Report CopyRight/DMCA Form For : Nanotechnology Modified Spr Biosensors General Aspects
A biosensor is a self contained integrated device which is capable of providing. specific quantitative or semi quantitative analytical information using a. biological recognition element biochemical receptor which is retained in. direct spatial contact with an physico chemical transduction element . IUPAC 1996 , Enzymes Electrochemical, Microorganisms Optical SIGNAL. Plant or animal tissues, Thermal Acquisition, Antibodies. Nucleic Acids Piezoelectrical, SAMPLE BIORECEPTOR TRANSDUCER ELABORATION. concentration determination,kinetic constants dissociation and association. affinity constants, finding an interaction molecule. thermodynamics, Quick and rich data acquisition, Non labeling. Real time monitoring, High surface sensitivity, Water environment. Advantages, Sensitive pM concentrations , Can re use chip surface up to 100 times. Low amounts of analyte ligand required, Immobilization effect. Difficulty in the measurements of low molecular, weight substances. Steric hindrance, Non specific binding to surface Drawbacks. Mass transport limitation, Careful design of control experiment and data analysis. Enhanced, affinity based, SPR biosensor, Overcome their. limitation to, detect small, Minimize non changes in. specific refractive index, adsorption caused from low. phenomena on molecular, the modified weight or low. Immobilization of surfaces which concentration,an high density can reduce the compounds at. and uniform sensitivity during the sensing,distribution of detection steps surface. antibodies onto,the sensor chip ,retaining their,specific antigen. binding activities The steric hindrance is another important issue to be. and maintaining focused the sensitivity decreases when the probe size is. accessibility to smaller than the target molecule size. the antigens, Poly amidoamine G4 PAMAM 6 3 2 pyridyl . dendrimers were employed as dithio propionamido hexanoate. nanotemplates for the,development of inorganic organic. hybrid colloids in aqueous, Tris 2 carboxyethyl phosphine TCEP . Mixed SAMs sensor chip modification , a 2 2 2 11 Mercaptoundecyl oxy ethoxy ethoxy ethyl alcohol . HS CH2 11 OCH2CH2 3OH , a 2 2 2 2 2 2 2 11 Mercaptoundecyl . oxy ethoxy ethoxy ethoxy ethoxy ethoxy ethoxy acetic acid . HS CH2 11 OCH2CH2 6OCH2CO2H , N 3 dimethyl aminopropyl N ethyl carbodiimide hydrochloride EDC . N hydroxysuccinimide NHS , N maleimidocaproic acid hydrazide EMCH . 1 hydroxybenzotriazole hydrate HOBT , SPR sensorgrams for the non specific adsorption of a mixture of proteins to different modified surfaces . ethanolamine derivatized SAM a underivatized SAM b AuNP G4 OH SAM c and AuNP G4 NH2 SAM. d modified surface The mixture of proteins used in this experiment contained bovine serum albumin . lysozyme trypsin ribonuclease A aldolase fibrinogen ovalbumin and superoxide dismutase each at a. concentration of 1 0 mg ml 1 in PBS , SPR angle time curves for the. detection of the affinity,interaction between Ins Ab 2 5. nM and insulin immobilized on,AuNP G4 OH SAM modified. gold surface ,Subsequent injection of , 0 1 M PBS pH 7 2 a . coupling buffer , Ins Ab b , 0 1 M PBS pH 7 2 c , dissociation buffer . 10 mM glycine HCl pH 3 0, with NaCl 0 1 M d , regeneration buffer . 0 1 M PBS pH 7 2 e , SPR sensorgrams obtained after blank. subtraction for the detection of the,affinity interaction between insulin . immobilized on AuNP G4 OH and,variable concentration of Ins Ab nM . 0 2 a 0 4 b 0 8 c 1 6 d 2 5 e ,4 2 f 6 2 g 8 4 h 12 5 i and. Calibration curves corresponding to,the SPR angle shift at different. concentrations of added Ins Ab on the,insulin immobilized onto AuNP G4 OH. close symbols and G4 OH open,symbols SAM modified surface .