DNA Isolation from Buccal Swabs
Buccal swabs are a non-invasive way to collect human DNA samples. Several companies produce buccal swabs and each recommend varying collection methods; such as Puritan polyester tipped applicators (PN 25-806-2PD) recommends swabbing the inside of the cheek with two different swabs. Below is a protocol developed by Beckman Life Sciences PoP team members for specific customers and the data when the protocols were used with Puritian and Copan FLOQSwabs™ (PN 50E011E01). Both swabs were used to ensure that both brands can be extracted from using the same protocol.
Protocol:
Isolation of DNA from Buccal Swabs using DNAdvance Kit
DNA Extraction from Puritian and Copan FLOQSwabs™ Buccal Swabs
Puritan polyester swabs and Copan FLOQSwabs™ were wet on the tongue and then run ten times on each cheek of three healthy donors. In order to run both Puritan swabs in a single well, the volume of Lysis Buffer was increased to completely cover both swab heads. If the swab heads are not covered by Lysis Buffer, DNA yields are lower and less consistent. Subsequent reagents were scaled up to work with the larger volumes of Lysis Buffer.
Two Puritan polyester swabs resulted in greater than 1 µg of DNA with concentrations ranging from ~20-50 ng/µL (Table 1). A single Copan FLOQSwabs™ resulted in slightly less yield, with concentrations from ~10 – 25 ng/µL and total yield of greater than 450 ng (Table 1, Figure 1). Little protein contamination was seen, with 260/280 values of 1.6-1.7 (Table 1).
| Sample | Conc. (ng/µL) | Purity (260/280) | Yield (µg) |
|---|---|---|---|
| Copan FLOQSwabs™ 1 | 7.855 | 1.6 | 0.47 |
| Copan FLOQSwabs™ 2 | 24.91 | 1.6 | 1.5 |
| Copan FLOQSwabs™ 3 | 18.36 | 1.7 | 1.1 |
| Puritan 1 | 17.99 | 1.7 | 1.1 |
| Puritan 2 | 52.46 | 1.6 | 3.1 |
| Puritan 3 | 31.23 | 1.6 | 1.9 |
