National Institutes of Health, a Component of the US Dept. of Health & Human Services

Joshua Aden Welsh

Jay A Berzofsky

Jennifer C Jones

Ari Rosner

Aizea Morales-Kastresana

William G Telford

Katherine M McKinnon

Disclosed is a method of purifying extracellular vesicles in a sample comprising extracellular vesicles and molecules that are not bound to the extracellular vesicles. The method includes (a) providing a mixed mode resin composition containing a first resin having pores with a pore size that traps unbound molecules by at least by a size exclusion mechanism, and a second resin containing at least one affinity ligand; (b) contacting the sample with the mixed mode resin composition to trap at least a portion of the unbound molecules; and (c) separating the sample from the mixed mode resin composition and obtaining a sample containing extracellular vesicles at a higher concentration than prior to step (b). Further disclosed is a method of labeling an extracellular vesicle with a fluorophore that labels proteins which includes the use of a mixed mode resin composition.

Purification and labeling of extracellular vesicles using a mixed mode resin composition

A molecular nanotag is disclosed that includes a core nanoparticle with a diameter of less than about 100 nm, with an optional shell surrounding the core, and an armor bound to the surface of the core nanoparticle, or if present, to the surface of the shell. The molecular nanotag also includes a functionalized end with a fixed number of binding sites that can selectively bind to a molecular targeting ligand. Any one of, or any combination of, the core, the shell and the armor contribute to fluorescence, light scattering and/or ligand binding properties of the molecular tag that are detectable by microscopy or in a devices that measures intensity or power of fluorescence and light scattering. The light scattering intensity or power of the assembled structure is detectable above the specific level of the reference noise of a device detecting the light scattering intensity or power, its fluorescence intensity or power has sufficient brightness for detection above the limit of detection for the instrument, and ligand specificity is conferred by the ligand binding component. Methods of biomarker and biosignature detection using the molecular tags are also disclosed.

Molecular nanotags

Apparatus include an illumination source configured to produce and direct a multi-wavelength illumination beam to a microfluidic target that can include nanotags, a detector configured to receive a multi-wavelength detection beam from the microfluidic target and to produce a detection signal, wherein the multi-wavelength detection beam comprises light that is elastically side-scattered by an interaction between the multi-wavelength illumination beam and the nanotags in the microfluidic target, and a processor configured to receive the detection signal and to determine the presence of the nanotags in the microfluidic target by comparing multiple wavelength side-scatter intensity characteristics of the detection signal with predetermined multi-wavelength elastic side-scatter intensity profiles of one or more nanotag types. Methods are also disclosed that determine the presence of different nanotags responsive to a multi-wavelength detection beam based on a detected signal and predetermined multi-wavelength elastic side-scatter intensity profiles for different nanotag types.

Growing community of inventors

North Bethesda, MD, United States of America

Joshua Aden Welsh