A buccal swab, also known as a buccal smear or a cheek swab, is one of the fastest and most common ways for forensic pathologists to establish or refute a link between a suspect and a crime scene.
This is accomplished by comparing touch DNA evidence from the crime scene with reference samples (also known as elimination samples) of buccal cells collected from various suspects. When there’s a match, investigators can undoubtedly link a suspect to the scene of a crime.
Many law enforcement facilities prefer buccal swabbing to other sample collection methods because it is fast, non-invasive, relatively comfortable, and can yield larger sample sizes than other collection methods. The first step in effective buccal swab sample collection is to make sure you’ve got the right tools on hand.
Build a Buccal Swab Collection Kit
Your department’s buccal swab collection kit doesn’t have to be fancy, but it should contain everything an individual would need in order to conduct and transport a buccal smear sample. Generally, buccal swab kits should contain the following:
- Two sterile swabs with cotton, foam, or flocked tips
- Two pairs of gloves
- A surgical mask
- Dry transport tubes or sterile collection envelopes
- A few strips of evidence tape
- Swabbing instructions
- Consent form (if required by jurisdiction)
- Clean pen
How to Collect a Buccal Swab Sample
Buccal swabbing is relatively convenient because it generally doesn’t require a medically trained professional. In fact, with some simple training, almost anyone can collect a buccal swab sample for forensic analysis. Here's how:
- Verify that the subject’s mouth is empty
- Wash or sanitize hands then put on gloves and mask
- Choose a sterile cotton, foam, or flocked swab
- Carefully remove swab from package
- Avoid touching swab tip with gloves or against any surface
- Have the subject open his or her mouth and immediately bring swab tip to inside of cheek
- Gently rub and rotate swab along the inside of the cheek for 5-10 seconds, ensuring that the entire swab-tip has made contact with the cheek
- Immediately remove swab, being careful not to touch swab tip against teeth, lips, or other surface
- Place swab directly into dry transport tube or collection envelope
- Label the tube or envelope with identifying information
- Use evidence tape to seal outer packaging
- Initial and date for chain of custody verification
- Store swab at room temperature or transfer to freezer until testing
Different Types of Buccal Swabs
Not all buccal swabs are created equal. To build a custom buccal swab collection kit specific to the needs of your department, speak with your lab manager to determine the requirements or collection priorities of your lab.
Sterile Foam Tipped Buccal Swabs
Due to their high particle collection capacity and soft tips, medical grade foam tipped swabs are generally the most popular swab-type for buccal cell collection. Foam tipped swabs can range in size from tiny (to minimize subject discomfort) to large (for high article collection capacity). Here are a few of the most popular Puritan foam swabs for buccal cell collection:
- Large Round DNA Free Foam Tipped Swab
- Foam Tipped Applicator Swab with Hollow Polystyrene Shaft
- Small Rectangular Foam Tipped Swab With Polypropylene Handle
Sterile Flocked Buccal Swabs
Because of their superior collection and elution properties, flocked swabs are quickly gaining popularity for buccal cell collection. The patented flocking pattern of Puritan’s flocked swabs traps more specimen within its propriety micro-channels than traditional swabs. Here are a few of our favorites for buccal smear collection:
- DNA Free, Ultra Flocked Swab with Transport Tube
- HydraFlock® Flocked Swab, Standard Tip
- HydraFlock® Flocked Swab, Elongated Tip
Sterile Cotton Tipped Buccal Swabs
Finally, due to their versatility and affordability, cotton-tipped swabs are also a popular choice for police department forensic labs. Here are a few of our most popular for buccal cell collection:
- DNA Free Cotton Tipped Applicator
- DNA Free Cotton Tipped Applicators with Dry Transport Tube
- DNA Controlled Cotton Tipped Applicator with Transport Tube
Want to learn more about how to collect a buccal cell sample for forensic analysis, or which swabs to choose for your buccal swab collection kit? Contact one of our knowledgeable product specialists today.
Giamanco, Chantel Marie. Collecting a Buccal Swab – An Art or a Cinch? Forensic Scientist Human Identification Technologies, Inc. Retrieved August 19 from http://www.hitdna.com/images/PDFs/publications/Taking%20a%20Buccal%20Swab.pdf
Collection Techniques. DNA Analyst Training. NFSTC Science Serving Justice®. Retrieved August 19 from http://www.nfstc.org/pdi/Subject01/pdi_s01_m01_05_a.htm.
Schiro G. Collection and Preservation of Evidence. In: Muth AS, editor. Forensic Medicine Sourcebook. Detroit: Omnigraphics, 1999; 45-59. Retrieved August 19 from http://www.forensicscienceresources.com/CAPE3.htm