Articles and methods involving detection of binding
View Patent ↗Articles and methods involving detection of binding between two or more species using MALDI are generally provided. In some embodiments, a method comprises exposing a first species to a composition comprising a second species, capturing the first species on a self-assembled monolayer, and performing MALDI on the self-assembled monolayer to generate a signal from the second species and a signal from a standard species present in the self-assembled monolayer. A ratio (first ratio) of the signal from the second species to the signal from the standard species may be compared to a cutoff value in order to determine if binding has occurred. This method may allow determination of a relative affinity of the second species for the first species.
1. A method for detecting binding between a first species and a second species, comprising:
exposing the first species to a composition comprising the second species;
capturing the first species on a self-assembled monolayer, wherein the self-assembled monolayer comprises a standard species prior to the capture of the first species thereon;
performing MALDI on the self-assembled monolayer to generate a signal from the second species and a signal from the standard species;
measuring the signal from the second species;
measuring the signal from the standard species; and
determining whether binding has occurred if a ratio of the signal from the second species to the signal from the standard species is greater than or equal to a cutoff value.
2. A method as in of claim 1 , wherein the first species is at least one of a polypeptide, a protein, an oligonucleotide, a DNA molecule, and an RNA molecule.
3. A method as in claim 1 , wherein the second species is at least one of a polypeptide, a protein, an oligonucleotide, a DNA molecule, an RNA molecule, and a molecule having a molecular weight of not more than 1,000 g/mol.
4. A method as in claim 1 , wherein the composition comprises a third species.
5. A method as in claim 4 , wherein the third species is at least one of a polypeptide, a protein, an oligonucleotide, a DNA molecule, an RNA molecule, and a molecule having a molecular weight of not more than 1,000 g/mol.
6. A method as in claim 4 , wherein a ratio of the wt % of the second species in the composition to the third species in the composition is greater than or equal to 0.5 and less than or equal to 2.
7. A method as in claim 1 , wherein the composition comprises a surfactant.
8. A method as in claim 1 , wherein the composition comprises an agent that reduces non-specific binding.
9. A method as in claim 1 , further comprising applying a matrix to the self-assembled monolayer.
10. A method as in claim 9 , wherein the matrix does not undergo fragmentation during MALDI-TOF.
11. A method as in claim 1 , wherein the self-assembled monolayer comprises at least one of streptavidin, neutravidin, a maleimide group, biotin, an alkyne group, an alkene group, an azide group, n-hydroxysuccinimide, dibenzocyclooctyl, nitriloacetic acid, glutathione, a phosphonate, benzylguanine, benzylcytosine, and a chloroalkane.
12. A method as in claim 1 , wherein the standard species is present at a known concentration within the monolayer.
13. A method as in claim 1 , wherein the standard species does not undergo fragmentation during MALDI-TOF.
14. A method as in claim 1 , wherein the standard species comprises an (EG) n -alkane thiol or an (EG) n -alkyl disulfide, wherein EG is ethylene glycol.
15. A method as in claim 1 , wherein the binding comprises non-covalent binding.
16. A method as in claim 1 , further comprising measuring a signal from a molecule having a molecular weight of not more than 1,000 g/mol, further comprising normalizing the signal from the molecule having the molecular weight of not more than 1,000 g/mol by the signal from the standard species, and further comprising determining the amount of binding that has occurred based on an area under a curve of a normalized signal from the molecule having the molecular weight of not more than 1,000 g/mol or based on a peak intensity of the normalized signal from the molecule having the molecular weight of not more than 1,000 g/mol.
17. A method as in claim 1 , wherein the composition comprises a control species.
18. A method as in claim 17 , further comprising measuring a signal from a control species, and further comprising determining that an abnormality has occurred if the signal from the control species is outside of a pre-determined range.
19. A method as in claim 1 , further comprising washing the self-assembled monolayer after capturing the first species.
20. A method for detecting binding between a first species and a second species, comprising:
exposing the first species to a composition comprising the second species;
capturing the first species on a self-assembled monolayer, wherein the self-assembled monolayer comprises a standard species, and wherein the standard species comprises a group capable of bonding and/or interacting with a support on which the self-assembled monolayer is disposed and/or that is bonded to and/or interacting with the support on which the self-assembled monolayer is disposed;
performing MALDI on the self-assembled monolayer to generate a signal from the second species and a signal from the standard species;
measuring the signal from the second species;
measuring the signal from the standard species; and
determining whether binding has occurred if a ratio of the signal from the second species to the signal from the standard species is greater than or equal to a cutoff value.