Dense silica coated upconverting nanoparticles - Em. Wavelength:545 nm,particle size:35 nm

Cat. No.: D140922

GRADE & PURITY Em. Wavelength:545 nm,particle size:35 nm

Synonyms

Dense silica coated UCNs

Storage

Store at 2-8°C

Shipped In

Wet ice

Panoramica

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

Sinonimi

Dense silica coated UCNs

Specifiche e purezza

Em. Wavelength:545 nm,particle size:35 nm

Condizioni di conservazione di stoccaggio

Store at 2-8°C

Spedito in

Wet ice

Questo prodotto richiede spedizione a catena fredda. I servizi di terra e altri servizi economici non sono disponibili.

Application Protocols

No manufacturer-validated application protocols, test methods, or recommended dilutions are provided for SKU D140922. For research workflows (e.g., imaging, sensing, surface modification), consult the CoA/Spec Sheet for dispersion details and review relevant literature protocols tailored to silica-coated upconverting nanoparticles. Validate conditions at small scale before critical experiments.

Biological Roles

No intrinsic biological role is assigned to dense silica coated upconverting nanoparticles; they are synthetic, inorganic composite materials. The following points summarize their use in biological research contexts (literature; not item-specific and not clinical):

• Optical labels in biochemistry and cell studies:
  • NIR-excited upconversion provides low background in biological matrices and resists photobleaching. Silica shells enable further functionalization with biomolecules via silane chemistry (e.g., APTES → EDC/NHS coupling to proteins or carboxylated ligands).
• Minimization of nonspecific interactions:
  • Dense silica presents a hydrophilic surface; PEG-silane modification is often used to reduce protein adsorption and macrophage uptake in in vitro experiments (literature). Item-specific surface modifiers for SKU D140922 are not specified.
• Sensing and assay development:
  • Time-gated or ratiometric detection platforms exploit long-lived lanthanide emissions to suppress autofluorescence and scattering, improving analytical sensitivity in complex mixtures.
• Enzymology and nucleic acid workflows:
  • Silica surfaces can be tailored to present amines/epoxies for covalent capture of oligonucleotides, peptides, or enzymes, facilitating bioassays under NIR readout.

Important notes:

• No medical, diagnostic, or therapeutic use is intended or implied. For research use only (per product data).
• Biological compatibility, cytotoxicity, and serum stability are system-dependent and must be empirically validated for each application. Review the SDS and perform appropriate in vitro assessments before use with biological samples.

Buffer Applications

This product is a nanoparticle dispersion and not a classical buffering agent. Nevertheless, buffer choice strongly influences colloidal stability and bioassay performance (general, literature):

• Ionic strength and pH:
  • Silica surfaces carry negative charge above pH ~2–3 due to deprotonated silanols; electrostatic stabilization diminishes as ionic strength increases. For electrostatically stabilized dispersions, use low-to-moderate ionic strength buffers (e.g., 1–50 mM) and avoid divalent cations when possible.
  • Typical working pH for silica-coated particles is near neutral (pH 6.5–8.0) to balance stability and biomolecule activity. Strongly basic solutions can etch silica over time.
• Buffer composition:
  • Phosphate (PBS) and HEPES are common. If aggregation is observed in PBS, consider reducing salt or switching to HEPES at similar pH/ionic strength. Adding small amounts of nonionic surfactant (e.g., 0.01–0.05% Tween-20) can improve dispersion (literature). Validate for your assay.
• Filtration and sterilization:
  • Sterile filtration may remove or damage nanoparticles depending on pore size; prefer aseptic handling rather than 0.22 µm filtration for small particles.
• Storage buffers:
  • Include stabilizers compatible with downstream use (e.g., PEG-silanes or protein blockers) when long-term stability is required. Avoid high concentrations of amines if planning EDC/NHS chemistry.

Item-specific dispersant and recommended buffers for SKU D140922 are not provided; consult the CoA/Spec Sheet and run small-scale buffer screens to optimize stability for your workflow.

