A High-Lift Micro-Aerial-Robot Powered by Low-Voltage and Long-Endurance Dielectric Elastomer Actuators

Development and Improvement of a Piezoelectrically Driven Miniature Robot

In this paper, we proposed a miniature quadrupedal piezoelectric robot with a mass of 1.8 g and a body length of 4.6 cm. The robot adopts a novel spatial parallel mechanism as its transmission. Each leg of the robot has two degrees of freedom (DOFs): swing and lift. The trajectory necessary for walking is achieved by the appropriate phasing of these two DOFs. A new manufacturing method for piezoelectric actuators was developed. During the stacking process, discrete patterned PZT pieces are used to avoid dielectric failure caused by laser cutting. Copper-clad FR-4 is used as the solder pad instead of copper foil, making the connection between the pad and the actuator more reliable. The lift powertrain of the robot was modeled and the link length of the powertrain was optimized based on the model. The maximum output force of each leg can reach 26 mN under optimized design parameters, which is 1.38 times the required force for successful walking. The frequency response of the powertrain was measured and fitted to the second-order system, which enabled increased leg amplitudes near the powertrain resonance of approximately 70 Hz with adjusted drive signals. The maximum speed of the robot without load reached 48.66 cm/s (10.58 body lengths per second) and the payload capacity can reach 5.5 g (3.05 times its mass) near the powertrain resonance.

In silico optimization of aligned fiber electrodes for dielectric elastomer actuators

Dielectric elastomer actuators (DEAs) exhibit fast actuation and high efficiencies, enabling applications in optics, wearable haptics, and insect-scale robotics. However, the non-uniformity and high sheet resistance of traditional soft electrodes based on nanomaterials limit the performance and operating frequency of the devices. In this work, we computationally investigate electrodes composed of arrays of stiff fiber electrodes. Aligning the fibers along one direction creates an electrode layer that exhibits zero stiffness in one direction and is predicted to possess high and uniform sheet resistance. A comprehensive parameter study of the fiber density and dielectric thickness reveals that the fiber density primary determines the electric field localization while the dielectric thickness primarily determines the unit cell stiffness. These trends identify an optimal condition for the actuation performance of the aligned electrode DEAs. This work demonstrates that deterministically designed electrodes composed of stiff materials could provide a new paradigm with the potential to surpass the performance of traditional soft planar electrodes.

Enhancing the Versatility and Performance of Soft Robotic Grippers, Hands, and Crawling Robots Through Three-Dimensional-Printed Multifunctional Buckling Joints

Soft robotic grippers and hands offer adaptability, lightweight construction, and enhanced safety in human-robot interactions. In this study, we introduce vacuum-actuated soft robotic finger joints to overcome their limitations in stiffness, response, and load-carrying capability. Our design-optimized through parametric design and three-dimensional (3D) printing-achieves high stiffness using vacuum pressure and a buckling mechanism for large bending angles (>90°) and rapid response times (0.24 s). We develop a theoretical model and nonlinear finite-element simulations to validate the experimental results and provide valuable insights into the underlying mechanics and visualization of the deformation and stress field. We showcase versatile applications of the buckling joints: a three-finger gripper with a large lifting ratio (∼96), a five-finger robotic hand capable of replicating human gestures and adeptly grasping objects of various characteristics in static and dynamic scenarios, and a planar-crawling robot carrying loads 30 times its weight at 0.89 body length per second (BL/s). In addition, a jellyfish-inspired robot crawls in circular pipes at 0.47 BL/s. By enhancing soft robotic grippers' functionality and performance, our study expands their applications and paves the way for innovation through 3D-printed multifunctional buckling joints.

Self-Healing Elastomers with Unprecedented Ultrahigh Strength, Superhigh Fracture Energy, Excellent Puncture Resistance, and Durability Based on Supramolecule Interlocking Networks Formed by Interlaced Hydrogen Bonds

