Amino-functionalized upconverting nanoparticles - Em. Wavelength:804 nm,particle size:35nm,Coating:dSiO2-NH2

Cat. No.: A140939

GRADE & PURITY Em. Wavelength:804 nm,particle size:35nm,Coating:dSiO2-NH2

Synonyms

Functionalized UCNs

Storage

Room temperature

Shipped In

Normal

Overview

This series of products contains amino functionalized NaYREF4 (RE:Yb, Er, Tm, Gd, Mn, Lu) UCNs with optimal excitation wavelength at 975 nm. The sensitizer is Yb3+, and the activator is Er3+ or Tm3+. The doping concentrations are optimized, leading to strong upconverted emissions at specific wavelengths.The nanoparticles are highly hydrophilic due to the silica coating or PEG coating.The UCNs are of high quantum efficiency and very photostable.
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

Synonyms

Functionalized UCNs

Specifications & Purity

Em. Wavelength:804 nm,particle size:35nm,Coating:dSiO2-NH2

Storage

Room temperature

Shipped In

Normal

Application Protocols

Item-specific, validated protocols are not provided. The following general workflows illustrate common use patterns for amino-functionalized UCNPs. Optimize to your materials and instrumentation.

• Basic dispersion and clarification

  1. Add UCNPs to water or 10 mM phosphate buffer, pH 7.2, to 0.1–1 mg/mL. 2) Brief bath sonication (30–120 s). 3) Optional: clarify by low-retention 0.45–0.8 μm filtration.

• EDC/NHS conjugation to a carboxylated dye or protein (general)

  1. Activate carboxyl partner in 50 mM MES, pH 5.5, with 5 mM EDC + 10 mM NHS for 15–20 min. 2) Exchange UCNPs into pH 7.4 phosphate buffer. 3) Combine activated partner with UCNPs (molar ratio based on accessible –NH2). 4) React 1–2 h at RT with gentle mixing. 5) Quench with 20 mM ethanolamine, 10 min. 6) Purify by centrifugation/redispersion or SEC. 7) Verify conjugation via absorbance/fluorescence and zeta shift.

• Glutaraldehyde crosslinking (general)

  1. Treat UCNPs with 0.05% glutaraldehyde in PBS, 30 min. 2) Wash thoroughly. 3) Add amine-bearing ligand; incubate 1 h. 4) Stabilize with 10 mM NaBH3CN. 5) Purify and characterize.

• Film/ink preparation for anti-counterfeiting

  1. Disperse UCNPs at 1–10 mg/mL in ethanol with 1–5% binder (e.g., PVA). 2) Print/coat onto substrate. 3) Dry at ambient conditions. 4) Excite with NIR to verify patterns.

• Quality checks

  • DLS for hydrodynamic size/PDI, fluorescence spectra under defined power density, and amine quantification (TNBS/fluorescamine) before/after conjugation.

All concentrations/times are general literature guidance; adapt to the specific UCNP lot and ligand chemistry.

Biological Roles

These materials are synthetic inorganic nanoparticles and do not possess intrinsic biological roles. However, in research contexts they are widely used as optical labels and scaffolds due to their NIR-to-visible upconversion.

General/literature insights relevant to biological research (non-clinical):

• Optical benefits: NIR excitation (e.g., ~980 nm; alternative ~808 nm with Nd3+ sensitization) reduces background autofluorescence and light scattering, enabling high signal-to-noise in assays and imaging studies. Emission is photostable and narrow-banded (activator-dependent).
• Conjugation to biomolecules: Surface –NH2 groups can be coupled to proteins, peptides, oligonucleotides, or polysaccharides via standard chemistries (EDC/NHS, glutaraldehyde, or heterobifunctional linkers such as NHS–PEG–maleimide after thiolation). This supports receptor-binding assays, nucleic acid hybridization studies, and UC-FRET constructs.
• Colloidal behavior: Protonated amines confer positive charge at acidic/neutral pH, promoting adsorption to negatively charged biomembranes and proteins; blocking (e.g., with BSA or PEGylation) is often used to minimize nonspecific interactions in assays.
• Photophysics: Upconversion relies on sequential energy transfer between lanthanide ions; emission lifetimes can be microseconds–milliseconds (literature), enabling time-gated detection to suppress short-lived background fluorescence.

