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Algal polymer Hydrogels

Hydrogels are a network of crosslinked polymers that do not dissolve but can swell in water or respond to the environment.

They have a broad range of applications.

Hydrogel crosslinked without chemical reaction

Hydrogels are absorbent and can contain over 90% water. They possess a degree of flexibility due to their water content.

The personal lubricant (see earlier post) has led to investigation toward a range of other hydrogels.

Together with Peng Su we have been working toward production of hydrogels.

Early hydrogel investigation: tight matrix and unsatisfactory form. The crosslinking application was too aggressive.

Hydrogel properties:

  • both solid and liquid
  • high biocompatibility
  • can trap water
  • shrinks when dried

We have investigated with both homo-polymer (single) and co-polymer types. Certain types link without need for chemical crosslinking. Others we have chemically cross linked.

Applications:

  • Can be occupied by drug molecules for drug delivery
  • cell culture/engineering as extra-cellular/stem cell matrix
  • contact lens
  • wound dressing
  • can influence cell behaviour
  • water carrier/hydrophilic absorbent polymer
  • cancer treatment
  • drug delivery
  • bio-sensor – temperature, pH sensitive, glucose, antigens
  • skin generation
  • similar to natural tissue
  • cell entrapment – low toxicity, hydrogel beads
  • time release
  • transport properties
  • can be injected
  • food industry gel

Challenges;

  • non-adherent
  • low strength
  • difficult handling
Hydrogels chemically crosslinked in two stages

Initial experiments at CMDB showed that the delicate hydrogels polymers were disrupted by the addition of a crosslinking chemical. A two step, spray and dip method was developed by myself and Peng Su.

Reference:

Information pertaining to hydrogel properties and application.

https://www.slideshare.net/BobyKumar/hydrogels60929707

 

 

 

Diffraction; thinking with materials

This residency has been about thinking with models and materials to engage with larger questions of scientific practice, art practice and the environmental humanities.

Problems are thought through with materials as we handle them; become familiar with them and their potential properties; go about performative actions; think about developing certain qualities; carefully observe chemical reactions; change material properties for specific purposes.

1 Diffraction is a conceptual and material-semeiotic device that responds to the dilemma of how we think about complex matters in material ways; how we approach artistic and designer work so that it is not reduced to representational schemas or public communication of scientific facts; and how we can not merely reflect theories but participate in their production and transformative potential. 2 Diffractive models are real-world agents that are “interfering, bluring, bending and transforming the content under study”.

1 Parikka J, A recursice Web of Models: Studio Tomas Saraceno’s Working Objects 2020

2 Miyazaki S, How to talk about serious matters of complexity with models as agents: A speculative essay on artistic and design-based research, 2015

Designing stretchy alginate polymer

 

Plastics: Material Agents of Our Own Creation

Shimmying between forgotten debris and vibrant matter, the material assemblage made contact with Bennet and momentarily commanded her interest. (Otigen.N, p.285-286, 2020)

 

“With its interest in material stratification and the vicious haunting of things…Anthropocene literature provides a particularly rich site for studying material encounter as an everyday phenomenon…Following the understanding that this anthropogenic crisis has forced much of humankind to recognise we are now “being acted upon” by material agents of our own creation, things have come to matter in important ways…Amitav Ghosh* argues, that “inanimate things coming suddenly alive” is one of the uncanniest effects of the Anthropocene, this renewed awareness of the elements of agency and consciousness that humans share with other beings, and even perhaps the planet itself ”

Although found retrospectively to my work, Plastics Memento Mori, this paragraph from Nathaniel Otjen’s When things Hail: The Material Encounter In Anthropocene Literature,  supports the notion that we are subject to the agency of materials of our own creation.

Contrary to my use of the human figure to heighten attention to the agency of plastic waste (see earlier post), Otjen stresses that a phenomenological attentiveness on the behalf of humans as prerequisite for the encounter is believed by materialist thinkers to “obscure the agency of things and risk reinstalling the human figure as exceptional.”

This view could critique my Plastics Memento Mori work; implying that it requires correction. However, it is my view that within this work, the human figure is evidence of and critiques long-standing human hubris.

Nathaniel Otjen, Configurations, A Journal of Literature, Science, and Technology, When things Hail: The Material Encounter In Anthropocene Literature, Volume 28, Number 3, summer 2020.

