Dense silica coated upconverting nanoparticles - Em. Wavelength:804 nm,particle size:35 nm

Cat. No.: D140924

GRADE & PURITY Em. Wavelength:804 nm,particle size:35 nm

Synonyms

Dense silica coated UCNs

Storage

Store at 2-8°C

Shipped In

Wet ice

Übersicht

This series of products contains dense silica coated 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.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, photodynamic therapy and photoactivation of anti-cancer drugs and biomolecules

Specifications

Synonyme

Dense silica coated UCNs

Spezifikationen & Reinheit

Em. Wavelength:804 nm,particle size:35 nm

Storage

Store at 2-8°C

Verschickt in

Wet ice

Dieses Produkt erfordert Kühlkettenversand. Grundversand und andere Economy-Optionen sind nicht verfügbar.

Application Protocols

No supplier-validated application protocols are provided for this specific item. The following general, literature-informed workflows can serve as starting points. Optimize for your formulation and instrumentation.

• Redispersion and optical measurement (research use only)
  1. Equilibrate vial to room temperature. 2) Gently invert to resuspend; brief bath sonication (1–5 min) if needed. 3) Dilute into low-ionic-strength water or buffer. 4) Optionally filter (0.45–0.22 µm) if particle size allows. 5) Excite with NIR laser diode (e.g., 808 or 980 nm, literature) and record emission spectrum.
• Aminosilanization of silica shell (APTES, general)
  1. Wash particles into absolute ethanol. 2) Add 0.5–2% v/v APTES with ~0.1–0.5% water. 3) Stir 1–3 h at RT. 4) Wash with ethanol, then water. 5) Cure 60–90°C for 1–2 h. 6) Verify surface amines (ninhydrin, fluorescamine, or XPS).
• NHS-ester dye/protein coupling (after aminosilanization)
  1. Disperse in HEPES or bicarbonate buffer, pH 7.8–8.5. 2) Add NHS-activated dye/protein; react 30–120 min. 3) Quench with ethanolamine. 4) Purify by centrifugation/washing. 5) Characterize via absorbance/PL and SDS-PAGE (for proteins bound to large NPs, analyze supernatants).
• Printing/coating (inks)
  1. Prepare water/ethanol blend with suitable viscosity modifiers. 2) Add dispersion with gentle stirring. 3) Filter (if feasible). 4) Deposit by inkjet/screen/slot-die. 5) Dry at ambient–60°C; avoid temperatures that alter matrix or induce aggregation.
• Item-specific parameters (concentrations, solids content)
  • Not specified for this item; refer to CoA/Spec Sheet.

Biological Roles

This product is an inorganic nanomaterial and does not possess intrinsic biological roles such as metabolic functions or receptor interactions.

• Research-use contexts (literature/general; no clinical claims)
  • As photonic labels in immunoassays or nucleic acid assays under NIR excitation, offering low autofluorescence backgrounds.
  • As calibration standards for optical instrumentation (e.g., NIR-excited confocal/FLIM setups) due to stable, characteristic emission lines of lanthanide activators when present.
  • As carriers for surface-presented ligands after silane-mediated functionalization (e.g., peptides, antibodies) enabling specific binding studies in vitro. Any biological interactions derive from grafted ligands, not from the silica-coated UCNP core itself.
• Biocompatibility considerations
  • Dense silica shells generally improve aqueous compatibility and can reduce direct exposure of cells to the inorganic core; however, cytocompatibility is formulation- and dose-dependent and must be empirically verified for each application (research use only).
• Item-specific biological attributes (endotoxin, sterile status, ligand content)
  • Not specified for this item; refer to CoA/Spec Sheet. Users should confirm sterility and endotoxin levels if planning cell-associated experiments.

Buffer Applications

As particulate photonic labels rather than buffering agents, these nanoparticles are not used to set or maintain pH. However, the choice of buffer impacts colloidal stability and optical measurements.

