Polystyrene Microspheres

We offer uniform polystyrene latex microspheres that may be used as-is for standards or markers, or coated with proteins via adsorption for use in diagnostic tests and assays. See TechNote 204, Adsorption to Microspheres. Our spheres are synthesized via emulsion polymerization, and are available in diameters from ~20nm-90µm, with typical size CVs of 5-10%. For applications that require highly stringent CVs (e.g. 2-5%), call for product availability. Most products are supplied as a 10% solids suspension (100mg/mL) in de-ionized water with surfactant and sodium azide.

PS AND PS/DVB

Many proteins may be easily and stably absorbed to hydrophobic, non-functionalized microspheres. Divinylbenzene (DVB) confers additional solvent and heat resistance to our crosslinked spheres. Unless noted otherwise, PS and PS/DVB microspheres are available as ~10% solids (w/w) aqueous suspensions in these standard amounts: 0.5g, 1.0g, 1.5g, and 5.0g.

REFERENCES

• Joubert, M, Hokom, M, Eakin, C, Zhou, L, Deshpande, M, Baker,M, …Jawa, J (2012) Highly Aggregated Antibody Therapeutics Can Enhance the in Vitro Innate and Late-stage T-cell Immune Responses J Biol Chem 287:25266
• Noyhouzer, T., Perry, S. C., Vicente-Luis, A., Hayes, P. L., & Mauzeroll, J. (2018). The Best of Both Worlds: Combining Ultramicroelectrode and Flow Cell Technologies. Journal of The Electrochemical Society, 165(2), H10-H15. (Cat. PS03005, 0.9µm PS nanoparticles)
• Fernandez-Bravo A, Yao K, Barnard ES, Borys N, Levy E, Tian B, … Schuck JP. (2018) Continuous-wave upconverting nanoparticle microlasers.Nature Nanotech;06/18.1748-3395 (nanoparticle-coated 5µm PS beads)
• Arifin, N, Yunus, M H, Nolan, TJ, Lok, JB, & Noordin, R. (2018). Identification and Preliminary Evaluation of a Novel Recombinant Protein for Serodiagnosis of Strongyloidiasis. (PS02002, 0.5µm PS microspheres to pre-adsorb serum samples for immunoscreening)
• Choy C H, & Botelho RJ. (2017). Quantifying phagocytosis by immunofluorescence and microscopy. In Phagocytosis and Phagosomes (pp. 43-53). Humana Press, New York, NY.(PS05003, 3.87µm PS, IgG opsonized with fluorescent secondary Ab)
• Gigault C, Dalnoki-Veress K, & Dutcher JR. (2001) Changes in the morphology of self-assembled polystyrene microsphere monolayers produced by annealing. Journal of colloid and interface science, 243(1), 143-155.(1µm PS used to fabricate self-assembled monolayers)

Our carboxylate-modified polystyrene latex microspheres are suitable for the covalent immobilization of proteins, peptides, and nucleic acids. They are synthesized via emulsion polymerization, and are available in diameters up to ~20µm, with typical size CVs of 10%. Most products are supplied as 10% solids suspension (w/w) in de-ionized water with surfactant and sodium azide.

CARBOXYL POLYSTYRENE

EDAC-mediated coupling is often used for the covalent immobilization of amine-terminated proteins, DNA, or other molecules on carboxyl-functionalized PS and P(S/DVB) microspheres. Carboxyl polymer microspheres are available as ~10% solids (w/w) aqueous suspensions in these standard amounts: 0.5g, 1.0g, 1.5g, and 5.0g.

New to beads? See our PolyLink Protein Coupling Kit and TechNote 205, Covalent Coupling, for a protocol and tips on coating optimization and QC.

