6: Color Tests, Spectrophotometry, Immunoassays Flashcards
Trinder’s Reagent for Salicylate
Tridner’s reagent: mercuric chloride, water, 1 M HCl, ferric nitrate
Purple = salicylate
FPN Test for Phenothiazines
Ferric Chloride, Perchloric Acid, Nitric Acid
Color results depend on specific phenothiazine (pink red, orange, violet, blue)
20 % NaOH + pyridine + heat
Red in pyridine layer = trichloro +
Used for chloral hydrate, chloroform
Conway Diffusion for Ethanol
Outer ring = sample
Inner ring = potassium chromate
Green = ethanol (or other reducing agent)
Paraquat/ Diquat
0.1% sodium dithionite in 1 M NaOH
Blue = paraquat
Green = diquat
Reinsch test for Heavy Metals
Copper wire + acidified and heated sample matrix result in black or silvery deposits/staining
Dull black = arsenic
purple black = antimony
shiny black = bismuth
silver =mercury
Marsh Test for Arsenic
Covert arsenic into arsine gas and deposit it into a black film
Black = arsenic
technique that incorporates the binding reaction of a target substance (antigen) w/ an antibody
Immunoassay
In immunoassays, the drug of interest
Antigen
In immunoassays, the part of the antigen that is recognized by the immune system
Epitope
In immunoassays, part of antibody that binds with antigen
Paratope
In immunoassays, antibodies are the same as
immunoglobulions (Ig)
These are produced by live animals in antiserum.
Polyclonal antibodies
the concentration of an antibody as determined by finding the highest dilution at which it is still able to cause agglutination of the antigen
Titer
What is produced when an animal is given antigen (hooked with protein); ex vivo
Monoclonal antibodies
Type on immunoassay that allows measurement of labeled antigen w/o separating bound and free antigen
Homogeneous
When two substances (antigen and labeled antigen) compete for the same antibody binding sites
Competitive Binding
Type on immunoassay that requires separation of bound and free antigen before labeled antigen is measured
heterogeneous
*more common; think ELISA
Homogenous Immunoassay technique
-When labeled drug is bound to antibody, enzyme is inactive
-When enzyme is active (unbound bc specimen had antigens that bound) NAD is converted to NADH (measured at 340 nm)
Enzyme Multiplied Immunoassay Technique (EMIT)
Homogenous Immunoassay technique
When Fluorescein-linked drug is bound to antibody, the fluorescein label does not rotate freely and the absorbed polarized light is emitted; when the label is free, it rotates in solution and the amount of emitted light is reduced
Fluorescence Polarization Immunoassay (FPIA)
*Think Fluorescein, polarized light = FP