Green Alternatives

While “green alternatives” are typically framed for solvents or reagents, several sustainability considerations apply to silica-coated UCNPs (general, literature):

• Material choice and composition:
  • Dense silica shells replace hydrophobic organic ligands with an inorganic, glass-like surface, enabling aqueous handling and reducing reliance on volatile organic solvents during use.
  • Compared with cadmium-based quantum dots, UCNPs avoid regulated heavy metals like Cd/Hg. Trade-off: they rely on rare earth elements (REs), which have mining and supply-chain impacts.
• Processing solvents:
  • Favor water/ethanol systems for dispersion and silanization over chlorinated or high-toxicity aprotic solvents when feasible. Optimize silane hydrolysis conditions to minimize excess reagent and solvent waste (literature).
• Energy and light use:
  • NIR excitation can reduce photodamage and improve signal-to-background, potentially lowering required illumination intensity and exposure times, saving energy in imaging workflows.
• Durability and lifecycle:
  • High photostability reduces replacement frequency of probes, potentially lowering overall material consumption. Silica shells also enhance chemical robustness, extending usable lifetime in repeated measurements.

Illustrative comparison (general; not item-specific):

• Silica-coated UCNPs vs CdSe/ZnS QDs
  • Hazard profile: No Cd/Hg (advantage); RE fluoride core still requires responsible disposal.
  • Photostability: Excellent for both; UCNPs resist photobleaching and blinking exceptionally well.
  • Excitation: UCNPs use NIR (lower autofluorescence); QDs require UV/visible (more photodamage risk).

Note: Implement institutional green-chemistry practices—microscale reactions, solvent recycling, and proper nanowaste management—regardless of nanoparticle platform.

Pharmaceutical Uses

No pharmacopeial status, excipient role, or formulation specifications are provided for this product. Dense silica coated upconverting nanoparticles are offered for research use only and are not intended for human or veterinary applications.

General formulation-science context (literature; not item-specific and not an endorsement for clinical use):

• Model nanocarriers and optical tracers:
  • UCNPs can serve as research surrogates to study nanoparticle dispersion stability, protein corona formation, and processing steps in nonclinical settings due to their robust, trackable optical signatures.
• Coating and process development:
  • Silica shells facilitate covalent attachment of polymers (PEG-silanes) or ligands via silane chemistry, enabling studies on steric stabilization and surface energy effects relevant to nanoparticle formulation science.
• Manufacturing considerations:
  • Avoid milling/lyophilization without prior feasibility work, as irreversible aggregation can occur. Gentle mixing and controlled solvent exchange are preferred.

Important: This section provides general background only. SKU D140922 is for research use only, with no medical, diagnostic, or therapeutic claims. Any exploration of pharmaceutical-like processing must remain in preclinical research settings and comply with institutional and regulatory requirements.

Physical Properties

Item-specific physicochemical specifications (size, dispersant, concentration, zeta potential, shell thickness) are not provided for this product. Consult the CoA/Spec Sheet for authoritative values.

• Appearance: Not specified for this item; refer to CoA/Spec Sheet.
• Dispersant/solvent system: Not specified for this item; refer to CoA/Spec Sheet.
• Solid content / concentration: Not specified for this item; refer to CoA/Spec Sheet.
• Hydrodynamic diameter / core size / shell thickness: Not specified for this item; refer to CoA/Spec Sheet.
• Zeta potential / isoelectric point: Not specified for this item; refer to CoA/Spec Sheet.

Literature and general reference values (for context; not item-specific):

• Silica shell: Amorphous SiO2 (density ~2.0–2.2 g/cm³; refractive index nD ~1.45 at 589 nm; literature).
• UCNP optical behavior: Excited typically by NIR (e.g., 808 or 980 nm) with anti-Stokes emission in visible/NIR; narrowband, photostable, minimal blinking (literature).
• Colloidal behavior: Silica surfaces bear –Si–OH that deprotonate above pH ~2–3, giving negative surface charge; zeta potential magnitude decreases with ionic strength (literature).
• Thermal stability: Silica shells remain stable to >400 °C in air; UCNP cores are crystalline lanthanide fluorides stable up to several hundred °C (non-oxidative preferred; literature).
• Solubility: Not a true solute; dispersible as colloids in polar media (water/alcohols) when adequately stabilized; sedimentation depends on size and density (literature).

Note: Do not treat the above as product specifications. Use the item’s CoA/Spec Sheet for measured properties.

