Direct drops are not feasible for the New Crown Antigen Test. The principle of the new crown antigen test lies in sampling through nasal swabs or throat swabs and allowing the collected samples to react with the reagents in an antigen-antibody reaction, and the results are obtained after sufficient reaction. If the nasal swab or throat swab is not mixed with the preservative solution in the sampling tube, and the preservative solution in the sampling tube is directly dripped onto the sample hole of the test card, it will not be possible to make the collected sample react with the test reagent, and even less accurate test results can be obtained. The test will fail due to errors in the operation process. The formal antigen testing procedure should be: mix the nasal swab or throat swab after sample collection with the preservation solution in the sampling tube thoroughly, then drop the preservation solution into the sample hole, wait for 15~30 minutes, and then check the test results.