A line-art diagram of the microfluidic device. On the left, in red text, it says "Fibrillization trigger (CPB pH 5.0). There is a rectangular outline of the chip in grey, with a sideways trapezoid on the left side narrowing until it becomes an arrow on the right. At the right is an inset picture of the semi-transparent microfluidic chip and the text "Negative Pressure (Pultrusion)." Above the trapezoid is the green text "MaSp2 solution" and below is "LLPS trigger (CPB pH 7.0)" in purple. The green, purple, and red text correspond with inlets labeld 1, 2, and 3, respectively. Three regions along the arrow-like channel from left to right are labeled "LLPS region," "pH drop," and in a much longer final section "Fiber assembly region."

Synthetic Spider Silk

While spider silk proteins are something you can make in your garage, making useful drag line fibers has proved a daunting challenge. Now, a team of scientists from Japan and Hong Kong are closer to replicating artificial spider silk using microfluidics.

Based on how spiders spin their silk, the researchers designed a microfluidic device to replicate the chemical and physical gradients present in the spider. By varying the amount of shear and chemical triggers, they tuned the nanostructure of the fiber to recreate the “hierarchical nanoscale substructure, which is the hallmark of native silk self-assembly.”

We have to admit, keeping a small bank of these clear, rectangular devices on our desk seems like a lot less work than keeping an army of spiders fed and entertained to produce spider silk Hackaday swag. We shouldn’t expect to see a desktop microfluidic spider silk machine this year, but we’re getting closer and closer. While you wait, why not learn from spiders how to make better 3D prints?

If you’re interesting in making your own spider silk proteins, checkout how [Justin Atkin] and [The Thought Emporium] have done it with yeast. Want to make your spider farm spiders have stronger silk? Try augmenting it with carbon.

Spider Silk, Spider Silk, Made Using A Strain Of Yeast

Companies spend thousands developing a project for the market, hoping their investment will return big. Investing like this happens every day and won’t shock anyone. What may surprise you is someone who spends more than a decade and thousands of their own dollars to make an open-source version of a highly-marketable product. In this case, we’re talking about genetically modified yeast that produces spider silk. If that sounds like a lead-in to some Spiderman jokes and sci-fi references, you are correct on both accounts. [Justin Atkin] had some geneticist work under his belt when he started, so he planned to follow familiar procedures like extracting black widow DNA, isolating and copying the silk genes, and pasting them into a yeast strain. Easy peasy, right? Naturally, good science doesn’t happen overnight.

There are a few contenders for the strongest spider silk among which the golden silk orb-weaver gets the most attention, but the black widow’s webbing is nearly as strong, and [Justin] is happy to wear black widow inspired bling, whereas the golden orb-weaver looks like it crawled out of Starship Troopers. His first attempt to extract DNA starts with a vial of preserved nightmare fuel spider specimens because that is a thing you can just go online and buy. Sadly, they were candied in alcohol, and that obliterates DNA, so he moved to dried specimens from breeders, which also failed to produce results, and those were just the landmark hangups.

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Carbon Augmented Spider Silk

Some of the creepy-crawlers under our feet, flitting through the air, and waiting on silk webs, incorporate metals into their rigid body parts and make themselves harder. Like Mega Man, they absorb the metals to improve themselves. In addition to making their bodies harder, silk-producing creatures like worms and spiders can spin webs with augmented properties. These silks can be conductive, insulating, or stronger depending on the doping elements.

At Italy’s University of Trento, they are pushing the limits and dosing spiders with single-wall carbon nanotubes and graphene. The carbon is suspended in water and sprayed into the spider’s habitat. After the treatment, the silk is measured, and in some cases, the silk is significantly tougher and surpasses all the naturally occurring fibers.

Commercial spider silk harvesting hasn’t been successful, so maybe the next billionaire is reading this right now. Let’s not make aircraft-grade aluminum mosquitoes though. In fact, here’s a simple hack to ground mosquitoes permanently. If you prefer your insects alive, maybe you also like their sound.

Thank you for the tip, [gippgig].

Unlocking Silk For Uses As An Optical, Digital, Biological, Or Food Storage Device

[Fiorenzo Omenetto] gave a TED talk early last year to illustrates a lot of intriguing uses for silk. Before watching his presentation we would have been hard pressed to come up with a use for silk other than in clothing. But it turns out that investigating how silk worms create the material has led to a range of other applications. You can see the full talk embedded after the break.

One of the first things he shows off is a transparent film made of silk. The material looks almost like cellulose film, and can function in a similar way. [Fiorenzo] shines a laser through a silk slide that has a micro-dot of words embedded in it. the result is a clearly readable message projected on the wall. The film can also be used for holographic images.

But it’s the biodegradable aspects that are clearly the breakthrough here. A slide of silk can be doped with pharmaceuticals and programmed for a very specific time release. This way the drugs no longer need to be stored under refrigeration, and can be reclaimed using only water. The same properties allow one to manufacture disposable objects that will quickly and completely degrade. But there’s even more, if you dope the material with a conductor like gold it becomes a disposable circuit.

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