UV-visible absorption detection system based on micro-fluidic chip and detection method thereof

Abstract

The application discloses a UV-visible absorption detection system based on a micro-fluidic chip and a detection method thereof. The UV-visible absorption detection system comprises a chip substrate, a micro-channel formed on the chip substrate and a UV absorption detector integrated on the chip substrate, wherein the micro-channel comprises a detection channel, and rays generated by the UV absorption detector are parallel to the extending direction of the detection channel. A light source of the UV absorption detector emits in and out in the horizontal direction of the chip, namely, in the direction parallel to the channel of the chip, so that the problem of short absorption optical path is solved; a UV-visible absorption detection operation unit is simple, low in detection cost and strong in university; the UV-visible absorption detector is integrated into the micro-fluidic chip, so that detection convenience is realized, and the quantity of the consumed solution can reach several or dozens of micro-liters. Compared with a traditional UV-visible absorption detection system, the detection method provided by the invention is greatly lowered in sample consumption, and has significance on detection of ions, micromolecules and the like in the field of environmental water or food.

Description

technical field [0001] The application belongs to the field of microfluidic chip laboratory detection, and in particular relates to a detection system integrating an ultraviolet-visible absorber into a microfluidic chip, which can be used for ion or small molecule detection in the environment or food fields. Background technique [0002] Microfluidic chip laboratory (Lab on Chip) or Micro Total Analysis System (Micro Total Analysis System, or microTAS) refers to the basic A technology in which operating units are integrated or basically integrated on a chip of several square centimeters to complete different biological or chemical reaction processes and analyze their products. It achieves chemical analysis and detection through the intersection of analytical chemistry, micro-electromechanical processing (MEMS), computer, electronics, material science and biology, medicine and engineering, that is, to realize the overall miniaturization, automation, and integration from sampl...

AI Technical Summary

Problems solved by technology

Among them, laser-induced fluorescence detection has high sensitivity and is suitable for the detection of various substances in chip microchannels. However, many substances have no fluorescent properties and require fluorescent labeling. In many experiments, it is impossible to ensure whether the properties of the tested substances after labeling Changes will directly affect the reliability of the experimental results, and the application is limited. The interface between the mass spectrometer detector and the microfluidic chip is difficult. In comparison, the ultraviolet-visible absorption detection operation unit is simple, the detection cost is low, and the versatility Strong, if it is integrated into a microfluidic chip, it can realize portable detection, which is of great significance to the detection of heavy metals or small molecules in environmental water or food fields.

[0004] The principle of ultraviolet-visible absorption is Lambert-Beer's law, and the absorbance is proportional to the absorption path. For high-concentration samples, a chip with an ordinary size can meet the detection requirements, but for low-concentration samples, it is necessary to design and manufacture a chip with a long pathlength. This increases the processing difficulty of the chip and increases the amount of detection samples. It can be seen that it is difficult to achieve long optical path detection in the direction perpendicular to the chip channel.

In addition, commonly used chip materials such as glass and plastic have a large absorption of ultraviolet light and are not suitable for ultraviolet detection, while chip materials such as quartz and PDMS have little ultraviolet absorption and are ideal materials for ultraviolet absorption photometric detection.

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