CN-121994897-A - Passive driving microcapsule motion color development method

Abstract

The invention relates to a passive driving microcapsule motion color development method, and belongs to the field of sensor detection. According to the method, sweat generated during movement of a human body drives the water-borne device to spontaneously generate electric potential, the electric potential is directly acted on microcapsule dispersion liquid to drive the directional movement of black-white particles in the microcapsule dispersion liquid, and visual color development response without an external power supply is realized. The method mainly comprises the steps of sweat-induced power generation, particle electrophoresis driving and ion concentration correlation color development. The sweat detection technology solves the problems that the existing sweat detection technology depends on an external power supply, the equipment is large in size and cannot realize real-time visual reading, and is mainly applied to the fields of real-time sweat electrolyte analysis in sports physiological monitoring, autonomous color development change of wearable medical equipment, passive sensing display integrated systems based on ion concentration gradients and the like.

Inventors

• ZHAO FEIJUN
• HUANG HONGLI

Assignees

• 桂林电子科技大学

Dates

Publication Date

20260508

Application Date

20251216

Claims (7)

1. 1. A passive driving microcapsule motion color development method is characterized by comprising the following steps of S1, constructing a water-voltage device, S2, preparing a color development microcapsule unit, S3, attaching the water-voltage device to a sweat-prone part of a human body, enabling sweat to flow into the water-voltage device to generate a potential difference, applying the potential difference to the color development microcapsule unit, S4, enabling the black-and-white particles to generate directional electrophoresis under the action of the potential difference, enabling the macroscopic optical state of the color development microcapsule unit to change, and S5, comparing the color development state of the color development microcapsule unit with a preset concentration-color development standard curve, and obtaining a detection result of specific ion concentration in sweat.
2. 2. The method according to claim 1, wherein step S1 comprises pre-treating the photovoltaic device, flushing the internal flow channels or porous structures with deionized water or a low concentration electrolyte solution, and placing the pre-treated photovoltaic device in a simulated sweat or buffer solution, and measuring the open circuit voltage and short circuit current until the output electrical signal is stable. The method according to claim 1, wherein step S2 comprises uniformly dispersing the electrophoresis microcapsule in a dispersion medium with matched dielectric constants to form microcapsule dispersion liquid, encapsulating the microcapsule dispersion liquid in a micro cavity with a transparent observation window and an electrode to form the color development microcapsule unit, and connecting the color development microcapsule unit with an output electrode of the photovoltaic device through a conductive circuit. The method according to claim 1, further comprising, prior to step S1.
3. 3. Ion-selective modification is carried out on the core porous material of the photovoltaic device, and functional molecules or polymers with selectivity to target ions are introduced. The method of claim 1, wherein step S5 is followed by separating the photovoltaic device and the color-developing microcapsule unit from the sweat sample, rinsing the flow channels of the photovoltaic device with a rinse buffer or deionized water, and applying a reverse electric field to the color-developing microcapsule unit to drive the black and white particles back to an initial dispersed state.
4. 4. The method according to claim 3, wherein the step S2 is followed by adding a surfactant or a stabilizer to the microcapsule dispersion liquid and standing at 25+ -5 ℃ for 30-60 minutes.
5. 5. The method of claim 1, wherein the core porous material of the photovoltaic device is one of a graphene oxide film, a carbon nitride nanosheet, an anodic aluminum oxide porous film or a nanocellulose aerogel, and the ion-selective modified functional molecule is one or more of a crown ether derivative, an ionophore or a two-dimensional material with ion screening effect. The method of claim 1, wherein the simulated sweat is an aqueous solution of pH 4.0-7.0 containing 0.1-100 mM NaCl, 0.1-50 mM KCl, 0.01-10 mM CaCl 2 , 0.1-20 mM lactic acid, and the wash buffer is one of deionized water, 0.1-10 mM HCl buffer, or 0.1-10 mM PBS buffer, and the pH is 5.0-8.0.
6. 6. The method of claim 6, wherein the surfactant is one of Tween-20, triton X-100 or sodium dodecyl sulfate, the mass percentage concentration of the surfactant in the dispersion liquid is 0.01% -1%, and the dispersion medium is one of silicone oil, dodecane, tetradecane or hexadecane.
7. 7. The method of claim 5, wherein the reverse electric field has an electric field strength of 0.1 to 10V/mm and an action time of 0.1 to 10 seconds.