Quality and Grades

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

How to interpret quality for silica-coated UCNPs (general guidance for researchers):

• Colloidal quality metrics (literature):
  • Particle size and distribution: Core size (TEM), shell thickness (TEM), and hydrodynamic diameter/PDI (DLS). Lower PDI (<0.2) indicates narrower size distribution in dispersion.
  • Surface chemistry: Presence and density of silanol groups; verification of post-functional groups (–NH2, –SH, –COOH, PEG) by FTIR/XPS/TGA.
  • Optical performance: Upconversion emission spectra, absolute/relative emission intensity under defined excitation (e.g., 980 nm), and photostability over time.
  • Colloidal stability: Zeta potential magnitude and stability tests across pH/ionic strength; accelerated aging at 2–8 °C.
• Silica shell attributes:
  • Dense (nonporous) silica minimizes dye ingress and solvent permeability, reduces surface quenching, and provides a robust glass-like interface for silane coupling (APTES/MPTMS/PEG-silanes). Porosity, if any, should be characterized by nitrogen sorption or dye permeability assays.
• Documentation expectations for high-end materials:
  • CoA/Spec Sheet typically includes synthesis lot, dispersion medium, solid content, TEM images, DLS/PDI, zeta potential, and emission profile. Batch-to-batch reproducibility and stability claims should be supported by QC data.

Note: In the absence of item-specific grade information for SKU D140922, users should verify suitability for their application by reviewing the CoA and, if needed, running incoming QC (DLS, TEM, emission spectra) on receipt.

Reaction and Applications

This product is a nanomaterial used as a photonic probe or building block rather than a classical small-molecule reagent. No item-specific application claims are provided; the following are common research uses for dense silica coated UCNPs (literature):

• Photonics and imaging:
  • Anti-Stokes upconversion under NIR excitation enables deep-light penetration environments and low autofluorescence backgrounds. Emission bands are narrow and photostable.
  • Silica shell suppresses surface quenching and provides a robust, inert interface compatible with further functionalization.
• Sensing platforms:
  • Energy transfer assays (LRET/UCNP-to-dye) exploiting long-lived lanthanide excited states; dense silica helps control donor–acceptor spacing when combined with tailored silane linkers.
  • Ratiometric thermometry and chemical sensing via environment-sensitive dopant transitions or co-loaded reporters in outer layers (literature).
• Security and anti-counterfeiting:
  • Spectrally encoded inks and coatings with multi-color upconversion signatures resistant to photobleaching.
• Catalysis and materials:
  • Light-driven photocatalysis (e.g., NIR-triggered activation of visible-absorbing catalysts placed at/near the particle surface). Silica offers a platform for covalent immobilization via silanes.
• Surface chemistry workflows (general conditions; see also Reaction Conditions tab):
  • Silanization (APTES, MPTMS, epoxy-silanes) in alcohol/water to introduce amine/thiol/epoxy groups.
  • Bioconjugation via EDC/NHS coupling to carboxyls or maleimide–thiol chemistry after shell functionalization.

Note: The above are general research applications and do not constitute specifications or performance claims for SKU D140922. For critical applications, validate emission output, size, and surface chemistry with your own QC.

Reaction Conditions

No item-specific reaction or modification conditions are provided for this product. The following general conditions are commonly used for processing silica-coated UCNPs (literature; validate for your system before scale-up):

• Silanization to introduce functional groups:
  • Solvent: Absolute ethanol or ethanol/water (e.g., 95:5 to 80:20 v/v) to control hydrolysis/condensation; anhydrous conditions can limit premature polymerization.
  • Reagents: Trialkoxysilanes (e.g., APTES 0.1–2% v/v). Catalyst: trace acetic acid or ammonia depending on desired kinetics.
  • Temperature/time: 20–50 °C for 1–12 h with gentle stirring. Thorough washing (ethanol, then water) to remove unreacted silanes and oligomers.
• Bioconjugation (after aminosilanization):
  • EDC/NHS activation of carboxylated ligands in MES buffer (pH ~5.5–6.0), followed by coupling at pH 7–8. Typical reaction times 0.5–4 h at room temperature.
  • Maleimide–thiol coupling in PBS/HEPES at pH 6.5–7.5 for 1–2 h, protected from light.
• Dispersion and deaggregation:
  • Brief probe or bath sonication (seconds–minutes) with cooling to prevent overheating; avoid prolonged high-power sonication that may alter surface chemistry.
• Purification:
  • Centrifugation at modest RCF appropriate to size (optimize empirically), dialysis (if stable), or size-exclusion spin columns for rapid buffer exchange.