• Item-specific dispersion/buffer guidance: Not specified for this item; refer to CoA/Spec Sheet.
• General/literature guidance for silica-coated nanoparticles
  • Compatible buffers: HEPES, Tris, and borate at low–moderate ionic strength often support good dispersion for silica-shelled particles.
  • Ionic strength: keep as low as practical for optical work to minimize aggregation and scattering; add salt incrementally if needed for biological function.
  • pH window: neutral to mildly basic (pH ~6.5–9) commonly yields negatively charged silica surfaces and improved stability; very low pH increases silanol protonation, potentially reducing electrostatic repulsion.
  • Additives: nonionic surfactants (e.g., Tween 20 at low ppm levels) can help prevent nonspecific adsorption to plastics/glass; verify that additives do not quench or reabsorb emission.
  • Filtration: if particle size allows, gentle filtration (0.45–0.22 µm) can remove dust/aggregates before measurements.
• Cautions
  • Avoid high concentrations of multivalent cations and polycations (e.g., PEI) unless intentional bridging/flocculation is desired.
  • If the core contains fluoride-based materials (common in UCNPs, literature), avoid fluoride-rich or strongly basic media that might etch the shell/core.

Green Alternatives

While nanoparticles are not “green solvents/reagents,” thoughtful selection and processing can reduce environmental footprint.

• Comparative considerations (literature/general)
  • Versus organic dyes: UCNPs offer exceptional photostability and narrow-line emissions, reducing the need for frequent dye replacement; however, they involve inorganic synthesis and rare-earth sourcing. Dense silica shells improve reusability and chemical robustness.
  • Versus quantum dots (Cd/Pb-based): UCNPs avoid cadmium/lead; dense silica encapsulation further mitigates ion release risk. Tradeoff: lower absorption cross-section may demand higher excitation power.
  • Processing media: choose water/ethanol over chlorinated or high-VOC solvents when possible; perform silanization in ethanol/IPA with controlled water rather than toluene when compatible.
• Waste and lifecycle suggestions
  • Recycle/repurpose: incorporate used dispersions into cured polymer matrices for calibration standards rather than disposal when feasible.
  • Minimize nanoparticle release: favor immobilization (silica sol–gel, crosslinked polymers) in applications to reduce environmental dispersion.
• Quick comparison table (general)
  • Option: UCNP@dense-SiO2 vs organic dyes
    • Pros: photostable, reusable, low photobleaching
    • Cons: higher excitation irradiance, inorganic waste streams
  • Option: UCNP@dense-SiO2 vs CdSe QDs
    • Pros: Cd/Pb-free, narrow f–f emissions, robust shell
    • Cons: typically lower brightness per particle at low powers

Pharmaceutical Uses

This product is provided strictly for research use only and is not intended for human or animal therapeutic, diagnostic, or clinical applications.

• Formulation/excipient status
  • No pharmacopeial monograph or excipient designation is provided for this item. Any use in pharmaceutical development would require independent qualification and toxicological assessment.
• Potential roles in preclinical formulation research (literature/general; no clinical claims)
  • Model particulate tracer for studying formulation rheology or deposition (e.g., inks, coatings) using NIR-excited readouts.
  • Optical barcodes for tracking of dosage forms in manufacturing environments.
• Regulatory and CMC considerations (general)
  • For any regulated work, control of particle size distribution, surface chemistry, residual solvents, and elemental impurities must be established; dense silica shells may aid in controlling surface composition, but full characterization is required.
• Item-specific pharmaceutical attributes (sterility/endotoxin, residual solvent, elemental profile)
  • Not specified for this item; refer to CoA/Spec Sheet.

Physical Properties

• Item-specific physicochemical data
  • Particle size (core/shell, hydrodynamic): Not specified for this item; refer to CoA/Spec Sheet.
  • Dispersed state/solvent: Not specified for this item; refer to CoA/Spec Sheet.
  • Zeta potential: Not specified for this item; refer to CoA/Spec Sheet.
  • Density, MP/BP, refractive index (bulk): Not applicable/Not specified for this item; refer to CoA/Spec Sheet.
• General/literature characteristics of dense silica coated UCNPs
  • Optical behavior: exhibit anti-Stokes upconversion; common NIR excitations at ~980 nm or ~808 nm yield visible or NIR emissions (e.g., green from Er3+, blue from Tm3+, red from Er3+/Ho3+) depending on dopants (literature).
  • Surface chemistry: silica shells present silanols; isoelectric point typically in the pH ~2–4 range for amorphous silica, yielding negative zeta potentials above neutral pH (literature, general for silica surfaces).
  • Colloidal stability: favored in low–to–moderate ionic strength aqueous media; high salt or extremes of pH can promote aggregation (literature).
  • Thermal/photostability: UCNP cores are photostable compared with organic dyes; silica shells enhance chemical robustness and reduce quenching by solvents/adsorbates (literature).
  • Dispersibility: dense silica confers hydrophilicity; particles generally redisperse in water, common buffers, and polar protic solvents with mild sonication (literature). Specific solvent compatibility for this item: Not specified; refer to CoA/Spec Sheet.