Description

Passive driving microcapsule motion color development method [ Technical field ] The invention relates to a passive driving microcapsule motion color development method [ Background Art ] The hydro-voltaic effect (Hydrovoltaic effect) refers to a physical phenomenon that generates a potential difference through solid-liquid interface interactions when a fluid flows in a nanomaterial. The photovoltaic device developed based on the principle can directly convert kinetic energy and chemical energy of body fluids such as sweat continuously secreted by human bodies during movement into electric energy, and provides a novel passive energy supply scheme for a wearable sensing system. In the sweat physiological index detection field, electrolyte ion concentration is an important parameter reflecting the hydration state and neuromuscular function of the human body. The traditional detection method mainly depends on an electrochemical sensor, needs an external power supply to supply power and is matched with a complex signal processing circuit, and visual reading is difficult to achieve. While the display technology based on the electrophoresis microcapsule can provide visual feedback, the particle movement of the display technology usually needs to be driven by an external power supply, and the system integration level and the energy efficiency are low. The existing detection system powered by an external battery needs to be subjected to complicated links such as power management, signal conversion and display driving. The sensing module needs a certain initialization time and a certain calibration flow, has higher overall power consumption, needs data calculation and transmission, and is difficult to realize an ideal effect for the instant detection and the visualization application of a sport field. In the prior art, the scheme combining the photovoltaic power generation and the sensing is mainly to intermittently supply power to the traditional circuit through the energy storage element, and the problems that the energy conversion efficiency is low, the response speed is low, the direct electrophoretic driving of particles cannot be realized, and the system complexity and the reliability are insufficient due to the introduction of the electronic element still exist. [ Summary of the invention ] The invention aims to provide a passive driving microcapsule motion color development method, which solves the problems that the existing sweat detection technology depends on an external power supply, has low system integration level and cannot realize real-time visual reading. The technical scheme of the invention is as follows: The invention relates to a passive driving microcapsule motion color development method, which comprises the following implementation steps: (1) The construction method of the photovoltaic device comprises the steps of selecting a porous photovoltaic material with ion selectivity as a core power generation unit, and constructing a miniature photovoltaic device capable of spontaneously generating electric potential by utilizing sweat, wherein the construction method of the photovoltaic device comprises the following steps: (1.1) pretreatment of a photovoltaic device: The prepared water-based photovoltaic device is taken to check the conductivity and structural integrity of the electrode, deionized water or low-concentration electrolyte solution is used for flushing the internal flow passage or porous structure of the device so as to remove the residual impurities in the preparation process; (1.2) optimization of device performance: placing the pretreated water-based photovoltaic device in simulated sweat or buffer solution, driving liquid to flow through the device by applying small external force, or standing to fully infiltrate the device, and measuring the open-circuit voltage and short-circuit current of the device until the output electric signal is stable, thus obtaining the water-based photovoltaic device capable of being used immediately; (2) Collecting and preprocessing sweat samples: Taking sweat secreted naturally during human body exercise, or using the prepared simulated sweat as a sample to be tested, and preserving for later use; (3) Sweat drives the color reaction: (3.1) pretreatment: taking the activated water-voltage device in the step (1), and correctly connecting an output electrode of the activated water-voltage device with the microcapsule color development unit prepared in the step (2) to form a complete detection loop; (3.2) reaction: and (3) contacting the liquid inlet or the functional surface of the connected photovoltaic device with the sweat sample in the step (2) to enable sweat to continuously flow into and drive the device, reacting for 30-300 seconds at room temperature (15-35 ℃) and enabling the photovoltaic device to spontaneously generate a potential difference of 0.1-5.0V based on sweat flow, directly applying the potential to a microcapsule color development u