5,12-Bis(phenylethynyl)naphthacene 18826-29-4

5,12-Bis(phenylethynyl)naphthacene is a fluorescent dye used in lightsticks. It yields orange light.

CAS number 18826-29-4
PubChem 87816
ChemSpider 79226 Yes
EC number 242-605-4
Jmol-3D images Image 1
Molecular formula C34H20
Molar mass 428.52 g/mol

9,10-Bis(phenylethynyl)anthracene 10075-85-1

9,10-Bis(phenylethynyl)anthracene (BPEA) is an aromatic hydrocarbon with the chemical formula is C30H18. It displays strong fluorescence and is used as a chemiluminescent fluorophore with high quantum efficiency.

It is used in lightsticks as a fluorophor producing ghostly green light. It is also used as a dopant for organic semiconductors in OLEDs.

The emission wavelength can be lowered by substituting the anthracene core by halogens or alkyls. 2-ethyl and 1,2-dimethyl substituted BPEAs are also in use.

CAS number 10075-85-1
PubChem 82338
ChemSpider 74309 Yes
EC number 233-210-8
ChEBI CHEBI:51675 Yes
Jmol-3D images Image 1
Molecular formula C30H18
Molar mass 378.473 g/mol
Appearance Orange needle crystals
Melting point 252 – 258 °C
R-phrases R36/37/38
S-phrases S26 S36 S37/39 S45 S28A
Main hazards Irritant (Xi)

1-Chloro-9,10-bis(phenylethynyl)anthracene 41105-35-5


1-Chloro-9,10-bis(phenylethynyl)anthracene is a fluorescent dye used in lightsticks. It emits yellow-green light, used in 30-minute high-intensityCyalume sticks.

CAS number 41105-35-5
PubChem 170465
ChemSpider 149036 Yes
EC number 255-220-1
Jmol-3D images Image 1
Image 2
Molecular formula C30H17Cl
Molar mass 412.91 g/mol
Appearance Solid
Melting point 199 – 204 °C
R-phrases R36/37/38
S-phrases S26 S36
Main hazards Irritant (Xi)

Ethidium bromide 1239-45-8

Ethidium bromide is an intercalating agent commonly used as a fluorescent tag (nucleic acid stain) in molecular biology laboratories for techniques such as agarose gel electrophoresis. It is commonly abbreviated as “EtBr”, which is also an abbreviation for bromoethane. When exposed to ultraviolet light, it will fluoresce with an orange colour, intensifying almost 20-fold after binding to DNA. Under the name homidium, it has been commonly used since the 1950s in veterinary medicine to treat trypanosomosis in cattle, a disease caused by trypanosomes.[1] The high incidence of antibiotic resistance makes this treatment impractical in some areas, where the related isometamidium chloride is used instead. Ethidium bromide may be a mutagen, carcinogen or teratogen although this depends on the organism and the conditions

Ethidium bromide
CAS number 1239-45-8 Yes
PubChem 14710
ChemSpider 14034 Yes
EC number 214-984-6
KEGG C11161 Yes
ChEBI CHEBI:4883 Yes
RTECS number SF7950000
ATCvet code QP51AX06
Jmol-3D images Image 1


Structure, chemistry, fluorescence

As with most fluorescent compounds, ethidium bromide is aromatic. Its core heterocyclic moiety is generically known as a phenanthridine, an isomer of which is the fluorescent dye acridine.

The reason for ethidium bromide’s intense fluorescence after binding with DNA is probably not due to rigid stabilization of the phenyl moiety, because the phenyl ring has been shown to project outside the intercalated bases. In fact, the phenyl group is found to be almost perpendicular to the plane of the ring system, as it rotates about its single bond to find a position where it will impinge upon the ring system minimally. Instead, the hydrophobic environment found between the base pairs is believed to be responsible. By moving into this hydrophobic environment and away from the solvent, the ethidium cation is forced to shed any water molecules that were associated with it. As water is a highly efficient fluorescent quencher, the removal of these water molecules allows the ethidium to fluoresce.


Ethidium bromide is commonly used to detect nucleic acids in molecular biology laboratories. In the case of DNA this is usually double-stranded DNA from PCRs, restriction digests, etc. Single-stranded RNA can also be detected, since it usually folds back onto itself and thus provides localbase pairing for the dye to intercalate. Detection typically involves a gel containing nucleic acids placed on or under a UV lamp. Since ultravioletlight is harmful to eyes and skin, gels stained with ethidium bromide are usually viewed indirectly using an enclosed camera, with the fluorescentimages recorded as photographs. Where direct viewing is needed, the viewer’s eyes and exposed skin should be protected. In the laboratory the intercalating properties have long been utilized to minimize chromosomal condensation when a culture is exposed to mitotic arresting agents during harvest. The resulting slide preparations permit a higher degree of resolution, and thus more confidence in determining structural integrity of chromosomes upon microscopic analysis.

