Carboxyl-functionalized upconverting nanoparticles - Em. Wavelength:660 nm,particle size:35nm,Coating:dSiO2-COOH

Cat. No.: C140948

GRADE & PURITY Em. Wavelength:660 nm,particle size:35nm,Coating:dSiO2-COOH

Synonyms

Functionalized UCNs

Storage

Room temperature

Shipped In

Normal

Visão geral

This series of products are carboxyl functionalized up-conversion nanoparticles. The material composition is NaYREF4 (RE:Yb, Er, Tm, Gd, Mn, Lu), and the best excitation wavelength is 975 nm. The sensitizing ion is Yb3+, and the activating ion is Er3+ or Tm3+. By adjusting the doping concentration of each ion, the luminescence of the product at a specific wavelength has been optimized. The surface-coated silica or PEG makes the nanoparticles have good hydrophilicity and can be directly dispersed in aqueous media. The product has uniform particle size, high luminous quantum efficiency and good light stability.
After proper surface modification and functionalization, the products can be used for fluorescence imaging, biodetection, immunity analysis and photoactivation of anti-cancer drugs and biomolecules.

Specifications

Sinónimos

Functionalized UCNs

Especificações e pureza

Em. Wavelength:660 nm,particle size:35nm,Coating:dSiO2-COOH

Condições de armazenamento de armazenamento

Room temperature

Enviado em

Normal

Application Protocols

Note: No item-specific tested applications or dilutions are provided. The following is general guidance for –COOH UCNP handling and conjugation (literature-based).

A. Dispersion and pre-cleaning

• Disperse nanoparticles at 0.5–2 mg/mL in 10–20 mM MES, pH 5.5. Sonicate in a bath sonicator 1–5 min to break soft agglomerates. Remove dust by low-speed centrifugation (e.g., 1,000–2,000 g, 2–5 min) and collect the supernatant.

B. EDC/sulfo-NHS coupling to amine ligands

• Activation: To the UCNP dispersion, add EDC to 10 mM and sulfo-NHS to 25 mM. Incubate 15–20 min at RT with gentle mixing.
• Buffer exchange: Rapidly exchange to PBS or HEPES, pH 7.2–7.4 (spin filtration, 50–100 kDa MWCO) to remove excess EDC by-products while retaining NHS-esters on the particle surface.
• Coupling: Add amine-bearing ligand at 2–20× molar excess relative to estimated –COOH sites; incubate 1–2 h at RT (or overnight at 4 °C for sensitive biomolecules).
• Quench: Add ethanolamine to 20 mM, 15 min. Wash 3–4× with storage buffer (PBS/HEPES) by centrifugation or ultrafiltration.

C. Stabilization and storage

• Optional: Add 0.01–0.05% Tween-20 and 0.1% BSA for storage to reduce aggregation and nonspecific binding (verify compatibility).

D. Basic photophysical measurement

• Excite at the appropriate NIR line for your UCNP (commonly 980 nm; 808 nm for Nd-sensitized systems—literature). Record emission spectra with an integrating sphere or corrected spectrofluorometer.

Parameters such as particle size, excitation wavelength, and –COOH density for this item are Not specified; optimize empirically.

Biological Roles

Applicability: This product is an inorganic nanomaterial and does not possess intrinsic biological roles or metabolic functions.

Research-relevant biological context (literature/general; no clinical claims):

• Photophysics compatible with bioassays: NIR excitation enables low autofluorescence and deeper optical penetration in tissues and turbid media relative to UV/visible excitation. Upconverted emission facilitates background-reduced detection in enzyme assays, immunoassays, and nucleic acid hybridization formats.
• Bioconjugation capacity: Surface –COOH groups allow covalent attachment of biomolecules (proteins, peptides, oligonucleotides, carbohydrates) through amide formation, enabling targeted binding in biochemical experiments.
• Enzymatic/chemical stability: UCNP cores resist photobleaching and are chemically robust under typical assay conditions, supporting prolonged or repeated measurements (literature).
• Colloidal behavior in biological buffers: Zeta potential and steric stabilization (via PEG or proteins) govern nonspecific adsorption and dispersion stability. Optimization with blockers (BSA, casein) or PEGylation can mitigate fouling.