Due to the multiple different properties in self-healing elastomers that are mutually exclusive based on the different and contradictory molecule chain structures, simultaneously achieving the ultrahigh mechanical performance and high durability of self-healing elastomers is a great challenge and the goal that has always been pursued. Herein, we report a novel strategy to fabricate a self-healing elastomer by introducing interlaced hydrogen bonds with superhigh binding energy. Distinguishing from the quadruple hydrogen bonds reported already, the interlaced hydrogen bond with a lower repulsive secondary interaction and higher binding energy is composed of two molecule units with different lengths and steric hindrance. Connected by the interlaced hydrogen bonds, a supramolecule interlocking network is formed to lock the polymer chains at room temperature, endowing the poly(urethane-urea) elastomer with an unprecedented ultrahigh strength (117.5 MPa, even higher than some plastics), the superhigh fracture energy (522.46 kJ m-2), and an excellent puncture resistance (puncture force reached 181.9 N). Moreover, the elastomers also exhibited excellent self-healing properties (healing efficiency up to 95.8%), high transparency (the average transmittance up to 91.0%), and good durability (including thermal decomposition resistance, thermal oxidation aging resistance, water resistance, and solvent resistance), providing a theoretical basis and technical reference in the development and broadening the application prospects of self-healing elastomers.

A Pneumatic Particle-Blocking Variable-Stiffness Actuator

In order to improve the stiffness of flexible robots, this paper proposes a variable-stiffness elastic actuator. The actuator integrates the working principles of a pneumatic drive, wedge structure, and particle blockage. The anti-tensile stiffness of the actuator is nonlinearly negatively correlated with the air pressure because of the structural and material properties. The anti-compressive stiffness and lateral stiffness increase nonlinearly as air pressure increases, being 3 and 121 times greater at 0.17 MPa compared to 0 MPa, respectively. Beyond 0.17 MPa, the two stiffnesses of the actuator experience incremental growth due to wedge resistance forces.

Functional PDMS Elastomers: Bulk Composites, Surface Engineering, and Precision Fabrication

Polydimethylsiloxane (PDMS)-the simplest and most common silicone compound-exemplifies the central characteristics of its class and has attracted tremendous research attention. The development of PDMS-based materials is a vivid reflection of the modern industry. In recent years, PDMS has stood out as the material of choice for various emerging technologies. The rapid improvement in bulk modification strategies and multifunctional surfaces has enabled a whole new generation of PDMS-based materials and devices, facilitating, and even transforming enormous applications, including flexible electronics, superwetting surfaces, soft actuators, wearable and implantable sensors, biomedicals, and autonomous robotics. This paper reviews the latest advances in the field of PDMS-based functional materials, with a focus on the added functionality and their use as programmable materials for smart devices. Recent breakthroughs regarding instant crosslinking and additive manufacturing are featured, and exciting opportunities for future research are highlighted. This review provides a quick entrance to this rapidly evolving field and will help guide the rational design of next-generation soft materials and devices.

Developments and Challenges of Miniature Piezoelectric Robots: A Review

Miniature robots have been widely studied and applied in the fields of search and rescue, reconnaissance, micromanipulation, and even the interior of the human body benefiting from their highlight features of small size, light weight, and agile movement. With the development of new smart materials, many functional actuating elements have been proposed to construct miniature robots. Compared with other actuating elements, piezoelectric actuating elements have the advantages of compact structure, high power density, fast response, high resolution, and no electromagnetic interference, which make them greatly suitable for actuating miniature robots, and capture the attentions and favor of numerous scholars. In this paper, a comprehensive review of recent developments in miniature piezoelectric robots (MPRs) is provided. The MPRs are classified and summarized in detail from three aspects of operating environment, structure of piezoelectric actuating element, and working principle. In addition, new manufacturing methods and piezoelectric materials in MPRs, as well as the application situations, are sorted out and outlined. Finally, the challenges and future trends of MPRs are evaluated and discussed. It is hoped that this review will be of great assistance for determining appropriate designs and guiding future developments of MPRs, and provide a destination board to the researchers interested in MPRs.

Light-driven dandelion-inspired microfliers

In nature, many plants have evolved diverse flight mechanisms to disperse seeds by wind and propagate their genetic information. Inspired by the flight mechanism of the dandelion seeds, we demonstrate light-driven dandelion-inspired microfliers based on ultralight and super-sensitive tubular-shaped bimorph soft actuator. Like dandelion seeds in nature, the falling velocity of the as-proposed microflier in air can be facilely controlled by tailoring the degree of deformation of the "pappus" under different light irradiations. Importantly, the resulting microflier is able to achieve a mid-air flight above a light source with a sustained flight time of ~8.9 s and a maximum flight height of ~350 mm thanks to the unique dandelion-like 3D structures. Unexpectedly, the resulting microflier is found to exhibit light-driven upward flight accompanied by autorotating motion, and the rotation mode can be customized in either a clockwise or counterclockwise direction by engineering the shape programmability of bimorph soft actuator films. The research disclosed herein can offer new insights into the development of untethered and energy-efficient artificial aerial vehicles that are of paramount significance for many applications from environmental monitoring and wireless communication to future solar sail and robotic spacecraft.

