Introduction to In Vitro Diagnostic Devices

Healthcare investment keeps on increasing substantially in recent years. Such investment has also focused on fighting major diseases, enabled by the novel invention of cost-effective and valid drug development for treatment and side effect reduction, along with improved vector control. In addition, the demand for diagnostics that is essential in determining prognosis, identifying disease stages, monitoring treatment, and assessing the spreading as health services has expanded. Molecular-based diagnostics is critical for prevention, identification, and treatment of disease. Current laboratory analyses support correct diagnosis in over 70 % of all diseases and can be used to aid the continuous monitoring of drug therapy. However, classic diagnostic technologies are not completely well suited to meeting the expanded testing requirement because they rely on complicated sample purification and sophisticated instruments which are labor-intensive, timely, and expensive and require well-trained operators. One of the main challenges for industry is to develop fast, relatively accurate, easy-to-use, and inexpensive devices. In addition to the improved efficiency in laboratory diagnostics, there has been a trend toward a more decentralized diagnostics which occurs directly at patients’ bedside, in outpatient clinics, or at the sites of accidents, so-called point-of-care (POC) systems. The concept of POC testing is mainly for the patient, so short turnaround time, minimum sample preparation, reagent storage and transferring, user-friendly analytical instruments, and digital or visible quantitative or semiquantitative single readout are required. POC test is a great option of potential in vitro diagnostics (IVD) for resource-limited settings. It is clear that on-site or minimum sample preparation and on-chip storage limit the delays that caused by transport and preparation of clinical samples. Shorter turnaround time leads to rapid clinical decision-making and may save fatal consequences. No previous knowledge in sample analysis should be required, so elders can perform the tests at home with minimum training to improve health outcome. Lateral-flow immunoassay (LFIA) devices, for example, which were originally proposed in the 1980s, remain popular largely because of their design simplicity. The purpose of this article is to introduce readers with basic information regarding the LFIA approach that we think the most representative product of IVD test for solving global health issues.