type 1

3 Articles

Implant Fights Diabetes By Making Insulin And Oxygen

October 10, 2023 by 13 Comments

Type 1 diabetes remains a problem despite having an apparently simple solution: since T1D patients have lost the cells that produce insulin, it should be possible to transplant those cells into their bodies and restore normal function. Unfortunately, it’s not actually that simple, and it’s all thanks to the immune system, which would attack and destroy transplanted pancreas cells, whether from a donor or grown from the patient’s own stem cells.

That may be changing, though, at least if this implantable insulin-producing bioreactor proves successful.  The device comes from MIT’s Department of Chemical Engineering, and like earlier implants, it relies on encapsulating islet cells, which are the insulin-producing cells within the pancreas, inside a semipermeable membrane. This allows the insulin they produce to diffuse out into the blood, and for glucose, which controls insulin production in islet cells, to diffuse in. The problem with this arrangement is that the resource-intensive islet cells are starved of oxygen inside their capsule, which is obviously a problem for the viability of the implant.

The solution: electrolysis. The O2-Macrodevice, as the implant is called, uses a tiny power-harvesting circuit to generate oxygen for the islet cells directly from the patient’s own interstitial water. The circuit applies a current across a proton-exchange membrane, which breaks water molecules into molecular oxygen for the islet cells. The hydrogen is said to diffuse harmlessly away; it seems like that might cause an acid-base imbalance locally, but there are plenty of metabolic pathways to take care of that sort of thing.

The implant looks promising; it kept the blood glucose levels of diabetic mice under control, while mice who received an implant with the oxygen-generating cell disabled started getting hyperglycemic after two weeks. What’s really intriguing is that the study authors seem to be thinking ahead to commercial production, since they show various methods for mass production of the cell chamber from standard 150-mm silicon wafers using photolithography.

Type 1 diabetics have been down the “artificial pancreas” road before, so a wait-and-see approach is clearly wise here. But it looks like treating diabetes less like a medical problem and more like an engineering problem might just pay dividends.

EV Charging Connectors Come In Many Shapes And Sizes

April 28, 2022 by 69 Comments

Electric vehicles are now commonplace on our roads, and charging infrastructure is being built out across the world to serve them. It’s the electric equivalent of the gas station, and soon enough, they’re going to be everywhere.

However, it raises an interesting problem. Gas pumps simply pour a liquid into a hole, and have been largely standardized for quite some time. That’s not quite the case in the world of EV chargers, so let’s dive in and check out the current state of play.

AC, DC, Fast, or Slow?

Since becoming more mainstream over the past decade or so, EV technology has undergone rapid development. With most EVs still somewhat limited in range, automakers have developed ever-faster charging vehicles over the years to improve practicality. This has come through improvements to batteries, controller hardware, and software. Charging tech has evolved to the point where the latest EVs can now add hundreds of miles of range in under 20 minutes.

However, charging EVs at this pace requires huge amounts of power. Thus, automakers and industry groups have worked to develop new charging standards that can deliver high current to top vehicle batteries off as quickly as possible.

As a guide, a typical home outlet in the US can deliver 1.8 kW of power. It would take an excruciating 48 hours or more to charge a modern EV from a home socket like this.

In contrast, modern EV charge ports can carry anywhere from 2 kW up to 350 kW in some cases, and require highly specialized connectors to do so. Various standards have come about over the years as automakers look to pump more electricity into a vehicle at greater speed. Let’s take a look at the most common options out in the wild today. Continue reading “EV Charging Connectors Come In Many Shapes And Sizes” →

Eyes On The Prize Of Glucose Monitoring

December 6, 2018 by 18 Comments

People with diabetes have to monitor their blood regularly, and this should not be a shock to anyone, but unless you are in the trenches you may not have an appreciation for exactly what that entails and how awful it can be. To give a quick idea, some diabetics risk entering a coma or shock because drawing blood is painful or impractical at the moment. The holy grail of current research is to create a continuous monitor which doesn’t break the skin and can be used at home. Unaided monitoring is also needed to control automatic insulin pumps.

Alphabet, the parent company of Google, gave up where Noviosense, a Netherlands company owned by [Dr. Christopher Wilson], may gain some footing. Instead of contact lenses which can alter the flow of fluids across the eye, Noviosense places their sensor below the lower eyelid. Fluids here flow regardless of emotion or pain, so the readings correspond to the current glucose level. Traditionally, glucose levels are taken through blood or interstitial fluid, aka tissue fluid. Blood readings are the most accurate but the interstitial fluid is solid enough to gauge the need for insulin injection, and the initial trial under the eyelid showed readings on par with the interstitial measurements.

Hackers are not taking diabetes lying down, some are developing their own insulin and others are building an electronic pancreas.

Via IEEE Spectrum.