Fluorescent dye
Indocyanine Green does not have a specific pharmacological target in the traditional sense, as it is a diagnostic imaging agent rather than a therapeutic drug. Its utility is based on its optical properties, specifically its near-infrared fluorescence, and its pharmacokinetic behavior. It binds to plasma proteins after intravenous injection and is rapidly cleared by the liver. Its distribution and clearance are used to assess hepatic function and blood flow.

The expression of BAX was dramatically elevated in HGF cells by indocyanine green (Foxgreen)-photodynamic therapy (ICG-PDT) at a concentration of 1000 μg/mL. On the other hand, BCL-2 gene Impact expression was not significantly affected by laser irradiation or ICG.
ICG is used as a diagnostic tool rather than a therapeutic agent, so its "activity" is related to its optical properties. After intravenous injection, it binds to plasma proteins and remains intravascular. It fluoresces when excited by NIR light, enabling real-time visualization of blood flow and tissue perfusion. Its clearance from the circulation is used to assess liver function. These properties make it a valuable tool for various medical diagnostic applications.

In vivo, ICG is used for a variety of diagnostic applications. It is used to determine cardiac output, assess hepatic function, and measure liver and gastric blood flow. It is also used for ophthalmic angiography to visualize retinal and choroidal blood flow. In surgical settings, it is used for fluorescence-guided surgery to visualize vessels, blood flow, and tissue perfusion. It is also used for sentinel lymph node mapping in various cancers.

ICG does not have a classical enzyme/receptor binding assay, as it is a diagnostic dye rather than a pharmacologically active compound. Its interactions are typically studied in the context of its optical properties and pharmacokinetics. Its binding to plasma proteins can be studied using equilibrium dialysis or other protein binding assays. However, these are not typical "activity" assays but rather characterization studies.

Cell Staining Example 1
Indocyanine green is a non-toxic/low toxic fluorescent dye. It can only be taken up by hepatocytes after intravenous injection, after which it is secreted by hepatocytes. When cultured with serum-free medium, hepatocytes take up Indocyanine green, and the cytoplasm appears green. After restoration of serum, Indocyanine green is secreted out of the cytoplasm.
Method: For Indocyanine green uptake assay.
1. Add Indocyanine green to serum-free hepatocyte medium with a final concentration of 1 mg/mL and cells are cultured with the medium for 1 hour at 37℃.
2. Remove serum-free medium, and wash cells with PBS for three times.
3. Cells are examined and imaged with a microscope (IX71FL, OLYMPUS).

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Cell Staining Example 2
Indocyanine green is a non-toxic/low toxic fluorescent dye. It can be taken up by lymph and provides contrast for visualizing the lumen of lymphatic vessels using its single-photon fluorescence in both animal models and human subjects.
Method: For noninvasive 2PF imaging.
ICG is used in cellular assays as a fluorescent probe for imaging and tracking purposes. Cells can be labeled with ICG, and its fluorescence can be detected using NIR imaging systems. Its uptake and retention in cells can be studied using fluorescence microscopy or flow cytometry. However, its primary use is as an in vivo imaging agent rather than a tool for in vitro cellular studies.

In Vivo Staining Example 1
Indocyanine green is a non/low-toxic fluorescent dye that can be used to detect the distribution of polysaccharide-nanoemulsion following oral administration.
Method: For polysaccharide-nanoemulsion distribution detecting.
1. Indocyanine green is dissolved in the polysaccharide aqueous solution and then added to the nanoemulsion to form an complex (The final concentration of Indocyanine green in both solutions is 0.05 mg/mL).
2. A total of 9 BALB/C nude mice are assigned to each of three experimental groups. The mice sre subjected to fasting 4 h following their respective treatment and then placed in a live imaging device (Lumina XR Series III; Perkin-Elmer, Inc) to observe fluorescence distribution in vivo.
In vivo animal studies for ICG are typically conducted to validate its use as a diagnostic imaging agent. Rats with progressive hepatic disease induced by carbon tetrachloride have been used to assess ICG pharmacokinetics as a measure of hepatic function. In these studies, ICG kinetics are used to assess the progression of liver disease. Other animal models are used to validate its use for cardiac output measurement, angiography, and fluorescence-guided surgery.

