seminar_Professor Olli Ikkala_Multiscale Biofabrication Towards System 'Engineering' Biology

Multiscale Biofabrication Towards System ‘Engineering’ Biology

Presenter: Prof. Olli Ikkala
Professor of Bioengineering, Aalto University (Finland)

Prof. Olli Ikkala is a distinguished researcher at the Department of Applied Physics, Aalto University in the Helsinki metropolitan area. Originally trained in quantum physics, he spent a decade in industry working on supramolecular self-assemblies of electrically conducting polymers, tailoring them for real-world applications. His current research focuses on bioinspiration—using nature as a guide to create novel static and dynamic properties in soft matter. His work spans hierarchical self-assemblies, nacre-mimetic materials, functional nanocelluloses, and stimulus-responsive soft systems that mimic behavioral learning like Pavlovian conditioning, habituation, and sensitization.

Context: Bioinspired Materials

Nature excels at engineering through self-assembly, hierarchy, adaptability, and multifunctionality. Inspired by this, researchers seek to mimic or harness these traits in synthetic materials.

Key characteristics:

• Hierarchical self-assembly
• High strength and toughness
• Superhydrophobicity and dirt repellency

Selected Examples

1. Photonic fluids with Bragg reflections of colloids

   • Goal: Achieve periodicities in the optical wavelength range
   • Example: Fluorohectorite clays with ideal delamination behavior

2. Photonic fluids based on polymer Bragg reflection

3. Cellulose nanocrystal–based structural colors

4. Structural whiteness

   • Disorder and scattering create whiteness without Bragg reflection

5. Nacre-mimetic composites

   • Transition from thin films to bulk materials with exceptional strength

6. Roll-to-roll processing

   • Industrially scalable production of strong nacre-mimetic films

7. Superhydrophobic surfaces

   • Inspired by lotus leaves and water striders

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But Life is Dynamic…

Biological systems are not just strong or functional—they are dynamic, adaptive, and intelligent. The next frontier in materials science is to engineer materials that embody these living characteristics.

Key Traits of Living Materials:

1. Out-of-equilibrium, dissipative dynamics
2. Behavioral learning
3. Plasticity
4. Adaptation
5. Responsiveness
6. Homeostasis

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Towards Adaptive and Learning Materials

Stimuli-Responsive & Shape-Memory Materials

Current materials can respond to:

• Remote stimuli: Light, magnetic field, temperature
• Local stimuli: Electric field, pH, chemical reactions

However, these responses are typically pre-programmed—they don’t evolve or learn new behaviors.

Types of responses:

• Volumetric change
• Shape deformation
• Optical/electrical property shifts

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What About Learning?

In biology, even simple organisms modify their behavior via learning mechanisms:

• Habituation
• Sensitization
• Classical (Pavlovian) conditioning

Learning in animals (and even plants!) involves perception, memory, reflex, and motor control—immensely complex.

Example: Classical Conditioning in Liquid Crystalline Elastomers

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Ants as Inspiration!

Nature’s decentralized intelligence offers new directions. Ants, for example, display:

• Magnetic field sensing
• Short-range communication via pheromones
• Collective intelligence (e.g., self-assembled bridges)

Hypothesis:

Can soft ferromagnetic particles be designed to:

• Enable local dipolar interactions
• Be controlled by a tunable global magnetic field

From one pillar to many—materials that self-assemble, disassemble, and respond adaptively.

Bistable Systems: Magnetic-Field Responsive Electronics

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Training Materials for Increased Sensitivity

Imagine materials that train themselves to become more responsive over time.

The ultimate goal?
“Materials intelligence”—whether centralized or distributed, like in ant colonies.

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Acknowledgments

Funded by:

• European Research Council (ERC)
• Academy of Finland
• Alexander von Humboldt Foundation (Germany)

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