title: Application of polymer quantum dot-enzyme hybrids in the biosensor development and test paper fabrication.
abstract: Both glutathione capped CdTe quantum dots (QDs) and enzymes were encapsulated with poly(diallyldimethylammonium chloride) (PDDA) via electrostatic attraction to form hybrid films. The obtained PDDA QD-enzyme hybrids feature both high fluorescence and biorecognition. In the obtained hybrid materials, the fluorescence emission of the QDs was stable for at least 3 months, and the structure and activity of the enzyme was also well maintained as the Michaelis constant of tyrosinase was determined to be 0.90 mmol/L, which is just 2 times higher than that of free enzyme. This hybrid material was then utilized as a platform for the development of biosensors based on the quenching effects of the enzymatic products on the emission of the QDs with a kind of phenol (catechol) and glucose as example analytes. The detection limits of catechol and glucose were 1.0 × 10(-5) and 5.0 × 10(-6) mol/L, respectively. Moreover, this hybrid material was applied to the fabrication of test paper for these two analytes. The test paper was very stable with respect to the fluorescence of the QDs and the activity of the enzyme maintained for at least 1 month.
authors.affiliation: Physikalische Chemie, TU Dresden, Bergstrasse 66b, 01062 Dresden Germany.
authors.forename: Jipei
authors.initials: J
authors.lastname: Yuan
authors.forename: Nikolai
authors.initials: N
authors.lastname: Gaponik
authors.forename: Alexander
authors.initials: A
authors.lastname: Eychmüller
mesh_terms: D000498:Allyl Compounds / Q000737:chemistry; D015374:Biosensing Techniques; D002104:Cadmium / Q000737:chemistry; D002396:Catechols / Q000032:analysis; D005947:Glucose / Q000032:analysis; D005949:Glucose Oxidase / Q000737:chemistry*; D005978:Glutathione / Q000032:analysis; D057230:Limit of Detection; D014442:Monophenol Monooxygenase / Q000737:chemistry*; D010209:Paper; D011108:Polymers / Q000737:chemistry; D045663:Quantum Dots; D000644:Quaternary Ammonium Compounds / Q000737:chemistry; D011934:Reagent Strips; D013050:Spectrometry, Fluorescence; D055672:Static Electricity; D013691:Tellurium / Q000737:chemistry
chemical_list: D000498:Allyl Compounds; D002396:Catechols; D011108:Polymers; D000644:Quaternary Ammonium Compounds; D011934:Reagent Strips; D002104:Cadmium; C508190:diallyldimethylammonium chloride; D005949:Glucose Oxidase; D014442:Monophenol Monooxygenase; D005978:Glutathione; D005947:Glucose; C034221:catechol; D013691:Tellurium