Engineering of Chain Rigidity and Hydrogen Bond Cross-Linking toward Ultra-Strong, Healable, Recyclable, and Water-Resistant Elastomers

High-performance elastomers have gained significant interest because of their wide applications in industry and our daily life. However, it remains a great challenge to fabricate elastomers simultaneously integrating ultra-high mechanical strength, toughness, and excellent healing and recycling capacities. In this study, ultra-strong, healable, and recyclable elastomers are fabricated by dynamically cross-linking copolymers composed of rigid polyimide (PI) segments and soft poly(urea-urethane) (PUU) segments with hydrogen bonds. The elastomers, which are denoted as PIPUU, have a record-high tensile strength of ≈142 MPa and an extremely high toughness of ≈527 MJ m^-3 . The structure of the PIPUU elastomer contains hydrogen-bond-cross-linked elastic matrix and homogenously dispersed rigid nanostructures. The rigid PI segments self-assemble to generate phase-separated nanostructures that serve as nanofillers to significantly strengthen the elastomers. Meanwhile, the elastic matrix is composed of soft PUU segments cross-linked with reversible hydrogen bonds, which largely enhance the strength and toughness of the elastomer. The dynamically cross-linked PIPUU elastomers can be healed and recycled to restore their original mechanical strength. Moreover, because of the excellent mechanical performance and the hydrophobic PI segments, the PIPUU elastomers are scratch-, puncture-, and water-resistant.

Uni- and Bidirectional Rotation and Speed Control in Chiral Photonic Micromotors Powered by Light

Liquid crystalline polymers are attractive materials for untethered miniature soft robots. When they contain azo dyes, they acquire light-responsive actuation properties. However, the manipulation of such photoresponsive polymers at the micrometer scale remains largely unexplored. Here, uni- and bidirectional rotation and speed control of polymerized azo-containing chiral liquid crystalline photonic microparticles powered by light is reported. The rotation of these polymer particles is first studied in an optical trap experimentally and theoretically. The micro-sized polymer particles respond to the handedness of a circularly polarized trapping laser due to their chirality and exhibit uni- and bidirectional rotation depending on their alignment within the optical tweezers. The attained optical torque causes the particles to spin with a rotation rate of several hertz. The angular speed can be controlled by small structural changes, induced by ultraviolet (UV) light absorption. After switching off the UV illumination, the particle recovers its rotation speed. The results provide evidence of uni- and bidirectional motion and speed control in light-responsive polymer particles and offer a new way to devise light-controlled rotary microengines at the micrometer scale.

Laser-assisted failure recovery for dielectric elastomer actuators in aerial robots

Insects maintain remarkable agility after incurring severe injuries or wounds. Although robots driven by rigid actuators have demonstrated agile locomotion and manipulation, most of them lack animal-like robustness against unexpected damage. Dielectric elastomer actuators (DEAs) are a class of muscle-like soft transducers that have enabled nimble aerial, terrestrial, and aquatic robotic locomotion comparable to that of rigid actuators. However, unlike muscles, DEAs suffer local dielectric breakdowns that often cause global device failure. These local defects severely limit DEA performance, lifetime, and size scalability. We developed DEAs that can endure more than 100 punctures while maintaining high bandwidth (>400 hertz) and power density (>700 watt per kilogram)-sufficient for supporting energetically expensive locomotion such as flight. We fabricated electroluminescent DEAs for visualizing electrode connectivity under actuator damage. When the DEA suffered severe dielectric breakdowns that caused device failure, we demonstrated a laser-assisted repair method for isolating the critical defects and recovering performance. These results culminate in an aerial robot that can endure critical actuator and wing damage while maintaining similar accuracy in hovering flight. Our work highlights that soft robotic systems can embody animal-like agility and resilience-a critical biomimetic capability for future robots to interact with challenging environments.

