{"product_id":"carboxylate-modified-polystyrene-latex-beads-2-0-2-9-um-2-5-w-v","title":"Carboxylate-Modified Polystyrene Latex Beads, 2.0–2.9 µm, 2.5% w\/v","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;\"\u003eCarboxylate-Modified Polystyrene Latex Beads, 2.0–2.9 µm, 2.5% w\/v – Catalog #B2025731\u003c\/h2\u003e\n\u003cp\u003eCarboxylate-Modified Polystyrene Latex Beads (Catalog #B2025731) are monodisperse polystyrene microspheres functionalized with surface carboxyl groups. Supplied at 2.0–2.9 µm diameter in a 5 mL suspension at 2.5% w\/v, they balance reasonable surface area with excellent handling and optical properties. The larger diameter makes these beads ideally suited for applications where particle visibility, easy resuspension, and straightforward magnetic separation are important, including immunoassays, flow cytometry, and one-step biomarker isolation. Carboxyl groups are readily activated by EDC\/NHS chemistry for covalent immobilization of antibodies, antigens, and other protein ligands.\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;\"\u003eB2025731\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\u003eBead diameter:\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"padding:6px 0;\"\u003e2.0–2.9 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\u003eConcentration:\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"padding:6px 0;\"\u003e2.5% w\/v\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;\"\u003eSuspension\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\u003eComposition:\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"padding:6px 0;\"\u003ePolystyrene with carboxylate surface groups\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;\"\u003eImmunoassays, protein coupling, EDC\/NHS conjugation, flow cytometry, immunoprecipitation, affinity separations, magnetic bead workflows\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;\"\u003eCarboxylate-modified polystyrene, carboxyl latex beads, larger microbeads, immunoassay beads, protein coupling beads, visible microspheres, EDC-activatable beads, affinity particles\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\u003eCarboxylate-modified polystyrene latex beads at 2.0–2.9 µm diameter represent a practical choice for researchers who need good optical and handling characteristics alongside functional protein-coupling capability. At this size, each bead maintains substantial surface area (approximately 25–65 µm² depending on exact diameter), allowing for loading of 500–2000 protein molecules per particle. Yet the larger diameter provides distinct advantages: the beads are individually resolvable by light microscopy, settle and resuspend more readily, and are easily recovered by brief centrifugation.\u003c\/p\u003e\n\u003cp\u003eThe carboxyl surface groups are activated by EDC (1-ethyl-3-(3-dimethylaminopropyl)carbodiimide), which forms a reactive acyl-urea intermediate that reacts with primary amines on proteins. This straightforward coupling chemistry has been the standard in immunoassay development for decades.\u003c\/p\u003e\n\u003cp\u003eKey applications include:\u003c\/p\u003e\n\u003cul style=\"padding-left:20px;\"\u003e\n\u003cli\u003eImmunoassay development and optimization (ELISA, sandwich assays, multiplex formats)\u003c\/li\u003e\n\u003cli\u003eImmunoprecipitation and co-immunoprecipitation (co-IP) workflows\u003c\/li\u003e\n\u003cli\u003eFlow cytometric analysis and fluorescence-based detection\u003c\/li\u003e\n\u003cli\u003eBiomarker capture and enrichment from blood or tissue lysates\u003c\/li\u003e\n\u003cli\u003eCompatibility with magnetic bead handlers when beads are coupled to ferrimagnetic cores\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3 style=\"margin-top:30px;\"\u003eUsage \u0026amp; Handling Guidance\u003c\/h3\u003e\n\u003cp\u003eStore at 2–8°C and protect from excessive agitation. Before use, gently invert the tube 5–10 times to evenly distribute beads. The larger size ensures good resuspension without intense vortexing or sonication.\u003c\/p\u003e\n\u003cul style=\"padding-left:20px;\"\u003e\n\u003cli\u003e\n\u003cstrong\u003eCoupling procedure:\u003c\/strong\u003e Activate beads with EDC (20–50 mM in pH 5–6 coupling buffer) for 15–30 minutes. Add protein (25–250 µg\/mL) and incubate 1–4 hours at 20°C or overnight at 4°C with gentle mixing.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSize benefits:\u003c\/strong\u003e The larger diameter allows use of standard microtiter wells and magnetic separators designed for beads in this size range (typically 1–5 µm). Beads settle predictably under gravity, simplifying washing protocols.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eParticle recovery:\u003c\/strong\u003e Centrifuge briefly (2–3 min at 1,000–3,000 g) to pellet beads. Magnetic separation is also effective, especially if beads are coated with or attached to magnetic particles.