{"product_id":"carboxylate-modified-polystyrene-latex-beads-1-0-1-9-um","title":"Carboxylate-Modified Polystyrene Latex Beads, 1.0–1.9 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;\"\u003eCarboxylate-Modified Polystyrene Latex Beads, 1.0–1.9 µm – Catalog #B202644\u003c\/h2\u003e\n\u003cp\u003eCarboxylate-Modified Polystyrene Latex Beads (Catalog #B202644) are monodisperse polystyrene microspheres functionalized with carboxyl groups. At 1.0–1.9 µm diameter supplied as a 5 mL suspension, they represent an optimal size for many immunoassay platforms, offering a good balance between surface-area density and handling characteristics. The reactive carboxyl groups support covalent protein coupling via EDC\/NHS (1-ethyl-3-(3-dimethylaminopropyl)carbodiimide and N-hydroxysuccinimide) or carbodiimide-mediated chemistry, enabling immobilization of antibodies, antigens, and other protein ligands for diagnostic and research applications.\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;\"\u003eB202644\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;\"\u003e1.0–1.9 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\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, antibody immobilization, affinity capture, flow cytometry, serology\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, microbeads, immunoassay beads, protein coupling beads, EDC-activatable microspheres, carboxyl-functionalized polystyrene, conjugation beads\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 are the workhorse of bead-based immunoassays and affinity capture workflows. The surface carboxyl groups (-COOH) are readily activated by EDC, which converts them to a highly reactive acyl urea intermediate. This intermediate reacts with primary amines (mainly lysine residues and N-termini) on proteins, forming stable amide bonds. At 1.0–1.9 µm diameter, these beads are large enough to be easily separated and manipulated by standard magnetic or centrifugal methods, yet small enough to maintain significant surface area per particle.\u003c\/p\u003e\n\u003cp\u003eThe mid-range size is particularly popular in clinical and research settings because it provides:\u003c\/p\u003e\n\u003cul style=\"padding-left:20px;\"\u003e\n\u003cli\u003eSufficient surface area for adequate ligand loading (typically 500–2000 protein copies per bead)\u003c\/li\u003e\n\u003cli\u003eGood flowability in automated systems and pipetting\u003c\/li\u003e\n\u003cli\u003eEasy visualization and recovery in microtiter assays\u003c\/li\u003e\n\u003cli\u003eCompatibility with standard ELISA, flow cytometry, and plate-reader instrumentation\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eKey applications include:\u003c\/p\u003e\n\u003cul style=\"padding-left:20px;\"\u003e\n\u003cli\u003eSandwich immunoassays and multiplex serology\u003c\/li\u003e\n\u003cli\u003eCapture and purification of proteins and antibodies\u003c\/li\u003e\n\u003cli\u003eAffinity-based bioseparations and biomarker enrichment\u003c\/li\u003e\n\u003cli\u003eFlow cytometry and bead-based phenotyping\u003c\/li\u003e\n\u003cli\u003eOne-step immunoprecipitation workflows\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. Before use, gently mix (invert the tube 10–20 times) to resuspend the beads evenly. Do not vortex intensely or sonicate, as this may promote aggregation or damage the particles.\u003c\/p\u003e\n\u003cul style=\"padding-left:20px;\"\u003e\n\u003cli\u003e\n\u003cstrong\u003eEDC conjugation:\u003c\/strong\u003e Dissolve EDC (e.g., 10–50 mM) in pH 5–6 coupling buffer, add beads, and incubate 15–30 minutes with gentle mixing to activate carboxyl groups. Add protein (50–500 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\u003eQuenching:\u003c\/strong\u003e Stop the reaction by adding ethanolamine (1 M, pH 8.5) or Tris-HCl (1 M, pH 8) and incubating 10 minutes. This prevents non-specific adsorption and improves assay background.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWashing:\u003c\/strong\u003e Recover beads by centrifugation (brief, 2–3 min at 1,000–2,000 g), remove supernatant, and resuspend in wash buffer (PBS with 0.1% Tween-20 or equivalent). Repeat 2–3 times.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBlocking:\u003c\/strong\u003e Optionally block remaining hydrophobic polystyrene surface with BSA (1–5%), gelatin, or non-fat milk to reduce non-specific binding.\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 1.0–1.9 µm diameter\u003c\/li\u003e\n\u003cli\u003eSupplied as ready-to-use suspension\u003c\/li\u003e\n\u003cli\u003eReactive carboxyl groups suitable for EDC\/NHS conjugation\u003c\/li\u003e\n\u003cli\u003eOptimal size for immunoassays and flow cytometry\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\u003eMid-range size is the industry standard for sandwich immunoassays and serology\u003c\/li\u003e\n\u003cli\u003eHigh-quality polystyrene provides excellent optical clarity and brightness in fluorescence assays\u003c\/li\u003e\n\u003cli\u003eReactive carboxyl surface enables fast, efficient protein coupling\u003c\/li\u003e\n\u003cli\u003eExcellent batch-to-batch consistency and size uniformity\u003c\/li\u003e\n\u003cli\u003eProven performance in published methods for multiplex immunoassays and bead-based flow cytometry\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 should I activate the carboxyl groups before adding protein?\u003c\/strong\u003e\u003cbr\u003eIncubate the beads in EDC solution (10–50 mM in pH 5–6 buffer) for 15–30 minutes. For longer shelf-life of the activated beads, use EDC + NHS together; NHS esters are more stable intermediates than the EDC-urea adduct.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eHow much protein should I use per bead?\u003c\/strong\u003e\u003cbr\u003eTypical protein concentrations range 50–500 µg\/mL. For small proteins (\u0026lt; 40 kDa), use higher concentrations; for large proteins or antibodies (\u0026gt; 150 kDa), use lower concentrations. Empirically determine optimal coating by measuring bound protein.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWhat is the expected coupling efficiency?\u003c\/strong\u003e\u003cbr\u003eEDC-mediated coupling typically achieves 70–95% efficiency, depending on protein concentration, pH, and incubation time. Request a COA for lot-specific coupling validation, or determine empirically using fluorescently labeled or biotinylated protein.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCan I re-use the beads after washing?\u003c\/strong\u003e\u003cbr\u003eProtein-coupled beads are designed for single use in assays. However, you can prepare fresh conjugates for each experiment and store coupled beads at 2–8°C with preservative (0.02% sodium azide or Proclin) for a few months.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eHow do these beads compare to magnetic beads?\u003c\/strong\u003e\u003cbr\u003eNon-magnetic beads like these are ideal when magnetic field separation is not needed (e.g., ELISA, some flow cytometry). Magnetic beads are preferred for high-throughput separation and isolation workflows.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAre there smaller or larger versions available?\u003c\/strong\u003e\u003cbr\u003eYes. Blue Tiger Scientific offers carboxylate-modified polystyrene beads in a range of sizes: 0.6–1.0 µm (higher surface area, better for sensitive assays), 1.0–1.9 µm (this product, best for general use), 2.0–2.9 µm, and \u0026gt;10 µm (easier handling, lower surface area).\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":52809024176426,"sku":"BTS-B202644","price":935.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0896\/1579\/4474\/files\/B202644.png?v=1790859900","url":"https:\/\/bluetigerscientific.com\/products\/carboxylate-modified-polystyrene-latex-beads-1-0-1-9-um","provider":"Blue Tiger Scientific","version":"1.0","type":"link"}