Hacked Heating Instruments For The DIY Biology Lab

November 12, 2018 by Dan Maloney 4 Comments

[Justin] from The Thought Emporium takes on a common molecular biology problem with these homebrew heating instruments for the DIY biology lab.

The action at the molecular biology bench boils down to a few simple tasks: suck stuff, spit stuff, cool stuff, and heat stuff. Pipettes take care of the sucking and spitting, while ice buckets and refrigerators do the cooling. The heating, however, can be problematic; vessels of various sizes need to be accommodated at different, carefully controlled temperatures. It’s not uncommon to see dozens of different incubators, heat blocks, heat plates, and even walk-in environmental chambers in the typical lab, all acquired and maintained at great cost. It’s enough to discourage any would-be biohacker from starting a lab.

[Justin] knew It doesn’t need to be that way, though. So he tackled two common devices: the incubator and the heating block. The build used as many off-the-shelf components as possible, keeping costs down. The incubator is dead simple: an insulated plastic picnic cooler with a thermostatically controlled reptile heating pad. That proves to be more than serviceable up to 40°, at the high end of what most yeast and bacterial cultures require.

The heat block, used to heat small plastic reaction vessels called Eppendorf tubes, was a little more complicated to construct. Scrap heat sinks yielded aluminum stock, which despite going through a bit of a machinist’s nightmare on the drill press came out surprisingly nice. Heat for the block is provided by a commercial Peltier module and controller; it looks good up to 42°, a common temperature for heat-shocking yeast and tricking them into taking up foreign DNA.

We’re impressed with how cheaply [Justin] was able to throw together these instruments, and we’re looking forward to seeing how he utilizes them. He’s already biohacked himself, so seeing what happens to yeast and bacteria in his DIY lab should be interesting.

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History Of White LEDs

October 29, 2018 by Brian Benchoff 122 Comments

Compared to incandescent lightbulbs, LEDs produce a lot more lumens per watt of input power — they’re more efficient at producing light. Of course, that means that incandescent light bulbs are more efficient at producing heat, and as the days get shorter, and the nights get colder, somewhere, someone who took the leap to LED lighting has a furnace that’s working overtime. And that someone might also wonder how we got here: a world lit by esoteric inorganic semiconductors illuminating phosphors.

The fact that diodes emit light under certain conditions has been known for over 100 years; the first light-emitting diode was discovered at Marconi Labs in 1907 in a cat’s whisker detector, the first kind of diode. This discovery was simply a scientific curiosity until another discovery at Texas Instruments revealed infrared light emissions from a tunnel diode constructed from a gallium arsenide substrate. This infrared LED was then patented by TI, and a project began to manufacture these infrared light emitting diodes.

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Micro-Organisms Give Up The Volts In This Biological Battery

July 27, 2018 by Donald Papp 18 Comments

Battery cells work by chemical reactions, and the fascinating Hybrid Microbial Fuel Cell design by [Josh Starnes] is no different. True, batteries don’t normally contain life, but the process coughs up useful electrons all the same; 1.7 V per cell in [Josh]’s design, to be precise. His proof of concept consists of eight cells in parallel, enough to give his cell phone a charge via a DC-DC boost converter. He says it’s not known how long this can be expected to last before the voltage drops to an unusable level, but it works!

Eight-cell, 3D printed proof of concept.

There are two complementary sides to each cell in [Josh]’s design. On the cathode side are phytoplankton; green micro algae that absorb carbon dioxide and sunlight. On the anode side are bacteria that break organic material (like food waste) into nitrates, and expel carbon dioxide. Version 2 of the design will incorporate a semi-permeable membrane between the cells that would allow oxygen and carbon dioxide to be exchanged while keeping the populations of micro-organisms separate; this would make the biological processes more complementary.

A battery consisting of 24 cells and a plumbing system to cycle and care for the algae and bacteria is the ultimate goal, and we hope [Josh] can get closer to that now that his project won a $1000 cash prize as one of the twenty finalists in the Power Harvesting Challenge portion of the Hackaday Prize. (Next up is the Human Computer Interface Challenge, just so you know.)

Modular Blocks Help Fight Disease

May 18, 2018 by Bryan Cockfield 3 Comments

When engineering a solution to a problem, an often-successful approach is to keep the design as simple as possible. Simple things are easier to produce, maintain, and use. Whether you’re building a robot, operating system, or automobile, this type of design can help in many different ways. Now, researchers at MIT’s Little Devices Lab have taken this philosophy to testing for various medical conditions, using a set of modular blocks.