*Amitav Ghosh, The Great Derangement: Climate Change and the Unthinkable, Chicago: University of Chicago Press, 2016

Guest speakers: Barry Murphy Seminar Series.

Ass Professor Julian Chalker speaking about sulfur polymers

During Lab meeting, we have been honored to receive Flinders University guest lecturers as part of the Barry Murphy Seminar Series. These guests have spoken about themes which pertain to our work with biopolymers.

Barry Murhpy Seminar Series.

Professor Youhong Tang, material scientist, lectured about;

  • His work with polymeric materials and nanocomposites especially on rubber and epoxy based resins.
  • Biosensors incorporating novel aggregation-induced emission materials (photoluminescent materials/SEM) to understand the stress evolution in polymer films. (Light emitting molecules reveal the mechanics of films under tensile stress)

Associate Professor Justin Chalker, lectured about the use of Sulfur in polymers.

Two different themes in sulfur chemistry.

  • Making probes to trap cysteine sulfenic acid (biomarker for oxidative stress and associated disease) on proteins and live cells: thus mapping cysteine sulfenic acid inside cell. Proteonomics analysis  has revealed 148 proteins previously unknown to produce oxidative stress.
  • Synthesis and applications of polymers made from 50% – 80% sulfur by mass; inspired by Jeff Pyun’s concept of “inverse vulcanisation”. These polymers can be designed toward; desired mechanical, thermal and optical properties; new concepts in repair and recycling of polymer materials. Applications for these polymers include environmental remediation (oil spill), controlled release fertilisers and mercury/cyanide free gold mining.

Chasing Chimeras: Bio-compatible marine algal bio-plastics

As part of this ANAT Synapse art/science residency with CMBD, and another art project (TBA), I have been examining the concept of a hybrid seaweed/mammalian biopolymer material.

This fits with my longstanding interest in the Chimera as hybrid entity.

Bio-compatible (mammalian cell compatible) polymers require certain attributes i.e. water resistance and open structure.

Experimenting with water resistance.

In earlier experiments I laminated natural seaweed biopolymer films with water resistant seaweed polymers to improve them.

After self-directed research, I added wax to polymers to further water resistance.

Initial drying showed marked shrinkage and cracking, however the material rehydrated well without excess swelling as with other polymer formulae.

I tweaked the formula and solved the cracking problem.

Below: Polymer before and after soaking in water, some swelling (less than regular polymer) and film remained strong.

Testing for water resistance: Biopolymer before soaking

 

Testing for water resistance: Biopolymer after soaking

As well as a film, I made simple hollow forms (vessels) to further test this bioplastic for water holding ability.

Vessel Prototype
Vessel prototype after drying: marked shrinkage

To reduce shrinkage, I experimented with polymer ratio to make denser films.

Denser polymer film: wax added

Testing biopolymer pH

In another direction this week with biocompatible polymers:

For optimal cross linking of bioplastic and biopolymer. Peng Su and I tested earlier formulations for pH.

Testing biopolymer pH

Freeze drying

To increase bio-compatibility (bio-compatible polymers can be used for bodily regeneration therapies e.g. cell culture), and breathability (for diverse use), the polymer was shocked using a variety of freezing methods.

Freezing polymers with liquid nitrogen
Freeze drying polymers

 

Plastics Memento Mori

Title: Plastics Memento Mori; Guilt.5 Artist: Niki Sperou

“Plastics memento Mori”, is a series of images which evoke the horror of the plastics problem and are a reminder of the inevitability of mortality. Memento mori works suggest that we take responsibility for our actions. Incorrect actions invariably lead to our demise. These images are grave, as critical issues demand serious responses.

