A Widespread Problem

Anemia is easy to diagnose; it just takes a simple blood test. But in rural areas of developing countries, the challenge is reaching the potential patient.

With the help of 3D printing from 3D Systems, Dr. Mei He and graduate student Kimberly Plevniak of Kansas State University are developing a potential solution: A clear plastic chip that can capture a blood sample and be read by a smartphone to diagnose the presence of anemia.

More than two billion people, approximately 30 percent of the world population, are anemic. Most of those affected are pregnant women and preschool children.

In a region such as Indonesia, where there are more than five million pregnant women and 76-million children distributed over 18,307 islands, it is difficult to travel to health centers or clinics for diagnosis. The answer in these remote regions of the world could be a point-of-care (POC) device that doesn’t require specialists for diagnosis.

“Anemia is a very prevalent condition in developing countries, even though it is easily treated with iron supplements or vitamins and can be prevented with a healthy diet,” Plevniak says. “Often in these developing countries, people will have much easier access to smartphones than they will to doctors and trained medical professionals.”

Microfluidics for POC

According to the National Institutes of Health (NIH), point-of-care devices are part of an overall movement that is shifting healthcare toward prevention and early detection of disease. This is especially significant in developing countries with highly isolated populations and lack of modern transportation options.

Microfluidics—the ability to manipulate fluids on a small, typically sub-millimeter, scale—is often critical to POC development. Microfluidic devices enable blood testing on a microchip or small slide, making them less expensive to manufacture and ship, and in the case of smartphone-based devices, easier to use by those without medical training. 

The Kansas State prototype device is a clear plastic chip to which the user adds a blood sample. Test results are produced in less than 60 seconds for subsequent scanning by a smartphone

Faster, Cheaper Prototyping

Prototyping a POC microfluidic device is typically costly and complex. It involves a series of fabrication steps using materials such as polydimethylsiloxane (PDMS) polymer and glass. The process requires a special facility, expensive equipment, and multiple manual interventions. Costs typically run several hundreds of dollars and the process takes a day or two.

“For most POC devices, microfabrication with specialized techniques and infrastructure is needed in a scientific laboratory setting,” says Dr. He.

But 3D printing is changing that scenario. Prototyping a microfluidic device can be done on a lower-end 3D printer with the readily available material in a matter of an hour by an operator with basic training.

“You are looking at about one to two days to produce a PDMS mold and chips versus about an hour to create a prototype with 3D printing,” says Dr. He. “The 3D printer does not require much training to operate. If you look at all the qualities of 3D printing—fast, one-step process, easy to use—it is perfect for this type of prototyping.”

Selecting the Right Printer

Plevniak and Dr. He worked with D3 Technologies, a design and engineering systems integrator and 3D Systems partner based in Springfield, Missouri, to select the best 3D printer, material and print set-up for their needs.

« Nous avons reçu beaucoup d'aide de la part de D3 avant de prendre de décision d'acheter l'imprimante ProJet® 1200 de 3D Systems déclare Plevniak. « Nous avons pu poser beaucoup de questions avant de passer la commande et D3 nous a apporté un échantillon de matériau transparent afin que nous puissions le voir le tester. D3 a également organisé une visite sur le site d'un client afin que nous puissions voir l'imprimante ProJet 1200 en action. »

L'imprimante ProJet 1200 de 3D Systems convient parfaitement pour le prototypage d'appareils microfluidiques. Elle est conçue pour les pièces de petite taille, précises, comportant beaucoup de détails et les modèles de moulage. La machine présente un faible encombrement, elle est très abordable, peut fonctionner n'importe où en toute sécurité et son utilisation est extrêmement simple.

With a 43 x 27 x 150 mm (1.69 x 1.06 x 5.9 inches) print volume, the ProJet 1200 micro stereolithography (SLA) system prints 30-micron layers at a 585-dpi resolution, resulting in fine feature details that are true to the CAD model.

Prototyping Without Worry

« Nous avons sélectionné l'imprimante ProJet 1200 pour ce projet en raison de sa résolution de haute qualité, du choix des matériaux et d'un prix raisonnable », indique Plevniak. « Le fait d'avoir des détails fins est important pour l'impression de très petits canaux microfluidiques. Le modèle ProJet 1200 peut imprimer du matériau VisiJet® FTX Clear, un plastique durcissable aux UV qui offre la transparence optique dont nous avons besoin pour les canaux microfluidiques de notre appareil. »

Convenience, cleanliness, and reliability are also important 3D printer attributes for Plevniak.

« J'apprécie la façon dont les cartouches de matériau sont chargées dans l'imprimante » déclare-t-elle. « Cela facilite beaucoup la production et entraîne moins de désordre. Les autres imprimantes 3D utilisent des pompes au lieu de cartouches ; celles-ci rendent la zone plus sale et tombent en panne facilement. L'imprimante ProJet 1200 nous permet de nous concentrer sur la fabrication de nos puces, sans avoir à nous soucier d'une panne de l'imprimante ou du nettoyage après chaque impression. »

Broad Implications Worldwid

The POC prototype is currently being tested using blood samples from the University of Kansas Medical Center Biospecimen Repository. Test results will be used to further optimize the device for diagnosing different levels of anemia in the blood. An invention disclosure has been filed with the Kansas State University Research Foundation, a non-profit corporation responsible for managing technology transfer activities.

Dr. He and Plevniak are working with a colleague at Kansas State to develop a companion app for the anemia POC chip that could manage data from the blood sample and send results to medical professionals.

Dr. He thinks that the Kansas State anemia-detection approach could have broad implications throughout the world. 

“This device offers an adaptive diagnostic strategy that is truly transferable to low-income countries to improve healthcare quality.”