Cautions:

• Strong base etches silica; maintain near-neutral conditions post-silanization.
• Fluoride sources (e.g., HF, ammonium fluoride) dissolve both silica and many UCNP cores—avoid during processing.

All conditions above are general literature guidance and are not specifications for SKU D140922.

Safety and Handling

• GHS classification, signal word, pictograms, and H-statements: Not specified for this item; refer to the product SDS for authoritative safety information.
• General nanomaterial precautions (literature/good practice):
  • Avoid generation of aerosols and dry powders. Handle as a wet dispersion when possible. Work in a fume hood or ventilated enclosure when transferring or sonicating.
  • Wear appropriate PPE: lab coat, safety glasses, and chemically resistant gloves. Consider a particulate respirator if aerosolization risk exists (per institutional policy and SDS guidance).
  • Prevent environmental release; collect nanoparticle waste in labeled containers for specialized disposal in accordance with regulations.
• Chemical compatibility (general):
  • Silica shells are stable in neutral aqueous media and many alcohols. Avoid strong bases (can etch silica) and hydrofluoric acid/fluoride sources (aggressive dissolution of both silica and many UCNP cores).
  • Avoid high-ionic-strength solutions if colloidal stability is critical; electrolytes can compress the double layer and induce aggregation.
• Physical hazards:
  • Ultrasonic dispersion can generate heat and aerosol; use cooling and covers. Pressurized or sealed sonication vessels should be avoided.
  • Nanoparticles may adsorb biomolecules; avoid skin contact and ingestion. Do not pipette by mouth.
• First aid (overview; defer to SDS):
  • Inhalation: Move to fresh air; seek medical attention if symptoms develop.
  • Skin/eye contact: Rinse with water for several minutes; remove contaminated clothing; obtain medical advice as needed.
  • Ingestion: Rinse mouth; do not induce vomiting; seek medical attention.

Always consult the SDS for SKU D140922 prior to use.

Solvent Selection

Item-specific dispersant/solvent is not provided; consult the CoA/Spec Sheet to confirm the supplied medium and any stabilizers.

General guidance for silica-coated UCNPs (literature):

• Polarity and miscibility:
  • The silica shell presents hydrophilic –Si–OH groups, favoring dispersion in polar protic solvents (water, lower alcohols). Stability in polar aprotic media (DMF/DMSO) is possible but depends on surface modification and ionic strength.
• Choosing a medium:
  • Aqueous buffers: Use low-to-moderate ionic strength to preserve electrostatic stabilization. Phosphate buffers can work; avoid high salt (>100–150 mM) unless steric stabilization (e.g., PEG-silanes) is present.
  • Alcohols (ethanol/isopropanol): Useful for silanization and for preparing dehydrated dispersions prior to further surface chemistry. Ensure water content matches the protocol.
  • Avoid strong bases (can etch silica) and fluoride-containing solvents/reagents (dissolution hazard for both shell and many UCNP cores).
• Degassing/drying:
  • Not typically required for handling dispersions; however, strictly anhydrous alcohols are preferred for silane coupling reactions to control hydrolysis/condensation kinetics.

Comparison (general, literature):

• Water: Biocompatible handling, easy waste management; ionic strength must be controlled.
• Ethanol: Good for silanization and cleaning; lower dielectric than water, may reduce double-layer stabilization.
• DMSO/DMF: Solubilize some functional silanes and bioconjugation reagents; may change colloidal stability; test at small scale first.

Always verify the supplied medium for SKU D140922 before selecting solvents for dilution or surface modification.

Storage and Reconstitution

• Storage conditions (item-specific): Store at 2–8 °C. Shipped on wet ice (per product data). Keep container tightly closed.
• Stability: Item-specific shelf life and stability data are not provided; refer to CoA/Spec Sheet.

