{"product_id":"carboxylated-polystyrene-latex-beads-5-0-5-9-um","title":"Carboxylated Polystyrene Latex Beads (5.0–5.9 µm)","description":"\u003cdiv style=\"max-width:1400px; margin:0 auto; padding:40px 20px; font-family:'Open Sans',sans-serif; font-weight:300; background:#fff; color:#333; font-size:0.95rem; box-sizing:border-box;\"\u003e\n  \u003cdiv style=\"display:flex; flex-direction:column; gap:20px;\"\u003e\n\u003ch2 style=\"margin:0; font-weight:600;\"\u003eCarboxylated Polystyrene Latex Beads (5.0–5.9 µm) – Catalog #B2025494\u003c\/h2\u003e\n\u003cp\u003eCarboxylated polystyrene latex beads (Catalog #B2025494) are supplied as 5 mL of a uniform suspension of polymer spheres, 5.0 to 5.9 micrometers in diameter. Each particle carries carboxyl (–COOH) groups on its surface that are ionized at physiological pH, creating a stable negative charge. This carboxylation enables straightforward chemical coupling of proteins, peptides, antibodies, and other ligands via carbodiimide or other standard chemistries. The beads' micrometer size makes them easy to handle and ideal for immunoassays, diagnostic platforms, and flow cytometry applications where larger particles are preferred over nanoparticles.\u003c\/p\u003e\n\u003cdiv style=\"overflow-x:auto; max-width:100%; margin-bottom:20px;\"\u003e\n\u003ctable style=\"width:100%; max-width:640px; border-collapse:collapse;\"\u003e\n\u003ctbody\u003e\n\u003ctr style=\"border-bottom:1px solid #ddd;\"\u003e\n\u003ctd style=\"width:150px; padding:6px 10px 6px 0; vertical-align:top;\"\u003e\u003cstrong\u003eCatalog number:\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"padding:6px 0;\"\u003eB2025494\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"border-bottom:1px solid #ddd;\"\u003e\n\u003ctd style=\"width:150px; padding:6px 10px 6px 0; vertical-align:top;\"\u003e\u003cstrong\u003eLot number:\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"padding:6px 0;\"\u003eBatch dependent\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"border-bottom:1px solid #ddd;\"\u003e\n\u003ctd style=\"width:150px; padding:6px 10px 6px 0; vertical-align:top;\"\u003e\u003cstrong\u003eExpiration Date:\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"padding:6px 0;\"\u003eBatch dependent\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"border-bottom:1px solid #ddd;\"\u003e\n\u003ctd style=\"width:150px; padding:6px 10px 6px 0; vertical-align:top;\"\u003e\u003cstrong\u003eAmount:\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"padding:6px 0;\"\u003e5 mL\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"border-bottom:1px solid #ddd;\"\u003e\n\u003ctd style=\"width:150px; padding:6px 10px 6px 0; vertical-align:top;\"\u003e\u003cstrong\u003eSize range:\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"padding:6px 0;\"\u003e5.0–5.9 µm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"border-bottom:1px solid #ddd;\"\u003e\n\u003ctd style=\"width:150px; padding:6px 10px 6px 0; vertical-align:top;\"\u003e\u003cstrong\u003eMaterial:\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"padding:6px 0;\"\u003ePolystyrene latex\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"border-bottom:1px solid #ddd;\"\u003e\n\u003ctd style=\"width:150px; padding:6px 10px 6px 0; vertical-align:top;\"\u003e\u003cstrong\u003eSurface charge:\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"padding:6px 0;\"\u003eNegative (carboxylated)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"border-bottom:1px solid #ddd;\"\u003e\n\u003ctd style=\"width:150px; padding:6px 10px 6px 0; vertical-align:top;\"\u003e\u003cstrong\u003eSupplied as:\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"padding:6px 0;\"\u003eAqueous suspension\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"border-bottom:1px solid #ddd;\"\u003e\n\u003ctd