REFERENCES

• Park, MK, Briles, DE, Nahm, MH (2000) A Latex Bead-Based Flow Cytometric Immunoassay Capable of Simultaneous Typing of Multiple Pneumococcal Serotypes (Multibead Assay) Clin Vaccine Immunol v7(3) 486-489
• Blanchette C, Lacayo CI, Fischer NO, Hwang M, Thelen MP (2012) Enhanced Cellulose Degradation Using Cellulase-Nanosphere Complexes. PLoS ONE 7(8): e42116
• Rodrigues OR, & Monard S, (2016) A rapid method to verify single-cell deposition setup for cell sorters. Cytometry 89: 594–600
• Borque L, Bellod L, Rus A, Seco L, Galisteo-Gonzàles F (2000) Development and Validation of an Automated and Ultrasensitive Immunoturbidimetric Assay for C-Reactive Protein. Clin Chem 46(11) 1839-1842
• Perez-Amodio S, Holownia P, Davey C, Price C (2001) Effects of the Ionic Environment, Charge, and Particle Surface Chemistry for Enhancing a Latex Homogeneous Immunoassay of C-Reactive Protein. Anal. Chem.73 (14) 3417–3425
• Lucas L, Han J, Yoon J (2006) Using highly carboxylated microspheres to simplify immunoassays and enhance diffusional mixing in a microfluidic device. Colloids and Surf. B: Biointerfaces 49(2) 106-111
• Fu L, Kang C, Zhang P, Kang X, Li X, Wang H, …Qiu Y (2015) A modified quick PETIA for detecting anti-CCP antibodies in human serum, Anal Methods Issue 7
• Deegan O, Walshe K, Kavanagh K, Doyle S. (2003) Quantitative detection of C-reactive protein using phosphocholine-labelled enzyme or microspheres. Anal. Biochem. 312 p175–181 (turbidimetric assay, 0.21µm PS-COOH)
• Koskinen JM, Soukka JM, Meltola NJ, & Koskinen JO. (2018). Microbial identification from faces and urine in one step by two-photon excitation assay technique. Journal of immunological methods, 460, 113-118.(Cat. PC05003, 3.2µm PS-COOH microspheres, coated with anti-Legionella or anti-adenovirus Ab in ArcDia’s TPX assay.)
• Nanavaty N, Lin L, Hinckley SH, & Kuret J. (2017) Detection and quantification methods for fibrillar products of in vitro tau aggregation assays. In Tau Protein (pp. 101-111). Humana Press, New York, NY.(Anionic PS-COOH, 40-90nm as tau aggregation inducers)

AMINE POLYSTYRENE

Amine-functionalized microspheres offer further options for coupling of biomolecules. Glutaraldehyde is commonly used for the immobilization of amine-containing compounds, and specialized linkers are available for targeted coupling of thiol or carbohydrate moieties. See TechNote 205, Covalent Coupling. Unless otherwise noted amine polymer microspheres are available as ~10% solids (w/w) aqueous suspensions in these standard amounts: 0.5g, 1.0g, 1.5g, and 5.0g. For microspheres larger than 1.00µm, please call for availability.

REFERENCES

• Schleicher KD, Dettmer SL, Kapinos LE, Pagliara S, Keyser UF, Jeney S, LimRoderick YH (2014) Selective transport control on molecular velcro made from intrinsically disordered proteins. Nat Nano 9, 525-530
• Bandura DR, Baranov VI, Ornatsky OI, Antonov A, Kinach R, Lou X… Tanner S.(2009) Mass Cytometry: Technique for Real Time Single Cell Multitarget Immunoassay Based on Inductively Coupled Plasma Time-of-Flight Mass Spectrometry. Anal Chem 81,6813–6822

DYED POLYSTYRENE

Our non-functionalized microspheres are suitable for coating with antibody or other large proteins via adsorption. See TechNote 204, Adsorption to Microspheres, for a general adsorption protocol. Unless noted otherwise, these visibly dyed microspheres are supplied as a 5% solids suspension (w/v) and are available in these standard amounts: 0.5g, 1.0g, 1.5g, and 5.0g.