Item-specific parameters such as size, coating identity, sterility, and endotoxin levels are not specified for this product. For biological experiments, verify these attributes on the CoA/Spec Sheet and consider conducting in-house cytocompatibility assessments appropriate to your model system. For research use only.

Buffer Applications

While UCNPs are not buffers, appropriate buffer selection is critical for dispersion stability and for surface-coupling reactions involving the –NH2 groups.

• Dispersion buffers (general guidance)

  • Low-ionic-strength phosphate buffer (1–10 mM, pH 6.8–7.4) can maintain colloidal stability; avoid multivalent cations that bridge particles.
  • For positively charged amine-coated particles, inclusion of small amounts of inert electrolytes (10–50 mM NaCl) may screen repulsion and reduce aggregation during centrifugation; empirically optimize.
  • Additives such as 0.01–0.05% nonionic surfactant (Tween-20) can reduce nonspecific adsorption to plastic/glass.

• Coupling buffers

  • EDC/NHS-mediated amide formation: Use MES (25–100 mM, pH 5.0–6.0) for activation of carboxyls; perform coupling in phosphate or HEPES at pH 7.0–7.5. Avoid Tris and other primary amines that quench NHS-esters.
  • Aldehyde coupling: Use phosphate or carbonate buffers at pH 7.4–9.0 for Schiff base formation; follow with reductive amination (NaBH3CN) in the same buffer.

• Electrophoresis/centrifugation notes

  • For purification, size-exclusion on neutral buffers or low-speed differential centrifugation can remove unreacted small molecules without precipitating the nanoparticles. High-speed spins may compact soft aggregates; re-disperse with brief sonication.

Item-specific buffer compatibility, pH windows, and ionic strength limits are not specified for this product; consult the CoA/Spec Sheet and validate conditions at small scale before committing valuable ligands.

Green Alternatives

Sustainability considerations for UCNPs primarily relate to rare-earth sourcing, solvent use during synthesis/processing, and end-of-life handling. While direct “green” substitutes may trade off optical performance, several strategies can reduce footprint.

• Material alternatives (literature comparison)

  • Organic triplet–triplet annihilation upconversion (TTA-UC) systems: metal-free; can be solution-processable. Tradeoffs: oxygen sensitivity, lower stability under continuous excitation, often require deoxygenation.
  • Carbon dots/nitride phosphors: earth-abundant, low-toxicity luminescent materials; typically down-converting with broad emission, lacking true NIR upconversion efficiency of RE-based UCNPs.
  • Manganese-doped or bismuth-based phosphors: partially reduced critical RE content; upconversion performance generally lower than Yb3+/Er3+ UCNPs.

• Process improvements (applicable to UCNP workflows)

  • Use greener solvents for dispersion and surface modification (ethanol/water systems) instead of high-boiling chlorinated or amide solvents when possible.
  • Implement ligand-exchange in aqueous media to avoid extensive use of hexane/oleate phases.
  • Recover and recycle wash solvents; employ low-temperature, energy-efficient drying.

• Design for safer use

  • Prefer robust shells (e.g., silica) to mitigate nanoparticle shedding and facilitate recovery from matrices.
  • Employ PEGylation or zwitterionic coatings to reduce fouling and extend dispersion lifetime, decreasing waste from failed batches.

• End-of-life

  • Collect UCNP-containing wastes for specialized disposal; explore immobilization in cured polymers to minimize environmental release.

Note: The above are general/literature strategies. Item-specific eco-profile and certifications are not specified; refer to CoA/Spec Sheet if available.

Pharmaceutical Uses

No pharmacopeial status or excipient role is provided for this item. This product is labeled for research use only and is not intended for human or veterinary use.

