Biomedical Science Technique – API Strips

CONTENT AUTHORS:

Malgorzata Rekas and Marilena Ioannou

LEVEL:

College, University, Specialist Biomedical


OER FEATURES: (bundle of 9 resources)

WATCH THE FIRST OF 3 VIDEOS NOW!

PART 1 VIDEO

PART 1 TRANSCRIPT in PDF Form

PART 2 VIDEO

PART 2 TRANSCRIPT in Word

PART 2 TRANSCRIPT PDF

PART 3 VIDEO

PART 3 TRANSCRIPT PDF

SELF TEST QUIZ WORD FORMAT

SELF TEST QUIZ PDF FORMAT


OER DESCRIPTION:

In the biomedical science laboratory, quick screening of bacteria can be carried out using API strips. The strips are commercially available and allow for the rapid identification of a range of bacterial species. The plastic strip contains a number of wells or cupules which contain different biochemical tests, to which, bacteria will react differently. The results are visible as colour changes.

The strip is set up by preparing a suspension of the bacteria of interest, and transferring samples aseptically to each of the wells. Some of the wells have oil added to prevent the access of oxygen and mimic anaerobic conditions, which some bacteria prefer. The strip is then incubated for a short period of time and the results can be interpreted.

These three videos (and accompanying transcripts) provide an introduction to using API strips and how to interpret the results. A quiz can test the learner’s understanding.

If you are a lecturer or trainer, you can download these materials onto your own learning platform, and embed the quiz questions as a formative test for your students.

Biomedical Science Technique – Making a Bacterial Suspension


CONTENT AUTHORS:

Marilena Ioannou

LEVEL:

College, University, Specialist Biomedical


OER FEATURES: (bundle of 2 resources)

WATCH THE VIDEO NOW!

PDF TRANSCRIPT OF THE VIDEO


OER DESCRIPTION:

This video was made several years ago but is still a good demonstration of how to prepare a bacterial suspension using asceptic techniques. Marilena was a microbiologist in the NHS for many years, and is a member of the IBMS and relevant professional bodies. She has produced many open educational resources – OERs – over the years, as part of VAL (Virtual Analytical Laboratory) and this project Biology Courses. She is a star!

The VAL website no longer receives any technical support, so we are worried that it may eventually die, hence we are putting all the resources on YouTube and linking them to this website 🙂

Microbiology Technique – Immunofluorescence Bacterial Detection

CONTENT AUTHORS:

Malgorzata Rekas and Marilena Ioannou

LEVEL:

College, University, Specialist Biomedical


OER FEATURES: (bundle of 5 resources)

Biomedical science resources: Video


(http://www.youtube.com/watch?v=pftlio12im0&feature=plcp)

Transcript of Immunofluorescence Video (DOC)

Transcript of Immunofluorescence Video (PDF)

Multiple Choice Questions on Immunofluorescence (DOC)

Multiple Choice Questions on Immunofluorescence (PDF)

 

OER DESCRIPTION:

In the biomedical science laboratory, routine screening and detection of common diseases can place a burden on the laboratory as there can be vast numbers of patient samples to process. Sexually transmitted diseases are widely prevalent in society and infections such as that caused by Neisseria gonorrhoeae (N. gonorrhoeae) can affect the reproductive organs, rectum and throat. The infection can also be asymptomatic – meaning it does not present any symptoms – so an individual may be unaware they have the infection. But problems can manifest in later life for example causing infertility, ectopic pregnancy and other complications (1).

So, accurate and rapid screening of patient samples is necessary, and a simple immunofluorescence procedure is widely used to detect N. gonorrhoeae. In previous years, N. gonorrhoeae would have been identified using a Gram stain, but immunofluorescence has been demonstrated to be much more specific and sensitive, thus is a well used technique today. However, other high-throughput automated detection methods are being developed.

A bacterial colony is grown on an agar plate, and a small sample placed on a mono-spot slide. A small volume of immunofluorescence reagent is placed on the sample. Essentially the reagent is a fluorescent dye (e.g. FITC fluorescein isothiocyanate) bound to an antibody. The antibody binds to bacterial antigen on the N. gonorrhoeae, so the presence of fluorescence (a green colour) under the microscope indicates the presence of bacteria.

The simple technique takes around 20 minutes and the slide is viewed with a fluorescent microscope to complete the test. This is a typical microbiology technique performed in biomedical science laboratories to determine the presence of N. gonorrhoeae in patient samples.

(1). Centres for Disease Control and Prevention, US (2002). Screening Tests to Detect Chlamydia trachomatis and Neisseria gonorrhoeae Infections. Morbidity and Mortality Weekly Report , October 18, 2002 / Vol. 51 / No. RR-15. Available: http://www.cdc.gov/mmwr/pdf/rr/rr5115.pdf