METHOD FOR DETERMINATION OF A DEGREE OF IMMOBILIZATION OF OLIGONUCLEOTIDES ON THE SURFACE OF GOLD NANOPARTICLES

摘要

A method for determination of a degree of immobilization of oligonucleotides on the surface of gold nanoparticles is disclosed. The method comprises procedures of immobilization of oligonucleotides containing covalently bonded fluorescent marks on the surface of gold nanoparticles; centrifuging the mixture of gold nanoparticles and oligonucleotides for 20 minutes at 13400 rpm; measuring fluorescence levels for the starting solution of oligonucleotides, the resulted supernate and the standard solutions of oligonucleotides with various contents; plotting a calibration curve; using the calibration curve and the readings of the spectrofluometer for determination of the amount of oligonucleotides immobilized on the surface of gold nanoparticles at that the said amount is defined as a difference between the contents of oligonucleotides in the starting solution and the resulted supernate; determination of an average amount of oligonucleotides immobilized on the surface of a single particle by means of dividing the measured molar content of the immobilized oligonucleotides by the polar content of gold nanoparticles; determination of a surface density of immobilized oligonucleotides by means of dividing the average amount of oligonucleotides immobilized on the surface of a single particle by the average surface area of a nanoparticle.