References

Henderson, K., & Stewart, J. (2002). Factors influencing the measurement of oestrone sulphate by dipstick particle capture immunoassay. Journal of immunological methods, 270(1), 77-84.(0.3, 0.5, and 0.8µm dyed blue PS)

Henderson, K., & Stewart, J. (2000). A dipstick immunoassay to rapidly measure serum oestrone sulfate concentrations in horses. Reproduction, Fertility and Development, 12(4), 183-189.(0.31µm dyed blue PS)

Campbell, K., Fodey, T., Flint, J., Danks, C., Danaher, M., O’Keeffe, M., … & Elliott, C. (2007). Development and validation of a lateral flow device for the detection of nicarbazin contamination in poultry feeds. Journal of agricultural and food chemistry, 55(6), 2497-2503.(0.43µm dyed blue PS)

DYED CARBOXYL POLYSTYRENE

Biomolecules may be covalently immobilized to carboxyl-functionalized microspheres. A general coupling protocol is provided within TechNote 205, Covalent Coupling. Our dyed carboxyl microspheres are impregnated with vibrant dyes for optimal visualization. See our color palette for a representation of our standard colors. Unless noted otherwise, they are supplied as a 5% solids suspension (w/v) and are available in four standard volumes: 0.5g, 1.0g, 1.5g, and 5.0g.

REFERENCES

Terao, Y, Takeshita, K, Nishiyama, Y, Morishita, N, Matsumoto, T, & Morimatsu, F. (2015) Promising Nucleic Acid Lateral Flow Assay Plus PCR for Shiga Toxin–Producing Escherichia coli. Journ of food protection, 78(8), 1560-1568.

Sheng, W, Li, S, Liu, Y, Wang, J, Zhang, Y, & Wang, S. (2017). Visual and rapid lateral flow immunochromatographic assay for enrofloxacin using dyed polymer microspheres and quantum dots. Microchimica Acta, 184(11), 4313-4321.(Dyed Black carboxyl microspheres)

DYED PROTEIN-COATED POLYSTYRENE

At times, our inventory includes streptavidin-coated dyed microspheres supplied as ~1% solids (w/v) aqueous suspensions.

REFERENCES

• Li S, Liu Y, Wang Y, Wang M, Liu C, & Wang Y. (2019) Rapid detection of Brucella spp. and elimination of carryover using multiple cross displacement amplification coupled with nanoparticles-based lateral flow biosensor. Frontiers in Cellular and Infection Microbiology, 9, 78. (Streptavidin Crimson Red nanoparticles [CP01R] for binding of biotinylated Brucella spp. amplicons in lateral flow biosensor.)

Fluorescent microspheres are a mainstay in diagnostics and life sciences research, finding use as fluorescent markers, assay substrates, and instrument standards. In order to meet the unique performance criteria required of microparticles in these different applications we stock an extensive inventory of fluorescent microspheres and offer custom dyeing services.

FLUORESCENT POLYSTYRENE

Our non-functionalized microspheres are suitable for coating via adsorption. See spectra for available fluorescent dyes. See TechNote 204, Adsorption to Microspheres, for a general adsorption protocol. Fluorescent polymer microspheres are available in these standard volumes: 1mL, 5mL, 10mL, and 100mL.

FLUORESCENT CARBOXYL POLYSTYRENE

Biomolecules may be covalently immobilized to carboxyl-functionalized microspheres. A general coupling protocol is provided in TechNote 205, Covalent Coupling. Fluorescent carboxyl microspheres and Europium chelate microspheres are available in these standard volumes: 1mL, 5mL, 10mL, and 100mL. See spectra for available fluorescent dyes. See also our Quantumplex™ kits for suspension array development.

EUROPIUM CHELATE

Our europium products offer extremely bright fluorescence and exceptional stability, in addition to well functionalized carboxylated surfaces for the covalent attachment of ligand. See PDS 741.pdf. See spectra for available fluorescent dyes.

FLUORESCENT MAGNETIC POLYMER

Both Encapsulated (ME catalog codes) and Classical (MC catalog codes) superparamagnetic microspheres are synthesized using a process that results in the distribution of iron oxide crystals throughout the polymer matrix. For specific information on the use of fluorescent magnetic particles for cell labeling & tracking, see TSD 0748. The surfaces of Encapsulated magnetic microspheres are expected to be free of iron oxide, while the Classical version will have some exposed iron oxide. COMPEL microspheres (UMC catalog codes) are highly uniform and spherical. Fluorescent magnetic microspheres are available in these standard volumes: 1mL, 5mL, 10mL, and 100mL. See spectra for available fluorescent dyes.