Caveats:

• Cytotoxicity and biodistribution are system- and coating-dependent; evaluate in vitro compatibility specific to your application. No claims are made for in vivo use.
• Endotoxin content and microbial bioburden, if relevant to your assays, should be verified on the batch CoA or tested in-house.

Summary: Use –COOH UCNPs as photonic labels or energy donors in biochemical research after appropriate conjugation and validation. They serve as optical tools, not biological effectors.

Buffer Applications

Applicability: Relevant insofar as buffers control colloidal stability and govern carbodiimide coupling efficiency.

General buffer guidance (literature):

• Activation buffer: MES (20–100 mM, pH 5.0–6.5) is commonly used for EDC/NHS activation of surface carboxylates. Low nucleophilicity minimizes competing hydrolysis; moderate ionic strength (10–50 mM NaCl) can reduce electrostatic repulsion and improve reactant access.
• Coupling buffer: Switch to neutral buffers after activation (pH 7.0–7.5). PBS (0.5–1×), HEPES (20–50 mM), or carbonate (pH 8.3 for faster amine reactivity) are typical. Avoid primary amines (e.g., Tris) during the NHS-ester lifetime as they quench activation.
• Storage buffer (post-conjugation): HEPES or PBS at pH 7.2–7.6 with 0.01–0.05% nonionic surfactant (e.g., Tween-20) can suppress aggregation. Add 0.02–0.05% sodium azide only for non-biological applications; azide is incompatible with copper catalysis and certain proteins.
• Blocking agents: 0.1–1% BSA or casein can reduce nonspecific adsorption in immunoassay-type workflows; validate for spectral background.

Practical notes:

• Filter buffers (0.22 μm) to remove particulates prior to nanoparticle addition.
• Control ionic strength carefully; excessive salt compresses the double layer and may induce aggregation.
• Monitor zeta potential vs pH to map the stability window for your batch.

Item-specific details such as recommended buffer identities, concentrations, and stabilizers are Not specified for this item; refer to CoA/Spec Sheet.

Green Alternatives

Context: UCNPs are specialty inorganic nanomaterials containing rare-earth elements; “green” considerations focus on solvent/media choice, ligation chemistry, and lifecycle handling rather than substituting the core material.

Greener practice options (literature/general):

• Aqueous processing: Favor water and mild buffers (MES, HEPES) over high-boiling dipolar aprotic solvents. Avoid unnecessary surfactants; select biodegradable nonionics where needed.
• EDC/NHS over acid halides: Carbodiimide-mediated amidation in water avoids thionyl chloride/oxalyl chloride workflows and minimizes hazardous by-products.
• 808 nm excitation systems: If compatible with the UCNP sensitizer, 808 nm reduces water absorption heating vs 980 nm, improving energy efficiency and minimizing sample warming (application-dependent; literature).
• Recovery and reuse: Capture nanoparticles by centrifugation or membrane filtration for reuse. Implement closed-loop wash streams when feasible.
• Waste minimization: Aggregate and solidify nanoparticle-containing wastes for appropriate disposal; avoid dispersing to aqueous waste lines.

Illustrative comparison (general):

• Water/MES buffer vs DMF/DMSO-heavy coupling media: Similar coupling efficiencies achievable with EDC/NHS in MES (pH ~5.5) while reducing solvent hazard and facilitating cleanup.
• Carbodiimide chemistry vs acid chloride activation: Aqueous EDC/NHS produces urea by-products vs corrosive HCl and acyl chloride residues.

Trade-offs:

• Rare-earth sourcing has sustainability concerns; however, the high photostability and reusability of UCNPs can reduce probe replacement frequency in repetitive measurements (use-case dependent).

Pharmaceutical Uses

Applicability: This material is offered for research use only. No claims are made regarding suitability as an active ingredient or approved excipient.

