Radioactive multiplexing analytical methods for biomarkers discovery

A method of analysis comprising the steps of:

• (a) labeling molecules in a first sample with a first radioactive isotope;
• (b) labeling molecules in a second sample with a second radioactive isotope that is different from said first radioactive isotope;
• (c) mixing said first sample and said second sample into a mixture;
• (d) separating said mixture into a plurality of groups of molecules;
• and,
• (e) selectively quantifying each isotope from each group of molecules wherein a screen is used to selectively block a higher proportion of radiation from one isotope.

A method of isolating a difference between two samples comprising the steps of:

• (a) labeling molecules in a first sample with a first radioactive isotope;
• (b) labeling molecules in a second sample with a second radioactive isotope that is different from said first radioactive isotope;
• (c) mixing said first sample and said second sample into a mixture;
• (d) separating said mixture into a plurality of fractions;
• (e) quantifying a ratio of radioactive isotopes for each fraction;
• and,
• (f) comparing the ratios of radioactive isotopes among all fractions whereby at least one fraction with deviated ratio of radioactive isotopes is identified as a result said difference is isolated.

A method for finding a difference between two protein samples comprising the steps of:

• (a) labeling protein molecules in each sample with a unique radioactive isotope whereby one isotope is used per sample;
• (b) mixing the labeled protein molecules from said two samples together into a mixture;
• (c) contacting said mixture with an array;
• (d) measuring a ratio of radioactive isotopes at each spot on said array;
• and,
• (e) comparing the ratios of radioactive isotopes among a plurality of spots on said array whereby a spot with deviated ratio of radioactive isotopes can be identified.