style=\"width:150px; padding:6px 10px 6px 0; vertical-align:top;\"\u003e\u003cstrong\u003eApplications:\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"padding:6px 0;\"\u003eImmunoassay development, antibody immobilization, diagnostic assay platforms, flow cytometry, bead-based biosensors, affinity capture, solid-phase assays\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"border-bottom:1px solid #ddd;\"\u003e\n\u003ctd style=\"width:150px; padding:6px 10px 6px 0; vertical-align:top;\"\u003e\u003cstrong\u003eStorage:\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"padding:6px 0;\"\u003e2–8°C\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"border-bottom:1px solid #ddd;\"\u003e\n\u003ctd style=\"width:150px; padding:6px 10px 6px 0; vertical-align:top;\"\u003e\u003cstrong\u003eKeywords:\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"padding:6px 0;\"\u003eCarboxylated polystyrene beads, carboxyl latex microspheres, polystyrene microbeads, solid-phase beads, immunoassay beads, antibody-coated beads, diagnostic beads, protein-binding microspheres\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"border-bottom:1px solid #ddd;\"\u003e\n\u003ctd style=\"width:150px; padding:6px 10px 6px 0; vertical-align:top;\"\u003e\u003cstrong\u003eGrade:\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"padding:6px 0;\"\u003eBiotechnology grade. All products are highly pure. All solutions are made with Type I ultrapure water (resistivity \u0026gt;18 MΩ-cm) and are filtered through 0.22 µm.\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/div\u003e\n\u003ch3 style=\"margin-top:30px;\"\u003eScientific Overview\u003c\/h3\u003e\n\u003cp\u003ePolystyrene has been the material of choice for bead-based diagnostics and immunoassays for decades because of its chemical stability, uniform synthesis at defined sizes, straightforward chemical modification, and ease of handling in automated systems. Carboxylation via copolymerization with methacrylic acid or post-synthetic treatment adds ionizable surface groups that are negatively charged at physiological pH. This negative charge stabilizes the suspension against aggregation (through electrostatic repulsion) and provides a chemical handle for ligand attachment via carbodiimide-mediated coupling or other conjugation chemistries.\u003c\/p\u003e\n\u003cp\u003eAt 5–6 µm, these beads occupy a sweet spot for many applications: they are large enough to be convenient for pipetting and flow cytometry, yet small enough that their surface-area-to-volume ratio supports efficient protein binding and rapid assay kinetics. This size range is particularly well-suited to immunoassays, where beads serve as a solid phase for antibody or antigen capture, and to bead-based sensors used in point-of-care diagnostics.\u003c\/p\u003e\n\u003cp\u003eKey applications include:\u003c\/p\u003e\n\u003cul style=\"padding-left:20px;\"\u003e\n\u003cli\u003eSolid-phase immunoassays (sandwich ELISA, competitive assays, radioimmunoassays)\u003c\/li\u003e\n\u003cli\u003eAntibody immobilization for capture-based diagnostics\u003c\/li\u003e\n\u003cli\u003eFlow cytometry and cell sorting with antibody-coated beads\u003c\/li\u003e\n\u003cli\u003eBead-based biosensors and diagnostic platforms\u003c\/li\u003e\n\u003cli\u003eAffinity purification and biomolecule capture\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3 style=\"margin-top:30px;\"\u003eUsage \u0026amp; Handling Guidance\u003c\/h3\u003e\n\u003cp\u003eStore the suspension at 2–8°C in the original container. Invert several times before use to ensure even distribution. For protein coating, dilute the beads into ultrapure water or phosphate-buffered saline and activate with carbodiimide (e.g., 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide, or EDAC) and N-hydroxysuccinimide (NHS) to form reactive esters on the carboxyl groups, then incubate with the target protein. Specific coupling protocols depend on the protein's pI, concentration, and desired coating density; optimization may be required for your application.