Plastic fantastic? It’s interesting that good intentions can go awry. We may speculate about the future applications of novel technologies however they often have unforeseen implications. This ideology goes back to ancient times and is evidenced in Promethian myth. Fossil fuel plastics have saved lives. They were developed to alleviate pressure upon organic resources under threat due to high demand; whale products, tortoise shell, ivory, bone, sea shells, fur, leather and plant matter. In comparison to natural products, plastics are cheap, broadly available in a wide range of consumer products and are therefore economically democratic. Plastics, used extensively in the medical sciences continue to save lives. It must be appreciated that the benefits also come at a cost. Humans have not behaved responsibly with regard to plastic waste. We have tended to ship our waste off shore, making plastics an ‘out of sight out of mind’ situation. With a life span beyond producer’s and consumer’s needs, plastics have become a serious threat for all life on earth. Beyond obvious impact upon wildlife and environments that have ingested or become suffocated in its mass, plastics break down into almost invisible microplastics that are now ubiquitous and are believed to disrupt the health of all living organism. In order to heighten feelings of empathy I have put myself into the picture, replacing the animal as victim, as unfortunately humans often have a hierarchical view of the world, placing themselves above other lives. This anthropocentric viewpoint is futile as wellbeing is interdependent with a complex and healthy biosphere. As part of the ANAT Synapse residency at the Centre for Marine Bioproduct Development (CMBD) we are working with marine macro algae to produce biodegradable bioplastics to investigate more hopeful narratives and try to do better for humans, animals, plants and the environment.

Background:

BBC Plastics Watch, The Wonder of Plastic, 22 June 2018 https://www.bbc.co.uk/programmes/p06bvjgf

Sea Turtle with Straw up its Nostril: NO TO PLASTIC STRAWS, 10 Aug 2015 https://www.youtube.com/watch?v=4wH878t78bw

Daly N, For Animals, Plastic Is Turning the Ocean Into a Minefield, June 2018 https://www.nationalgeographic.com/magazine/2018/06/plastic-planet-animals-wildlife-impact-waste-pollution/

TATE Art Term – Memento Mori, https://www.tate.org.uk/art/art-terms/m/memento-mori “Memento mori is a Latin phrase meaning ‘remember you must die’…A memento mori is an artwork designed to remind the viewer of their mortality and of the shortness and fragility of human life.…Closely related to the memento mori picture is the vanitas still life. In addition to the symbols of mortality these may include other symbols such as musical instruments, wine and books to remind us explicitly of the vanity (in the sense of worthlessness) of worldly pleasures and goods. The term originally comes from the opening lines of the Book of Ecclesiastes in the Bible: ‘Vanity of vanities, saith the Preacher, vanity of vanities, all is vanity.’ The vanitas and memento mori picture became popular in the seventeenth century, in a religious age when almost everyone believed that life on earth was merely a preparation for an afterlife. However, modern artists have continued to explore this genre.”

Creating Polymer Profiles; biodegradable, strength, printing, dye precipitation, water proofing

We have been manipulating/testing the polymers in order to understand and ‘catalogue’ their properties.

Testing polymers in various water types for biodegradability

Biodegradability: In order to do better, biodegradability is of utmost importance. The polymers I laminated some weeks ago are tested in the various types of waters the CMBD team and I collected during the field trip last week. We see at the 1 hour test (above) that the fresh water sample (FW) collected from Goolwa is the best environment for polymer degradation. This is possibly due to 1) osmosis or 2) more bacteria in the freshwater sample. At this short time frame option 1) is more plausible. Testing for biodegradability will  take place in further temporalities. (Note that the circle craft cutter has come in handy for preparing sample uniformity, thus making changes visible against a standard)

Biofilm Tensile Curves; shows various polymer strength under tensile stress

Tensile strength: Along with biodegradability is the need to serve purpose. Polymers were tested by Flinders University research team for strength under stretch test.

Failed photocopier print on polymer

Copier printing: Polymer was run through the copier. Jet printing inks failed to adhere to the polymer surface resulting in powdery image. I will be doing more work in this area.

Dye (tannin) has precipitated out of the seaweed into the supernatant leaving a bleached biomass residue

Dye: A bleached biomass has separated from the supernatant which has retained dye.

Water proofing: We have been devising different types of experiments to improve water resistance and to reduce polymer leakage. These includes adding waterproofing additives and improving physical properties.

 

 

 

Field Work: collecting water samples to test polymer biodegradability

Feld Work; collecting various water samples from South Australia

10/08/2020

As mentioned in earlier posts, most plastic waste ends up either in landfill or in our waterways. It is important to ‘make visible’ that our marine algal based bioplastics and biopolymers are biodegradable. If they return to the sea, our desire is that they do not add to the plastic waste problem.

Together with CMBD staff member Peng Su and visiting scholar Wanling Cai, I went on a field trip to collect water samples from the South Australian coastline. A variety of locations were selected to include various waters; brackish, mangrove, shallow beach and open sea. We travelled over 400km as all samples were collected on the same day.  The waters will be used to test/prove the biodegradability of seaweed derived plastic polymers.