Quality and Grades

• Item-specific grade/purity: Not specified for this item; refer to CoA/Spec Sheet.
• What “dense silica coated” implies for quality
  • A dense (low-porosity) silica shell provides a robust physical barrier that helps:
    • Minimize surface quenching and solvent access to the luminescent core.
    • Improve colloidal stability across a wider ionic strength/pH window versus ligand-only stabilized UCNPs.
    • Provide a uniform, hydroxylated surface amenable to well-controlled silane coupling (APTES, AEAPTMS, MPTMS) for downstream bioconjugation or polymer grafting.
  • Compared with porous silica shells, dense silica typically exhibits lower dye uptake and slower mass transport, advantageous where spectral purity and leach resistance are critical (e.g., encoding, anti-counterfeiting labels) (general/literature).
• Recommended documentation and QC checks (user guidance)
  • Request CoA for: core composition/dopants, particle size and dispersity (TEM/DLS), silica shell thickness, solids content, dispersion medium, zeta potential, optical excitation/emission spectra, and endotoxin/bioburden status if relevant to your workflow.
  • Verify batch-to-batch consistency via: absorbance/PL spectra, DLS hydrodynamic size, and sedimentation behavior. Confirm surface functionality post-silanization by FTIR/XPS or dye-binding assays as appropriate.

Reaction and Applications

• Primary application domains (research/literature; no clinical claims)
  • Photon upconversion: anti-Stokes emission for encoded security inks, micro/nano barcodes, optical power conversion, and background-free assays.
  • Bioassay labels and imaging probes (research use only): NIR excitation reduces autofluorescence and photodamage relative to UV/visible excitation; dense silica enhances chemical robustness and provides a handle for bioconjugation.
  • Energy/photonic devices: waveguides, solid-state displays, and luminescent solar concentrators using UCNP-doped matrices.
• Practical handling and processing tips
  • Dispersion: mild bath sonication (1–10 minutes, literature) often restores colloidal stability; avoid probe-tip overheating. Filter large aggregates if optical clarity is critical.
  • Surface chemistry: utilize silane coupling on the silica shell to introduce amine (APTES), epoxy (GPTMS), thiol (MPTMS), or PEG chains. Control water, solvent, and curing conditions to achieve monolayer, non-aggregating coatings.
  • Bioconjugation workflow (research use only): after aminosilanization, use NHS esters for dye/protein attachment or glutaraldehyde/EDC-compatible strategies depending on counter-functional groups.
  • Matrix incorporation: blend with sol–gel silica, PMMA, or epoxies; match refractive index and curing temperature to minimize scattering and quenching.
• Notes specific to this item
  • Core composition/emission profile, particle size, and dispersion medium: Not specified for this item; refer to CoA/Spec Sheet before designing optical filters, excitation sources, or conjugation chemistries.

Reaction Conditions

Because this product serves as a nanomaterial rather than a reactant in stoichiometric organic reactions, “reaction conditions” here refer to surface modification and processing parameters (literature/general guidance; adjust to your system).

