Orlin Velev

This proposal will consider novel classes of organized nanochannel biomolecular nanomaterials for understanding the design principles of efficient organized gel-like adaptive materials with enhanced porosity dimension and topological control, materials and energy transport, chiral biomolecules selection and storage/release, and prospective chiral biocatalytic templates. The team will synthesize, design, and study biomolecular magnetic organic frameworks (BiMOFs) based upon biologically encoded peptides with metal-binding terminal groups for coordination with magnetic ions/clusters.

Besides native whey protein-based ingredients, pre-denatured whey protein ingredients have also been commercialized. In general, spherical/microgel whey protein aggregates are dominated in the mentioned commercial ingredients. These spherical assemblies may be applied in various food matrices as fat replacer and for improving heat stability and reducing viscosity of high protein food products. Besides the spherical/isotropic protein assemblies, the anisotropic structures of protein aggregates have been recognized as functional building blocks of food structures. For instance, whey protein fibers are highly surface-active materials. This type of protein assembly may result a high mechanical strength film at the oil-water interface therefore, the stabilities of both emulsion droplets and the encapsulated marco-/micro-nutrients may be dramatically increased in the gastrointestinal tract during digestion. Moreover, whey protein fibers may be used to form nanotubes which are desired carriers of sensitive vaccines and drug molecules. Whey protein fibrils (WPF) are more functional than the spherical protein assemblies, however, no commercial ingredient of WPF is available in the market yet. This is due to the fabrication of whey protein fibers requires high energy input and longer time. For instance, the WPF fabrication requires heating 2.8 wt% WPI for 20 h at 90 ����C and at pH 2. In the proposed project, a novel scalable and economical method will be developed for manufacturing WPF.

The objective of this proposal is to realize a circular economic system for manufacturing of soft electronics where a coordinated set of sustainable manufacturing processes and a select group of novel biodegradable and reusable materials are seamlessly integrated. It is anticipated that all components of the device can be either biodegraded or recycled/reused, and the project will explore different end-of-life pathways from both technical, economic, and environmental perspectives (e.g., through life cycle assessment and techno-economic analysis). Our team has faculty members from mechanical engineering, chemistry, chemical engineering, Industrial Engineering, and sustainable engineering, allowing us to propose a hybrid approach from material design/synthesis all the way to device manufacturing.

The daunting challenges associated with capturing and recycling microplastic particles are that common processes for particle capture such as filtration are cost-prohibitive and that energy-efficient approaches to depolymerization do not yet exist. We propose innovative solutions to both challenges. Guided by multi-scale computational and machine-learning methodologies (Hall and You), our team aims to develop innovative strategies that use active colloidal systems that recognize and remove microplastic particles from water (Velev and Abbott), and then subsequently transform the captured plastics into valuable chemical feed stocks via microbial systems optimized by directed evolution (Crook). Through this approach, our team will advance E3P goals of enabling processes that eliminate plastic waste (Thrust 3) and permit depolymerization of polymers (Thrust 2). Our approach fuses a series of ambitious efforts, including (i) the computational design of peptides that will be optimized to recognize specific polymeric surfaces, (ii) the design of next-generation ����������������active��������������� particle microcleaners that have fibrillar coronas and move autonomously in aqueous environments, thus enabling efficient capture of microplastics, and (iii) data-driven optimization of efficient microbial biocatalysts for depolymerization, achieved by bioprospecting of natural plastic degraders, metabolic engineering of rapidly-growing marine bacteria, and high-throughput directed evolution. To intensify this integrated capture and depolymerization process, we will also develop a new class of liquid crystal-based sensors (integrating the designer peptides mentioned above) that will monitor process conditions and increase its throughput using modern artificial intelligence and deep learning algorithms. This comprehensive approach will build the basis of a circular plastics economy.

