Method for automatic determination of sample

A method for analyzing a substance, comprising a supplying step and an analyzing step,

• the supplying step comprising the steps of:
• supplying a sample suspected of containing the substance to be analyzed to a reaction system by a supplying means comprising a transparent region composed of a transparent material, wherein the sample is selected from the group consisting of whole blood, a serum, and plasma,
• irradiating the transparent region with light, and
• measuring an optical intensity T of a transmitted light from the transparent region,
• the analyzing step comprising the steps of:
• reacting a reagent for detecting the substance with the sample in the reaction system, and
• analyzing a signal derived from a product obtained by the reaction,
• wherein the supplying means is one in which a tip comprising the transparent region is mounted, or a tube or a channel comprising the transparent region, and the transparent region exhibits a lens effect that an optical intensity when plasma or a serum is aspirated into the transparent region is higher than an optical intensity when no sample is aspirated into the transparent region, and
• wherein after the measuring step in the supplying step, the supplying step further includes the steps of:
• (A) comparing the optical intensity T with previously determined threshold a between an optical intensity when plasma or a serum is aspirated into the supplying means and an optical intensity when no sample is aspirated into the supplying means, and with previously determined threshold b between an optical intensity when no sample is aspirated into the supplying means and an optical intensity when whole blood is aspirated into the supplying means,
• (B′) determining that, when the optical intensity T of the sample is higher than the threshold a, the sample is judged as plasma or a serum;
• when the optical intensity thereof is lower than the threshold b, the following step (C) is carried out;
• and when the optical intensity thereof is between the threshold a and the threshold b, the following step (D) is carried out,
• (C) diluting the sample, and comparing the difference “T′−T” between an optical intensity T′ measured under the same conditions and the optical intensity T, with previously determined threshold c between the difference “T′−T” when a sample is a chyle plasma or serum sample and the difference “T′−T” when a sample is whole blood, to determine that, when the “T′−T” is larger than the threshold c, the sample is judged as a chyle plasma or serum sample;
• and when the difference “T′−T” is not more than the threshold c, the sample is judged as whole blood, and
• (D) diluting the sample, and comparing the difference “T′−T” between the optical intensity T′ measured under the same conditions and the optical intensity T, with previously determined threshold d between the difference “T′−T” when a sample is a chyle plasma or serum sample and the difference “T′−T” when no sample is aspirated into the supplying means, to determine that, when the “T′−T” is larger than the threshold d, the sample is judged as a chyle plasma or serum sample;
• and when the difference “T′−T” is not more than the threshold d, it is judged that no sample is aspirated into the supplying means.