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eNon-specific binding control:\u003c\/strong\u003e Block remaining hydrophobic polystyrene surface with BSA (1–5%), gelatin, or a commercial blocking reagent to minimize background signal in assays.\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 carboxylate-modified polystyrene latex beads at 2.0–2.9 µm diameter\u003c\/li\u003e\n\u003cli\u003eSupplied at 2.5% w\/v suspension for convenient use\u003c\/li\u003e\n\u003cli\u003eReactive carboxyl groups suitable for EDC\/NHS conjugation\u003c\/li\u003e\n\u003cli\u003eLarger size for easy visualization and handling\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\u003eLarger diameter offers superior handling, visibility, and optical properties compared to sub-micron beads\u003c\/li\u003e\n\u003cli\u003eStill maintains adequate surface area for reasonable protein loading\u003c\/li\u003e\n\u003cli\u003eSimpler bead resuspension and recovery in standard laboratory workflows\u003c\/li\u003e\n\u003cli\u003eWell-suited for both manual and automated high-throughput assay platforms\u003c\/li\u003e\n\u003cli\u003eExcellent batch-to-batch consistency and monodispersity\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 does the larger size affect coupling?\u003c\/strong\u003e\u003cbr\u003eLarger beads have slightly lower surface-area-to-volume ratio than smaller beads, so you get 500–2000 protein molecules per bead instead of thousands. For most immunoassays, this is more than sufficient and offers the practical advantage of easier handling.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCan I use these with magnetic particle handlers?\u003c\/strong\u003e\u003cbr\u003eThese are non-magnetic polystyrene beads. However, they are commonly coated onto or attached to magnetic particles for use with automated magnetic separators. Consult our sales team for magnetic variants.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWhy might I choose 2.0–2.9 µm over 1.0–1.9 µm?\u003c\/strong\u003e\u003cbr\u003eThe larger size is preferred if you need better particle visibility, easier recovery by centrifugation or gravity sedimentation, or compatibility with instruments designed for slightly larger beads. Choose smaller beads if you need maximum assay sensitivity from higher ligand density.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eHow stable are protein-coupled beads?\u003c\/strong\u003e\u003cbr\u003eProtein-coupled beads are stable for at least several months at 2–8°C, or longer at −20°C if protected with cryoprotectant (50% glycerol or equivalent). Include an antimicrobial preservative (0.02% sodium azide or Proclin) to prevent microbial growth during extended storage.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCan I store unused activated beads?\u003c\/strong\u003e\u003cbr\u003eEDC-activated beads should be used promptly (typically within minutes to an hour) as the reactive intermediate decays. For longer shelf-life, activate with EDC + NHS together; NHS-ester intermediates are more stable and can be stored for hours if dry or in acidic conditions.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eHow many beads are in 5 mL at 2.5% w\/v?\u003c\/strong\u003e\u003cbr\u003eA 2.5% suspension contains approximately 2.5 g of beads per 100 mL. For a 2.5 µm sphere, this corresponds to roughly 10^11 to 10^12 particles per mL, but the exact count depends on bead density and size distribution. Request a COA for lot-specific particle concentration.\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;\"\u003eMolina-Bolívar JA, Galisteo-González F, Hidalgo-Alvarez R. Particle enhanced immunoassays stabilized by hydration forces: a comparative study between IgG and F(ab)2 immunoreactivity. \u003cem\u003eJ Immunol Methods.\u003c\/em\u003e 1998;211(1-2):87-95.\u003c\/span\u003e\u003ca href=\"https:\/\/doi.org\/10.1016\/s0022-1759(97)00189-0\" 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;\"\u003eFortin M, Hugo P. Surface antigen detection with non-fluorescent, antibody-coated microbeads: an alternative method compatible with conventional fluorochrome-based labeling. \u003cem\u003eCytometry.\u003c\/em\u003e 1999;36(1):27-35.\u003c\/span\u003e\u003ca href=\"https:\/\/pubmed.ncbi.nlm.nih.gov\/10331624\/\" 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;\"\u003eKamyshny A, Feldman A, Baszkin A, Boissonnade MM, Rosilio V V, Magdassi S. Chemically Modified Glucose Oxidase with Enhanced Hydrophobicity: Adsorption at Polystyrene, Silica, and Silica Coated by Lipid Monolayers. \u003cem\u003eJ Colloid Interface Sci.\u003c\/em\u003e 1999;218(1):300-308.\u003c\/span\u003e\u003ca href=\"https:\/\/doi.org\/10.1006\/jcis.1999.6440\" 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":52809024143658,"sku":"BTS-B2025731","price":705.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0896\/1579\/4474\/files\/B2025731.png?v=1790859895","url":"https:\/\/bluetigerscientific.com\/products\/carboxylate-modified-polystyrene-latex-beads-2-0-2-9-um-2-5-w-v","provider":"Blue Tiger Scientific","version":"1.0","type":"link"}