Method and device of using aqueous two-phase systems (ATPS) for enhancing diagnostics for sexually transmitted infections

A method of detecting a pathogen associated with a sexually transmitted disease or infection in a subject, said method comprising:

• (f) obtaining a specimen comprising said pathogen from said subject;
• (g) removing interfering molecules that interfere with detection of said pathogen by reacting said interfering molecules with a purifying agent, thereby obtaining a sample solution substantially free from said interfering molecules;
• (h) concentrating said pathogen in said sample solution by a concentrating module, said concentrating module comprises a porous material precoated with components of an Aqueous Two-Phase System (ATPS), wherein when said sample solution flows through said porous material, two separated phases are formed, wherein the pathogen is concentrated in one of the two separated phases, thereby obtaining a concentrated solution;
• (i) allowing said concentrated solution to migrate to a conjugate pad comprising labeled biorecognition molecules, each of which comprising a label and a biorecognition molecule, wherein said pathogen is bound by said biorecognition molecules, thereby obtaining a complex between said labeled biorecognition molecules and said pathogen, and
• (j) detecting said complex on a testing module comprising a membrane covered with a control line and one or more test lines,
• wherein positive results at said control line and one or more test lines indicate the presence of said pathogen in said subject, wherein said purifying agent forms a precipitate by reacting with said interfering molecules, and wherein said purifying agent is selected from the group consisting of citric acid, lactic acid, acetic acid, and activated carbon.