Bubble-free liquid core waveguide tube liquid feeding device based on centrifuging

Abstract

The invention provides a bubble-free liquid core waveguide tube liquid feeding device based on centrifuging. The device comprises a breathable micro pipeline arranged on a rotary disc of a centrifuging device, the two ends of the micro pipeline are each connected with a liquid storage pool, the two liquid storage pools are communicated, and an optical window is arranged at the end, away from the micro pipeline, of each liquid storage pool; the micro pipeline is linear, and one end of the micro pipeline points to a rotary shaft of the rotary disc; the liquid storage pool close to the rotary shaft is open, and the liquid storage pool away from the rotary shaft is closed; the micro pipeline is in a U type, the two ends of the micro pipeline are close to the rotary shaft of the rotary disc; the two liquid storage pools are open; the optical windows are special optical elements or interfaces formed by liquid; the micro pipeline is made from Teflon AF. The wall thickness of the micro pipeline is 50-500 micrometers; the initial liquid level of the liquid storage pool close to the rotary shaft is 5-50 mm; the rotating speed of the rotary disc of the centrifuging device is 100 rpm or above.

Description

technical field [0001] The invention relates to a sample feeding device, in particular to a bubble-free sample introducing device for an optical testing device or instrument. Background technique [0002] Teflon AF has a lower refractive index than water, so when a pipe made of Teflon AF is filled with water or an aqueous solution, the interface between water and Teflon AF can meet the conditions of total reflection, and conduct light incident at a certain angle like an optical fiber. capability to form so-called liquid-core waveguides. Because the liquid core waveguide has a strong light guiding ability, a longer optical path can be obtained in it, so as to realize the sensitization of various optical detection technologies based on the principles of emission, absorption, fluorescence, and scattering, which is very good. Application prospect. However, because the Teflon AF material itself is hydrophobic and aerophilic; and the diameter of the commonly used Teflon AF tube ...

AI Technical Summary

Problems solved by technology

However, because the Teflon AF material itself is hydrophobic and aerophilic; and the Teflon AF tube diameter usually used is relatively small, no more than 10mm, and the surface effect of hydrophobicity is more serious, so it is very easy to form air bubbles in the tube

Once the bubbles are formed, the total reflection phenomenon at this point will disappear, and the optical path will be interrupted, which will seriously affect the sensitivity and stability of optical measurement. This serious defect greatly limits its application.

[0003] Elimination of bubbles in the liquid can be done in a centrifugal manner: using the sample to increase the buoyancy of the bubbles under centrifugal conditions to remove large bubbles in the liquid, but for the microbubbles 14 in the rigid micropipe 12 that rotates around the axis of rotation 11 (see figure 1 Above), as the centrifugal force 15 increases, the air bubbles 14 in the rigid microchannel 12 are subjected to the centrifugal force of the solution 13, and the pressure increases sharply so that its volume is continuously compressed (see figure 1 Bottom), so the increase of the buoyancy of the bubble 14 is not obvious, and it is hindered by the space, so that the removal effect of the bubble 14 is poor under this condition, so the centrifugal method is rarely used in the rigid micropipe 12 for degassing

[0004] Another method to remove air bubbles in the liquid is the vacuum degassing method. Chinese patent 201310415459.3 proposes a negative pressure sampling device, which can eliminate the air bubbles in the liquid core waveguide while feeding the liquid, but each liquid core of the device Waveguides need to be equipped with a vacuum pump and several solenoid valves, and are controlled by a certain program, so the cost is high and the control is complicated, which is not conducive to improving the throughput and popularizing the use

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