FLUORESCENT PROTEIN COATED POLYMER

Our inventory includes a variety of streptavidin coated fluorescent microspheres. Please select the catalog code link below or contact our Customer Service Department for specific availability. See spectra for available fluorescent dyes.

STARLIGHT™ CALIBRATION SLIDES

DRAGON GREEN INTENSITY STANDARD

The Dragon Green Intensity Standard is a kit consisting of five individual populations of ~8µm polystyrene-based microspheres dyed with increasing amounts of the Dragon Green fluorophore. Dragon Green is an excellent spectral surrogate for fluorescein, and is suitable for use with fluorescein filter sets. View excitation and emission spectra here.

FLASH RED INTENSITY STANDARD

The Flash Red Intensity Standard is a kit consisting of five individual populations of ~8µm polystyrene-based microspheres dyed with increasing amounts of the Flash Red fluorophore. As Flash Red is spectrally similar to Cy™5, traditional red fluorophore filter sets (e.g. Cy™5/microscope, PE-Cy™5 or APC/cytometer) may be used with this standard. View excitation and emission spectra here.

When circumstances call for the rapid development of microsphere reagents, particles coated with affinity binding proteins offer a ready solution. Affinity binding protocols are straightforward, typically involving a simple incubation of the spheres with the appropriate ligand. Binding proteins also provide an opportunity to optimally orient the ligand, as with the end-point immobilization of biotinylated oligonucleotides to streptavidin-coated microspheres, or the Fc-specific immobilization of antibodies via Protein A or G.

Particles coated with binding proteins also find significant use in purifications. Streptavidin-coated microspheres are often used in the isolation of biotinylated PCR amplicons. Protein A and Protein G microspheres are utilized for purification of antibodies and Fc-tagged fusion proteins, as well as for the recovery of Ab/Ag complexes in immunoprecipitation.

STREPTAVIDIN

Our streptavidin and SuperAvidin™ coated microspheres offer simple and extremely stable binding of biotinylated molecules, such as antibodies, peptides, and oligonucleotides for use in diagnostics, screening, and affinity purifications. See TechNote 101, ProActive^® Microspheres. Streptavidin coated microspheres are available as ~1% solids (w/v) aqueous suspensions in four standard volumes: 1mL, 2mL, 5mL, or 10mL.

STREPTAVIDIN POLYSTYRENE

STREPTAVIDIN MAGNETIC POLYMER

The surfaces of Encapsulated magnetic microspheres are expected to be free of iron oxide, while the Classical version will have some exposed iron oxide. COMPEL microspheres (UMC catalog codes) are highly uniform and spherical. Fluorescent magnetic microspheres are available as ~1% solids (w/v) aqueous suspensions in these standard volumes: 1mL, 5mL, 10mL, and 100mL. See spectra for available fluorescent dyes.

 STREPTAVIDIN FLUORESCENT POLYSTYRENE

STREPTAVIDIN DYED POLYSTYRENE

Streptavidin-coated dyed microspheres supplied as ~1% solids (w/v) aqueous suspensions.

BIOTIN

Our biotin-coated microspheres have been fully characterized in terms of their ability to bind free avidin, and therefore will require minimal optimization when determining the correct concentration of ligand to be bound. Biotin coated beads are supplied as ~1% solids (w/v) aqueous suspensions. See TechNote 101, ProActive^® Microspheres, for sample applications and procedures.

PROTEIN A AND PROTEIN G

Protein A and Protein G are proteins that readily bind the Fc regions of many types of antibodies. For this reason, they are used extensively for affinity purification of antibodies from serum or cell culture supernatant, and for capture of immunoprecipitated protein complexes. When Protein A and Protein G microspheres are used as reagents in tests and assays, the immobilized antibodies may be crosslinked to the Protein A- or Protein G-coated support for long-term stability. See TechNote 101, ProActive^® Microspheres. Protein A and Protein G coated microspheres are available as ~1% solids (w/v) aqueous suspensions in four standard volumes: 1mL, 2mL, 5mL, or 10mL.