions. The net motion along the easy direction of the ratchet potential arises from the coupling of chemical and mechanical processes and is triggered by a constant, transverse to the ratchet, force. The current magnitude sensitively depends on the amplitude and the periodicity of the ratchet potential and the strength of the transverse force. Our results highlight the importance of thermodynamically consistent modeling of chemical reactions in active matter at the nanoscale and suggest new ways of controlling dynamics in such systems.

Towards engineering artificial kinesin-14 motors with plus-end-directed processivity.

Kinesins are motor proteins that utilize the chemical energy of ATP hydrolysis to generate movement and force inside cells on the microtubule filaments to play important roles in a variety of essential intracellular processes. Kinesin-14s are a subset of kinesins with C-terminal motor domains and commonly exhibit minus-end-directed motility on the microtubule. Our previous work revealed that KlpA, a kinesin-14 motor from the filamentous fungus Aspergillus nidulans, uniquely exhibits processive plus-end-directed motility on single microtubules as individual homodimers. We hypothesized that KlpA achieves plus-end-directed motility on a single microtubule by adopting a strained cis-configuration whereby the N-terminal tail and the C-terminal motor domains simultaneously bind to the same microtubule. To test this hypothesis, we combined bioinformatic analysis and in vitro single-molecule fluorescence microscopy to search for additional kinesin-14s that exhibit similar plus-end-directed motility as KlpA. We found that AnKinesin-14 from Aspergillus niger has a similar coiled-coil profile as that of KlpA and exhibits processive motility towards the microtubule plus ends (unpublished results). Additionally, we engineered a chimera that replaces the C-terminal motor domains of AnKinesin-14 with those of Ncd (a nonprecessive minus-end-directed kinesin-14) and retains the coiled-coil profile of AnKinesin-14. Our single-molecule motility experiments showed that the chimera moves processively on the microtubule towards the plus ends. Collectively, our findings not only provide strong support of our previous hypothesis for the plus-end-directed motility of KlpA but also lay out a conceptual framework for how to engineer artificial kinesin motors with desired directionality using a cut-and-paste approach.

AI-VI DEFECT DETECTION

Real-time object detection and dimensioning are an important aspect from an industrial point of view. This study presents an augmented technique for detecting objects and computing their real-time measurements from a video device such as a webcam. We have suggested an object measurement technique in real-time using AI and ML. There are not many real-time object measurement models and this prototype can be used enormously further. This is an essential topic of computer vision problems. As stated, this project presents a technique for computing the measurements in real-time from images. To explain it’s working it basically uses a webcam and a white paper background to detect the object. After detecting the object, displays it dimensions in specified measuring units at real time. AI –VI (Artificial Intelligence and Visual Inspection) Defect Detection Solution is a system which will classify the springs automatically through artificial Intelligence, camera and motors. It will detect if there is any defect in the spring through webcam. If the defect is detected then it will segregate into Defected part otherwise it will consider it as good part.

Paclitaxel-conjugated phenylboronic acid-enriched catalytic robots as smart drug delivery systems

Artificial motors (robots) that are inspired by natural motors have captivated much attention with their attractive performances and special features. These miniaturized nano/micromotors have succeeded many important tasks in different fields including (bio)sensing, cargo transport, cell isolation and trapping, nanosurgery, gene therapy, and drug delivery. Herein, paclitaxel (PTX)-conjugated robots consisted of poly(3-aminophenylboronic acid) outer layer, a platinum (Pt)-nickel (Ni) segment, and a Pt catalytic inner layer were constructed to demonstrate their effective use for smart drug delivery. These self-functionalized motors had effective and smooth autonomous movement at velocities of 44 ± 9 μm/s and 34 ± 4 μm/s after 6 and 12 h of drug incubation steps. Fabrication of these motors was relied on electrochemical protocols, and the drug loading process was carried out by the interaction of the antitumor agent with the outer polymeric layer of the robots. Targeted delivery of the drug was achieved by the controlled driven of the robots toward human breast cancer cell line via induced Near-Infrared irradiation (NIR). pH dependency of the system was also demonstrated at acidic pH values. It was shown that the near-infrared irradiation increased the efficiency of the drug release through the polymeric robots. Polymeric robots showed promising viability results by using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide tetrazolium reduction (MTT) assays in order to signify potential and practical applications.

