Chemo-Mechanical and Chemo-Structural pH-Feedback Mechanisms to Program Transient and Autonomous Self-Assembling Systems

在前一个资助阶段的基础上，我们设想了在均匀溶液中具有瞬态pH状态的pH反馈系统，并将其与各种pH可切换的自组装体相结合，以在自主系统中对它们进行自我调节寿命的编程，该提案针对主动反馈机制以及自主，化学燃料，非平衡软物质和自组装系统的设计的下一步。 因此，这一提议超越了均匀溶液中的化学反馈，旨在开发和定量理解可推广的、自我调节的、耦合的化学-X pH反馈机制： 化学机械pH反馈系统基于pH调节酶（具有pH依赖性活性分布），其嵌入具有pH依赖性门控效应（底物扩散）的pH响应性核壳胶体中以自调节酶活性。 （二） 化学-结构pH反馈系统是基于嵌入共组装核-壳胶体中的pH调节酶级联，其特征在于pH依赖性共组装行为，并且其中形成的共组装体编码其自身的破坏。这将产生新的系统特征，包括（a）具有受控滞后时间和寿命的瞬时pH曲线，（B）可以通过向包埋的酶提供真正的休眠区域而被重新激活的pH曲线，以及（c）通过滞后效应、反应/扩散时间尺度的受控同步的振荡系统，和由化学机械反馈施加的时间控制的自门控效应以及时间编排的自调节化学机械反馈。这些使能概念允许朝向自主动态材料系统、产生自我调节和时间编程记忆功能的进步。我们的目标是研究这种行为的新型自擦除二肽水凝胶，并展示其用于微流控回路中的流体引导。特别的目的是找到在溶胶-凝胶-溶胶系统中的滞后和寿命的正交编程的途径，并且在凝胶化发生之前利用受控的滞后时间以允许前体受控地分布到分支通道网络中以模拟复杂血管网络中的血流阻断。

Building on the preceding funding phase, where we conceived pH-feedback systems with transient pH-states in homogeneous solution, and coupled them to a diverse range of pH-switchable self-assemblies to program them with self-regulating lifetimes in autonomous systems, this proposal targets the next steps in terms of active feedback mechanisms and in the design of autonomous, chemically fuelled, non-equilibrium soft matter and self-assembly systems. This proposal hence goes beyond chemical feedback in homogeneous solution and aims to develop and quantitatively understand generalizable, self-regulating, coupled chemo-X pH-feedback mechanisms:(i) chemo-mechanical pH-feedback systems are based on pH-modulating enzymes (with pH-dependent activity profile) as embedded in pH-responsive core-shell colloids with pH-dependent gating effects (substrat diffusion) to self-regulate the enzymatic activity. (ii) chemo-structural pH-feedback system are based on pH-modulating enzyme cascades as embedded in co-assembling core-shell colloids, featuring pH-dependent co-assembly behavior, and in which a formed co-assembly encodes its own destruction. This will give rise to new systems features, including (a) transient pH-profiles with controlled lag times and lifetimes, (b) pH-profiles that can be reactivated by providing truly dormant areas to the embedded enzymes, and (c) oscillating systems by controlled synchronization of hysteresis effects, reaction/diffusion timescales, and temporally controlled self-gating effects imposed by chemo-mechanical feedback as well as temporally orchestrated self-regulating chemo-structural feedback.These enabling concepts allow advancements toward autonomously dynamic material systems, spawning self-regulation and time-programmed memory functions. We aim to investigate this behavior for new types of self-erasing dipeptide hydrogels and showcase their use for fluidic guidance in microfluidic circuits. Particular aims are to find pathways towards an orthogonal programming of lag and life times in sol-gel-sol systems, and to exploit controlled lag times before gelation occurs to allow controlled distribution of precursors into branching channel networks to mimic blood flow blocking in complex vascular networks.