Jell-O device detects organ failure

U. TEXAS-AUSTIN (US) — Using only aluminum foil, gelatin, a 12-cent LED light, and a few other inexpensive materials, researchers have developed a sensor that can detect pancreatitis quickly and easily.

About the size of a matchbox, the sensor relies on a two-step process to diagnose the disease, a sudden inflammation of the pancreas that can lead to severe stomach pain, nausea, fever, shock, and, in some cases, death.

“We’ve turned Reynold’s Wrap, Jell-O, and milk into a way to look for organ failure,” says Brian Zaccheo, graduate student in the lab of Richard Crooks, professor of chemistry and biochemistry at University of Texas at Austin.

In step one, a bit of blood extract is dropped onto a layer of gelatin and milk protein. If there are high levels of trypsin, an enzyme that is overabundant in the blood of patients with acute pancreatitis, the trypsin will break down the gelatin in much the same way it breaks down proteins in the stomach.

In step two, a drop of sodium hydroxide (lye) is added. If the trypsin levels were high enough to break down that first barrier, the sodium hydroxide can trickle down to the second barrier, a strip of Reynold’s wrap, and go to work dissolving it.

The foil corrodes, and with both barriers now permeable, a circuit is able to form between a magnesium anode and an iron salt at the cathode. Enough current is generated to light up a red LED. If the LED lights up within an hour, acute pancreatitis is diagnosed.

“In essence, the device is a battery having a trypsin-selective switch that closes the circuit between the anode and cathode,” the authors write in their study, published in the journal Analytical Chemistry.

The sensor has a number of potential uses, most notably in developing countries or after a natural disaster where more complex testing is difficult. Also the device’s speed could make it worthwhile as a first-line measure, even in well-stocked hospitals.

“I want to develop biosensors that are easy to use but give a high level of sensitivity,” Zaccheo says. “All you need for this, for instance, is to know how to use a dropper and a timer.”

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