Invitrogen™ Qtracker™ 655 Vascular Labels

Catalog No.	Quantity
Q21021MP	200 μL

Catalog No. Q21021MP Supplier Invitrogen™ Supplier No. Q21021MP

Description

Includes

200μL Qtracker non-targeted quantum dots (2μM solution in 50mm borate buffer, pH 8.3).

Non-targeted quantum dots are designed to be injected into tail vein of mice for study of vascular structure using small animal in vivo imaging (SAIVI) techniques

• These nanocrystals exhibit intense fluorescence with red-shifted emission for increased tissue penetration, and have a PEG surface coating specially developed to minimize nonspecific interactions and reduce immune response by the tissue
• Because PEG surface coating does not contain reactive functional groups, dots are retained in circulation longer and can be imaged for up to 3 hours with single injection or for longer periods of time with additional injections
• Qtracker 655 label has Ex/Em (405-615/655)nm

Cell Analysis, Cellular Imaging, In Vivo Imaging

Order Info

Shipping Condition: Room temperature

Specifications

• Concentration: 2 μM
• Content And Storage: Contains 200 μl Qtracker™ non-targeted quantum dots (2 μM solution in 50 mM borate buffer, pH 8.3). Store at 2–6°C. Do not freeze. Stable for at least 6 months.
• Dye Type: Qdot Nanocrystals
• Quantity: 200 μL
• Product Line: QTRACKER, Qdot
• Reagent Type: Vascular Imaging Reagents
• Shipping Condition: Room Temperature
• Technique: In Vivo Imaging
• Product Type: Vascular Label

Frequently Asked Questions (FAQs)

When I label with Qtracker cell labeling reagents, I get a punctate label pattern. How do I make it more uniform?

Qtracker cell labeling reagents are taken up by the cell through endocytosis and sequestered in endosomes. This gives the label a punctate or vesicular appearance. This is normal. There is nothing that can be done to make it appear uniform throughout the cytoplasm.

How long after injection should I start imaging my mouse?

The imaging time course varies with the nature of the injected agent. Vascular tracers are visible in the blood vessels immediately after injection and may be imaged for several hours. Conjugated whole IgG antibodies reach their targets within a few hours of injection and may be imaged for several days.

What happens to unconjugated dye in the mouse after small animal in vivo imaging?

The dye will be eliminated via the bladder. The bladder signal is detectable within ~3 minutes of IV injection of the dye and clearance with ~30 minutes.

What amount of Qtracker non-targeted reagent should I inject to image vasculature?

A recommended starting dosage is 25-50 µL of Qtracker reagent diluted to the desired injection volume with PBS or normal saline. Qtracker reagent should be diluted immediately prior to injection. DO NOT STORE DILUTED. You will need to determine the optimal dosage for your experimental models.

I want to track my cells with a nucleic acid stain, like DAPI or Hoechst dye. Do you recommend this?

This is not recommended. When these stains bind to DNA and RNA, they may affect the normal function of the nucleic acids, disrupting transcription, as well as replication. Other reagents, such as CellTracker dyes or Qtracker reagents are more optimized for tracking without disrupting normal activity. If a nuclear label is still desired, though, and the cells are mammalian and non-hematopoietic, CellLight nuclear reagents can transiently transfect cells to express GFP or RFP on a nuclear-expressing protein for up to several days without affecting function.

I want to track my cells over time, and you have a lot of options to choose from. How do I pick the right one?

Please see this Web link (http://www.thermofisher.com/us/en/home/life-science/cell-analysis/cell-tracing-tracking-and-morphology/cell-tracking.html) to help you choose the right option for your application. Start by planning how long you want to track your cells, then consider the mechanism of binding. Calcein dyes are very uniform in label and are good for short-term cell migration, but may be rapidly effluxed from some cell types. Lipophilic cyanine dyes, such as DiI, DiO, and similar dyes label cell membranes, don’t disrupt function, and can last longer, but have the potential to cross to other cells if membranes fuse. They are also lost upon permeabilization. CellTracker dyes are better for longer-term labeling, as they possess a mildly reactive chloromethyl moiety that allows covalent binding to cellular components. CFDA SE also covalently binds to cellular components. With all the reagents, their retention within cells is dependent upon the rate of cell division and the inherent properties of the cell (active efflux, membrane and protein turnover rates, etc.) and reagents that allow for covalent attachment exhibit longer retention than those that do not.

The longest-lasting and brightest options are the Qtracker reagents, which are taken up through endocytosis. These are so bright individual quantum dots can be detected, and are also robust enough to survive not only fixation and permeabilization, but even the heat and solvents used in paraffin processing.

Safety and Handling

WARNING: Cancer - www.P65Warnings.ca.gov

For Research Use Only. Not for use in diagnostic procedures.