Rapid Stain Identification of Human Blood (RSID-Blood)

Introduction: RSID is a primary binding assay that is very sensitive, reliable, and produces fast results. One advantage of the test is it can detect a sample size of 1µL. Another advantage is that there cannot be a High Dose Effect. The appearance of a pink line at the T-zone means a positive for human blood. A pink line at the C-zone means that the test is working properly. RSID-Blood test confirms human blood.

Materials: Positive Sample 8 eppendorf tubes (1.5)

Negative Sample Sharpee

Two Unknown Samples Rack

Micropipette (200µL, 20-100µL) Buffer

Vortex Runner

Centrifuge

4 RSID- Blood Cassettes

Procedure: Label the first four 1.5 eppendorf tubes with sample name, initials, and date.

Rapid Stain Identification of Human Blood (RSID-Blood)

- Obtain each sample and give detailed description of each sample. Provide measurements of sample and measurement of piece cut from sample.

- Tip: Find a good saturated (completely covered) stain and cut a somewhat larger piece from the stain (4mm) to help produce better results.

- As you transfer each sample into its proper eppendorf tube you must have someone initial each transfer. The initial means that the person is validating that the right sample is being placed into the right tube. This helps prevents mistakes from occurring.

- Pipette 200 µL of buffer into each of the sample tubes.

-Vortex each sample for two seconds to ensure that buffer is mixed with the sample. Then spin each sample with the centrifuge for two seconds to make sure the sample sinks to the bottom of the eppendorf tube.

Rapid Stain Identification of Human Blood (RSID-Blood)

- Let each sample incubate for one hour.

Tip: While waiting check your samples and see if the liquid has a brown color to it. This indicates that you have a good blood sample to help give you better results on the cassette.

- While waiting, obtain four new 1.5 eppendorf tubes and label each tube with sample name, initials, and date. Pipette 80 µL of runner into each eppendorf tube. Gather four RSID-Blood cassettes and label each with sample name, initials, date, and blood at the bottom of cassette.

- Tip: Place the matching sample name eppendorf tube containing the 80 µL of runner behind the matching sample name tube containing buffer and sample (like in the picture below). This helps to prevent confusion.

Rapid Stain Identification of Human Blood (RSID-Blood)

- After an hour of incubating, transfer 100 µL of the sample into the matching sample name eppendorf tube containing the 80µL of runner. A classmate must initial each transfer to ensure the mixture is going into the correct tube.

- After the transfers have been made vortex each of the sample for two seconds and then spin them for two seconds. Pipette 100 µL of each sample into the well of the RSID- Blood cassette with matching sample name. Record the results.