Saliva-Based Diagnostic Tools on the Horizon. ‘Imagine this scenario at a dental checkup in your future: After settling you in the examination chair and fastening a paper bib around your neck, the dental assistant draws a sample of your saliva with a sterile pipette. Then, while your dentist performs your oral exam and the hygienist cleans your teeth, the dental assistant puts your saliva through a battery of diagnostic tests. By the end of your appointment, the tests are complete and your dentist reviews the results with you. Your dental checkup has morphed into a general health screening session.’
Integrated Microfluidic Platform for Oral Diagnostics (IMPOD), Amy E. Herr, Anson V. Hatch, William V. Giannobile, Daniel J. Throckmorton, Huu M. Tran, James S. Brennan and Anup K. Singh, Annals of the New York Academy of Sciences, doi: 10.1196/annals.1384.004. From the Abstract: While many point-of-care (POC) diagnostic methods have been developed for blood-borne analytes, development of saliva-based POC diagnostics is in its infancy. We have developed a portable microfluidic device for detection of potential biomarkers of periodontal disease in saliva. The device performs rapid microfluidic chip-based immunoassays (<3–10 min) with low sample volume requirements (10 µL) and appreciable sensitivity (nM–pM). Our microfluidic method facilitates hands-free saliva analysis by integrating sample pretreatment (filtering, enrichment, mixing) with electrophoretic immunoassays to quickly measure analyte concentrations in minimally pretreated saliva samples. The microfluidic chip has been integrated with miniaturized electronics, optical elements, such as diode lasers, fluid-handling components, and data acquisition software to develop a portable, self-contained device.
Microfluidic immunoassays as rapid saliva-based clinical diagnostics, Amy E. Herr, Anson V. Hatch, Daniel J. Throckmorton, Huu M. Tran, James S. Brennan, William V. Giannobile, and Anup K. Singh, Proceedings of the National Academy of Sciences (PNAS), doi: 10.1073/pnas.0607254104. From the Abstract: Here we report on a clinical POC diagnostic that enables rapid quantitation of an oral disease biomarker in human saliva by using a monolithic disposable cartridge designed to operate in a compact analytical instrument. Our microfluidic method facilitates hands-free saliva analysis by integrating sample pretreatment (filtering, enrichment, mixing) with electrophoretic immunoassays to quickly measure analyte concentrations in minimally pretreated saliva samples. Using 20 µl of saliva, we demonstrate rapid (<10 min) measurement of the collagen-cleaving enzyme matrix metalloproteinase-8 (MMP-8) in saliva from healthy and periodontally diseased subjects.