Introduction

Tmek was designed to have a diagnostic test for malaria to answer the need of a rapid and effective screening of the population where the socio-economic conditions make the solutions currently available on the market inappropriate or ineffective. Almost 450,000 people die every year in Africa from this disease, which would be easily treated if early diagnosed. TMek is a lab-on-chip diagnostic test, suitable for early detection of malaria.

Technical features

TMek is a compact system, according to the “lab-on-chip” approach, consisting of a low-cost “disposable” microchip connected to an electronic reading module. It is based on the magnetic properties of infected red blood cells (RBCs) and emozoin crystals (HC) produced by plasmodium, the malaria pathogen. A drop of blood is collected on a slide then placed in contact with the silicon chip. Infected RBCs and HCs are attracted to magnetic concentrators, while healthy RBCs sediment. The detection takes place by measuring the variation in electrical impedance at each concentrator. The Gold Standard for these analyses is the observation of the blood drop under a microscope made manually and with long times by an experienced operator, not always available in African dispensaries; alternatively, either PCR, a precise but slow and expensive technique not available in developing countries, or Rapid Diagnostic Tests (RDT) are used, characterized by analysis times of around 25 min and low sensitivity (false positives > 30%, due to the latent presence of antigen in the patient’s body). The market for TMek is that of the RDT, with more than 312 million devices sold, despite the known limits of this technology.

Possible Applications

• Early malaria diagnosis;
• monitoring of the intensity and stage of the disease by quantifying the number of infected red blood cells in the sample;
• Monitoring of the effectiveness of the therapy until healing has taken place;
• diagnosis of other parasites with magnetic properties: e.g. schistosoma mansoni eggs.

Advantages

• Sensitivity level comparable with the Gold Standard;
• absence of false positives;
• pan-plasmodic test: identifies all types of malaria parasites;
• compatibility with use in tropical areas without specialized personnel;
• speed of execution <5 min (RDT 25 min, Gold Standard and PCR 40 min);
• cost <10 €, comparable with RTD.