A label-free terahertz attenuated total reflection technology platform for evaluating the response characteristics of responsive hydrogels

Abstract

The invention belongs to the technical field of terahertz biomedical detection, in particular relates to a terahertz attenuated total reflection technology platform for the label-free evaluation of responsive hydrogel response characteristics. The technical platform is composed of a total reflection prism, a hydrogel forming part and a cover plate, the hydrogel forming part is located on the surface of the total reflection prism and is embedded into a groove in the lower surface of the cover plate to form a reaction tank, the cover plate is further provided with a sample inlet and a sample outlet, and the sample inlet and the sample outlet are both communicated with a reaction tank through micro-channels. Methods of evaluating the responsive hydrogel responsiveness characteristics by usingthe technology platform are also provided. The technical platform can be directly polymerized into a hydrogel network on the surface of the total reflection prism to obtain the THz intrinsic signalsof hydrogel in a wide frequency spectrum range, the real-time and continuous characterization of the hydrogel is achieved, the interference of external environment changes is reduced, the accurate andrich data support is provided for optimization of a hydrogel system, and the detection flux can be improved.

Description

technical field [0001] The invention belongs to the technical field of terahertz biomedical detection, and in particular relates to a terahertz attenuated total reflection technology platform for evaluating the response characteristics of responsive hydrogels without marking. Background technique [0002] Terahertz (THz) waves refer to electromagnetic waves with a frequency of 0.1THz-10THz. Terahertz attenuated total reflection technology is to obtain the complex permittivity information of the sample within tens of microns on the surface of the prism through the evanescent wave generated when the wave is totally reflected on the surface of the prism. Since THz waves are extremely sensitive to water molecules (at room temperature water absorbs about 230cm at ITHz -1 ), slight changes in water content can cause significant THz signal changes. Therefore, the use of THz waves has the advantages of being able to detect weak intermolecular interactions, skeleton vibrations, and...

AI Technical Summary

Problems solved by technology

At present, the labeling characterization technology is mainly to characterize the swelling or depolymerization performance of the gel by encapsulating enzymology, nano gold, etc. Encapsulation molecules are used to indirectly characterize the change of crosslinking density during the gel response process. There are problems such as interference of encapsulation molecules with gel network crosslinking and uneven dispersion. It is difficult to truly restore the dynamic change process of gel network crosslinking state.

There are also defects in the label-free characterization technology of gels. For example, although atomic force microscopy can characterize the cross-linking density by measuring the viscoelasticity of the gel, and can obtain nanoscale structure information on the surface of the gel, this type of measurement is very difficult for operations, hardware, etc. The requirements are very high, and the cost is too high for general hydrogel characterization; the optical platform based on interferometry calculates the macroscopic volume change caused by the gel response process through the optical path difference of the gel film, and its limitation is that it strongly depends on the film The surface condition is sensitive to the change of the film tilt angle, resulting in poor measurement accuracy; the resolution of the electron microscope technology for directly observing the structural characteristics of the gel network is as high as 0.1-0.2nm, and the submicroscopic structure can be observed, but the sample preparation process is complicated, The equipment is expensive and requires professional operators; in addition, some studies have used the strong absorption characteristics of water in the THz band and the water content change characteristics of the responsive hydrogel and the characteristic reaction process of the target molecule to combine the responsive hydrogel modification with the THz ultrasonography. However, due to the need for pretreatment on the surface of the metamaterial chip, the operation is complicated and time-consuming, and this method can only obtain the relative change intensity of the terahertz signal and the fixed frequency band. It is difficult to accurately obtain the absolute value of the THz complex permittivity of the gel network in the wide THz band range

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