Research/formulation context (literature/general):

• Model nanocarrier studies: Carboxylated UCNPs can serve as optical tracers in formulation research to track particle distribution, adsorption to excipients, or processing effects using their upconversion emission.
• Conjugation to excipient polymers: –COOH surfaces enable coupling to amine-bearing polymers (e.g., chitosan, PEI derivatives) to explore mucoadhesion, film formation, or depot behavior in in vitro models.
• Process development tools: Robust luminescence allows real-time monitoring of mixing, coating, or drying in process-analytical-technology (PAT) experiments.

Constraints and compliance:

• Pharmacopoeial status: No pharmacopeia listing is implied. Endotoxin/bioburden, residual solvents, and leachables/extractables would require independent qualification for any regulated use.
• Toxicological evaluation: Any safety profile is formulation- and surface-coating-dependent. This listing provides no toxicology certification.

Item-specific regulatory grade, sterility, and endotoxin limits: Not specified for this item; refer to CoA/Spec Sheet.

Conclusion: Use these nanoparticles as non-therapeutic optical probes or materials in pharmaceutical research and process studies, with appropriate in-house qualification.

Physical Properties

Item-specific (from Product Data):

• Molecular formula: Not specified for this item; refer to CoA/Spec Sheet.
• Molecular weight: Not specified for this item; refer to CoA/Spec Sheet.
• Particle size, surface density of -COOH, core composition, dopant levels, hydrodynamic size, zeta potential, emission maxima, quantum yield: Not specified for this item; refer to CoA/Spec Sheet.

General/literature characteristics for carboxylated UCNPs (illustrative—not item-specific):

• Physical state: Solid nanocrystals; often supplied as dry powder or stabilized aqueous dispersion.
• Density: Inorganic fluoride cores typically 3–5 g/cm³ (literature), but effective bulk density depends on surface coating and formulation.
• Solubility/dispersion: Carboxylated surfaces are dispersible in water and polar buffers above the pKa of surface acids; aggregation can occur at low ionic strength extremes or near the isoelectric point.
• Surface acidity: Apparent pKa of carboxylated polymer/silica shells commonly in the 4–5.5 range (literature), influencing colloidal charge with pH.
• Optical: Upconversion emission bands dependent on dopant; sensitizer absorption (e.g., Yb3+ around 980 nm) and possible 808 nm excitation with Nd3+ co-sensitization (literature).
• Thermal stability: Inorganic cores are thermally robust (>300 °C in inert environments); organic coatings can degrade significantly lower (literature). Avoid prolonged heating in air for coated materials.

Notes:

• Refractive index, melting/boiling points, and logP are not meaningful for intact nanoparticulates in the same way as for small molecules and are formulation-dependent (literature guidance).

Quality and Grades

Item-specific (from Product Data):

• Grade/purity: Not specified for this item; refer to CoA/Spec Sheet.

How to interpret quality for carboxylated UCNPs (general guidance):

• Purity dimensions: For nanomaterials, “purity” encompasses inorganic core composition (phase purity, dopant loading), absence of by-product phases (e.g., α- vs β-NaYF4), residual organics (oleate, surfactants), free ions, and endotoxin/bioburden if intended for bioassays. These parameters are typically reported on a CoA as XRD phase, ICP-OES/ICP-MS for elemental ratios, TGA for organic content, and DLS/EM for size distribution (literature conventions).
• Surface functionality quality: Carboxyl surface density (μmol –COOH per g or per particle), coupling efficiency metrics (e.g., via EDC/NHS test reactions with amine probes), and zeta potential vs pH provide functional performance indicators.
• Optical performance: Emission spectra under specified excitation (980/808 nm), relative quantum yield, and photostability under continuous-wave irradiation are practical quality metrics. Batch-to-batch emission consistency and core–shell integrity (if applicable) are important for reproducible assays.
• Low-UV/low-fluorescence solvent claims (HPLC grade, etc.) are not relevant to this product class.

Recommendations:

• Request CoA data for crystal phase, dopant levels, –COOH surface density, dispersion medium (if supplied as a suspension), and any preservative. Validate application-specific criteria (bioconjugation yield, zeta potential, colloidal stability) in your lab prior to scale-up.

Reaction and Applications

Scope: As functional nanomaterials, these UCNPs serve as platforms for surface reactions rather than undergoing classical organic transformations.

