What is the primary reason glass collection tubes are preferred for certain blood samples?

Glass collection tubes are preferred for certain blood samples primarily because glass has properties that can influence the blood sample in specific ways. One of the notable characteristics of glass is that it can create a less reactive surface compared to plastic tubes, which may help to reduce platelet activation. This is particularly important in tests where it is necessary to maintain the integrity of platelets, such as those used for coagulation studies.

When a blood sample comes into contact with materials that are more prone to activate platelets (like plastic), it can lead to premature clotting or inaccurate test results. Therefore, glass collection tubes, which do not have this effect, allow for a more accurate representation of the blood’s coagulation status and prevent interference with the testing process.

Other factors, such as ease of handling and cost-effectiveness, are indeed relevant in the use of collection tubes but they are secondary to the influence that the collection material has on the biological properties of the blood sample.