title: Colorimetric Assay for the Detection of Typical Biomarkers for Periodontitis Using a Magnetic Nanoparticle Biosensor.
abstract: Periodontitis is a chronic disease which affects at least 10% of the population. If untreated, periodontitis can lead to teeth loss. Unfortunately, current diagnostic tests are limited in their sensitivity and specificity. In this study, a novel multiplex hand-held colorimetric diagnostic biosensor, using two typical inflammatory salivary biomarkers, Human Neutrophil Elastase (HNE) and Cathepsin-G, was constructed as proof of concept to potentially detect periodontitis. The biosensing method was based on the measurement of proteolytic activity using specific proteases probes. These probes consist of specific proteases substrates covalently bound to a magnetic bead from one end and to the gold sensor surface by the other end. When intact, this renders the golden sensor black. Upon proteolysis, the cleaved magnetic beads will be attracted by an external magnet revealing the golden color of the sensor surface observable by the naked eye. The biosensor was capable of specific and quantitative detection of HNE and Cathepsin-G in solution and in spiked saliva samples with a lower detection limit of 1 pg/mL and 100 fg/mL for HNE and Cathepsin-G, respectively. Examination of periodontitis patients' sample and a healthy control showed the potential of the multiplex biosensor to detect the presence of HNE and Cathepsin-G activity in situ. This approach is anticipated to be a useful biochip array amenable to low-cost point-of-care devices.
authors.affiliation: Centre of Biomedical Engineering, Cranfield University , Cranfield, Bedfordshire MK43 0AL, U.K.|Department of Chemistry, Alfasal University , Al Zahrawi Street, Al Maather, Al Takhassusi Road, Riyadh 11533, Kingdom of Saudi Arabia.
authors.forename: Shayalini
authors.initials: S
authors.lastname: Wignarajah
authors.affiliation: Department of Pharmaceutical Sciences, Faculty of Pharmacy, The University of Jordan , Amman, 11942 Jordan.
authors.forename: Ghadeer A R Y
authors.initials: GA
authors.lastname: Suaifan
authors.affiliation: Department of Periodontology, Academic Centre for Dentistry Amsterdam, University of Amsterdam and VU University Amsterdam , Gustav Mahlerlaan 3004, 1081 LA Amsterdam, The Netherlands.
authors.forename: Sergio
authors.initials: S
authors.lastname: Bizzarro
authors.affiliation: Department of Oral Biochemistry, Academic Centre for Dentistry Amsterdam, University of Amsterdam and VU University Amsterdam , Gustav Mahlerlaan 3004, 1081 LA Amsterdam, The Netherlands.
authors.forename: Floris J
authors.initials: FJ
authors.lastname: Bikker
authors.affiliation: Department of Oral Biochemistry, Academic Centre for Dentistry Amsterdam, University of Amsterdam and VU University Amsterdam , Gustav Mahlerlaan 3004, 1081 LA Amsterdam, The Netherlands.|Department of Medical Microbiology and Infectious Diseases, Erasmus Medical Center , Wytemaweg 80, 3015 CE Rotterdam, The Netherlands.
authors.forename: Wendy E
authors.initials: WE
authors.lastname: Kaman
authors.affiliation: Department of Chemistry, Alfasal University , Al Zahrawi Street, Al Maather, Al Takhassusi Road, Riyadh 11533, Kingdom of Saudi Arabia.
authors.forename: Mohammed
authors.initials: M
authors.lastname: Zourob
mesh_terms: D015415:Biomarkers / Q000032:analysis; D015374:Biosensing Techniques; D056649:Cathepsin G / Q000032:analysis* / Q000378:metabolism; D003124:Colorimetry / Q000379:methods*; D006801:Humans; D019272:Leukocyte Elastase / Q000032:analysis* / Q000378:metabolism; D058185:Magnetite Nanoparticles / Q000737:chemistry*; D010518:Periodontitis / Q000175:diagnosis* / Q000378:metabolism*
chemical_list: D015415:Biomarkers; D058185:Magnetite Nanoparticles; D056649:Cathepsin G; D019272:Leukocyte Elastase