General guidance for nanoparticle dispersions (literature; not item-specific):

• Do not freeze dispersions unless the CoA explicitly supports freeze–thaw stability; freezing can cause irreversible aggregation or phase separation of stabilizers.
• Mix gently before use to re-disperse any settled material. Prefer end-over-end rotation or gentle inversion. Avoid vigorous vortexing that can induce foaming or shear-induced aggregation.
• If needed, apply brief, cooled bath sonication to break soft agglomerates; avoid prolonged high-power probe sonication that can heat and modify surface chemistry.
• Maintain clean, inert containers (borosilicate glass or compatible polymers). Rinse with the same solvent/dispersant to minimize contamination.
• For long-term storage, protect from light if optical properties are critical. Minimize headspace to reduce evaporation and changes in concentration/ionic strength.
• Reconstitution (if supplied as a solid or concentrate): Item-specific instructions are not provided. If concentration adjustment is required, match the dispersant and ionic strength specified in the CoA; add diluent slowly with gentle stirring to avoid local supersaturation and aggregation.

Always consult the product’s CoA and SDS for definitive storage and handling instructions for SKU D140922.

Structure and Identity

Dense silica coated upconverting nanoparticles (UCNPs) are composite nanomaterials consisting of an inorganic upconverting core encapsulated by a conformal, nonporous ("dense") silica (SiO2) shell.

• Item-specific identifiers
  • CAS: Not specified for this item; refer to CoA/Spec Sheet.
  • Molecular formula: Not specified for this item; refer to CoA/Spec Sheet.
  • Molecular weight: Not specified for this item; refer to CoA/Spec Sheet.
  • InChIKey / SMILES: Not applicable to inorganic nanoparticle composites; Not specified for this item; refer to CoA/Spec Sheet.
• Architecture (general, literature)
  • Core: Lanthanide-doped host crystal that converts NIR excitation to visible/NIR emission via sequential photon absorption (typical hosts include NaYF4 with Yb/Er or Yb/Tm dopants; literature).
  • Shell: Amorphous SiO2 layer grown to form a dense, continuous barrier that improves colloidal stability, provides a chemically addressable surface (silanol groups), and suppresses surface quenching (literature).
• Structural features (descriptive, literature)
  • Spherical or spheroidal particulates are common; the silica shell appears as a uniform rim in TEM. The shell presents surface –Si–OH groups amenable to silane coupling (e.g., APTES, MPTMS, PEG-silanes).
  • No organic polymer ligands are necessary for stability once a dense silica shell is present; the surface chemistry is that of silica/glass (literature).
• Identity confirmation (typical characterization, literature)
  • Core crystallinity: XRD (hexagonal vs cubic) and HRTEM.
  • Shell confirmation: TEM (shell thickness), EDS (Si signal), FTIR (Si–O–Si stretching), and TGA (organic content if any).
  • Optical identity: Upconversion emission spectra under NIR excitation (e.g., 808/980 nm) with characteristic narrow f–f transitions (literature).

Note: Specific composition, dopants, particle size, and shell thickness for SKU D140922 are not specified; consult the CoA/Spec Sheet for item-specific identity data.

Synthetic Utility

Although not a small-molecule reagent, dense silica coated UCNPs are versatile synthetic building blocks for functional materials (general, literature):

• Surface functional group chemistry:
  • Native shell: –Si–OH groups enable silane coupling to introduce amines (APTES), thiols (MPTMS), epoxies (GPTMS), carboxyls (via succinic anhydride after amine-silane), or PEG chains (PEG-silanes) for steric stabilization.
  • Orthogonal bioconjugation: After silanization, use EDC/NHS (carboxyl↔amine), maleimide–thiol coupling, azide–alkyne click chemistry (CuAAC or SPAAC) to attach dyes, peptides, oligonucleotides, or polymers.
• Hierarchical assembly:
  • Electrostatic or covalent assembly onto silica, glass, or polymer substrates; layer-by-layer deposition; embedding into sol–gel or polymer matrices to create NIR-responsive composites.
• Photonic integration:
  • Incorporation into resonant cavities, photonic crystals, or waveguides; tailoring refractive index contrast with silica to manage scattering and optical coupling.
• Protection and passivation:
  • Dense silica reduces surface quenching of the UCNP core and provides a stable, low-permeability barrier compared to porous silica or organic ligands, improving emission stability during subsequent wet chemistry.

Item-specific surface state (e.g., as-supplied ligands or functional groups) for SKU D140922 is not specified. Before synthetic modifications, verify the dispersant, solids content, and colloidal stability via CoA and small-scale trials (TEM/DLS/emission) to ensure retention of optical properties through processing.

Target Specificity

Not applicable. This product is a nanoparticle material, not an antibody or affinity reagent. No antigen/epitope, clone, isotype, or species reactivity information is provided for SKU D140922.