Macrolide antibiotic

Plasmodium falciparum is inhibited by erythromycin thiocyanate, with IC50 and IC90 values of 58.2 μM and 104.0 μM, respectively [1]. Antioxidant and anti-inflammatory properties of erythromycin thiocyanate (10 μM, 100 μM; 24 hours, 72 hours) include inhibiting the formation of 4-HNE (p<0.01) and 8-OHdG (p<0.01), reducing Iba-1 (p<0.01), and dramatically reducing TNF-α (p<0.01) [4].

Mice given erythromycin thiocyanate (0.1–50 mg/kg; 30-120 days) at a dose of 5 mg/kg have tumor growth inhibition and longer survival times [3]. Even 120 days after injection, mice protected against tumor growth by erythromycin thiocyanate (gastric intubation; 5 mg/kg); however, a 50 mg/kg dose reduced the average life period of tumor-bearing mice by 4–5 days[3]. In a rat model of cerebral ischemia-reperfusion injury, erythromycin thiocyanate (ih; single injection; 50 mg/kg) exhibits a protective effect [4].

Cell viability assay [4]
Cell Types: Embryonic primary cortical neurons (from the cerebral cortex of 17-day-old Sprague-Dawley rats)
Tested Concentrations: 10, 100 μM
Incubation Duration: 24, 72 hrs (hours)
Experimental Results: Improved viability of cultured neurons 3 hrs (hours) of oxygen-glucose deprivation (OGD) in vitro cells.

Animal/Disease Models: Female ddY mice (6 weeks old) with EAC cells or CDF mice (6 weeks old) with P388 cells [3]
Doses: 0.1 mg/kg; 0.5 mg/kg; 10 mg/kg ; 30 mg/kg; 50 mg/kg
Route of Administration: gastric intubation; 30-120 days
Experimental Results: After the 5 mg/kg dose, tumor growth was diminished and the average survival time of mice was prolonged, but the 50 mg/kg dose shortened the load. MST of tumor mice.

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Animal/Disease Models: Male SD (SD (Sprague-Dawley)) rats (8 weeks old, 250-300 g) [4]
Doses: 50 mg/kg
Route of Administration: Single subcutaneous injection
Experimental Results: Reduce infarct volume and edema volume, and improve neurological deficits.