Enzyme-Free Liposome Active Motion via Asymmetrical Lipid Efflux

As a class of biocompatible, water-dispersed colloids, liposomes have found widespread applications ranging from food to drug delivery. Adding mobility to these colloids, i.e., liposome micromotors, represents an attractive approach to next-generation liposome carriers with enhanced functionality and effectiveness. Currently, it remains unclear as to the scope of material features useful for building liposome micromotors or how they may differ functionally from their inorganic/polymer counterparts. In this work, we demonstrate liposome active motion taking advantage of mainly a pair of intrinsic material properties associated with these assemblies: lipid phase separation and extraction. We show that global phase separation of ternary lipid systems (such as DPPC/DOPC/cholesterol) within individual liposomes yields stable Janus particles with two distinctive liquid domains. While these anisotropic liposomes undergo pure Brownian diffusion in water, similar to their homogeneous analogues, adding extracting agents, cyclodextrins, to the system triggers asymmetrical cholesterol efflux about the liposomes, setting the latter into active motion. We present detailed analyses of liposome movement and cholesterol extraction kinetics to establish their correlation. We explore various experimental parameters as well as mechanistic details to account for such motion. Our results highlight the rich possibility to hierarchically design lipid-based artificial motors, from individual lipids, to their organization, surface chemistry, and interfacial mechanics.

Machining Process Analysis for Machine Tool Selection Based on Form-Shaping Motions Using Statistical Analysis

: Productivity, cost of equipment and Ability to provide satisfactory service and when selecting machine tools Important to consider are factors. Machine tool selection is one of many manufacturing companies It is an important decision-making process. Improperly selected Machinery as a whole of production system reduce efficiency. speed of production, Quality, cost and efficiency will be used Lathes, Drilling Machines, Shaping Machines, planning machines, drilling machines, milling machines. Machine tools are also known as "work machines". They are various machines and Manufacture of processing equipment Machines to do. They are fully mechanical play an important role in the development of the industry, Depends on the type of machine tool. So, they are the mother of machines are called Machine tool Frictional materials in technology, Casting manufacturing, transmission, electrical equipment, including system integration etc. Conversely, machine tools are consumers Electronics, Automobile Industry, Mechanical Manufacturing, Electrical Equipment, Railway locomotives, Shipbuilding Industry, Defense Industry, Aerospace Industry Includes. and others occupations. A machine is a and to use forces to perform action Power to control movement A physical system that uses This term usually refers to artificial devices Engines or motors Used for, etc. But like molecular machines Also applied to natural biological macromolecules.

Fuel-Powered DNA Nanomachines for Biosensing and Cancer Therapy.

Inspired by biological motors, various artificial nanomachines and DNA motors have been fabricated to manipulate their motion on the nanometer scale, due to the high predictability and programmability of Watson-Crick base pairing. Among them, a fuel-powered DNA nanomachine is essentially a toehold-mediated strand exchange reaction and its driving force mainly comes from the hybridization of fuel DNA. It can be initiated by an input strand and automatically operate with the assistance of fuel DNA, realizing input strand recycle and signal amplification. Meanwhile, it is used as a carrier to load various drugs, such as Dox, siRNA and photosensitizers. Due to its excellent cellular penetrability and biocompatibility, fuel-powered DNA nanomachine usually enables operation inside living systems to execute all kinds of specific tasks according to the well-designed DNA strand displacement reaction, such as biomarker imaging, DNA computing and cancer theranostic applications. Therefore, as a catalytic amplification strategy and intelligent drug release platform, fuel-powered DNA nanomachine has attracted widespread attention in biosensors and cancer therapy. Hence, we present a Review on the design mechanism of fuel-powered DNA nanomachines and recent research advances in bioimaging and cancer therapy. It is hoped that this Review will provide the constructive direction for the design of fuel-powered DNA nanomachines and their applications in biological analysis and cancer treatment.

