Particle Suspension
Particle Suspension - Related Videos
10:17
The Tail Suspension Test
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Cited by 534 •
2012
The tail-suspension test is validated as an experimental procedure to assess antidepressant efficacy of drug treatments in mice. Mice are suspended by their tails for six minutes and escape-related behaviors are assessed. We describe procedures used in conducting the tail suspension test.
02:41
Concentration and Purification of Viral Particles
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2026
Source: Fricano-Kugler, C. J., et al. Designing, Packaging, and Delivery of High Titer CRISPR Retro and Lentiviruses via Stereotaxic Injection. J. Vis. Exp. (2016).This video demonstrates the step-by-step process for concentrating and purifying lentiviral particles from a mixed suspension containing host cell debris. The procedure utilizes centrifugation, filtration, and PEG-salt precipitation to isolate viral particles while removing soluble impurities. The final product is resuspended in a...
03:37
Subatomic Particles
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2020
Dalton was only partially correct about the particles that make up matter. All matter is composed of atoms, and atoms are composed of three smaller subatomic particles: protons, neutrons, and electrons. These three particles account for the mass and the charge of an atom. The Discovery of the Electron The first clue about the subatomic structure came at the end of the 19th century when J.J. Thomson discovered the electron using a cathode ray tube. This apparatus consisted of a sealed glass...
04:16
ECM Suspension Preparation: A Technique to Obtain Homogenous Suspension from Tissue-derived Extracellular Matrix
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2023
This video describes the preparation of a homogenized and digested extracellular matrix suspension from decellularized and lyophilized tissues. This technique helps in fabricating ECM-derived porous foams and microcarriers for use as substrates in advanced 3D cell culture models.
03:39
Preparation of Virus-Enriched Suspension Using Stepwise Sucrose Centrifugation
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2026
Source: Vijayraghavan, S. and Kantor, B. A Protocol for the Production of Integrase-deficient Lentiviral Vectors for CRISPR/Cas9-mediated Gene Knockout in Dividing Cells. J. Vis. Exp., (2017)This video demonstrates a two-step ultracentrifugation method using sucrose gradients and cushions to purify and concentrate viral particles from cell culture supernatant. The procedure enables separation based on buoyant density, allowing recovery of intact virus suitable for downstream applications.
FAQs
Stability reflects a balance among particle size, density, liquid viscosity, Brownian motion, and surface interactions. Smaller particles may experience stronger random Brownian motion, while differences in density can promote settling. Viscosity affects movement through the liquid, and repulsive surface forces can reduce aggregation. These variables together determine how uniformly particles remain distributed during handling and analysis.
Particle size and Brownian motion affect how readily dispersed material changes position within the liquid. Particle density differences encourage settling, whereas Brownian motion supports continued random movement. The resulting balance influences whether a sample remains sufficiently uniform for collection or analysis. Controlling this behavior matters because nonuniform distribution can alter the composition of material taken from different parts of a suspension.
Electrostatic and steric interactions can create repulsive forces between nearby particles. Electrostatic repulsion arises from surface-associated charge effects, while steric repulsion limits close contact through surface structures or layers. By reducing particle aggregation, these interactions help preserve dispersion and support more consistent sampling, transport, or separation. Their effectiveness depends on the surface properties of the suspended material and surrounding liquid.
In genetic workflows, a uniform dispersion helps distribute cells, beads, or nucleic-acid-associated materials more evenly among samples. This can improve sampling consistency and make reactions or separations more comparable. The benefit is especially important when only a portion of the suspension enters an assay, because uneven distribution could cause different samples to receive different amounts of relevant material.
Genetics-related workflows may use suspensions containing cells, beads, or materials associated with nucleic acids. Keeping these components dispersed supports their movement through laboratory processes and helps maintain comparable sample composition. The appropriate behavior depends on the material's physical properties and surface interactions, making suspension characteristics relevant to molecular delivery, genetic analysis, and biotechnology applications.
Before sampling or separation, researchers should consider whether particles have settled or aggregated and whether the suspension remains sufficiently uniform. Particle size, density, viscosity, Brownian motion, and surface repulsion all influence that condition. Assessing these factors helps connect the physical state of the suspension with assay reliability, reaction consistency, and the representativeness of the material transferred for analysis.