US 9,802,818 B2Granted

Sorting process of nanoparticles and applications of same

AssigneeNorthwestern University

InventorsTimothy P. Tyler, Anne-Isabelle Henry, Richard P. Van Duyne, Mark C. Hersam

Life of this patent

Estimating the term…

Loading patent…

Abstract

In one aspect of the present invention, a method for sorting nanoparticles includes preparing a high-viscosity density gradient medium filled in a container, dispersing nanoparticles into an aqueous solution to form a suspension of the nanoparticles, each nanoparticle having one or more cores and a shell encapsulating the one or more cores, layering the suspension of the nanoparticles on the top of the high-viscosity density gradient medium in the container, and centrifugating the layered suspension of the nanoparticles on the top of the high-viscosity density gradient medium in the container at a predetermined speed for a predetermined period of time to form a gradient of fractions of the nanoparticles along the container, where each fraction comprises nanoparticles in a respective one of aggregation states of the nanoparticles.

Claims17

Dependent claims

A method for sorting nanoparticles, comprising:

(a) preparing an aqueous iodixanol density gradient medium filled in at least one centrifugal tube, wherein the aqueous iodixanol density gradient medium is formed of about 30%-60% weight per volume iodixanol;
(b) dispersing nanoparticles into an aqueous solution to form a suspension of the nanoparticles, wherein each nanoparticle comprises one or more gold cores and a silica shell encapsulating the one or more gold cores, wherein the shell is formed such that the nanoparticles are dispersed in the aqueous solution without need for functionalization or surfactants;
(c) layering the suspension of the nanoparticles on the top of the aqueous iodixanol density gradient medium in the at least one centrifugal tube;
(d) centrifuging the layered suspension of the nanoparticles at a predetermined speed with a centrifugal force of about 500 g for a predetermined period of time about 10 minutes to form a gradient of fractions of the nanoparticles in the at least one centrifugal tube by sedimentation coefficients of the nanoparticles in a transient centrifugal regime so as to sort the nanoparticles according to their sedimentation coefficients,
wherein the sedimentation coefficient of a fraction of the nanoparticles satisfies with the relationship of:
s
=
m
⁡
(
1
-
ρ
s
/
ρ
p
)
f
,
where m is a total nanoparticle mass of the fraction, ρs and ρp are respectively densities of the aqueous iodixanol density gradient medium and the fraction of the nanoparticles, and f is a frictional coefficient that depends on a shape of the fraction of the nanoparticles and a viscosity of the aqueous iodixanol density gradient medium;
wherein each fraction comprises nanoparticles in a respective one of aggregation states of the nanoparticles;
wherein each aggregation state is a monomer state or a cluster state that ranges from dimers to dodecamers;
and
wherein the nanoparticles are separated in the at least one centrifugal tube according to their sedimentation coefficients so that a fraction of the nanoparticles in the monomer state is in a top portion of the at least one centrifugal tube and fractions of the nanoparticles in the cluster state that ranges from dimers to dodecamers are subsequently underneath the fraction of the nanoparticles in the monomer state in the at least one centrifugal tube;
and
(e) collecting each fraction of the nanoparticles from the at least one centrifugal tube.

24 more elements

A method for sorting nanoparticles, comprising:

(a) preparing a high-viscosity density gradient medium filled in a container, wherein the aqueous iodixanol density gradient medium is formed of about 30%-60% weight per volume iodixanol;
(b) dispersing nanoparticles into an aqueous solution to form a suspension of the nanoparticles, wherein each nanoparticle comprises one or more cores and a shell encapsulating the one or more cores, wherein the shell is formed of a material such that the nanoparticles are dispersed in the aqueous solution without need for functionalization or surfactants;
(c) layering the suspension of the nanoparticles on the top of the high-viscosity density gradient medium in the container;
and
(d) centrifuging the layered suspension of the nanoparticles on the top of the high-viscosity density gradient medium in the container at a predetermined speed with a centrifugal force of about 500 g for a predetermined period of time about 10 minutes to form a gradient of fractions of the nanoparticles along the container by sedimentation coefficients of the nanoparticles in a transient centrifugal regime so as to sort the nanoparticles according to their sedimentation coefficients,
wherein the sedimentation coefficient of a fraction of the nanoparticles satisfies with the relationship of:
s
=
m
⁡
(
1
-
ρ
s
/
ρ
p
)
f
,
where m is a total nanoparticle mass of the fraction, ρs and ρp are respectively densities of the high-viscosity density gradient medium and the fraction of the nanoparticles, and f is a frictional coefficient that depends on a shape of the fraction of the nanoparticles and a viscosity of the high-viscosity density gradient medium;
wherein each fraction comprises nanoparticles in a respective one of aggregation states of the nanoparticles;
wherein each aggregation state is a monomer state or a cluster state that ranges from dimers to dodecamers;
and
wherein the nanoparticles are separated in the container according to their sedimentation coefficients so that a fraction of the nanoparticles in the monomer state is in a top portion of the container and fractions of the nanoparticles in the cluster state that ranges from dimers to dodecamers are subsequently underneath the fraction of the nanoparticles in the monomer state in the container.

23 more elements

Dependencies are inferred from the claim text.

Facts

Application: 13/461,521Filed 1 May 2012 · us provisional application
Priority: 3 May 2011
Published: US 2012/0281213 A18 Nov 2012
Granted: 31 Oct 2017
Term ends: Not estimatedThe source records don’t support an estimate.

Classification5 codes

G01N 21/658
Raman scattering: enhancement Raman, e.g. surface plasmons
B82Y 30/00
Nanotechnology for materials or surface science
B82Y 40/00
Manufacture or treatment of nanostructures
G01N
Investigating or analysing materials by determining their chemical or physical properties