A Non-Invasive Method for Detecting a Deadly Form of Malaria: Plasmodium Falciparum

Undergraduate Research Scholarship - College of EngineeringDenman Research Forum (2014) - 1st place in EngineeringMalaria is an infectious disease transmitted by mosquitoes that affects 40% of the world’s population, resulting in 300 to 500 million new infections yearly. Of the different types of malaria, Plasmodium falciparum (PF) is the most prevalent and deadly parasite in humans. While treatment is available, PF is often difficult to detect with a blood draw because the parasite sequesters in internal organs during various phases of its reproductive cycle. PF infects red blood cells, converting the hemoglobin in the red blood cells into iron rich particles called hemozoin. The hemozoin crystals can be as large as 1 micron in size and several clusters are stored in the food vacuoles of the parasite since they are toxic to the host and PF alike. PF is predominant in low and middle-income countries where pathologists and microscopes are not widely available to confirm the presence of this species of malaria. Consequently, an inexpensive, non-invasive, continuous, and direct indicator of PF is needed. The goal of this research is to exploit the paramagnetic properties of hemozoin and to develop a non-invasive, electromagnetic method of detecting infected red blood cells. An electromagnetic probe (EM probe) comprising of a dual coaxial coil is used to detect iron oxide particles by using sensitive lock-in amplification of detector voltage. Measurements with this probe are performed on iron oxide particles (less than 44 microns – 720 microns) before conducting measurements on PF food vacuoles. Results show that measurements of micron sized iron particles on the scale of less than 44 microns are repeatable. Preliminary measurements with food vacuoles trapped in small capillary tubes confirm feasibility of the method with indicated voltage differences of 44.7 ± 25.7 mV versus voltage readings for a control (capillary tube without trapped food vacuoles) of 16.2 ± 4.3 mV with great potential for increased sensitivity. Preliminary optimization of the EM probe has resulted in greater sensitivity but considerable room for improvement still exists. This research demonstrates great promise for finding an alternative to existing methods (mainly peripheral blood draws) for the detection of PF. In addition to being non-invasive, the method described herein can provide detection results that can be interpreted in simple binary fashion (e.g. a readout red LED lighting up indicating the presence of infected cells and a green LED lighting up indicating no infection). This method therefore potentially lends itself to infected individuals being able to monitor themselves continuously throughout the day and getting timely treatment after confirmation, without the need for a peripheral blood draw, or the presence of a trained pathologist to interpret the microscopic examination of the drawn blood.A five-year embargo was granted for this item.Academic Major: Mechanical Engineerin