General, non-clinical formulation perspectives for amino-functionalized UCNPs:

• Exploratory delivery/diagnostics research: Aminated surfaces enable conjugation to targeting ligands, polymers (e.g., PEG), or crosslinkers to form prototype constructs for assay development and materials testing. These are research-stage applications and not validated for clinical use.
• Form factor considerations: UCNPs may be provided as dry powders or dispersions. For powders, researchers often formulate in aqueous buffers (pH ~6–8) or alcohols for coatings/inks. For dispersions, excipient selection (e.g., polysorbates, sugars) can modulate stability during storage and lyophilization.
• Regulatory context: If transitioning to regulated studies, documentation would typically include material identity (phase/size/dopants), impurity profile (residual solvents, metals), endotoxin/bioburden (if applicable), and leachables from surface ligands. None of these are specified for this item; refer to CoA/Spec Sheet.

Caution: Avoid implying suitability for therapeutic diagnosis or administration. Perform risk assessments for any contact applications (e.g., device coatings) and ensure comprehensive characterizations of leachables and particle release in the intended environment.

Physical Properties

Item-specific physicochemical specifications are not provided in the Product Data. Refer to CoA/Spec Sheet for quantitative values.

• Appearance: Not specified for this item; refer to CoA/Spec Sheet.
• Particle size (core or hydrodynamic): Not specified for this item; refer to CoA/Spec Sheet.
• Zeta potential: Not specified for this item; refer to CoA/Spec Sheet.
• Concentration/solids content: Not specified for this item; refer to CoA/Spec Sheet.
• Dispersibility: Generally dispersible in water and polar solvents when amines are protonated; actual media tolerance for this item is not specified.

General/literature characteristics for amino-terminated UCNPs (for context only):

• Optical excitation/emission (literature): Typical NIR excitation at ~980 nm (Yb3+ sensitized) with visible emission bands (e.g., Er3+: green ~540 nm, red ~650 nm; Tm3+: blue ~450–480 nm). Alternative 808 nm excitation is possible with Nd3+ sensitization.
• Refractive index (core materials, literature): Rare-earth fluorides often n ≈ 1.45–1.5; oxides higher, ≈1.8–2.0; effective index depends on matrix and coating.
• Surface charge vs pH (literature): Positive at acidic pH due to –NH3+; isoelectric point typically >7 for dense amine coatings.
• Stability notes (literature): Aggregation risk increases with high ionic strength and at pH near the isoelectric point; gentle sonication can aid redispersion.

Values such as melting/boiling point, density, and logP are not meaningful for nanoparticle ensembles; consult CoA for any vendor-specific dispersant or solid content details.

Quality & Grades

• Item-specific grade/purity: Not specified for this item; refer to CoA/Spec Sheet.

Context for UCNP materials quality (general guidance for evaluators):

• Composition verification: Powder X-ray diffraction (phase identification, e.g., hexagonal vs cubic phase for NaREF4; literature) and ICP-OES/ICP-MS for dopant ratios and metal impurities.
• Optical performance metrics: Upconversion emission spectra under defined excitation (e.g., 980 nm), relative quantum yield, and power dependence (log–log slope) to confirm multiphoton behavior. Low background and minimal parasitic downshifting are desirable.
• Surface chemistry confirmation: XPS for nitrogen content, FTIR for –NH2 bands, ninhydrin/TNBS assays or fluorescamine labeling to quantify accessible primary amines (reported as nmol –NH2 per mg particles; not specified for this item).
• Dispersion quality: DLS for hydrodynamic size and PDI; TEM for core size/morphology; zeta potential vs pH for colloidal stability mapping.
• Residual ligands/solvents: TGA and GC–MS of extracts to ensure removal of synthetic organics (e.g., oleate) if water dispersibility is claimed.
• Endotoxin/bioburden (if intended for biological research): LAL test and sterility checks; Not specified for this item unless stated in CoA.

Interpretation of “amine-functionalized” (general): indicates the outer surface presents primary amines competent for carbodiimide coupling or aldehyde condensation. If stabilized by a silane/polymer, that stabilizer can influence zeta potential, colloidal stability, and bioconjugation density; consult the CoA for exact ligand identity.