Collection  point 1: Peng Su collecting brackish water from Goolwa Wharf
Collection point 2: shallow seawater sample from Victor Harbour
Collection point 3: open sea water collection from Cape Jervis
Collection point 4; sandy beach water collected with Wanling Cai, Silver Sands – Aldinga Beach
Collection point 5: mangrove waters collected at Garden Island, Port Adelaide
Collection point 6: Final collection; Niki Sperou collecting Adelaide metropolitan beach water at Glenelg Beach

 

Hacking the polymers; Seaweed tannins for fabric dying

 

 

Fabric dying with Ecklonia Radiata

French literary theorist Roland Barthes explained  in his text “Death of the Author”, that it is not literary convention alone, nor solely the writer that brings meaning to a text but further interpretation comes from those who subsequently read it. From my experience, similar can be said of working with a medium, product or technology. It may be designed for a certain use, however it is the alternative applications that people creatively apply to it that I find fascinating. These uses can be defined as hacking.

There is often a lag between the development of a new product or technology and the understanding of its full potential or risk. These good or bad consequences have been observed since ancient times and explained through such things as Pandora’s Box and Promethean myth. We simply have to look at plastics to observe this in action.

Further, together with CMBD, we have found that certain seaweed polymers can have multiple potentials e.g. from gel, to fibre, to film, to matrix, and can have broad applications.

One of the attributes of seaweeds is that certain varieties contain tannins. CMBD are interested in seaweed tannins for their health benefits. Tannins are bio-molecules that bind to proteins. They are also available in tea and wine. Tannins protect against oxidative stress; an imbalance in the cell’s ability to repair itself. (Free radicals steal electrons from molecules and make them unstable.)Tannins have antioxidant potential, protecting against oxidation as they can donate electrons to free radicals to make them more stable.

After observing the staining capacity of the seaweed tannins when pressing and drying samples between paper, I decided to experiment with the seaweeds we use to make polymers to make fabric dyes. Fabric dying processes were researched and I found that certain chemicals we use to precipitate the bioplastic polymers are also used to create fabric dyes.

Natural fabric dyes are said to be more ecologically friendly than synthetic dyes.

Eklonia Radiata dye

To date I have produced subtle skin toned dyes from the species Ecklonia Radiata and Durvillaea (Bull kelp). These fit within my go to palette of bodily hues; skin, fat, flesh and blood.

Blue Oceans: Blue taxonomy: Watery thinking

Blue Ocean Strategy, Blue Bio-economy and Blue Ocean shift, refer to blue oceans as metaphors for cutting edge strategies and unexplored or uncontested  markets. Working within science and technology frameworks, business idioms are often utilised.

Beyond a purely economic focus, I wish to explore oceanic taxonomies that include broader cultural narratives.

What are the Blue Humanities?

Configurations: A journal of Literature , Science and Technology, Special Issue on Science Studies in the Blue Humanities,                      Vol 27, Number 4 .Fall 2019, John Hopkins University Press.

Configurations dedicated a special issue on Science Studies in the Blue Humanities and identified the Blue Humanities as an emerging field pertaining to cultural meaning of the Ocean through physical, social, ideological, scientific and aesthetic modalities. It was identified that the ocean is storied through a network of knowledge systems; science and technology, fiction, society, economics and politics.

Associated terms for the Blue Humanities;

  • Blue cultural studies
  • terraquious ecocriticism
  • critical ocean studies
  • humanist Oceanic Studies
  • aquatic environmentalism

Authors put forward the idea that it is important to, “think the blue humanities and the discoveries of marine sciences through one another in creative ways.”p443 and that we consider, “The Physical convergences of water, [and] body..,[to] generate an emotional and experiential convergence.p438

The ocean was imagined as;

  • Bodily; salty tears, blood and sweat
  • Immersive
  • Horizontal navigation
  • Fecund; sea milk
  • final frontier
  • global commons
  • extractive zones (colonialism)
  • environmental risk
  • sustainability
  • graveyard; ossification
  • abyss
  • ontology of convergence
  • intertidal zone
  • Escaping anthropocentric existence                                                            and the counterpoint notion of
  • A medium to bring marine domains closer to human reality                and I would add to this the new ecology of
  • Plastisphere

“to glimpse the seas one must…be immersed in highly mediated environments that suggest the entanglements of knowledge, science, economics, and power” Stacy Alaimo