Through the Eyes of Creators: Observing Artificial Molecular Motors.

Inspired by molecular motors in biology, there has been significant progress in building artificial molecular motors, using a number of quite distinct approaches. As the constructs become more sophisticated, there is also an increasing need to directly observe the motion of artificial motors at the nanoscale and to characterize their performance. Here, we review the most used methods that tackle those tasks. We aim to help experimentalists with an overview of the available tools used for different types of synthetic motors and to choose the method most suited for the size of a motor and the desired measurements, such as the generated force or distances in the moving system. Furthermore, for many envisioned applications of synthetic motors, it will be a requirement to guide and control directed motions. We therefore also provide a perspective on how motors can be observed on structures that allow for directional guidance, such as nanowires and microchannels. Thus, this Review facilitates the future research on synthetic molecular motors, where observations at a single-motor level and a detailed characterization of motion will promote applications.

A synthetic tubular molecular transport system

Creating artificial macromolecular transport systems that can support the movement of molecules along defined routes is a key goal of nanotechnology. Here, we report the bottom-up construction of a macromolecular transport system in which molecular pistons diffusively move through micrometer-long, hollow filaments. The pistons can cover micrometer distances in fractions of seconds. We build the system using multi-layer DNA origami and analyze the structures of the components using transmission electron microscopy. We study the motion of the pistons along the tubes using single-molecule fluorescence microscopy and perform Langevin simulations to reveal details of the free energy surface that directs the motions of the pistons. The tubular transport system achieves diffusivities and displacement ranges known from natural molecular motors and realizes mobility improvements over five orders of magnitude compared to previous artificial random walker designs. Electric fields can also be employed to actively pull the pistons along the filaments, thereby realizing a nanoscale electric rail system. Our system presents a platform for artificial motors that move autonomously driven by chemical fuels and for performing nanotribology studies, and it could form a basis for future molecular transportation networks.

Five-Site Model for Brownian Dynamics Simulations of a Molecular Walker in Three Dimensions.

Motor proteins play an important role in many biological processes and have inspired the development of synthetic analogues. Molecular walkers, such as kinesin, dynein, and myosin V, fulfill a diverse set of functions including transporting cargo along tracks, pulling molecules through membranes, and deforming fibers. The complexity of molecular motors and their environment makes it difficult to model the detailed dynamics of molecular walkers over long time scales. In this work, we present a simple, three-dimensional model for a molecular walker on a bead-spring substrate. The walker is represented by five spherically symmetric particles that interact through common intermolecular potentials and can be simulated efficiently in Brownian dynamics simulations. The movement of motor protein walkers entails energy conversion through ATP hydrolysis while artificial motors typically rely on a local conversion of energy supplied through external fields. We model energy conversion through rate equations for mechanochemical states that couple positional and chemical degrees of freedom and determine the walker conformation through interaction potential parameters. We perform Brownian dynamics simulations for two scenarios: In the first, the model walker transports cargo by walking on a substrate whose ends are fixed. In the second, a tethered motor pulls a mobile substrate chain against a variable force. We measure relative displacements and determine the effects of cargo size and retarding force on the efficiency of the walker. We find that, while the efficiency of our model walker is less than for the biological system, our simulations reproduce trends observed in single-molecule experiments on kinesin. In addition, the model and simulation method presented here can be readily adapted to biological and synthetic systems with multiple walkers.

Optogenetic manipulation of cellular communication using engineered myosin motors.

Cells achieve highly efficient and accurate communication through cellular projections such as neurites and filopodia, yet there is a lack of genetically encoded tools that can selectively manipulate their composition and dynamics. Here, we present a versatile optogenetic toolbox of artificial multi-headed myosin motors that can move bidirectionally within long cellular extensions and allow for the selective transport of GFP-tagged cargo with light. Utilizing these engineered motors, we could transport bulky transmembrane receptors and organelles as well as actin remodelers to control the dynamics of both filopodia and neurites. Using an optimized in vivo imaging scheme, we further demonstrate that upon limb amputation in axolotls, a complex array of filopodial extensions is formed. We selectively modulated these filopodial extensions and showed that they re-establish a Sonic Hedgehog signaling gradient during regeneration. Considering the ubiquitous existence of actin-based extensions, this toolbox shows the potential to manipulate cellular communication with unprecedented accuracy.

