微流控芯片上样品连续介电过滤及微藻检测

Sequential dielectrophoresis particle separation and resistive pulse detection in an electrokinetic microfluidic chip

报道一种可全自动、顺序实现样品中杂质颗粒介电过滤和目标颗粒电阻脉冲检测、计数和尺寸判定的微流控芯片装置.根据杂质颗粒与目标颗粒尺寸和介电特性的不同,在芯片通道上顺序设计了介电泳(DEP)分离区和电阻脉冲(RPS)检测区,通过理论模拟,优化并确定芯片结构和尺寸,并进行实验验证,实现了3μm聚苯乙烯杂质颗粒的介电过滤以及近头状伪蹄形藻的检测和计数.研究表明:颗粒收集通道的位置布置对于颗粒的收集效果有重要影响;检测到的近头状伪蹄形藻的RPS信号信噪比(>20)较高,即DEP分离用的高压电源并没有明显影响RPS信号的信噪比.本研究对于发展成分复杂的单细胞生物样品快速检测和分析的微流控芯片便携式设备具有一定的借鉴价值.

This paper reports a microfluidic lab-on-chip device which can automatically and sequentially realize the impurity di- electrophoresis separation and resistance pulse detection, count- ing, and sizing of the target particles. According to the differ- ences of the size and dielectric properties of the impurity and tar- get particles, and the dielectrophoresis （DEP） separation and resistive pulse detection （RPS） zones in the channel are sequen- cially design. By theoretical simulation, the structure and size of the chip are optimized and defined. Also, the separation of 3μm polystyrene particles and detection and counting of the Pseud- okirchneriella subcapitata are experimentally achieved. Results show that the position of the particle collection channel arrange- ment has an important influence on particle collection. In addi- tion, the S/N of the detection of Pseudokirchneriella subcapitata is higher, which means high voltage does not impact the S/N. This research has some value for the development of fast detec- tion and analysis techonologies of the microfluidic chip-based portable devices for the single cell organism detection within complex samples.