At-home oral bacteria collection using a lollipop-based microfluidic device

Our previous work introduced the CandyCollect (1) a lollipop-inspired saliva collection device for respiratory disease diagnostics. Here, we performed the first human subjects study using this device to capture bacteria in saliva; we demonstrate that the CandyCollect device can be used to collect salivary bacteria from healthy adults using Streptococcus mutans and Staphylococcus aureus as proof-of-concept commensal bacteria. We enrolled 14 healthy adults in a nationwide (USA) remote study in which participants were sent study packages containing CandyCollect devices and traditional commercially available oral swabs and spit tubes. Participants sampled themselves at home, completed usability and user preference surveys, and mailed the samples back to our laboratory for analysis by qPCR. S. mutans and S. aureus are not universally present in all healthy adults (2-5). Our results showed that for participants in which a given bacterium (S. mutans or S. aureus) was detected in one or both of the commercially available methods, CandyCollect devices had a 100% concordance with those results. Furthermore, the CandyCollect device was ranked the highest preference sampling method among the three sampling methods by 26 participants surveyed. We also showed that the CandyCollect device has a shelf life of up to 1 year at room temperature, a storage period that is convenient for clinics or patients to keep the CandyCollect device and use it any time. Taken together, we have demonstrated that the CandyCollect is a user-friendly saliva collection tool that has the potential to be incorporated into diagnostic assays in clinic visits and telemedicine. ### Competing Interest Statement ABT has ownership in Stacks to the Future, LLC; ST: ownership in Stacks to the Future, LLC, Tasso, Inc., and Salus Discovery, LLC; and EB has ownership in Stacks to the Future, LLC, Tasso, Inc., and Salus Discovery, LLC and employment by Tasso, Inc. However, this research is not related to these companies.