Final answer:
Blood spot collection on filter paper is a biochemical technique used to preserve blood samples for analysis or assay testing in medical and molecular biology fields. Techniques include capillary action for blood collection, blotting for DNA or RNA analysis, and lateral flow tests for rapid diagnostics.
Step-by-step explanation:
Blood spot collection on filter paper is a technique used in medical analysis that entails absorbing blood on a special kind of filter paper for laboratory testing. This method is typically used in collecting blood for various assays and tests because the filter paper can preserve the blood sample for a significant amount of time. For instance, the blood may be collected via capillary action into a fine glass tube or directly spotted onto sterile filter paper.
In laboratory settings, one might use sterile blank filter paper disks and soak them in different solutions, such as disinfectants or antiseptics, for testing their efficacy. Subsequently, the filter paper is placed on an agar plate to assess microbial growth inhibition. In molecular biology, a similar process is used for blotting buffer transfer during procedures like Southern or Northern blotting, where DNA or RNA is transferred to a nylon filter.
Furthermore, blood smears are used to evaluate the cellular components of blood, whereby a drop of blood is spread thinly across a glass slide to form a film with a feathered edge. This is critical for microscopic examination of blood, as this technique allows for individual cells to be distinguished. In addition, lateral flow tests, which might use urine instead of blood, operate on the same principle of capillary action, where reagents are activated by the test fluid and results are indicated by color change.