\u003c\/p\u003e\n\u003cul style=\"padding-left:20px;\"\u003e\n\u003cli\u003e\n\u003cstrong\u003eActivation:\u003c\/strong\u003e Use EDAC\/NHS chemistry to convert carboxyl groups to reactive N-hydroxysuccinimide esters for amine-coupling. Follow published protocols for your target biomolecule.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCoupling efficiency:\u003c\/strong\u003e Depends on protein concentration, pH, ionic strength, and incubation time. Test coupling with your specific antibody or protein to determine optimal conditions.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWashing:\u003c\/strong\u003e After coupling, wash beads multiple times with PBS or storage buffer to remove excess reactants and unbound protein.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBead concentration:\u003c\/strong\u003e Optimize bead concentration for your assay format (typically 10⁶ to 10⁸ beads\/mL depending on the application).\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3 style=\"margin-top:30px;\"\u003eWhat You Get\u003c\/h3\u003e\n\u003cul style=\"padding-left:20px;\"\u003e\n\u003cli\u003e5 mL of carboxylated polystyrene latex bead suspension\u003c\/li\u003e\n\u003cli\u003eUniform 5.0–5.9 µm particles with well-defined negative surface charge\u003c\/li\u003e\n\u003cli\u003eA convenient starting material for immunoassay development and diagnostic platform design\u003c\/li\u003e\n\u003cli\u003eFor research use only (RUO)\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3 style=\"margin-top:30px;\"\u003eWhy Researchers Choose It\u003c\/h3\u003e\n\u003cul style=\"padding-left:20px;\"\u003e\n\u003cli\u003eUniform, well-characterized size distribution ideal for immunoassays\u003c\/li\u003e\n\u003cli\u003eStraightforward surface chemistry for protein and antibody immobilization\u003c\/li\u003e\n\u003cli\u003eConvenient micrometer size for handling and flow cytometry\u003c\/li\u003e\n\u003cli\u003eProven track record in solid-phase immunoassays and diagnostics\u003c\/li\u003e\n\u003cli\u003eStable aqueous suspension ready to use\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3 style=\"margin-top:30px;\"\u003eFrequently Asked Questions (FAQ)\u003c\/h3\u003e\n\u003cul style=\"padding-left:20px;\"\u003e\n\u003cli\u003e\n\u003cstrong\u003eHow do I couple antibodies to the beads?\u003c\/strong\u003e\u003cbr\u003eActivate the carboxyl groups using EDAC\/NHS chemistry to form reactive succinimide esters, then incubate with your antibody of interest. The amine groups (typically at lysine residues and the N-terminus) on your antibody will form amide bonds with the activated carboxyls. Optimize pH, temperature, and incubation time for efficient coupling.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWhat is the binding capacity?\u003c\/strong\u003e\u003cbr\u003eBinding capacity depends on the target protein's size and the desired coating density. Test with your specific antibody to determine optimal protein coverage and binding capacity for your assay.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAre these beads suitable for automated systems?\u003c\/strong\u003e\u003cbr\u003eYes. The uniform size and density allow them to be used in automated microplate readers and liquid handling systems. Consult the system's documentation for bead compatibility.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCan I use these for flow cytometry?\u003c\/strong\u003e\u003cbr\u003eYes. The micrometer size is ideal for flow cytometry. Fluorescent labeling protocols are well-established in the literature, and antibody-coated beads are commonly used as positive controls or in bead-based assays.