• Silanization of the dense silica shell
  • Solvent: absolute ethanol or isopropanol; alternatives include anhydrous toluene for some organosilanes.
  • Water content: catalytic amounts (0.1–1% v/v) promote hydrolysis–condensation; too much water leads to polymerized siloxane particulates.
  • Silane loading: 0.5–5% v/v typical for APTES/GPTMS; optimize to avoid interparticle crosslinking.
  • Temperature/time: room temperature to 70°C for 0.5–12 h; brief curing at 60–110°C can strengthen the siloxane network.
  • pH: mildly acidic or neutral favors controlled hydrolysis; strong base accelerates condensation and can roughen silica.
• Bioconjugation after aminosilanization (research use only)
  • NHS ester coupling: pH 7.4–8.5 in phosphate-free buffers (e.g., HEPES) for 0.5–2 h; quench with ethanolamine.
  • Click chemistry: CuAAC via Cu(I) catalysts in aqueous/tert-butanol media; or copper-free SPAAC in purely aqueous buffers.
• Dispersion processing
  • Sonication: bath sonication 1–10 min to redisperse; avoid overheating. Probe sonication briefly with pulsing if necessary.
  • Filtration/centrifugation: low-speed spin to remove large aggregates; membrane filtration if particle size permits.
• Item-specific optimal conditions
  • Not specified for this item; refer to CoA/Spec Sheet and validate empirically on a small scale.

Safety and Handling

• GHS classification and pictograms: Not specified for this item; refer to SDS for authoritative safety information.
• General laboratory precautions (materials/nanomaterials best practice)
  • Handle as a research-use material only; avoid generating aerosols or dust. For liquid dispersions, keep sealed to prevent drying. Use in a fume hood or well-ventilated area when preparing or sonicating dispersions.
  • Personal protective equipment: safety glasses, lab coat, and appropriate chemically resistant gloves. Consider respiratory protection if dry powders are handled or if nebulization is possible; consult SDS and institutional EHS guidance.
  • Incompatibilities: strong bases can etch silica; hydrofluoric acid and fluoride sources can attack both silica shells and many UCNP cores. Avoid strong oxidizers and conditions that promote ligand desorption/aggregation.
  • First aid (overview; defer to SDS): eye/skin contact—rinse with water for at least 15 minutes; inhalation—move to fresh air; ingestion—rinse mouth and seek medical evaluation. Provide SDS to healthcare professionals.
  • Spill/cleanup: for liquids, contain with absorbent; for powders, avoid dry sweeping—use dampened disposable wipes or HEPA-filtered vacuum. Dispose according to local regulations.
  • Environmental note: prevent release to drains; collect nanoparticle waste separately per institutional nanomaterial waste procedures.

Solvent Selection

This product is a nanodispersion/particulate solid rather than a molecular solute; solvent choice governs colloidal stability, surface charge, and optical performance rather than thermodynamic solubility.

• Item-specific solvent/dispersant: Not specified for this item; refer to CoA/Spec Sheet.
• General guidance for dense silica coated UCNPs (literature/general)
  • Preferred media: deionized water and common biological buffers (e.g., HEPES, Tris) at low–moderate ionic strength. Alcohols (ethanol, isopropanol) can be used for processing and silanization steps.
  • Avoid/Use with caution: high ionic strength (>0.5–1 M salts), multivalent cations (can screen charges and induce aggregation), extreme pH (<2 or >11) that can condense/deprotonate silanols excessively or etch silica.
  • Dielectric/polarity: silica surfaces are hydrophilic; protic, polar media typically yield better dispersion than nonpolar solvents unless surface is further modified with organosilanes.
• Practical selection scenarios
  • Optical measurements: water or buffer at low ionic strength to minimize scattering from aggregates; filter (0.22–0.45 µm) if compatible.
  • Surface functionalization: anhydrous alcohols (EtOH/IPA) or aqueous–alcohol mixtures for silane coupling; strictly control water content for monolayer silanization.
  • Printing/coatings: alcohols or water–alcohol blends for rapid drying; add compatible nonionic surfactants if needed to improve wetting on substrates.
• Comparison (general)
  • Silica-coated vs ligand-only UCNPs: silica allows aqueous processing without amphiphiles; ligand-only systems often require organic solvents (e.g., hexane/toluene).