Absorption, Distribution and Excretion
Following intravenous injection, indocyanine green rapidly binds to plasma proteins, is quickly cleared from circulation via the liver, and is excreted in bile in an unbound form. Studies have shown that the maximum bile excretion rate of indocyanine green in rats (0.065 mg/kg/min) is higher than that in rabbits (0.05 mg/kg/min) or dogs (0.027 mg/kg/min). The half-life increases with increasing dose. …There was a significant difference in clearance time between common mongrel dogs and purebred beagles. At doses above 1 mg/kg, the apparent extractability of indocyanine green in rat livers was surprisingly low. Changes in hepatic blood flow did not alter the clearance rate. For more complete data on absorption, distribution, and excretion of indocyanine green (10 items in total), please visit the HSDB record page. Metabolism/Metabolites …Indocyanine green…is present unchanged in bile.
ICG has a plasma half-life of approximately 150 to 180 seconds (2.5-3 minutes). It is removed from circulation exclusively by the liver and excreted into bile juice in an unconjugated form. It has a clearance rate of 6.8 mL/min/kg. ICG is metabolized in the liver by microsomal enzymes. These pharmacokinetic properties are the basis for its use in assessing hepatic function, as its clearance is dependent on liver blood flow and function.

Effects During Pregnancy and Lactation
◉ Overview of Use During Lactation
Data from one patient showed that low-dose subcutaneous indocyanine green was undetectable in breast milk. Data on larger doses administered intravenously are currently unavailable. Lactating women should use indocyanine green with caution, especially when breastfeeding newborns or preterm infants, until more data become available. ◉ Effects on Breastfed Infants
No published information found as of the revision date. ◉ Effects on Lactation and Breast Milk
No published information found as of the revision date.
Drug Interactions
Enhanced hepatic excretion has been observed after pretreatment with certain drugs. For example, phenobarbital has been shown to increase plasma clearance and bile excretion of indocyanine green. Pretreatment with SKF 525-A inhibited bile secretion of indocyanine green, which has been shown to be due to its temperature effect rather than its effect on the hepatic endoplasmic reticulum. Indocyanine green reduced the initial uptake of ouabain by rat hepatocytes by more than 50%. Data suggest that CMPD may enter hepatocytes via a process similar to active carrier-mediated transport. In male rats intravenously injected with 1.0 mg/kg mercury, indocyanine green inhibited bile excretion of methylmercury. For more complete data on indocyanine green interactions (13 in total), please visit the HSDB records page.
ICG is considered a non-toxic dye. It is FDA-approved for several medical applications, indicating a favorable safety profile. However, adverse reactions can occur, including anaphylactic shock, procedural hypotension, and other reactions. Intravitreal injection of ICG has been shown to be toxic to retinal cells. Patients with liver disease may be at greater risk of drug buildup and toxicity. Overall, it has a well-established safety profile for its approved indications.

[1]. Effect of photodynamic therapy based on indocyanine green on expression of apoptosis-related genes in human gingival fibroblast cells. Photodiagnosis Photodyn Ther. 2017 Apr 21.

Indocyanine green (ICG) is a cyanine dye belonging to the benzoindole class of compounds and is also a 1,1-disubstituted alkyl sulfonate. Indocyanine green is a non-toxic, fluorescent three-carbon cyanine dye with a spectral absorption peak at 790 nm. It can be used to measure cardiac output, liver function, hepatic blood flow, and in ophthalmic angiography. After administration, indocyanine green (ICG) rapidly binds to its primary carrier—plasma proteins—and is thus confined within the vascular lumen. The drug has a half-life of 150 to 180 seconds and is primarily metabolized by the liver and excreted via bile. Furthermore, due to its low uptake rate, ICG is not suitable for angiography or functional output analysis of the kidneys, lungs, brain, spinal cord, or peripheral tissues. A three-carbon cyanine dye used for the diagnosis of liver function tests, as well as for the measurement of blood volume and cardiac output. See also: Indocyanine green acid form (with the active moiety).

