The invention, provides a method, apparatus and system for separating blood and other types of cellular components, and can be combined with holographic optical trapping manipulation or other forms of optical tweezing. One of the exemplary methods includes providing a first flow having a plurality of blood components; providing a second flow; contacting the first flow with the second flow to provide a first separation region; and differentially sedimenting a first blood cellular component of the plurality of blood components into the second flow while concurrently maintaining a second blood cellular component of the plurality of blood components in the first flow. The second flow having the first blood cellular component is then differentially removed from the first flow having the second blood cellular component. Holographic optical traps may also be utilized in conjunction with the various flows to move selected components from one flow to another, as part of or in addition to a separation stage.

The present invention provides methods for analyzing a target compound from a biological sample. In one aspect, a method for analyzing a target compound in a biological sample can comprise delivering a biological sample through an affinity column, the affinity column having a binding ligand coupled to a stationary structural support, wherein the affinity column has a high density of the binding ligand per the stationary structural support and wherein the binding ligand has been preselected to cause weak affinity separation zonal retardation of the target compound from the biological sample forming a target compound fraction and a biological sample fraction and detecting the target compound by mass spectrometry.

The disclosure discloses a biomarker in osteoporosis intervention therapy by bone peptide, the biomarker including a lipid and lipid-like molecule, an organic acid and its derivative, and/or a neurotransmitter, wherein the lipid and lipid-like molecule includes one or more of taurine, arachidonic acid, 1-palmitoyl-2-hydroxy-sn-glycerol-3-phosphoethanolamine, (4Z, 7Z,10Z,13Z,16Z,19Z)-4,7,10,13,16,19-docosahexaenoic acid, 1-stearoyl-2-hydroxy-sn-glycerol-3-phosphocholine, taurodeoxycholic acid, taurochenodeoxycholate or taurocholic acid. The disclosure discloses a screening method of a biomarker in the anti-osteoporosis activity of bone peptide. The disclosure discloses a use of the biomarker.

This disclosure relates to the use of size exclusion chromatography and/or size exclusion chromatography with multi-angle light scattering technology to characterize viral particles such as adeno-associated virus and lentivirus particles. The disclosed methods are also useful for estimating the titer of viral particles, determining the integrity of the viral particles and estimating the amount of DNA encapsidated in the viral particle.

A method and system are disclosed for isolating intact acellular particles using size exclusion and for obtaining size and concentration of such isolated particles. In one embodiment, the disclosure is directed to use of Particle Purification Liquid Chromatography (PPLC), a high-resolution chromatographic size-guided turbidimetry-enabled system for dye-free isolation, on-line characterization, and retrieval of intact acellular particles, including extracellular vesicles (EVs) and membraneless condensate particles (MCs) from various biofluids.

The present invention provides a reference fingerprint of virgin olive oil, and an establishment method and an application thereof. By using UPLC-FLD, the chromatographic information of various components in the extra virgin olive oil is obtained, breaking through the limitation of establishment of fingerprints by means of conventional GC-MS method and based on the fatty acid composition of edible oil, and further solving the problem that traditional fingerprints only use a single component for determination and thus result in false positivity. Meanwhile, similarity calculation is conducted on the chromatographic information of serial extra virgin olive oil, establishing a reference fingerprint of virgin olive oil, reinforcing the polymorphism of fingerprint information, reflecting its differences from edible oil from the perspectives of the substance composition, distribution, and content of virgin olive oil, helping improve accuracy of identification, and enabling rapid, convenient and accurate identification of the quality of virgin olive oil.

The subject technology is directed to a CO.sub.2-based chromatography system and method for rapid determination of the levels and/or the presence or absence of steroids or steroid derivatives in a sample.

The invention provides a method for verifying the age of an animal providing meat using volatile profiles that comprises the step of providing a sample of animal meat. The method uses one or more chemical analyses to obtain a profile of a set of volatile organic compounds from a sample of meat from an animal. The profile is fit to a mathematically discriminating function resulting. The data obtained is analyzed in order to establish a correlation between the age of the animal (tooth development) and volatiles exuded by meat.

Provided is a method for determining, in a sample, enrichments of a first and a second stable-labeled tracer of a target substance including glucose, the first tracer and the second tracer having the same or similar chemical structure as the target substance, the method including: ionizing the first tracer, the second tracer and the target substance of the sample; measuring intensities of ions deriving from the target substance, the first tracer and the second tracer using a mass analyzer; calculating an enrichment of the first tracer from a first ratio of intensity of the ions deriving from the first tracer to the intensity of the ions deriving from the target substance employing a first calibration curve independent of enrichments of each of the second tracer; wherein the mass analyzer is operated so as to resolve an ion peak deriving from a tracer and having a width Δ(m/z) at half maximum peak height equal to or smaller than 1×10.sup.−2.

Compositions and methods for determining the level of thiol and disulfide containing molecules in a sample are provided. The compositions and methods can be used to determine the level of oxidative stress in a subject with or without antioxidant treatment. Also provided are biomarkers of oxidative stress.