Storage and Reconstitution

• Storage conditions (item-specific from Product Data)
  • Store at 2–8°C. Shipped on wet ice. Keep container tightly closed to prevent evaporation and crust formation.
• Stability guidance
  • Avoid freezing unless the formulation is validated for freeze–thaw; ice crystallization and concentration gradients can induce aggregation. Protect from microbial contamination; if long-term storage is required in aqueous media, consider sterile filtration and addition of a compatible preservative (user validated).
• Reconstitution/redispersion (general)
  • If received as a dispersion: equilibrate to room temperature, gently invert to homogenize, and apply brief bath sonication (1–5 min) to redisperse. If received as a dried solid, add an appropriate dispersant (water or alcohol per your application), then sonicate gently; avoid local overheating.
  • Use low-ionic-strength media for initial reconstitution; adjust pH and salt gradually while monitoring DLS or turbidity to avoid aggregation.
• Container/material compatibility
  • Use low-protein-binding plastics or borosilicate glass. Pre-wet surfaces to reduce adsorption. Store upright to minimize leakage and headspace changes.
• Shelf-life and specifications
  • Expiry, solids content, and exact dispersant composition: Not specified for this item; refer to CoA/Spec Sheet.
• Research use note
  • For research use only. Not for human or animal therapeutic or diagnostic use.

Structure and Identity

Dense silica coated upconverting nanoparticles (UCNPs) are core–shell nanomaterials in which an inorganic, photon upconverting core is encapsulated within a dense, conformal silica layer.

• Item-specific identifiers
  • CAS: Not specified for this item; refer to CoA/Spec Sheet.
  • InChIKey: Not applicable to heterogeneous nanoparticles.
  • SMILES: Not applicable to heterogeneous nanoparticles.
  • Molecular formula: Not specified for this item; refer to CoA/Spec Sheet.
  • Molecular weight: Not specified for this item; refer to CoA/Spec Sheet.
• Structural features (general/literature)
  • Core–shell architecture: luminescent UCNP core surrounded by a dense amorphous SiO2 shell (literature).
  • The silica shell provides a hydroxylated surface (≡Si–OH) suitable for silane coupling chemistries (e.g., APTES, MPTMS) (literature).
  • UCNP cores are commonly rare-earth–doped fluorides (e.g., NaYF4:Yb/Er, NaYF4:Yb/Tm) enabling anti-Stokes upconversion under NIR excitation (808–980 nm) (literature). Specific dopant system for this item: Not specified for this item; refer to CoA/Spec Sheet.
• 2D/descriptor-style description
  • In schematic, the particle shows a luminescent inorganic core (spherical/hexagonal prism, literature-general) encapsulated by a uniform silica layer; the outer surface terminates in silanol groups conferring hydrophilicity and enabling further functionalization.
• Distinguishing attribute
  • “Dense silica” indicates a compact, non-porous or low-porosity silica layer designed to suppress dye leaching/ion exchange and to improve chemical/colloidal robustness compared with porous silica shells (general).

Synthetic Utility

Although not a molecular building block, dense silica coated UCNPs are valuable as functional nanobuilding units in materials synthesis and device fabrication.

• Functional features enabling synthesis/fabrication
  • Silica shell chemistry: surface silanols allow covalent grafting of organosilanes bearing amine, epoxy, thiol, azide, alkyne, or PEG groups; enables click chemistry (CuAAC, SPAAC) or NHS-ester coupling after appropriate priming.
  • Robust core–shell: dense silica acts as a diffusion barrier, allowing processing in a range of media and under modest thermal curing without degrading optical properties (literature/general).
• Typical transformations/workflows
  • Monolayer silanization (APTES, GPTMS) in dry ethanol or toluene with controlled water, followed by curing (60–110°C, literature-general) to crosslink the siloxane network.
  • Polymer grafting-from or grafting-to approaches: initiate surface-initiated polymerizations (e.g., ATRP, RAFT) after installing suitable initiator silanes to create brushes that tune colloidal stability and matrix compatibility.
  • Inorganic integration: embed UCNP@SiO2 in sol–gel silica, silica aerogels, or hybrid ORMOSIL networks to build photonic composites.
• Advantages of silica coating for downstream chemistry
  • Minimizes ligand desorption issues typical of hydrophobic UCNPs.
  • Offers predictable, reproducible silane coupling compared with native inorganic surfaces.
• Item-specific reactivity/functional group content
  • Not specified for this item; refer to CoA/Spec Sheet.

Target Specificity

Not applicable. This product is a generic nanomaterial and is not an affinity reagent or biologic with defined target specificity.

• Item-specific antigen/epitope/clone/isotype: Not applicable.
• If functionalized by the end user (research use only): any target specificity will arise from ligands you covalently attach to the silica surface (e.g., antibodies, peptides, aptamers). Validate binding independently via appropriate controls.