title: Hybridization of bioelectrochemically functional infinite coordination polymer nanoparticles with carbon nanotubes for highly sensitive and selective in vivo electrochemical monitoring.
abstract: This study demonstrates the formation of a three-dimensional conducting framework through hybridization of bioelectrochemically active infinite coordination polymer (ICP) nanoparticles with single-walled carbon nanotubes (SWNTs) for highly sensitive and selective in vivo electrochemical monitoring with combination with in vivo microdialysis. The bioelectrochemically active ICP nanoparticles are synthesized through the self-assembly process of NAD(+) and Tb(3+), in which all biosensing elements including an electrocatalyst (i.e., methylene green, MG), cofactor (i.e., β-nicotinamide adenine dinucleotide, NAD(+)), and enzyme (i.e., glucose dehydrogenase, GDH) are adaptively encapsulated. The ICP/SWNT-based biosensors are simply prepared by drop-coating the as-formed ICP/SWNT nanocomposite onto a glassy carbon substrate. Electrochemical studies demonstrate that the simply prepared ICP/SWNT-based biosensors exhibit excellent biosensing properties with a higher sensitivity and stability than the ICP-based biosensors prepared only with ICP nanoparticles (i.e., without hybridization of SWNTs). By using a GDH-based electrochemical biosensor as an example, we demonstrate a technically simple yet effective online electroanalytical platform for continuously monitoring glucose in the brain of guinea pigs with the ICP/SWNT-based biosensor as an online detector in a continuous-flow system combined with in vivo microdialysis. Under the experimental conditions employed here, the dynamic linear range for glucose with the ICP/SWNT-biosensor is from 50 to 1000 μM. Moreover, in vivo selectivity investigations with the biosensors prepared by the GDH-free ICPs reveal that ICP/SWNT-based biosensors are very selective for the measurement of glucose in the cerebral system. The basal level of glucose in the microdialysates from the striatum of guinea pigs is determined to be 0.31 ± 0.03 mM (n = 3). The study offers a simple route to the preparation of electrochemical biosensors, which is envisaged to be particularly useful for probing the chemical events involved in some physiological and pathological processes.
authors.affiliation: Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, PR China.
authors.forename: Xulin
authors.initials: X
authors.lastname: Lu
authors.forename: Hanjun
authors.initials: H
authors.lastname: Cheng
authors.forename: Pengcheng
authors.initials: P
authors.lastname: Huang
authors.forename: Lifen
authors.initials: L
authors.lastname: Yang
authors.forename: Ping
authors.initials: P
authors.lastname: Yu
authors.forename: Lanqun
authors.initials: L
authors.lastname: Mao
mesh_terms: D000818:Animals; D015374:Biosensing Techniques / Q000379:methods*; D003342:Corpus Striatum / Q000737:chemistry*; D055664:Electrochemical Techniques / Q000379:methods*; D005947:Glucose / Q000032:analysis*; D042843:Glucose 1-Dehydrogenase / Q000737:chemistry; D006168:Guinea Pigs; D008297:Male; D008751:Methylene Blue / Q000031:analogs & derivatives / Q000737:chemistry; D017551:Microdialysis; D008839:Microelectrodes; D009243:NAD / Q000737:chemistry; D053758:Nanoparticles / Q000737:chemistry*; D037742:Nanotubes, Carbon / Q000737:chemistry*; D058105:Polymerization; D012680:Sensitivity and Specificity; D013725:Terbium / Q000737:chemistry
chemical_list: D037742:Nanotubes, Carbon; D013725:Terbium; D009243:NAD; D042843:Glucose 1-Dehydrogenase; C028673:methylene green; D005947:Glucose; D008751:Methylene Blue