The directed assembly of reconfigurable and "active" structures from particles is an emerging field of intense scientific interest. The goal of this project is to establish the principles of self-organization underlying the assembly of particles with complex shapes, asymmetric interactions and the ability to self-propel in a time-dependent fashion. Two types of cube-shaped magnetically-responsive metal-dielectric particles will be used: microcubes with a metallic coating on one side and those with a metallic coating on two (opposite) sides. Application of a magnetic field induces a dipole within the coating(s), causing the particles to align with the field when it is turned on and to interact via directional dipole-dipole interactions when the field is turned off. Application of an a-c electric field causes the particles to self-propel in one direction at low frequencies and in the other direction at high frequencies. This combination of designed shape, directional interactions, ability to self-propel and responsiveness to time-dependent magnetic and electric fields offers a rich design space to explore and exploit. The project will include three major objectives: (1) to establish the fundamental principles of interaction-driven assembly for the two types of microcubes in the presence and absence of a magnetic field, (2) to explore how adding in particle motility modifies the types of phases assembled by the microcubes and their properties, and (3) to use the responsive and reconfigurable assemblies made by these particles as the core for new types of materials with unusual properties for selected applications. This project will thus advance fundamental understanding of the fields of colloidal assembly and active matter, and will serve as a comprehensive test-bed for accelerating our ability to design the next generation of complex particle������������������based.

This proposal will develop new systems for practical DNA-based information storage systems.

The self-propelled particles are a new type of soft matter with extraordinary properties. One very promising way of making particles propel is powering them with an external field. The proposed project seeks to undertake a detailed experimental and theoretical study of the effects of symmetry breaking of self-propelled particles via geometry and metallic/semiconducting material coating combined with optical gated semiconductor material properties. Hence, an overall outcome is the development of dynamically switchable (both rotation and translation) of micro/nanomotors.

The goal of this project is to develop a class of sensors based entirely on soft materials including hydrogels, elastomers, and liquid metals. The appeal of this approach to sensing is that (1) the hydrogels are biocompatible and in principles can be interfaced with the skin, and (2) the materials are all soft and therefore can conform to the skin in a comfortable manner. The premise of the sensing arises from doping the gels with responsive molecules that can induce a detectable signal that can be integrated with other components being researched within the ASSIST program.

This project will develop a new toolbox of methods for efficient investigation of the colloidal interactions and biological stability of viruses in suspension and on surfaces. It will present two major advances that will be key to developing future Unilever products. First, it will apply the proven fundamentals of ����������������classical��������������� colloidal science to viral vectors interacting with surfactants, polyelectrolytes, biopolymers, and dedicated antivirals. This will allow systematic formulation of products that will destabilize and inactivate viruses as a major goal or added benefit. Second, the project will provide Unilever with a set of experimental techniques and virus surrogate models, that will allow the robust, inexpensive, and large-scale testing and verification of both immediate and long-term antivirus efficiency of new personal care products. These tools will include the already established DLS, TEM and electrophoretic scattering methods introduced by Velev group, as well as newly developed millifluidic cells for virus-surface studies. The systems that will be characterized include real SL1 and SL2 level viruses, virus-like particles (VLPs), and a new class of model surrogates that we call virus colloidal surrogates (VCSs). The results of this project will enable the development of much needed future consumer products that will clean and deactivate viruses based on a new level of fundamental understanding and an experimental toolbox for product antiviral efficiency characterization.

One of the next major challenges in the field of active particles is introducing an application, where active propulsion will provide unique functionality ������������������ and would justify the increased complexity and cost. This challenge has not been resolved to date. The present types of active particles are rather complicated, or require special medium for propulsion, which are difficult to transcribe in real world active systems. We propose a principle of osmotic propulsive motion that will enable us to make and demonstrate the simplest and possibly most efficient active particle system to date. The project will first introduce a new physical means of achieving self-propulsion in active particle systems. The ����������������superdiffusive paste��������������� made of such particles will have extraordinary properties in being able to quickly permeate any media with interconnected pores, rapidly infusing any crevice, pore, and cavity, due to the random directional motility of the particles. We have identified interdental channel disinfection as one application where the superdiffusive paste can make high-impact technology. We will seek to prepare superdiffusive paste loaded with disinfectant, which will be able to penetrate the complex inner channel network of teeth and kill all microbes concealed within this network. The evaluation of the efficiency and usability of the paste will be performed in collaboration with dental investigators at the University of Pennsylvania. Thus, this project will deliver new physical methods for active particle propulsion, basic understanding of the extraordinary properties of superdiffusive paste made of such particles, and will seek to prove the first highly effective application of active particle systems in real biomedical practice.