Multilayer Dielectric Elastomer with Reconfigurable Electrodes for Artificial Muscle

High-performance multilayer dielectric elastomer actuators (DEAs) are well-positioned to overcome the insufficient output force and energy density as artificial muscles. However, due to the fabrication process, the multilayer DEAs with nonmodifiable structures often suffer from the limitation of short lifespans and scalable preparation. Herein, reusable multilayer DEAs with the detachable and reconfigurable structure are fabricated. This is achieved by realizing scalable compliant electrodes using the continuous spatial confining forced network assembly (CSNA) method and combining the vacuum lamination (VL) approach to have good attachability and detachability with the VHB dielectric elastomer. The flexible roller-based CSNA method is used to prepare the large area compliant electrodes composed of α, ω-dihydroxy polydimethylsiloxane and electrically conductive nanoparticles. The fabricated electrodes can continuously work over 10 000 cycles at 40% strained stretching and maintain smooth surfaces to construct multilayer DEAs. Moreover, owing to the detachable configuration of the DEAs, the electrodes can also be recovered and reused for building new actuators. The lower limb assistive device is demonstrated by detachable multilayer spring roll DEAs, achieving approximately 3.1 degrees of flexion and extension movement of knee models under a voltage of 7 kV. The detachable and reconfigurable multilayer DEAs shed new light on the applications of wearable assistive devices.

Dandelion-Inspired, Wind-Dispersed Polymer-Assembly Controlled by Light

The rise of stimuli-responsive polymers has brought about a wealth of materials for small-scale, wirelessly controlled soft-bodied robots. Thinking beyond conventional robotic mobilities already demonstrated in synthetic systems, such as walking, swimming and jumping, flying in air by dispersal, gliding, or even hovering is a frontier yet to be explored by responsive materials. The demanding requirements for actuator's performance, lightweight, and effective aerodynamic design underlie the grand challenges. Here, a soft matter-based porous structure capable of wind-assisted dispersal and lift-off/landing action under the control of a light beam is reported. The design is inspired by the seed of dandelion, resembling several biomimetic features, i.e., high porosity, lightweight, and separated vortex ring generation under a steady wind flow. Superior to its natural counterparts, this artificial seed is equipped with a soft actuator made of light-responsive liquid crystalline elastomer, which induces reversible opening/closing actions of the bristles upon visible light excitation. This shape-morphing enables manual tuning of terminal velocity, drag coefficient, and wind threshold for dispersal. Optically controlled wind-assisted lift-off and landing actions, and a light-induced local accumulation in descending structures are demonstrated. The results offer novel approaches for wirelessly controlled, miniatured devices that can passively navigate over a large aerial space.

Crosslinking Methodology for Imidazole-Grafted Silicone Elastomers Allowing for Dielectric Elastomers Operated at Low Electrical Fields with High Strains

For improved actuation at low voltages of dielectric elastomers, a high dielectric permittivity has been targeted for several years but most successful methods then either increase the stiffness of the elastomer and/or introduce notable losses of both mechanical and dielectric nature. For polydimethylsiloxane (PDMS)-based elastomers, most high-permittivity moieties inhibit the sensitive platinum catalyst used in the addition curing scheme. In contrast to the classical addition curing pathway to prepare PDMS elastomers, here, an alternative strategy is reported to prepare PDMS elastomers via the crosslinking reaction between multifunctional imidazole-grafted PDMS with difunctional bis(1-ethylene-imidazole-3-ium) bromide ionic liquid (bis-IL). The prepared IL-elastomer entails uniformly dispersed IL and presents stable mechanical and dielectric properties due to the covalent nature of the crosslinking as opposed to previously reported physical mixing in of ILs. The relative permittivity was improved up to 200% by including the bis-IL in the elastomer, and Young's modulus was around 0.04 MPa. As a result of the excellent combination of properties, the dielectric actuator developed exhibits an area strain of 20% at 15 V/μm. The novel strategy to prepare PDMS elastomers provides a new paradigm for achieving high-performance dielectric elastomer actuators by a simple methodology.