Ethidium bromide has also been used extensively to reduce mitochondrial DNA copy number in proliferating cells.[2]


There are alternatives to ethidium bromide which are advertised as being less dangerous and having better performance.[3][4] For example, several SYBR-based dyes are used by some researchers and there are other emerging stains such as Novel Juice. SYBR dyes are less mutagenic than EtBr by the Ames test with liver extract.[5] However, SYBR Green I was actually found to be more mutagenic than EthBr to the bacterial cells exposed to UV (which is used to visualize either dye).[6] This may be the case for other “safer” dyes, but whilst mutagenic and toxicity details are available [7] these have not been published in peer reviewed journals. The above article does find that DAPI is a completely nonmutagenic stain. MSDS for SYBR Safe reports a LD50 for rats of >5 g/kg, which is higher than that of EtBr (1.5g/kg), but both are many orders of magnitude higher than the concentrations used in molecular biology. Also, many alternative dyes are suspended in DMSO, which has health implications of its own including increased skin absorption of organic compounds.[5] Despite the performance advantage of using SYBR dyes instead of EtBr for staining purposes, many researchers still prefer EtBr since it is considerably less expensive.

[edit]Health risks

Ethidium bromide is thought to act as a mutagen because it intercalates double stranded DNA (i.e., inserts itself between the strands), deforming the DNA.[8] This could affect DNA biological processes, like DNA replication and transcription. Ethidium bromide has been shown to be mutagenic to bacteria via the Ames test, but only after treatment with liver homogenate, which simulates the metabolic breakdown of the molecule being tested.[9] The lack of detected mutagenicity without liver homogenate indicates that ethidium bromide is not directly mutagenic, but that its metabolites are. The identity of these mutagenic metabolites are unknown. The National Toxicology Program states it is nonmutagenic in rats and mice.[10] These results are supported by a subchronic carcinogenicity study in mice conducted at the university of Düsseldorf where also no mutagenic effects could be detected.[11] Ethidium bromide (Homidium brand) use in animals to treat trypanosome infection suggests that toxicity and mutagenicity are not high. Studies have been conducted in animals to evaluate EtBr as a potential antitumorigenic chemotherapeutic agent.[12] Its chemotherapeutic use is due to its toxicity to mitochondria.[13] A more recent study shows that EtBr acts as a topoisomerase I poison, just like several anticancer drugs used in humans.[14] The above studies do not support the commonly held idea that ethidium bromide is a potent mutagen in humans, but they do indicate that it can be toxic at high concentrations.

Most use of ethidium bromide in the laboratory (0.25–1 microgram/ml) is below the level required for toxicity. The level is high enough that exposure may interfere with replication of mitochondrial DNA in some human cell lines, although the implications of that are not clear. Testing in humans and longer studies in any mammalian system would be required to fully understand the potential risk ethidium bromide poses to lab workers.[15]

Ethidium bromide can be added to YPD media and used as an inhibitor for cell growth.[16]

[edit]Handling and disposal

Ethidium bromide is not regulated as hazardous waste at low concentrations,[17] but is treated as hazardous waste by many organizations. Material should be handled according to the material safety data sheet (MSDS). Wastes should always be treated in accordance with federal, state and local guidelines.

The disposal of laboratory ethidium bromide remains a controversial subject.[18] Ethidium bromide can be degraded chemically, or collected and incinerated. It is common for ethidium bromide waste below a mandated concentration to be disposed of normally (e.g., pouring it down a drain). A common practice is to treat ethidium bromide with sodium hypochlorite (bleach) before disposal.[19] According to Lunn and Sansone, Chemical degradation using bleach yields compounds which are mutagenic by the Ames test. Data are lacking on the mutagenic effects of degradation products. Lunn and Sansone describe more effective methods for degradation.[20] EtBr can be removed from solutions with activated charcoal or amberlite ion exchange resin. Various commercial products are available for this use.

Benzanthrone 82-05-3

Benzanthrone (BZA) is an aromatic hydrocarbon derivate used as a dyestuff intermediate for anthraquinone-based dyes. It has the appearance of a light yellow to brown-green powder with melting point of 170 °C. It is insoluble in water and soluble in alcohol. It is a basic substance withfluorescent and luminescent properties. It can be used for photosensitization, and as a charge transport material. It is also used in pyrotechnicsindustry, mainly as a component of some older formulations of green and yellow colored smokes, often together with Vat Yellow 4; its US military specification is MIL-D-50074D[1].

Its EINECS number is 201-393-3. It is reported to cause itching and burning sensation on exposed skin, together with erythema, dermatitis, and skin pigmentation.

