Preconcentration-enhanced immunosensing for whole human cancer cell lysate based on a nanofluidic preconcentrator

Microspectrometer-Enabled Real-Time Concentration Monitoring in the Microfluidic Protein Enrichment Chip

This study presents a novel microspectrometer-integrated microfluidic system for real-time protein concentration monitoring. The device employs electrokinetic principles for efficient protein preconcentration in a PDMS and Nafion film channel. Using FITC-labeled BSA as a model protein, the system demonstrated a linear correlation between protein concentration and absorbance at 491 nm. Notably, it achieved a 833-fold concentration increase from an initial 10 nM within 20 min. The compact microspectrometer system offers enhanced accuracy and sensitivity compared to traditional fluorescence microscopy methods. This innovation presents a promising solution for portable and point-of-care diagnostic applications, facilitating timely disease detection and monitoring. The findings highlight the potential for this technology to advance protein analysis and biomarker discovery in clinical settings, potentially improving patient outcomes through enhanced diagnostic capabilities.

A survey of electrokinetically-driven microfluidics for cancer cells manipulation

Cancer is one of the leading causes of annual deaths worldwide, accounting for nearly 10 million deaths each year. Metastasis, the process by which cancer spreads across the patient's body, is the main cause of death in cancer patients. Because the rising trend observed in statistics of new cancer cases and cancer-related deaths does not allow for an optimistic viewpoint on the future-in relation to this terrible disease-the scientific community has sought methods to enable early detection of cancer and prevent the apparition of metastatic tumors. One such method is known as liquid biopsy, wherein a sample is taken from a bodily fluid and analyzed for the presence of CTCs or other cancer biomarkers (e.g., growth factors). With this objective, interest is growing by year in electrokinetically-driven microfluidics applied for the concentration, capture, filtration, transportation, and characterization of CTCs. Electrokinetic techniques-electrophoresis, dielectrophoresis, electrorotation, and electrothermal and EOF-have great potential for miniaturization and integration with electronic instrumentation for the development of point-of-care devices, which can become a tool for early cancer diagnostics and for the design of personalized therapeutics. In this contribution, we review the state of the art of electrokinetically-driven microfluidics for cancer cells manipulation.

A compact microfluidic chip with integrated impedance biosensor for protein preconcentration and detection

In this study, a low-cost, compact biochip is designed and fabricated for protein detection. Nanofractures formed by self-assembled gold nanoparticles at junction gaps are applied for ion enrichment and depletion to create a trapping zone when electroosmotic flow occurs in microchannels. An impedance measurement module is implemented based on the lock-in amplifier technique to measure the impedance change during antibody growth on the gold electrodes which is caused by trapped proteins in the detection region. The impedance measurement results confirm the presence of trapped proteins. Distinguishable impedance profiles, measured at frequencies in the range of 10-100 kHz, for the detection area taken before and after the presence of proteins validate the performance of the proposed system.