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Developing automated platforms for point-of-need testing is a crucial global demand. Digital microfluidics is a promising solution for expanding integrated testing devices featuring ultimate control over the chemical and biological reactions in micro/nanoliter droplets. In this study, robotic digital microfluidics (RDMF) is introduced for the mechanical manipulation of the droplets precisely and inexpensively. A controllable and multifunctional arm equipped with several actuators is responsible for dispensing and manipulating droplets on a disposable superhydrophobic cartridge. The platform has been demonstrated with diverse functions, including droplet dispensing, transport, mixing, aliquoting, and splitting. Moreover, incorporating magnetic and heating modules into the system can realize particle manipulation and droplet heating. The liquid handling operations are investigated from both experimental and modeling perspectives. Handling a wide range of droplet sizes without needing high-voltage electric sources, integrability with different detection techniques, and ease of manufacturing are the main advantages of the RDMF platform compared to conventional digital microfluidic systems. The availability of a complete fluidic toolbox and multiple detection choices make RDMF promising for droplet-based total analysis technology. The system was applied for a urinalysis test to show its versatility in handling complex biochemical assays. The results entirely matched those obtained based on laboratory gold standard techniques. [ABSTRACT FROM AUTHOR]

Alzheimer's disease, a progressive neurological condition, is associated with various internal and external risk factors in the disease's early stages. Early diagnosis of Alzheimer's disease is essential for treatment management. Circulating exosomal microRNAs could be a new class of valuable biomarkers for early Alzheimer's disease diagnosis. Different kinds of biosensors have been introduced in recent years for the detection of these valuable biomarkers. Isolation of the exosomes is a crucial step in the detection process which is traditionally carried out by multi-step ultrafiltration. Microfluidics has improved the efficiency and costs of exosome isolation by implementing various effects and forces on the nano and microparticles in the microchannels. This paper reviews recent advancements in detecting Alzheimer's disease related exosomal microRNAs based on methods such as electrochemical, fluorescent, and SPR. The presented devices' pros and cons and their efficiencies compared with the gold standard methods are reported. Moreover, the application of microfluidic devices to detect Alzheimer's disease related biomarkers is summarized and presented. Finally, some challenges with the performance of novel technologies for isolating and detecting exosomal microRNAs are addressed. [ABSTRACT FROM AUTHOR]