Typical applications (literature/general):

• Bioconjugation via carboxylates: EDC/NHS chemistry to couple primary amines on proteins, peptides, DNA, polymers, or surfaces, forming stable amide linkages. Carbodiimide activation in mildly acidic buffers (MES, pH 5–6.5), followed by coupling at neutral pH.
• Click-ready derivatization: Conversion of –COOH to azides/alkynes through amide linkers; enables CuAAC or SPAAC for modular assembly of probes, targeting ligands, or polymers.
• Thin film and composite fabrication: Disperse –COOH UCNPs into carboxyl/amine-functional polymers (e.g., PAA, PVA, chitosan) for luminescent coatings, security inks, and photonic devices.
• Energy transfer constructs: Assemble FRET/UCNP-based sensors where surface –COOH enables precise donor–acceptor spacing with dyes or quenchers (literature).
• Micro/nanopatterning: Inkjet or microcontact printing of aqueous dispersions onto substrates prefunctionalized with amines or epoxies; post-print curing via carbodiimide crosslinking.

Practical tips:

• Maintain colloidal stability during reactions: low to moderate ionic strength; avoid primary amines or high phosphate during NHS-ester formation.
• Quantify coupling: Use amine-reactive probes (e.g., fluorescamine post-coupling to residual amines on counterpart) or ninhydrin assays on supernatants.
• Photostability: UCNP cores are resistant to photobleaching; nonetheless, minimize thermal load from high-power NIR sources to preserve organic coatings.

Note: Specific emission wavelengths, particle sizes, and surface group densities for this item are Not specified; optimize conditions empirically.

Reaction Conditions

General coupling conditions for –COOH UCNPs (literature guidance; not item-specific):

• EDC/NHS amidation:
  • Dispersion: 0.1–2 mg/mL nanoparticles in 20–100 mM MES buffer, pH 5.0–6.0.
  • Activation: Add EDC (2–20 mM) and NHS or sulfo-NHS (5–50 mM). React 10–30 min at 20–25 °C with gentle mixing. Avoid primary amines and high phosphate during this step.
  • Coupling: Exchange to pH 7.2–7.5 buffer (PBS/HEPES) or increase pH by addition of concentrated buffer; add amine partner at 0.05–2 mM (or excess relative to estimated –COOH sites). React 1–4 h at 20–25 °C.
  • Quench/wash: Quench unreacted NHS-esters with ethanolamine (10–50 mM), then wash via centrifugation or ultrafiltration.
• DMTMM-mediated amidation (aqueous, amine-friendly): 2–10 mM DMTMM at pH 7–8 for 1–3 h; compatible with many buffers; monitor for background reactions.
• Carbodiimide in organic media (if dispersion allows): CDI or EDC/DMAP in DMF/DMSO for alcohol coupling; ensure coating integrity and colloidal stability.

Analytical controls:

• Track activation via TNBS assay on unreacted amines (counterpart) or by measuring released NHS after quench.
• Confirm conjugation by shift in hydrodynamic diameter (DLS), zeta potential, and presence of cargo by UV–Vis/fluorescence or ICP for labels.

Yields: Reported conjugation efficiencies vary widely (20–90%, literature) depending on surface density and sterics.

Temperature/light: Room temperature is typical. Protect samples from dust and unnecessary visible light during photophysical measurements; NIR excitation should be moderated to avoid local heating.

Item-specific optimal conditions and capacities are Not specified; validate on small scale.

Safety and Handling

Item-specific (from Product Data):

• GHS signal word: Not specified for this item; refer to SDS.
• H-statements and GHS classification: Not specified for this item; refer to SDS.
• Pictograms: Not specified for this item; refer to SDS.
• Storage: Room temperature; shipped under normal conditions.

