FAST: Size-Selective, Clog-Free Isolation of Rare Cancer Cells from Whole Blood at a Liquid–Liquid Interface

Abstract

Circulating tumor cells (CTCs) have great potential to provide minimally invasive ways for the early detection of cancer metastasis and for the response monitoring of various cancer treatments. Despite the clinical importance and progress of CTC-based cancer diagnostics, most of the current methods of enriching CTCs are difficult to implement in general hospital settings due to complex and time-consuming protocols. Among existing technologies, size-based isolation methods provide antibody-independent, relatively simple, and high throughput protocols. However, the clogging issues and lower than desired recovery rates and purity are the key challenges. In this work, inspired by antifouling membranes with liquid-filled pores in nature, clog-free, highly sensitive (95.9 ± 3.1% recovery rate), selective (>2.5 log depletion of white blood cells), rapid (>3 mL/min), and label-free isolation of viable CTCs from whole blood without prior sample treatment is achieved using a stand-alone lab-on-a-disc system equipped with fluid-assisted separation technology (FAST). Numerical simulation and experiments show that this method provides uniform, clog-free, ultrafast cell enrichment with pressure drops much less than in conventional size-based filtration, at 1 kPa. We demonstrate the clinical utility of the point-of-care detection of CTCs with samples taken from 142 patients suffering from breast, stomach, or lung cancer.

Circulating tumor cells detected by lab-on-a-disc: Role in early diagnosis of gastric cancer

“…However, the non-uniform and randomly distributed pores and low porosity of these membranes can cause inconsistent and lower-than-desired recoveries and purity [28, 29]. Here, we used a centrifugal microfluidic device operated in FAST mode to overcome the limitations of track-etched based filtration using a hydrodynamic approach [10]. FAST provides uniform, clog-free, and efficient filtration under a lower pressure drop when compared to conventional separation, leading to highly sensitive (>95.9% recovery), selective (~2.5 log depletion of white blood cells), rapid (>3 mL/min), and label-free isolation of CTCs from whole blood without prior sample treatment [10, 11].…”

“…The “FAST disc” centrifugal microfluidic system, which conducts size-selective CTC isolation through membrane pores filled with a stably held liquid throughout the filtration process, was used to detect CTCs [10, 11]. FAST disc isolation of CTCs allows the use of whole blood without any sample treatment steps (e.g., dilution and red blood cell lysis).…”

“…To identify CTCs directly in blood, we recently developed a centrifugal microfluidic system based on a new fluid-assisted separation technique (FAST), in which size-based separation occurs within a centrifugal microfluidic device at a liquid-liquid interface, instead of the conventional liquid-gas interface [10, 11]. In a previous study, we showed that FAST enabled the highly sensitive, selective, rapid, and label-free isolation of CTCs from whole blood without prior sample treatment [10].…”

“…In a previous study, we showed that FAST enabled the highly sensitive, selective, rapid, and label-free isolation of CTCs from whole blood without prior sample treatment [10]. …”

Circulating tumor cells detected using fluid‐assisted separation technique in esophageal squamous cell carcinoma

“…Although immunohistochemistry, reverse transcriptase polymerase chain reaction (PCR), flow cytometry, and the CellSearch system are currently used in clinical research, each technology has its own methodological limitations and uncertainty and may lead to different results. To directly identify CTCs in the blood, we recently developed a centrifugal microfluidic system based on a new fluid‐assisted separation technique (FAST), in which size‐based separation occurs within a centrifugal microfluidic device at a liquid–liquid interface, instead of the conventional liquid–gas interface . In a previous study, we showed that FAST enabled a highly sensitive, selective, rapid, and label‐free isolation of CTCs from whole blood directly without prior sample manipulation .…”