Reaction & Applications

This product’s surface –NH2 groups enable covalent coupling and assembly in materials and bioanalytical research. Item-specific application validation is not provided; the following reflects general/literature practices.

• Covalent coupling platforms

  • Amide formation with carboxylates via EDC/NHS chemistry (water-compatible). Control pH 5.0–6.5 (MES) for activation, then couple at pH ~7–8.
  • Schiff base formation with aldehydes (glutaraldehyde crosslinking) followed by reductive amination (NaBH3CN) for stable C–N linkages.
  • Activated esters (e.g., NHS-PEG-COOEt) for PEGylation to tune colloidal stability and reduce nonspecific interactions.

• Assembly and composites

  • Layer-by-layer (LbL) deposition alternating amine-terminated UCNPs with polyanions (e.g., PAA) to build films and capsules.
  • Silica encapsulation with TEOS in alcohol/water to create core–shell UCNP@SiO2 while preserving surface amines for further functionalization (when co-condensed silanes are used).
  • Polymer and sol–gel matrices for luminescent coatings, waveguides, and anti-counterfeiting inks; amino groups enhance adhesion to epoxy/PU networks.

• Analytical and imaging research (non-clinical)

  • UCNPs provide NIR-to-visible upconversion with low autofluorescence backgrounds, useful for homogeneous assays, microarrays, and security tagging.
  • Energy transfer constructs (UCNP–acceptor) for UC-FRET studies; amines allow attachment of dyes/acceptors at controlled distances via spacers.

• Practical tips

  • Quantify accessible amines (e.g., TNBS) to stoichiometrically match coupling partners.
  • Maintain gentle mixing; high shear can induce aggregation. Work at concentrations that avoid inner-filter effects in optical readouts.
  • Remove excess reagents by centrifugation/redispersion or size-exclusion where compatible with particle size.

Reaction Conditions

No validated reaction protocols are specified for this item. The following are general/literature conditions commonly used with amino-functionalized UCNPs. Always optimize for your system.

• EDC/NHS amide coupling (to carboxyl ligands/biomolecules)

  • Activation: 25–100 mM MES, pH 5.0–6.0; add EDC (2–10 mM) and NHS (5–25 mM) to carboxyl-bearing partner for 10–30 min at RT.
  • Coupling: Adjust to pH 7.0–7.5 (phosphate/HEPES); mix with aminated UCNPs (e.g., 0.05–2 mg/mL) for 1–4 h at RT with gentle agitation. Quench with ethanolamine or Tris after coupling (if compatible).

• Aldehyde (glutaraldehyde) linkage and reductive amination

  • React aminated UCNPs with 0.01–0.1% glutaraldehyde in phosphate buffer, pH 7.4–8.0, 15–60 min; wash thoroughly. Add aldehyde-bearing partner, then stabilize imines with 5–20 mM NaBH3CN.

• PEGylation with NHS-activated esters

  • Incubate with NHS–PEG–X (molar excess over accessible amines; determine via TNBS) in pH 7.4–8.2 buffer for 1–2 h. Remove excess by centrifugation/SEC.

• Silica encapsulation (Stöber-like, for alcohol-dispersed UCNPs)

  • Disperse in ethanol/water with ammonia; add TEOS (0.1–1% v/v) under stirring at RT for 1–6 h. Incorporate APTES during growth to reintroduce amines to the shell.

• Purification

  • Differential centrifugation (e.g., 3–10k × g, 5–20 min) with low ionic strength buffers; avoid conditions that pellet permanently aggregated material. SEC is gentler for sensitive conjugates.

Reported yields in nanoparticle conjugations are better expressed as coupling density (e.g., nmol ligand/mg UCNP) rather than percent yield; measure by UV–vis or fluorometric tag assays.

Safety & Handling

Safety information specific to this SKU is not provided in the Product Data. Always consult the SDS for authoritative guidance.

• GHS/SDS status

  • Signal word, H-statements, pictograms, and classification: Not specified for this item; refer to SDS.

