title: A liquid crystal-based sensor for real-time and label-free identification of phospholipase-like toxins and their inhibitors.
abstract: We report a liquid crystal (LC)-based sensor for real-time and label-free identification of phospholipase-like toxins. Beta-bungarotoxin exhibits Ca(2+)-dependent phospholipase A(2) activity whereas alpha-bungarotoxin and myotoxin II do not exhibit any phospholipase activity. The sensor can selectively identify beta-bungarotoxin, when it hydrolyzes a phospholipid monolayer self-assembled at aqueous-LC interface, through orientational responses of LCs. As a result, optical signals that reflect the spatial and temporal distribution of phospholipids during the hydrolysis can therefore be generated in a real-time manner. The sensor is very sensitive and requires less than 5pg of beta-bungarotoxin for the detection. When phospholipase A(2) inhibitors are introduced together with beta-bungarotoxin, no orientational response of LCs can be observed. In addition, the regeneration of the sensor can be done without affecting the sensing performance. This work demonstrates a simple and cost-effective LC-based sensor for identifying phospholipase-like toxins and for screening compound libraries to find potential toxin inhibitors.
authors.affiliation: Department of Chemical and Biomolecular Engineering, National University of Singapore, 10 Kent Ridge Crescent, Singapore 119260, Singapore.
authors.forename: Deny
authors.initials: D
authors.lastname: Hartono
authors.forename: Siok Lian
authors.initials: SL
authors.lastname: Lai
authors.forename: Kun-Lin
authors.initials: KL
authors.lastname: Yang
authors.forename: Lin-Yue Lanry
authors.initials: LY
authors.lastname: Yung
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation*; D002038:Bungarotoxins / Q000032:analysis* / Q000037:antagonists & inhibitors / Q000737:chemistry; D003199:Computer Systems; D004867:Equipment Design; D019544:Equipment Failure Analysis; D050866:Liquid Crystals / Q000737:chemistry*; D010740:Phospholipases / Q000032:analysis* / Q000737:chemistry; D010743:Phospholipids / Q000737:chemistry*; D012031:Refractometry / Q000295:instrumentation*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D002038:Bungarotoxins; D010743:Phospholipids; D010740:Phospholipases