Bio-inspired flapping wing robots with foldable or deformable wings: a review

Traditional flapping-wing robots (FWRs) obtain lift and thrust by relying on the passive deformation of their wings which cannot actively fold or deform. In contrast, flying creatures such as birds, bats, and insects can maneuver agilely through active folding or deforming their wings. Researchers have developed many bio-inspired foldable or deformable wings (FDWs) imitating the wings of flying creatures. The foldable wings refer to the wings like the creatures' wings that can fold in an orderly manner close to their bodies. Such wings have scattered feathers or distinct creases that can be stacked and folded to reduce the body envelope, which in nature is beneficial for these animals to prevent wing damage and ensure agility in crossing bushes. The deformable wings refer to the active deformation of the wings using active driving mechanisms and the passive deformation under the aerodynamic force, which functionally imitates the excellent hydrodynamic performance of the deformable body and wings of the creatures. However, the shape and external profile changes of deformable wings tend to be much smaller than that of folding wings. FDWs enable the FWRs to improve flight degree of flexibility, maneuverability, and efficiency and reduce flight energy consumption. However, FDWs still need to be studied, and a comprehensive review of the state-of-the-art progress of FDWs in FWR design is lacking. This paper analyzes the wing folding and deformation mechanisms of the creatures and reviews the latest progress of FWRs with FDWs. Furthermore, we summarize the current limitations and propose future directions in FDW design, which could help researchers to develop better FWRs for safe maneuvering in obstacle-dense environments.

Reconfigurable, Reversible, and Redefinable Deformation of GO Based on Quantum-Confined-Superfluidics Effect

Graphene oxide (GO) films with natural "quantum-confined-superfluidics" (QSF) channels for moisture actuation have emerged as a smart material for actuators and soft robots. However, programming the deformation of GO by engineering QSF nanochannels around 1 nm is extremely challenging. Herein, we report the reconfigurable, reversible, and redefinable deformation of GO under moisture actuation by tailoring QSF channels via moisture-assisted strain-induced wrinkling (MSW). The shape fixity ratio of a general GO film can reach ∼84% after the MSW process, and the shape recovery ratio is ∼83% at room temperature under moisture actuation. The flexible shaping and deformation abilites, as well as the self-healing property of GO make it possible to fabricate soft robots using GO. Besides, as a proof-of-concept, passive electronics and soft robots capable of crawling, turning, switching circuit, and automatic somersault are demonstrated. With unique shaping and deformation abilities, GO may bring great implications for future soft robotics.

Fluid Field Modulation in Mass Transfer for Efficient Photocatalysis

Mass transfer is an essential factor determining photocatalytic performance, which can be modulated by fluid field via manipulating the kinetic characteristics of photocatalysts and photocatalytic intermediates. Past decades have witnessed the efforts and achievements made in manipulating mass transfer based on photocatalyst structure and composition design, and thus, a critical survey that scrutinizes the recent progress in this topic is urgently necessitated. This review examines the basic principles of how mass transfer behavior impacts photocatalytic activity accompanying with the discussion on theoretical simulation calculation including fluid flow speed and pattern. Meanwhile, newly emerged viable photocatalytic micro/nanomotors with self-thermophoresis, self-diffusiophoresis, and bubble-propulsion mechanisms as well as magnet-actuated photocatalytic artificial cilia for facilitating mass transfer will be covered. Furthermore, their applications in photocatalytic hydrogen evolution, carbon dioxide reduction, organic pollution degradation, bacteria disinfection and so forth are scrutinized. Finally, a brief summary and future outlook are presented, providing a viable guideline to those working in photocatalysis, mass transfer, and other related fields.

Miniature Amphibious Robot Actuated by Rigid-Flexible Hybrid Vibration Modules

Amphibious robots can undertake various tasks in terrestrial and aquatic environments for their superior environmental compatibility. However, the existing amphibious robots usually utilize multi-locomotion systems with transmission mechanisms, leading to complex and bulky structures. Here, a miniature amphibious robot based on vibration-driven locomotion mechanism is developed. The robot has two unique rigid-flexible hybrid modules (RFH-modules), in which a soft foot and a flexible fin are arranged on a rigid leg to conduct vibrations from an eccentric motor to the environment. Then, it can run on ground with the soft foot adopting the friction locomotion mechanism and swim on water with the flexible fin utilizing the vibration-induced flow mechanism. The robot is untethered with a compact size of 75 × 95 × 21 mm³ and a small weight of 35 g owing to no transmission mechanism or joints. It realizes the maximum speed of 815 mm s^-1 on ground and 171 mm s^-1 on water. The robot, actuated by the RFH-modules based on vibration-driven locomotion mechanism, exhibits the merits of miniature structure and fast movements, indicating its great potential for applications in narrow amphibious environments.