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eHow should I store coated beads?\u003c\/strong\u003e\u003cbr\u003eStore coated beads at 2–8°C in storage buffer (typically PBS with 0.02% sodium azide as a preservative). Do not freeze unless specifically indicated.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCan I get a TDS or COA?\u003c\/strong\u003e\u003cbr\u003eYes. Request a quote or contact us and we will provide available lot documentation.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cdiv style=\"margin-top:20px; font-weight:bold; color:#c8102e;\"\u003eThis product is for Research Use Only (RUO). It is not intended for diagnostic or therapeutic use in humans or animals.\u003c\/div\u003e\n\u003chr\u003e\n\u003ch4\u003eReferences\u003c\/h4\u003e\n\u003cul style=\"padding-left:0; margin:0; list-style:none;\"\u003e\n\u003cli style=\"display:flex; justify-content:space-between; align-items:flex-start; gap:12px; padding:8px 0; border-bottom:1px solid #eee;\"\u003e\n\u003cspan style=\"flex:1;\"\u003eGupta SK, Guesdon JL, Avrameas S, Talwar GP. Sandwich enzyme immunoassay of human chorionic gonadotropin using polystyrene beads as solid support. \u003cem\u003eAnn Inst Pasteur Immunol (1985).\u003c\/em\u003e 1985;136D(1):47-55.\u003c\/span\u003e\u003ca href=\"https:\/\/doi.org\/10.1016\/s0769-2625(85)80074-x\" target=\"_blank\" rel=\"noopener\" style=\"flex-shrink:0; margin-top:2px;\"\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0896\/1579\/4474\/files\/Reference.png?v=1775409336\" alt=\"Reference\" style=\"height:28px; width:auto;\"\u003e\u003c\/a\u003e\n\u003c\/li\u003e\n\u003cli style=\"display:flex; justify-content:space-between; align-items:flex-start; gap:12px; padding:8px 0; border-bottom:1px solid #eee;\"\u003e\n\u003cspan style=\"flex:1;\"\u003eHashida S, Ishikawa S, Nakamoto H, Tanaka S, Kojima M, Ishikawa E. Simple and more sensitive immune complex transfer enzyme immunoassay for antibody IgG to reverse transcriptase of HIV-1 using microplates, modified polystyrene solid phase and fluororeader. \u003cem\u003eJ Clin Lab Anal.\u003c\/em\u003e 1996;10(5):294-301.\u003c\/span\u003e\u003ca href=\"https:\/\/doi.org\/10.1002\/(SICI)1098-2825(1996)10:5\u0026lt;294::AID-JCLA10\u0026gt;3.0.CO;2-S\" target=\"_blank\" rel=\"noopener\" style=\"flex-shrink:0; margin-top:2px;\"\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0896\/1579\/4474\/files\/Reference.png?v=1775409336\" alt=\"Reference\" style=\"height:28px; width:auto;\"\u003e\u003c\/a\u003e\n\u003c\/li\u003e\n\u003cli style=\"display:flex; justify-content:space-between; align-items:flex-start; gap:12px; padding:8px 0; border-bottom:1px solid #eee;\"\u003e\n\u003cspan style=\"flex:1;\"\u003eSchoof E, John MR, Arndt B, Gao P, Theuer D, Sieg A, Schmidt-Gayk H. Solid phase competitive luminescence immunoassay for immunoglobulin A in faeces: development and clinical validation. \u003cem\u003eClin Chim Acta.\u003c\/em\u003e 1997;261(1):1-17.\u003c\/span\u003e\u003ca href=\"https:\/\/doi.org\/10.1016\/s0009-8981(96)06510-2\" target=\"_blank\" rel=\"noopener\" style=\"flex-shrink:0; margin-top:2px;\"\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0896\/1579\/4474\/files\/Reference.png?v=1775409336\" alt=\"Reference\" style=\"height:28px; width:auto;\"\u003e\u003c\/a\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n  \u003c\/div\u003e\n\u003c\/div\u003e","brand":"Molecular Depot","offers":[{"title":"Default Title","offer_id":52813555335466,"sku":"BTS-B2025494","price":1225.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0896\/1579\/4474\/files\/B2025494.png?v=1790897713","url":"https:\/\/bluetigerscientific.com\/products\/carboxylated-polystyrene-latex-beads-5-0-5-9-um","provider":"Blue Tiger Scientific","version":"1.0","type":"link"}