Microengineered Lollipop for Patient-Centric Saliva Collection - PROJECT SUMMARY/ABSTRACT Oral samples for respiratory disease diagnosis are essential as certain bacterial and viral infections can lead to serious long-term conditions when left untreated. However, accessing these samples is challenging in some cases, such as in young children and remote patients where telemedicine is essential. Currently, oral sample collection relies on traditional naso- and pharyngeal swabs that are difficult, painful, and traumatic for young children and potentially result in delayed access to diagnostic results, leading to negative outcomes. We designed a novel, micro-engineered, lollipop-inspired platform (LolliTest) to improve on at-home oral sample collection capabilities. The LolliTest was designed with two key features, (1) functionalized open microchannels for pathogen capture and concentration and (2) time-controlled flavoring release to make the platform more patient-centric. The use of open microfluidics (i.e., microfabricated channels without a ceiling) is advantageous as it allows optimal saliva exchange and access to the capture areas while preventing mechanical abrasion by the tongue or other surfaces of the mouth, which could dislodge captured bacteria. The time-controlled flavoring release enables the user to intuitively know how long to use the LolliTest device, eliminating the need for complex instructions in a home setting. To establish the platform, we propose two specific aims. Aim 1 will optimize the LolliTest platform to capture known oral commensal microorganisms in healthy subjects. This enables safe testing and development cycles with simple access to human subjects who have a range of bacterial concentrations in their saliva. We will specifically adapt and optimize key features of the LolliTest, such as the open-fluidic functionalized capture channels and the time-tailored flavor-release function, to enable the capture of a selected microorganism in concentration commensurate with typical pathogens. This aim also allows iteration to improve ease-of-use and subject experience based on user surveys. Aim 2 will demonstrate functionality of the LolliTest platform to capture and detect Group A Streptococcus (GAS) in vitro and in a small- scale clinical study to demonstrate the potential of the platform for acquisition of samples from children in the clinic. We will compare results of the LolliTest sampling (followed by real time-polymerase chain reaction) with conventional pharyngeal swabs and clinical analysis, validating the ability of the LolliTest to determine if a patient is positive or negative for GAS. With deliberate design to maximize collection performance from saliva sampling, our long-term vision is that our LolliTest platform will achieve better sensitivity and specificity than can be obtained with current biospecimen collection techniques, while providing a platform that is preferred by patients and usable in home settings. Ultimately, the LolliTest has the potential to make saliva sampling a new gold standard for respiratory disease diagnostics.