Real time high voltage capacitance for rapid evaluation of dielectric elastomer actuators

Dielectric elastomer actuators (DEAs) are soft electromechanical transducers that have enabled robotic, haptic, and optical applications. Despite their advantages in high specific energy, large bandwidth, and simple fabrication, their widespread adoption is limited by poor long-term performance. While the mechanical work output has been studied extensively, the electrical energy input has rarely been characterized. Here we report a method to continuously monitor high voltage capacitance during DEA actuation to directly measure the electrical energy consumption. Our approach can track energy conversion efficiency, but also show changes in the device's properties in real-time. This unprecedented insight enables a novel way to study DEAs, evaluate degradation mechanisms, and correlate material structure to device performance. Moreover, it provides a data acquisition platform for data-driven optimization and prediction of long-term actuator performance. This work is a necessary step towards developing ultra-resilient DEAs and enabling a wide range of applications, from wearable devices to soft machines across different scales.

Design, Characterization, and Liftoff of an Insect-Scale Soft Robotic Dragonfly Powered by Dielectric Elastomer Actuators

Dragonflies are agile and efficient flyers that use two pairs of wings for demonstrating exquisite aerial maneuvers. Compared to two-winged insects such as bees or flies, dragonflies leverage forewing and hindwing interactions for achieving higher efficiency and net lift. Here we develop the first at-scale dragonfly-like robot and investigate the influence of flapping-wing kinematics on net lift force production. Our 317 mg robot is driven by two independent dielectric elastomer actuators that flap four wings at 350 Hz. We extract the robot flapping-wing kinematics using a high-speed camera, and further measure the robot lift forces at different operating frequencies, voltage amplitudes, and phases between the forewings and hindwings. Our robot achieves a maximum lift-to-weight ratio of 1.49, and its net lift force increases by 19% when the forewings and hindwings flap in-phase compared to out-of-phase flapping. These at-scale experiments demonstrate that forewing–hindwing interaction can significantly influence lift force production and aerodynamic efficiency of flapping-wing robots with passive wing pitch designs. Our results could further enable future experiments to achieve feedback-controlled flights.

Multistimulus-Responsive Graphene Oxide/Fe3O4/Starch Soft Actuators

Soft actuators that respond to external stimuli like moisture, magnetism, light, and temperature have received tremendous attention owing to their promising potential in many frontier applications, including smart switches, soft robots, sensors, and artificial muscles. However, most of the conventional actuators can only be triggered by a solo stimulus and demand advanced manufacturing techniques that utilize expensive, hazardous, and synthetic raw materials. Herein, we design and fabricate a multiple stimuli-responsive actuator using graphene oxide, Fe₃O₄ nanoparticles, and tapioca starch via a water evaporation-induced self-assembly method. The resultant hybrid actuator exhibits a bending speed of ∼72° s^-1 upon moisture exposure. Moreover, it can perform clockwise and counterclockwise rotations, linear motion, and magnetic object capture by regulating a magnetic field. As representative examples, the actuator is used to fabricate various smart devices such as smart curtains, biomimetic structures, and a smart gripper that undergo complex and consecutive motion under the influence of multiple stimuli.

Development, Statistical Optimization and Characterization of Fluvastatin Loaded Solid Lipid Nanoparticles: A 32 Factorial Design Approach

The purpose of the present research work was to design, optimize, and evaluate fluvastatin-loaded solid lipid nanoparticles (FLV-SLNPs) using 3² factorial design for enhancing the bioavailability. Fluvastatin has several disadvantages, including the low solubility and substantial first-pass metabolism resulting in a low (30%) bioavailability and a short elimination half-life. FLV-SLNPs were prepared using the nano-emulsion technique. For the optimization of the FLV-SLNPs, a total of nine formulations were prepared by varying two independent factors at three levels, using full factorial design. In this design, lipid (A) and surfactant (B) concentrations were chosen as independent factors, whereas entrapment efficiency (Y1) and in-vitro drug release (Y2) were selected as the dependent variables. Additionally, the prepared SLNPs were characterized for X-ray diffraction, Fourier transform-infrared spectroscopy, and differential scanning calorimetry. These studies revealed that there were no interactions between the drug and the selected excipients and the selected formulation components are compatible with the drug. Pharmacokinetic studies in rats confirmed significant improvement in AUC and MRT of SLNPs in comparison with the pure drug indicating the enhanced bioavailability of SLNPs. This study provides a proof-of-concept for the fact that SLNPs can be effectively developed via experimental factorial design, which requires relatively minimal experimentation.