• General handling recommendations for amino-functionalized UCNPs (good laboratory practice)

  • Avoid inhalation of nanoparticle dust/aerosols; handle powders in a fume hood or ventilated enclosure. Use appropriate respiratory protection if aerosol generation is possible.
  • Wear PPE: lab coat, safety glasses, and nitrile gloves. Change gloves regularly to prevent permeation by surface modifiers.
  • Prevent environmental release; collect nanoparticle waste in labeled containers for hazardous disposal per institutional policy.
  • Avoid contact with strong oxidizers and strong acids/bases that may alter surface functionalization or induce dissolution/etching of fluoride-based cores (literature caution).
  • Minimize prolonged exposure to intense laser/NIR excitation to avoid localized heating of dispersions during optical tests.

• First-aid overview (general)

  • Inhalation: Move to fresh air; seek medical attention if symptoms persist.
  • Skin/eye contact: Rinse with water for ≥15 minutes; remove contaminated clothing; seek medical advice if irritation continues.
  • Ingestion: Rinse mouth; do not induce vomiting; obtain medical attention.

• Fire and reactivity (general)

  • Most inorganic UCNP cores are noncombustible; organic coatings can burn. Use CO2, foam, or dry chemical extinguishers. Thermal decomposition may release fluoride-containing vapors; firefighters should wear SCBA.

Solvent Selection

Amino-functionalized UCNPs are typically dispersible in polar media due to protonatable –NH2/–NH3+ groups; actual compatibility for this item is not specified. Choose dispersion media based on intended chemistry and ionic strength tolerance.

• Polarity and protonation (general/literature)

  • Water (pH 4–8): Protonation to –NH3+ enhances electrostatic stabilization; avoid high salt near the isoelectric point to limit aggregation.
  • Alcohols (ethanol, isopropanol): Useful for inks/coatings; moderate dielectric constant; reduced hydrolysis risk compared to water for some silane coatings.
  • Aprotic polar solvents (DMF, DMSO): Facilitate certain coupling reactions and film casting; test stability as some polymers may swell/destabilize.

• Buffer and additive considerations

  • Avoid primary amine-containing buffers (e.g., Tris) during amide couplings; use MES or phosphate where compatible.
  • Surfactants (e.g., low % Tween-20) can help prevent nonspecific aggregation in aqueous dispersions; verify impact on downstream reactions.

• Practical guidelines

  • Start with low ionic strength media; adjust pH to 6–7 to balance amine protonation and reactivity. Titrate salt upward only as needed for application.
  • Employ brief bath sonication (30–120 s) for redispersion; avoid probe sonication that may fragment particles or strip coatings.
  • Filter through low protein-binding membranes (0.45–0.8 μm) to remove dust/aggregates when optical clarity is important; avoid pore sizes that retain the nanoparticles.

• Comparison snapshot (general)

  • Water: best for bioconjugation and biological assays; may require pH control.
  • Ethanol/IPA: better drying/film formation for printing; faster evaporation.
  • DMF/DMSO: niche solvent processing; ensure compatibility with amine ligands.

Storage & Reconstitution

• Storage conditions (from Product Data)

  • Store at room temperature. Shipped under normal conditions.

• Item-specific stabilizers, preservatives, and shelf life: Not specified for this item; refer to CoA/Spec Sheet.

• General storage guidance for aminated UCNPs

  • Protect from moisture for dry powders; store tightly closed in a clean, inert container. Desiccation and light protection can further preserve surface chemistry and optical properties.
  • For dispersions, avoid microbial contamination; consider sterile filtration if compatible. Store away from strong acids/bases and oxidizers that may alter surface ligands.
  • Minimize repeated freeze–thaw of aqueous dispersions; if freezing is necessary, add cryoprotectants (e.g., glycerol, sugars) after verifying compatibility.

• Reconstitution (general)

  • Powders: Wet with a small volume of ethanol or water, then dilute into the desired medium (e.g., 1–10 mM phosphate, pH 6.8–7.4). Brief bath sonication (30–120 s) promotes dispersion. Adjust pH to maintain partial amine protonation for stability.
  • Concentrated dispersions: Bring to working concentration with matched buffer/solvent. Gently invert or roll; avoid vigorous vortexing that may induce aggregation.

