title: A new point-of-care portable immunosensor for non-invasive assessment of oro-ileal transit time by oral fluid tauroursodeoxycholate measurement after its oral load.
abstract: A non-invasive test for oro-ileal transit time (OITT) evaluation was developed, based on the measurement of tauroursodeoxycholic acid (TUDCA) oral fluid concentration profile after its oral administration. Exploiting the fact that TUDCA is actively absorbed only in the ileum, OITT is measured as the time corresponding to TUDCA maximum oral fluid concentration (tmax). To measure oral fluid TUDCA concentration in a point-of-care setting, an ultrasensitive portable immunosensor was developed, based on a competitive chemiluminescent enzyme immunoassay (CL-EIA), using immobilized anti-TUDCA antibody and an ursodeoxycholic acid (UDCA)-peroxidase conjugate as tracer, detected by enhanced chemiluminescence employing a portable charge-coupled device (CCD)-based device. The test was validated in 24 healthy subjects before and after treatment with Loperamide, a drug that increases OITT. The developed CL-EIA was accurate and precise, with a LLOQ of 50 pmol L(-1). The measured OITT for healthy subjects (291 ± 50 min) was fairly well correlated with OITT values obtained by measuring TUDCA in serum (r=0.89). An increased OITT was observed in all the studied subjects after Loperamide treatment. The CL immunosensor can be employed directly in gastroenterology and paediatric units and it can thus represent a new non-invasive simple test for OITT evaluation in a point-of-care setting, with improved diagnostic utility.
authors.affiliation: Department of Medical and Surgical Sciences, University of Bologna, Via Massarenti 9, 40138 Bologna, Italy.
authors.forename: Patrizia
authors.initials: P
authors.lastname: Simoni
authors.forename: Maria
authors.initials: M
authors.lastname: Magliulo
authors.forename: Mara
authors.initials: M
authors.lastname: Mirasoli
authors.forename: Amanda
authors.initials: A
authors.lastname: Vestito
authors.forename: Davide
authors.initials: D
authors.lastname: Festi
authors.forename: Giulia
authors.initials: G
authors.lastname: Roda
authors.forename: Antonio
authors.initials: A
authors.lastname: Colecchia
authors.forename: Aldo
authors.initials: A
authors.lastname: Roda
mesh_terms: D000284:Administration, Oral; D000328:Adult; D000930:Antidiarrheals / Q000494:pharmacology; D005260:Female; D005772:Gastrointestinal Transit; D006801:Humans; D007082:Ileum / Q000378:metabolism; D007124:Immunoenzyme Techniques; D007408:Intestinal Absorption; D008139:Loperamide / Q000494:pharmacology; D008163:Luminescent Measurements; D008297:Male; D008875:Middle Aged; D019095:Point-of-Care Systems; D013655:Taurochenodeoxycholic Acid / Q000008:administration & dosage / Q000493:pharmacokinetics*; D013997:Time Factors; D055815:Young Adult
chemical_list: D000930:Antidiarrheals; D013655:Taurochenodeoxycholic Acid; C031655:ursodoxicoltaurine; D008139:Loperamide