General safety considerations (literature/good laboratory practice):

• Nanoparticle-specific precautions: Avoid generating dust/aerosols. Use local exhaust ventilation or a fume hood; consider nanoparticle-rated respirators if airborne exposure is possible. Prevent release to drains without appropriate capture/filtration.
• PPE: Safety glasses, lab coat, and suitable chemical-resistant gloves. For powders, consider disposable sleeve covers and work over wet benches or use pre-wetted wipes for cleanup.
• Incompatibilities: Strong oxidizers may degrade organic coatings; strong acids/bases can strip surface ligands or etch shells (especially silica or polymer layers). Halogenated oxidants and fluoride-complexing reagents can alter fluoride-based cores (literature).
• First aid (overview; defer to SDS): If inhaled—move to fresh air; seek medical attention if symptoms persist. Skin/eye contact—rinse with water for several minutes; remove contaminated clothing. Ingestion—rinse mouth; seek medical advice.
• Fire/reactivity: Inorganic UCNP cores are non-flammable; organic surface ligands and polymer/silane shells are combustible. Use standard extinguishing media (CO2, dry chemical, water fog) appropriate for surrounding fire.
• Environmental: Rare-earth-containing particulates should be collected as solid waste; follow institutional nanomaterials disposal procedures.

Always consult the product-specific SDS for authoritative hazard and exposure information.

Solvent Selection

Applicability: This product is a nanoparticulate solid or dispersion; “solvent selection” pertains to dispersion media rather than molecular solubility.

General guidance (literature):

• Polarity and pH: Carboxylated UCNPs typically disperse well in water and polar buffers where –COO− forms above the apparent pKa (~4–5.5, literature). Moderate ionic strength (5–50 mM) can screen charges; optimize to avoid aggregation.
• Common media:
  • Deionized water: Baseline dispersion; adjust pH to 6.5–8.0 for stable negative zeta potential.
  • Phosphate-buffered saline (PBS, pH 7.2–7.4): Bioconjugation-compatible, but high salt can compress the double layer; consider 0.5× PBS during coupling to limit aggregation.
  • MES buffer (pH 5.0–6.5): Preferred for EDC/NHS activation of carboxylates; low nucleophilicity reduces side reactions.
  • HEPES or Tris (pH 7.2–8.0): Post-conjugation storage; note Tris can quench NHS-esters and should be avoided during activation.
• Organic cosolvents: Small percentages (≤10–20% v/v) of ethanol or isopropanol can aid wetting; avoid strong hydrogen-bond donors that disrupt coatings. DMSO can be used to solubilize ligands prior to addition, but high fractions may destabilize dispersions (literature).
• Surfactants: Nonionic surfactants (e.g., Tween-20, Pluronic F127) can enhance colloidal stability; verify impact on downstream assays.

Selection tips:

• For bioconjugation: Use MES (pH ~5.5) for activation, then exchange into PBS/HEPES for coupling.
• For photophysical testing: Employ low-fluorescence water/buffer; eliminate particulates via 0.22 μm filtration of the medium before adding nanoparticles.

Storage and Reconstitution

Item-specific (from Product Data):

• Storage conditions: Room temperature
• Shipped in: Normal

General guidance (literature/best practice):

• Dry powders: Store tightly closed in clean, inert containers at ambient temperature away from moisture and direct light. Include a desiccant to limit humidity. Avoid repeated opening that may introduce airborne contaminants.
• Aqueous dispersions: If reconstituted, store at 2–8 °C for medium-term stability unless otherwise validated at RT. Do not freeze unless the dispersion contains cryoprotectants (e.g., 10–20% glycerol or suitable polymers), as ice crystallization can induce aggregation.
• Reconstitution: Wet powders first with a small amount of ethanol or buffer containing 0.01% nonionic surfactant, then dilute into the target buffer (e.g., MES, PBS, HEPES). Sonicate briefly (1–5 min bath sonication). Filter media (0.22 μm) before addition to reduce dust nucleation sites.
• Working stocks: Prepare at 0.1–2 mg/mL. For bioconjugation, use freshly prepared dispersions to maximize reactive –COOH availability and minimize adventitious adsorption.
• Light and thermal considerations: Protect from excessive heat and prolonged high-power NIR irradiation outside of measurement periods to preserve organic coatings.
• Stability checks: Monitor hydrodynamic diameter (DLS) and zeta potential after storage; if aggregation is detected, re-sonicate gently and consider buffer exchange.

Any stabilizers, preservatives, or exact shelf-life for this item are Not specified; refer to CoA/Spec Sheet and product SDS for definitive guidance.