CAS number 82-05-3 Yes
ChemSpider 6442 Yes
Jmol-3D images Image 1
Molecular formula C17H10O
Molar mass 230.26 g mol−1
Melting point 170 °C
Solubility in water Insoluble
S-phrases S24 S25 S26 S28S37 S39S45


CAS No. 8052-41-3
Synonyms: stoddard;APPLICLEAR;WHITE SPIRIT GR;highflashnaphtha;XYLENE SUBSTITUTE;solvents,naphthas;safetysolventnaphtha;6-BROMOHEXYL ACETATE;6-BROMOHEXANOL ACETATE;Stoddard Losungsmittel
CBNumber: CB2104041
Molecular Formula: C8H15BrO2
Formula Weight: 223.109
MOL File: 8052-41-3.mol
mp : 40°C
bp : 149-213°C/760mmHg
density : 0.75 g/mL at 20 °C
refractive index : n20/D 1.417
Fp : 98 °C
storage temp. : Flammables area
Stability:: Flammable. Incompatible with strong oxidizing agents. Store and handle in accord with Petroleum Act.
Hazard Codes : T,Xi,Xn
Risk Statements : 45-65-36/37/38-10
Safety Statements : 53-45-36/37/39-26-46-43-33-16-2
RIDADR : 1263
HazardClass : 3.2
PackingGroup : III

Lucifer yellow 77944-88-8

Lucifer yellow
IUPAC name

6-amino-2-(hydrazinecarbonyl)-1,3-dioxobenzo[de]isoquinoline-5,8-disulfonate de dilithium

PubChem 20835957
ChemSpider 20137740
ChEBI CHEBI:52104 Yes
Jmol-3D images Image 1
  • c1c(cc2c3c1c(c(cc3c(=O)n(c2=O)C(=O)NN)S(=O)(=O)[O-])N)S(=O)(=O)[O-].[Li+].[Li+]




  • InChI=1S/C13H10N4O9S2.2Li/c14-10-5-1-4(27(21,22)23)2-6-9(5)7(3-8(10)28(24,25)26)12(19)17(11(6)18)13(20)16-15;;/h1-3H,14-15H2,(H,16,20)(H,21,22,23)(H,24,25,26);;/q;2*+1/p-2


Molecular formula C13H10Li2N4O9S2
Molar mass 444.25 g mol−1
 Yes (verify) (what is: Yes/?)
Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
Infobox references

Lucifer yellow is a fluorescent dye used in cell biology. The key property of Lucifer yellow is that it can readily visualized in both living and fixed cells using a fluorescence microscope. Lucifer yellow was engineered by Walter W. Stewart at NIH and patented in 1978.[1]

Titanium dioxide 13463-67-7

Product Name: Titanium dioxide
CAS: 13463-67-7
MF: O2Ti
MW: 79.87
EINECS: 215-280-1
Product Categories: Inorganics;Indoles;Inorganic Chemicals;metal oxide
Mol File: 13463-67-7.mol
Titanium dioxide Structure
Titanium dioxide Chemical Properties
mp 1840 °C
bp 2900 °C
density 4.26 g/mL at 25 °C(lit.)
refractive index 2.61
Fp 2500-3000°C
form powder
Water Solubility insoluble
Merck 14,9472
CAS DataBase Reference 13463-67-7(CAS DataBase Reference)
NIST Chemistry Reference Titanium dioxide(13463-67-7)
EPA Substance Registry System Titanium oxide (TiO2)(13463-67-7)
Safety Information
Hazard Codes Xn
Risk Statements 20-36/37/38-20/21/22-38-20/21-10-36/38-22
Safety Statements 26-36-25-2-36/37
WGK Germany -
RTECS XR2275000
HS Code 28230000
Hazardous Substances Data 13463-67-7(Hazardous Substances Data)

Tocilizumab 375823-41-9

Monoclonal antibody

1327-41-9 Structure

1327-41-9 Structure

Type Whole antibody
Source Humanized (from mouse)
Target IL-6 receptor
Clinical data
Trade names Actemra, RoActemra
AHFS/Drugs.com monograph
MedlinePlus a611004
Licence data EMA:Link, US FDA:link
Pregnancy cat. (US)
Legal status ℞ Prescription only
Routes Intravenous infusion
Pharmacokinetic data
Half-life 8–14 days during steady state (dependent on concentration)
CAS number 375823-41-9 
ATC code L04AC07
UNII I031V2H011 Yes
KEGG D02596 Yes
Chemical data
Formula C6428H9976N1720O2018S42 
Mol. mass 145.0 kDa
  (what is this?)  (verify)

Tocilizumab[1] (INN, or atlizumab, developed by Hoffmann–La Roche and Chugai and sold under the trade names Actemra and RoActemra) is an immunosuppressive drug, mainly for the treatment of rheumatoid arthritis (RA) and systemic juvenile idiopathic arthritis, a severe form of RA in children. It is a humanized monoclonal antibody against the interleukin-6 receptor (IL-6R). Interleukin 6 (IL-6) is a cytokine that plays an important role in immune response and is implicated in the pathogenesis of many diseases, such as autoimmune diseases, multiple myeloma and prostate cancer.