Patent ID: 7680609

Claim:
A biopolymer automatic identifying method, comprising: (a) obtaining a plurality of observed mass values, by subjecting a sample comprised of one or more biopolymers to MS/MS, producing candidate molecules; (b) matching at least one of said observed mass values with a theoretical mass value, in a predetermined database of known mass values using a suitably programmed computing device, for candidate molecules, wherein one of said candidate molecules has a high similarity score such that it is thereby identified as an internal reference; then (c) selecting at least one candidate molecule from (b) that has such a high similarity score using a suitably programmed computing device; (d) calibrating said plurality of observed mass values with said internal reference to produce calibrated mass values using a suitably programmed computing device, wherein said internal reference is the theoretical mass of the selected candidate molecule or molecules in (c), and wherein each of said calibrated mass values is determined by the equation Xc=X /(1+( aX+b )), wherein Xc is a calibrated mass value, X is an observed mass value, b =Σ{( M−mM )×( E−mE )}/Σ{( M−mM )2}, a=mE−bXmM, E =( X−M )/ M, mE =Σ( E )/ n , and mM =Σ( M )/ n , wherein M is the theoretical mass value for said candidate molecule and n is the total number of candidate molecules; (e) calculating relative error between said calibrated mass value of a candidate molecule in (d) and a theoretical mass value to determine the standard deviation of said relative error using a suitably programmed computing device; (f) determining a tolerance of the matching step using said standard deviation (e) and a suitably programmed computing device, wherein said tolerance is determined by the equation T c −K×S EC , wherein K is 1.5 to 3.0; optionally, (g) repeating steps (b)-(f) using a suitably programmed computing device; and then (h) comparing said calibrated mass values to said predetermined database, thereby to determine the identity of at least one of said biopolymers using a suitably programmed computing device.