• Stability monitoring

  • Inspect for visible aggregates or precipitation; check DLS and emission intensity periodically. If aggregation occurs, low-ionic-strength buffer and brief sonication often restore dispersion.

• Research use note

  • For research use only. Not for human or veterinary applications.

Structure & Identity

Amino-functionalized upconverting nanoparticles (UCNPs) are inorganic nanocrystals bearing primary amine (–NH2) groups on their surface for downstream conjugation and assembly.

• Item-specific identifiers

  • Molecular Formula: Not specified for this item; refer to CoA/Spec Sheet.
  • Molecular Weight: Not specified for this item; refer to CoA/Spec Sheet.
  • CAS: Not specified for this item; refer to CoA/Spec Sheet.
  • InChIKey: Not specified for this item; refer to CoA/Spec Sheet.
  • SMILES: Not applicable to nanoparticle ensembles; Not specified for this item; refer to CoA/Spec Sheet.

• Structural features (general/literature description)

  • Core: Typically rare-earth fluoride or oxide upconverters (e.g., NaREF4 with Yb3+ sensitizer and Er3+/Tm3+/Ho3+ activator; literature), which convert NIR excitation to visible emission by multiphoton processes.
  • Shelling: Often inert shells (e.g., NaYF4) to improve quantum yield (literature); presence not specified for this product.
  • Surface chemistry: Primary amines presented via silane (e.g., APTES), polymer capping (e.g., PEI), or ligand-exchange routes (literature). Exact ligand for this item: Not specified.
  • Morphology: UCNPs are commonly spherical or hexagonal prisms; typical diameters range from 10–100 nm depending on synthesis (literature). Size/morphology for this item: Not specified.

• 2D verbal depiction

  • Consider the particle as an inorganic crystalline core (ionic lattice) encapsulated in an organic/organosilica corona that terminates in –NH2 groups. The amines are protonatable, conferring pH-dependent charge for dispersion and providing nucleophilic sites for coupling to carboxyls (amide formation) or aldehydes (Schiff base), enabling bioconjugation and materials assembly.

Synthetic Utility

As functional nanobuilding blocks, amino-functionalized UCNPs serve as reactive substrates in materials synthesis and surface-engineering workflows rather than as molecular reagents.

• Surface-reactive handle

  • Primary amines enable straightforward coupling to carboxyl-, aldehyde-, and activated-ester-bearing molecules (polymers, dyes, biomolecules), creating hierarchical structures with embedded upconversion centers.
  • Heterobifunctional linkers (e.g., NHS–PEG–maleimide) bridge UCNP surfaces to thiolated ligands, offering spatial separation to mitigate quenching and steric hindrance.

• Platform for core–shell architectures

  • Subsequent growth of silica, titania, or polymer shells can be initiated while retaining or regenerating amines, enabling multilayer constructs, charge inversion, and LbL assembly.

• Retrosynthetic thinking (materials perspective)

  • Target film/coating/ink with defined emission: decompose the design into UCNP core properties (dopant set, shell), surface ligand with –NH2 for coupling, and matrix chemistry (epoxy/PU/acrylate) for integration.
  • Target biosensing probe: specify recognition element (e.g., carboxylated antibody fragment or aptamer), spacer length (PEGn) to control FRET distance, and passivation layer to suppress nonspecific binding.

• Integration into devices

  • Patterning via inkjet/pen writing in alcohol-based vehicles; crosslink amines with multifunctional epoxies for robust adhesion.
  • Embedding in sol–gel-derived silica or ORMOSILs to form photonic coatings with environmental resilience.

Item-specific reactivity metrics (amine density, ligand identity) are not specified; determine empirical coupling efficiencies via colorimetric amine assays and test reactions at small scale.

Target Specificity

Not applicable. This product is not an antibody, oligonucleotide, or affinity reagent with inherent biological target specificity. Any specificity arises from ligands that users conjugate to the surface –NH2 groups (e.g., antibodies, peptides, aptamers), which are not provided or specified for this item.