Engineered myosins drive filopodial transport.

Engineered, light-inducible artificial myosin motors enable selective and direct manipulation of filopodial extensions and provide refined tools to control intracellular cargo transport in vivo.

Molecular motion and dielectric relaxation in chloroplumbate hybrid crystal

Molecular motion in crystals often suffer from severe limitations on their dynamic processes, and has received an extraordinary attention as artificial molecule motors and potential molecular dielectric materials. To investigated the relationship between the molecules motion in crystals and dielectric properties. Here, two hybrid crystals [1,3-bis(1-mim)C3]2[Pb4Cl12] (1) and [1,3-bis(1-mim)C3][Pb2Cl6] (2) (1,3-bis(1-mim)C3 = 1,3-bis(1-methylimidazolium)propane), which undergoes interesting dielectric relaxation and molecules motion were reported. Temperature-dependent single crystal structure shows the trans-cis transition of the carbon atoms and twisted rotation of the imidazolium ring were observed for 2. For 1, there exists thermal activating rapid motion for cation. Two compounds exhibit dielectric relaxation.The dielectric constant of 2 are much larger than 1 at the same frequency, which can be ascribed to the reorientational dynamics of guest water molecules and twisted rotation of the cation.

A Prospective Ultrafast Hemithioindigo Molecular Motor

AbstractThe maximum speed of light‐driven molecular motors is an important key‐property governing not only their overall performances but also many advanced functions. Currently, special emphasis lies on increasing the rate of unidirectional rotations to surpass natural systems and harness the full potential of artificial motors. Herein, we report a new molecular setup for a prospective light‐powered three‐step motor based on the hemithioindigo chromophore. Comprehensive quantum chemical treatment predicts a very low energy barrier for the only thermal ratcheting step in the unidirectional 360° rotation. Thus an ultrafast motion in the THz range could be possible with this motor at high light intensities and consequently a precise control of rotation speeds solely by light intensity variations could potentially be achieved. Experimental analyses using X‐ray crystallography and solution spectroscopy deliver first insights into the working mechanism and show that visible‐light photoswitching is feasible in both stable switching states. Additionally, significant alterations of the ground‐state energies can be induced by pH changes without hampering photoswitching capabilities.

Bacteriorhodopsin-Inspired Light-Driven Artificial Molecule Motors for Transmembrane Mass Transportation.

In nature, biological machines and motors can selectively transport cargoes across the lipid membranes to efficiently perform various physiological functions via ion channels or ion pumps. It is interesting and challengeable to develop artificial motors and machines of nanodimensions to controllably regulate mass transport in compartmentalized systems. In this work, we show a system of artificial molecular motors that uses light energy to perform transmembrane molecule transport through synthetical nanochannels. After functionalizing the polymer nanochannels with azobenzene derivatives, these nanomachines exhibit autonomous selective transport behavior over a long distance upon simultaneous irradiation with UV (365 nm) and visible (430 nm) light. With new strategies or suitable materials for directed molecular movement, such device can be regarded as a precursor of artificial light-driven molecular pumps.

Bacteriorhodopsin‐Inspired Light‐Driven Artificial Molecule Motors for Transmembrane Mass Transportation

AbstractIn nature, biological machines and motors can selectively transport cargoes across the lipid membranes to efficiently perform various physiological functions via ion channels or ion pumps. It is interesting and challengeable to develop artificial motors and machines of nanodimensions to controllably regulate mass transport in compartmentalized systems. In this work, we show a system of artificial molecular motors that uses light energy to perform transmembrane molecule transport through synthetical nanochannels. After functionalizing the polymer nanochannels with azobenzene derivatives, these nanomachines exhibit autonomous selective transport behavior over a long distance upon simultaneous irradiation with UV (365 nm) and visible (430 nm) light. With new strategies or suitable materials for directed molecular movement, such device can be regarded as a precursor of artificial light‐driven molecular pumps.