Each block is designed for a specific purpose, and can be linked together with other blocks. For example, one block may be able to identify Zika virus, and another block could help determine blood sugar levels. By linking the blocks together, a healthcare worker can build a diagnosis system catered specifically for their needs. The price tag for these small, simple blocks is modest as well: about $0.015, or one and a half cents per block. They also don’t need to be refrigerated or handled specially, and some can be reused.

This is an impressive breakthrough that is poised to help not only low-income people around the world, but anyone with a need for quick, accurate medical diagnoses at a marginal cost. Keeping things simple and modular allows for all kinds of possibilities, as we recently covered in the world of robotics.

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Computers May Someday Need A Drink

April 21, 2018 by Brian McEvoy 16 Comments

“We want to put water right into your processor.” If that statement makes you sweat, that is good. Sweating is what we’re talking about, but it’s more involved than adding some water like a potted plant. Sweating works naturally by allowing liquid to evaporate, and that phase change is endothermic which is why it feels cool. Evaporative coolers that work in this way, also known as swamp coolers, haven’t been put into computers before because they are full of sloshy water. Researchers in South Korea and the United States of America have been working on an evaporative cooling system mimicking the way some insects keep themselves cool by breathing through their exoskeletons while living in damp soil.

Springtails are little bugs that have to keep the water and air separate, so they don’t drown in the wet dirt where they live. Mother Nature’s solution was for them to evolve to do this with columns that have sharp edges at the exit. Imagine you slowly add water to a test tube, it won’t spill as soon as you reach the top, it will form a dome. This is the meniscus. At a large scale, say a river dam, as soon as you get over the dam you would expect spillage, but at the test tube level you can see a curve. At the scale of the springtail, exuded water will form a globe and resist water pressure. That resistance to water pressure allows this type of water cooling to self-regulate. Those globes provide a lot of surface area, and as they evaporate, they allow more water to replenish the globe. Of course, excessive pressure will turn them into the smallest squirt guns.

We have invented a lot by copying Mother Nature. Velcro was inspired by burrs, and some of our most clever robots copy insects. We can also be jerks about it.

Carbon Augmented Spider Silk

March 15, 2018 by Brian McEvoy 22 Comments

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].

A Salty Solution For A Dead Nexus 5X

January 16, 2018 by Tom Nardi 100 Comments

If you’re an Android fan, there’s a good chance you’ve heard of the Nexus 5X. The last entry in Google’s line of low-cost Nexus development phones should have closed the program on a high note, or at the very least maintained the same standards of quality and reliability as its predecessor. But unfortunately, a well known design flaw in the Nexus 5X means that the hardware is essentially a time-bomb. There are far too many reports of these phones entering into an endless bootloop right around the one year mark to say it’s just a coincidence.

The general consensus seems to be that faulty BGA chip soldering on the CPU works lose after about a year or so of thermal stress. Whatever the reason, [hillbillysam] recently found himself the proud owner of a dead Nexus 5X. Resigned to the fact that he would need to get a new phone, he at least wanted to get some of his data off the device before it went to that big landfill in the sky.

As it turns out these bootlooped phones can temporarily be revived by cooling them down, say by putting them in the freezer for a few hours. There’s plenty of debate as to why this works, but even our own [Lewin Day] can testify that it does seem to get the phone booting again; though only until it comes back up to operating temperature. With this in mind, [hillbillysam] reasoned that if he kept the phone as cold as possible while it was running, it may stay operational long enough for him to pull his files off of it over USB.

He couldn’t exactly freeze the phone in a block of ice, but remembering his high school chemistry, he came up with something pretty close. By adding salt to water, you can significantly lower temperature at which it freezes. Putting the phone into a watertight bag and submerging it in this supercooled solution is an easy and non-destructive way of keeping it very cold while still being accessible over USB.

His Nexus 5X was able to keep kicking the whole time it was luxuriating in its below-freezing saltwater bath, giving him plenty of time to copy everything he needed. It doesn’t sound like the kind of spa day we’d like to have personally, but to each their own.

If your Nexus 5X has met a similar fate, you may want to take a look at our previous coverage about the issue. While your mileage may vary, we’ve reported on a couple of success stories so it’s worth a shot.

[via /r/nexus5x]