The present invention provides a device for detecting an analyte in a sample, including a chamber for receiving a testing element, where the testing element has a first position and a second position in the chamber; the testing element is not in contact with a fluid sample when the testing element is located in the first position, and the testing element is in contact with a fluid sample when the testing element is located in the second position.

Disclosed is a method for preparing a tear diluent, and provided are a tear sample eluent and a tear sample collection and treating apparatus. A small-volume tear sample can be stably collected using an absorbent material, and a substance to be tested of the sample can be stably released after elution using the sample eluent provided in the present disclosure.

An absorbent, a preparation method therefor and use thereof are provided. The absorbent has a liquid channel, and the liquid channel has a low-tortuous porous structure. The absorbent can realize fast and large-scale absorption of various liquids without consuming external energy and not requiring additional apparatuses when in use. The absorbent can be used for efficient, safe and comfortable medical sampling and can also be used for recovery of various liquids.