Microfluidic Platform with In-Chip Electrophoresis Coupled to Mass Spectrometry for Monitoring Neurochemical Release from Nerve Cells.
Chemical stimulus-induced neurotransmitter release from neuronal cells is well-documented. However, the dynamic changes in neurochemical release remain to be fully explored. In this work, a three-layered microfluidic chip was fabricated and evaluated for studying the dynamics of neurotransmitter release from PC-12 cells. The chip features integration of a nanoliter sized chamber for cell perfusion, pneumatic pressure valves for fluidic control, a microfluidic channel for electrophoretic separation, and a nanoelectrospray emitter for ionization in MS detection. Deploying this platform, a microchip electrophoresis-mass spectrometric method (MCE-MS) was developed to simultaneously quantify important neurotransmitters, including dopamine (DA), serotonin (5-HT), aspartic acid (Asp), and glutamic acid (Glu) without need for labeling or enrichment. Monitoring neurotransmitter release from PC-12 cells exposed to KCl (or alcohol) revealed that all four neurotransmitters investigated were released. Two release patterns were observed, one for the two monoamine neurotransmitters (i.e., DA and 5-HT) and another for the two amino acid neurotransmitters. Release dynamics for the two monoamine neurotransmitters was significantly different. The cells released DA most quickly and heavily in response to the stimulation. After exposure to the chemical stimulus for 4 min, the DA level in the perfusate from the cells was 86% lower than that at the beginning. Very interestingly, the cells started to release 5-HT in large quantities when they stopped releasing DA. These results suggest that DA and 5-HT are packaged into different vesicle pools and they are mobilized differently in response to chemical stimuli. The microfluidic platform proposed is proven useful for monitoring cellular release in biological studies.
Department of Chemistry and Biochemistry, Jackson State University , 1400 Lynch Street, Jackson, Mississippi 39217, United States.|Wuhan Yaogu Bio-tech Company, Ltd. , Wuhan 430075, China.
Xiangtang
X
Li
Wuhan Yaogu Bio-tech Company, Ltd. , Wuhan 430075, China.|Zhongnan Hospital, Wuhan University , Wuhan 430071, China.
Hankun
H
Hu
College of Chemistry and Chemical Engineering, Guangxi Normal University , Guilin 51004, China.
Shulin
S
Zhao
Department of Chemistry and Biochemistry, Jackson State University , 1400 Lynch Street, Jackson, Mississippi 39217, United States.|Wuhan Yaogu Bio-tech Company, Ltd. , Wuhan 430075, China.
Yi-Ming
YM
Liu
D000818:Animals; D001224:Aspartic Acid / Q000032:analysis; D004298:Dopamine / Q000032:analysis; D004586:Electrophoresis; D018698:Glutamic Acid / Q000032:analysis; D056656:Lab-On-A-Chip Devices; D044085:Microfluidics / Q000295:instrumentation; D049329:Nanostructures / Q000737:chemistry; D009474:Neurons / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D018377:Neurotransmitter Agents / Q000032:analysis*; D016716:PC12 Cells; D011189:Potassium Chloride / Q000494:pharmacology; D051381:Rats; D012701:Serotonin / Q000032:analysis; D021241:Spectrometry, Mass, Electrospray Ionization
D018377:Neurotransmitter Agents; D001224:Aspartic Acid; D012701:Serotonin; D018698:Glutamic Acid; D011189:Potassium Chloride; D004298:Dopamine