excitation and emission plot of SiR

SiR-Maleimide 1mg

CHF350.00

SiR-maleimide is the 2-maleimidoethyl derivative of SiR. It reacts with thiols and allows the preparation of custom SiR-conjugates.

Quantity: 1mg

SKU: SC011 Categories: ,

Description

SiR-maleimide is the 2-maleimidoethyl derivative of the fluorophore silicon rhodamine (SiR). Sir-maleimide reacts with thiols to form covalent conjugates. Small molecules, peptides, oligonucleotides or proteins bearing a free thiol can be conjugated to SiR-maleimide. SiR excitation and emission are compatible with GFP and/or m-cherry fluorescent proteins. It can be imaged with a standard Cy5 filterset.

Properties

λabs 652 nm
εmax 1.0·105 mol-1·cm-1
λfl 674 nm
MW =594.2 g/mol
CF260 = 0.116
CF280 = 0.147

References

1. A near-infrared fluorophore for live-cell super-resolution microscopy of cellular proteins; G. Lukinavičius et al.; Nature Chemistry; 5, 132–139 (2013).

Datasheet

MSDS

Ex/Em spectra (excel format)

1. How many experiments can I do with 50 nmol of SiR-actin?
Depending on the sample volume and the concentration used for labelling, about 50-200 experiments can be done with one vial. 
2. Is SiR-actin stable at room temperature?
Yes, the probe is stable at room temperature for a few days. However, it is recommended to store SiR-actin or solutions thereof at -20°C to maximize shelf-life. 
3. Does SiR-actin stain fixed cells?
Yes, SiR-actin can be used with PFA fixed cells. SiR-actin labels F-actin in PFA fixed cells as efficiently as Phalloidin-derivatives using identical protocol. Sir-actin is not suitable for methanol fixed cells. 
4. Is SiR-actin toxic to the cells?
Yes, above a certain threshold SiR-actin shows some effect on cell proliferation and altered actin dynamics. However, the probe is orders of magnitude less toxic that the parent drug jasplakinolide. In HeLa cells actin dynamics were not altered at concentration below 100 nM. At this concentration, SiR-actin efficiently labels F-actin allowing to record high signal to noise images. 
5. Which organisms and tissues are stained by Sir-actin?
This list is only reporting known working cell lines, tissues or organisms. If a cell line, tissue or organism is not present in the list, it does not mean that it will not be stained by SiR-Probes.

Homo sapiens : U2OS, fibroblasts, HeLa, HUVEC, MCF-10A, HCT-116, A549, erythrocytes.

Mus musculus : C2C12, IA32, skeletal muscle, primary cardiomyocyte, primary oocyte.

Rattus norvegicus : primary hyppocampal neurons, primary cortex neurons NRK.

Cercopithecus aethiops : COS-7.

Mesocricetus auratus : BHK.

Drosophila melanogaster : Notum epithelium, S2.

Didelphis marsupialis : OK-cells.

Help us to complete the list by reporting your positive experiences! 

6. Do SiR-probes work in 3D cell cultures?
Yes, the probes are able to stain cells in a 3D growth environment.
7. What are the correction factors CF260 and CF280 for SiR fluorophore?

CF260 = 0.116

CF280 = 0.147

8. Why are your prices displayed only in CHF (Swiss Francs)?
Our company is based in Switzerland and therefore our list prices are displayed in CHF (Swiss Francs). Upon request, we will provide you with a binding quote (valid 1 month) based on the displayed CHF prices and the actual exchange rate. Please indicate your preferred currency (USD, EUR, CHF) and payment method (bank transfer OR credit card via PayPal).
9. Where can I order my Spirochrome products?
Spirochrome has appointed dedicated distributors for the SiR-probes: SiR-actin, SiR-tubulin, & cytoskeleton-kit. Customers from North America (US and CA) can order them through Cytoskeleton, Inc. and European customers (without Switzerland) can order them through tebu-bio.
The reagents: SiR-COOH, SiR-NHS, & Boc-Lys-jasplakinolide, can be ordered through our website via email or the webshop.

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