A new low-cost technology that transforms a cell phone into a powerful, mobile microscope could significantly improve malaria diagnoses and treatment in developing countries, scientists say.
The technology includes an add-on device, which is similar in look and feel to a protective cell phone case.
It makes use of a smartphone’s camera to produce high-resolution images of objects 10 times smaller than the thickness of a human hair, said Gerard Cote, professor of biomedical engineering and director of the Texas A&M Engineering Experiment Station’s Center for Remote Health Technologies and Systems.
Cote developed the instrument, known as a mobile-optical-polarisation imaging device (MOPID), which is capable of accepting a small cartridge containing a patient’s blood-smear sample.
The sample is then imaged using polarised light in order to detect the presence of hemozoin crystals. Hemozoin crystals are the byproduct of the malaria parasite, and they occur in the blood of an infected host.
As polarised light bounces off of these crystals, they appear as tiny bright dots when observed through the phone’s camera lens – enabling an instant, accurate diagnosis.
While polarised light has been the preferred option for malaria detection due to its increased sensitivity, its implementation into mainstream microscopy has been hindered by its complex configurations, maintenance, size and cost.
“What we’ve achieved with MOPID is the design of a polarised microscope platform using a cellphone, which can detect birefringence in histological specimens infected with the malaria parasite,” Cote said.
“It’s a simple, low-cost, portable device that we believe is more sensitive than the standard microscope that uses white light and just as accurate as the more costly and complex benchtop version of a polarised microscope,” he said.
MOPID could represent a significant advancement in the detection methods for malaria, a disease that the World Health Organisation estimates was responsible for 584,000 deaths in 2013.
The MOPID system has demonstrated both the resolution and specificity to detect malaria with both iOS- and Android-based devices and requires less user expertise than traditional microscopy, Cote said.
That user-friendly aspect, coupled with the system’s portability and expected low cost of about USD 10 per unit, makes it an easily adoptable technology in low-resource areas ravaged by malaria, he added.
Analysis of a blood sample can be instantaneously made with the patient in the field without the need for a mobile network.
Cote and graduate student Casey Pirnstill are continuing to refine the design of the system by making it more compact as well as improving its durability. Plans for in vivo field-testing are scheduled to take place in Rwanda, Africa in the near future, Cote said.
The research is published in the journal Scientific Reports.