Researchers from Johns Hopkins University School of Medicine recently transported human blood samples across 161 miles of Arizona desert using a Latitude Engineering HQ-40 UAS, and in the process, set a new delivery distance record for medical UAS.

During the three-hour flight, which took off and landed at the same airfield on a UAS test range, the UAS’ on-board payload system maintained temperature control, which helped make sure that the samples were usable for laboratory analysis after landing.

“We expect that in many cases, drone transport will be the quickest, safest and most efficient option to deliver some biological samples to a laboratory from rural or urban settings,” says Timothy Amukele, M.D., Ph.D., assistant professor of pathology at the Johns Hopkins University School of Medicine.

Amukele is also the senior author of a report on the findings that was published in the American Journal of Clinical Pathology on September 6, which can be found here.

“Drones are likely to be the 21st century’s best medical sample delivery system,” Amukele adds.

The investigators for this project built off of the previous work conducted by Amukele’s team, and collected pairs of 84 blood samples at the University of Arizona in Tucson. The samples were then driven 76 miles to an airfield.

After one sample from each pair was loaded onto the UAS, the UAS flew the samples 161 miles. The Johns Hopkins team designed a temperature-controlled chamber that contained the samples during their flight.

While those samples were being flown via UAS to their destination, the other sample of each pair was held in a car at the airfield, and active cooling was used to maintain target temperature.

The average temperature of the samples flown by UAS was 76.6°F, while the temperature for the samples that were not flown was 81.1°F.

There were a number of additional precautions that went into conducting this test, starting with it being conducted in restricted airspace at an unpopulated military test range. All other air traffic at the test range was cleared. A certified remote pilot controlled the UAS, and used a radio link between the UAS’ onboard flight computer and the ground control station.

Also, samples were packed and transported according to the guidelines of the International Air Transport Association.

After the flight, every sample was transported 62 miles by car to the Mayo Clinic in Scottsdale, Arizona. Every sample was tested for 17 of the 19 most common chemistry and hematology tests, and results showed that “flown and not-flown paired samples showed similar results for red blood cell, white blood cell and platelet counts and sodium levels, among other results.”

Small differences that are still statistically significant “were seen in glucose and potassium levels, which also show variation in standard transport methods,” like automobile transport.

These differences were a result of “chemical degradation from slightly warmer temperature in the not-flown samples.”

Previously, the Johns Hopkins team studied the impact of UAS transportation on the “chemical, hematological and microbial makeup of drone-flown blood samples over distances up to 20 miles.” The team says that none of the samples were negatively affected.