Institute of Optoelectronic Thin Film Devices and Technology, Key Laboratory of Optoelectronic Thin Film Devices and Technology of Tianjin, Nankai University, Tianjin 300350, China.
Nanoscale Horiz. 2020 Sep 1;5(9):1324-1331. doi: 10.1039/d0nh00348d. Epub 2020 Aug 4.
In a biological synapse, α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA) receptors mediate fast excitatory neurotransmission, whereas N-methyl-d-aspartate (NMDA) receptors trigger an enhanced memory effect; the complementary roles of AMPA and NMDA are essential in short-term plasticity (STP) to enhance memory effect (EME) transition. Herein, we report the design and fabrication of the first two-dimensional (2D) conjugated polymer (CP)-based synaptic transistor. The special design of the 2D CP with nanoscale-segregated 'polka dot'-structured crystalline phases and adjacent amorphous phases emulate the different receptors of NMDA and AMPA on the postsynaptic membrane for the first time. The synergistic effect of mixed receptors distinguishes STP and enhanced memory effect with a critical point, which regulates the threshold level of the enhanced memory effect induction. This effect has not been reported yet. The special structure avoids easy saturation of a single receptor with consecutively increased excitatory postsynaptic current (EPSC) in response to 1200 stimuli. Furthermore, the 2D P3HT synapse successfully emulates activity-dependent synaptic plasticity, such as metaplasticity and homeostatic plasticity, which are advanced forms of plasticity, allowing the self-adaptive ability of a synapse, but have rarely been reported.
在生物突触中，α-氨基-3-羟基-5-甲基-4-异恶唑丙酸（AMPA）受体介导快速兴奋性神经递质传递，而 N-甲基-D-天冬氨酸（NMDA）受体引发增强的记忆效应；AMPA 和 NMDA 的互补作用对于短期可塑性（STP）增强记忆效应（EME）转换至关重要。在这里，我们报告了第一个二维（2D）共轭聚合物（CP）基突触晶体管的设计和制造。2D CP 的特殊设计具有纳米级分离的“波尔卡圆点”结构的结晶相和相邻的非晶相，首次模拟了突触后膜上 NMDA 和 AMPA 不同的受体。混合受体的协同作用区分了短期可塑性和增强的记忆效应，具有临界点，调节增强记忆效应诱导的阈值水平。这种效应尚未被报道过。特殊的结构避免了由于连续增加的兴奋性突触后电流（EPSC）而导致单一受体容易饱和的情况，响应了 1200 个刺激。此外，2D P3HT 突触成功模拟了活性依赖性突触可塑性，如后效性和自稳态可塑性，这些都是高级形式的可塑性，允许突触具有自适应能力，但很少被报道。
