Department of Chemistry and Biomolecular Science, Clarkson University, Potsdam, New York 13699-5810, USA.
Anal Chem. 2010 Mar 1;82(5):1822-30. doi: 10.1021/ac902465v.
We monitored real-time in vivo levels of serotonin release in the digestive system of intact zebrafish embryos during early development (5 days postfertilization, dpf) using differential pulse voltammetry with implanted carbon fiber microelectrodes modified with carbon nanotubes dispersed in nafion. A detection limit of 1 nM, a linear range between 5 and 200 nM, and a sensitivity of 83.65 nA x microM(-1) were recorded. The microelectrodes were implanted at various locations in the intestine of zebrafish embryos. Serotonin levels of up to 29.9 (+/-1.13) nM were measured in vivo in normal physiological conditions. Measurements were performed in intact live embryos without additional perturbation beyond electrode insertion. The sensor was able to quantify pharmacological alterations in serotonin release and provide the longitudinal distribution of this neurotransmitter along the intestine with high spatial resolution. In the presence of fluvoxamine, a selective serotonin reuptake inhibitor (SSRI), concentrations of 54.1 (+/-1.05) nM were recorded while in the presence of p-chloro-phenylalanine (PCPA), a tryptophan hydroxylase inhibitor, the serotonin levels decreased to 7.2 (+/-0.45) nM. The variation of serotonin levels was correlated with immunohistochemical analysis. We have demonstrated the first use of electrochemical microsensors for in vivo monitoring of intestinal serotonin levels in intact zebrafish embryos.
我们使用植入式碳纤维微电极，该微电极表面修饰了分散在 Nafion 中的碳纳米管，通过差分脉冲伏安法，在斑马鱼胚胎早期发育（受精后 5 天，即 5 dpf）过程中，实时监测了消化系统中血清素的释放情况。记录到的检测限为 1 nM，线性范围在 5 到 200 nM 之间，灵敏度为 83.65 nA x microM(-1)。将微电极植入斑马鱼胚胎肠道的不同部位。在正常生理条件下，体内测量到的血清素水平高达 29.9(+/-1.13)nM。在不进行额外干扰的情况下，对完整的活体胚胎进行了测量，只需将电极插入即可。该传感器能够定量检测血清素释放的药理变化，并提供这种神经递质在肠道中的纵向分布，具有高空间分辨率。在氟伏沙明（一种选择性血清素再摄取抑制剂，SSRIs）存在的情况下，记录到的血清素浓度为 54.1(+/-1.05)nM，而在色氨酸羟化酶抑制剂对氯苯丙氨酸（PCPA）存在的情况下，血清素水平下降到 7.2(+/-0.45)nM。血清素水平的变化与免疫组织化学分析相关。我们首次展示了电化学微传感器在完整的斑马鱼胚胎中用于体内监测肠道血清素水平的应用。