Structure and Identity

Overview: Carboxyl-functionalized upconverting nanoparticles (UCNPs) are inorganic nanocrystals whose surfaces present terminal carboxyl (-COOH) groups for covalent coupling and dispersion control. They convert near-infrared (NIR) excitation to higher-energy visible emission via multiphoton processes in lanthanide-doped hosts.

Item-specific (from Product Data):

• Product name: Carboxyl-functionalized upconverting nanoparticles (SKU: C140948)
• Storage conditions: Room temperature
• Shipment: Normal
• Research use note: For research use only
• Molecular formula, molecular weight, CAS, InChIKey, SMILES: Not applicable/Not specified for this item; refer to CoA/Spec Sheet.

General structural features (literature, illustrative—not item-specific):

• Core composition: Common UCNP cores include NaYF4 doped with Yb3+ (sensitizer) and Er3+, Tm3+, or Ho3+ (emitters); other hosts (e.g., NaGdF4, CaF2) are also used.
• Architecture: Typically spherical to sub-spherical nanocrystals; optionally core–shell structures (e.g., NaYF4:Yb,Er@NaYF4) to enhance quantum yield and suppress surface quenching.
• Surface chemistry: Terminal -COOH groups provided via ligand exchange or polymer/silane shells (e.g., poly(acrylic acid), carboxylated silica), enabling EDC/NHS coupling to primary amines on biomolecules, polymers, or surfaces.
• Optical identity: Anti-Stokes (upconversion) emission; canonical bands for Er3+ (green ~540 nm, red ~650 nm), Tm3+ (blue ~450 nm, NIR ~800 nm), Ho3+ (green ~540 nm), when excited at 980 nm or 808 nm via sensitizers (literature).

2D/chemical description in words (general): Inorganic fluoride lattice embedding trivalent lanthanide ions; outer corona bearing multiple pendant carboxyl groups accessible to aqueous media and covalent conjugation.

Synthetic Utility

Role in synthesis: Carboxyl-functionalized UCNPs are modular, light-emitting scaffolds for building hybrid materials via surface chemistry.

Key functional handles and reactivity (literature/general):

• Carboxylates (–COOH): Form amide bonds with primary amines via carbodiimide (EDC/NHS) coupling; esterification with alcohols (less common in aqueous systems) using carbodiimide/DMAP in aprotic media when compatible.
• Sequential functionalization: –COOH → NHS-ester → amide to install linkers bearing azide/alkyne, maleimide, thiol, or catechol groups for multistep assembly on inorganic cores.
• Layer-by-layer (LbL) assembly: Electrostatic deposition of polycations (e.g., PAH, PEI) onto negatively charged –COO− surfaces, followed by crosslinking to produce robust shells.
• Surface-initiated polymerization: Anchor RAFT/ATRP initiators via amide linkages to grow polymer brushes from the surface, tailoring colloidal stability and environment responsiveness.
• Solid-support behavior: UCNPs can function as solid-phase nanoscopic supports for catalysts or affinity ligands, enabling luminescent tracing of binding/catalysis events.

Retrosynthetic perspective:

• Treat the nanoparticle as a multivalent carboxylic acid “core” to which ligands, biomolecules, and polymers can be grafted. Crosslinkers like EDC/NHS, DMTMM, or CDI provide orthogonal routes under aqueous or mixed-solvent conditions.

Item-specific parameters (e.g., carboxylate density, accessible surface area, coating identity) that govern coupling efficiency are Not specified; optimize equivalents and contact times empirically.

Target Specificity

This product is a generic, carboxyl-functionalized nanoparticle platform and is not inherently target-specific.

Item-specific data: No antigen/epitope, clone, isotype, or species reactivity is provided for this item.

General guidance (literature):

• Targeting requires post-synthetic conjugation of affinity ligands (e.g., antibodies, peptides, aptamers, small-molecule binders) to the –COOH surface using amide coupling or linker strategies.
• Specificity is determined entirely by the attached ligand’s affinity and valency, as well as surface presentation (ligand density, spacer length, orientation).

Conclusion: Until functionalized with a defined recognition element, these UCNPs have no intrinsic biological target specificity.