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Therapeutic Uses
Dye
Used to measure cardiac output, liver function, and hepatic blood flow. For liver function studies, a calculated amount of diagnostic agent is injected into a vein in the arm. Twenty minutes after injection, 6 ml of venous blood is drawn from the contralateral arm. After coagulation and centrifugation, the absorbance of the clear serum is read at 800-810 nm using a spectrophotometer.
Dye retention in healthy subjects is less than 4%. …If the dye concentration in the serum exceeds 4%, it indicates that the dye cannot be cleared, suggesting impaired liver function.
Typically, when measuring blood volume via intravenous injection, 5 mg of dye is used per ml; when measuring liver function, 0-5 mg of dye is used per kilogram of body weight.
The dye is stable in plasma and whole blood, facilitating subsequent analysis. Different users have different requirements for dye concentration and dosage. The total human dose is usually less than 2 mg/kg body weight.
Drug Warnings
…This product contains a small amount (5%) of sodium iodide; therefore, caution should be exercised in patients with hypersensitivity to iodides. Radioactive iodine uptake studies should not be performed for at least one week after using this product. As probenecid has been shown to affect liver uptake in dogs, this possibility should be considered. The safety of this product during pregnancy has not been established. Please use only freshly prepared solutions as recommended.
Indocyanine Green is an FDA-approved diagnostic agent used for a variety of medical applications. It is used for determining cardiac output, hepatic function, and blood flow, and for ophthalmic angiography. It is also used for fluorescence imaging of vessels, blood flow, and tissue perfusion during surgery. Its rapid hepatic clearance and near-infrared fluorescence make it a valuable tool for real-time imaging and diagnostic assessment. It is approved for clinical use and is widely available as a diagnostic agent.

C43H47N2NAO6S2

774.9629

774.277

C, 66.64; H, 6.11; N, 3.61; Na, 2.97; O, 12.39; S, 8.27

3599-32-4

5282412

Light green to dark green solid powder

157ºC

235 °C

10.555

0

7

12

54

1520

0

S(C([H])([H])C([H])([H])C([H])([H])C([H])([H])[N+]1C2C([H])=C([H])C3=C([H])C([H])=C([H])C([H])=C3C=2C(C([H])([H])[H])(C([H])([H])[H])C=1/C(/[H])=C(/[H])\C(\[H])=C(/[H])\C(\[H])=C(/[H])\C(\[H])=C1/C(C([H])([H])[H])(C([H])([H])[H])C2C3=C([H])C([H])=C([H])C([H])=C3C([H])=C([H])C=2N/1C([H])([H])C([H])([H])C([H])([H])C([H])([H])S(=O)(=O)[O-])(=O)(=O)[O-].[Na+]

MOFVSTNWEDAEEK-UHFFFAOYSA-M

InChI=1S/C43H48N2O6S2.Na/c1-42(2)38(44(28-14-16-30-52(46,47)48)36-26-24-32-18-10-12-20-34(32)40(36)42)22-8-6-5-7-9-23-39-43(3,4)41-35-21-13-11-19-33(35)25-27-37(41)45(39)29-15-17-31-53(49,50)51/h5-13,18-27H,14-17,28-31H2,1-4H3,(H-,46,47,48,49,50,51)/q+1/p-1

sodium 4-(2-((1E,3E,5E,7E)-7-(1,1-dimethyl-3-(4-sulfonatobutyl)-1,3-dihydro-2H-benzo[e]indol-2-ylidene)hepta-1,3,5-trien-1-yl)-1,1-dimethyl-1H-benzo[e]indol-3-ium-3-yl)butane-1-sulfonate

Cardio-Green Fox IR-125 IR 125 IR125

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Note: Please store this product in a sealed and protected environment, avoid exposure to moisture and light.

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

DMSO : ~83.33 mg/mL (~107.53 mM)
H2O : ~5 mg/mL (~6.45 mM)

Solubility in Formulation 1: ≥ 2.5 mg/mL (3.23 mM) (saturation unknown) in 10% DMSO + 40% PEG300 + 5% Tween80 + 45% Saline (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear DMSO stock solution to 400 μL PEG300 and mix evenly; then add 50 μL Tween-80 to the above solution and mix evenly; then add 450 μL normal saline to adjust the volume to 1 mL.
Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH₂ O to obtain a clear solution.

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Solubility in Formulation 2: 2.5 mg/mL (3.23 mM) in 10% DMSO + 90% (20% SBE-β-CD in Saline) (add these co-solvents sequentially from left to right, and one by one), suspension solution; with ultrasonication.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear DMSO stock solution to 900 μL of 20% SBE-β-CD physiological saline solution and mix evenly.
Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution.

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 (Please use freshly prepared in vivo formulations for optimal results.)