Absorption, Distribution and Excretion
Orally administered erythromycin is readily absorbed. Food intake does not appear to exert effects on serum concentrations of erythromycin. Some interindividual variation exists in terms of erythromycin absorption, which may impact absorption to varying degrees. The Cmax of erythromycin is 1.8 mcg/L and the Tmax is 1.2 hours. The serum AUC of erythromycin after the administration of a 500mg oral dose was 7.3±3.9 mg.h/l in one pharmacokinetic study. Erythromycin is well known for a bioavailability that is variable (18-45%) after oral administration and its susceptibility to broken down under acidic conditions.
In patients with normal liver function, erythromycin concentrates in the liver and is then excreted in the bile.Under 5% of the orally administered dose of erythromycin is found excreted in the urine. A high percentage of absorbed erythromycin is not accounted for, but is likely metabolized.
Erythromycin is found in most body fluids and accumulates in leucocytes and inflammatory liquid. Spinal fluid concentrations of erythromycin are low, however, the diffusion of erythromycin through the blood-brain barrier increases in meningitis, likely due to the presence of inflamed tissues which are easily penetrated. Erythromycin crosses the placenta.
The clearance of erythromycin in healthy subjects was 0.53 ± 0.13 l/h/kg after a 125mg intravenous dose. In a clinical study of healthy patients and patients with liver cirrhosis, clearance of erythromycin was significantly reduced in those with severe liver cirrhosis. The clearance in cirrhotic patients was 42.2 ± 10.1 l h–1 versus 113.2 ± 44.2 l h-1 in healthy patients.
Absorption of orally administered erythromycins occurs mainly in the duodenum. The bioavailability of the drugs is variable and depends on several factors including the particular erythromycin derivative, the formulation of the dosage form administered, acid stability of the derivative, presence of food in the GI tract, and gastric emptying time.
Erythromycin is rather slowly absorbed after oral administration. peak serum concentrations ranged from 0.1 to 4.8 ug/mL according to the form and the coating of erythromycin administered. The oral absorption is less that 50% and erythromycin is degraded by gastric acid. It is absorbed in the small intestine (mainly in duodenum for humans) as erythromycin base.
Erythromycin diffuses readily into intracellular fluids, achieving antibacterial activity in essentially all sites except the brain and CSF. Erythromycin penetrates into prostatic fluid, achieving concentrations approximately 40% of those in plasma. Concentrations in middle ear exudate reach only 50% of serum concentrations and thus may be inadequate for the treatment of otitis media caused by H. influenzae. Protein binding is approximately 70% to 80% for erythromycin base and even higher, 96%, for the estolate. Erythromycin traverses the placenta, and drug concentrations in fetal plasma are about 5% to 20% of those in the maternal circulation. Concentrations in breast milk are 50% of those in serum.
In an in vitro model using human skin, erythromycin was absorbed into the stratum corneum following topical application of 10-20 mg of the drug in a vehicle containing dimethylacetamide and 95% alcohol. The drug does not appear to be absorbed systemically following twice daily application of a 2% solution of the drug in a vehicle containing 77% alcohol and polyethylene glycol and acetone. It is not known if erythromycin is absorbed from intact or denuded skin, wounds, or mucous membranes following topical application of an ointment containing the drug.
For more Absorption, Distribution and Excretion (Complete) data for Erythromycin (13 total), please visit the HSDB record page.
PEAK CONCN IN PLASMA...0.3-0.5 UG/ML 4 HR AFTER ORAL ADMIN OF 250 MG OF BASE & ARE 0.3-1.9 UG/ML AFTER...500-MG TABLET. VARIOUS ESTERS OF ERYTHROMYCIN HAVE BEEN PREPARED TO...IMPROVE STABILITY & FACILITATE ABSORPTION. ...CONCN OF ERYTHROMYCIN IN PLASMA ARE LITTLE DIFFERENT IF STEARATE IS GIVEN ORALLY.
...DIFFUSES READILY INTO INTRACELLULAR FLUIDS, & ANTIBACTERIAL ACTIVITY... ACHIEVED AT...ALL SITES EXCEPT BRAIN & CSF. ...ONE OF FEW ANTIBIOTICS THAT PENETRATES INTO PROSTATIC FLUID, CONCN ARE APPROX 40% OF...PLASMA. EXTENT OF BINDING...TO PLASMA PROTEINS VARIES...PROBABLY EXCEEDS 70% IN ALL.../FORMS OF DRUG/. /ERYTHROMYCIN/
ERYTHROMYCIN BASE IS ADEQUATELY ABSORBED FROM UPPER PART OF SMALL INTESTINE; IT IS INACTIVATED BY GASTRIC JUICE... FOOD IN STOMACH DELAYS ITS ULTIMATE ABSORPTION. /ERYTHROMYCIN/
ERYTHROMYCIN TRAVERSES PLACENTAL BARRIER; & CONCN OF DRUG IN FETAL PLASMA ARE ABOUT 5-20% OF THOSE IN MATERNAL CIRCULATION. /ERYTHROMYCIN/
For more Absorption, Distribution and Excretion (Complete) data for ERYTHROMYCIN STEARATE (11 total), please visit the HSDB record page.

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Metabolism / Metabolites
Hepatic first-pass metabolism contributes significantly to erythromycin metabolism after an oral dose. Erythromycin is partially metabolized by CYP3A4 enzyme to N-desmethylerythromycin. Erythromycin is also hydrolyzed to _anhydro_ forms (anhydroerythromycin [AHE] and other metabolites), and this process is promoted by acidic conditions. AHE is inactive against microbes but inhibits hepatic drug oxidation and is therefore considered to be an important contributor to erythromycin drug-drug interactions.
Twenty hours after an oral administration of 10 mg erythromycin to rats, about 37-43% of the administered radioactivity was recovered in the intestinal tract plus feces, 27.2 to 36.1% in the urine, 21-29% in the expired air. It was rapidly metabolized in the liver, mainly through demethylation process, and excreted in the bile as des-N-methyl-erythromycin, the major metabolite present only in the bile and in the intestinal contents of rats. The isotropic methyl group was eliminated in the expired air as CO2.
IT IS HYDROLYZED IN SMALL INTESTINE & IN TISSUES TO YIELD ERYTHROMYCIN.
Hepatic. Extensively metabolized - after oral administration, less than 5% of the administered dose can be recovered in the active form in the urine. Erythromycin is partially metabolized by CYP3A4 resulting in numerous drug interactions.
Half Life: 0.8 - 3 hours

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Biological Half-Life
The elimination half-life of oral erythromycin was 3.5 hours according to one study and ranged between 2.4-3.1 hours in another study. Repetitive dosing of erythromycin leads to increased elimination half-life.
... The serum elimination half-life of erythromycin is approximately 1.6 hours.
The serum half-life in normal subjects is 2 hours and in anuric subjects, 4-6 hours.

Toxicity Summary
Erythromycin acts by penetrating the bacterial cell membrane and reversibly binding to the 50 S subunit of bacterial ribosomes or near the “P” or donor site so that binding of tRNA (transfer RNA) to the donor site is blocked. Translocation of peptides from the “A” or acceptor site to the “P” or donor site is prevented, and subsequent protein synthesis is inhibited. Erythromycin is effective only against actively dividing organisms. The exact mechanism by which erythmromycin reduces lesions of acne vulgaris is not fully known: however, the effect appears to be due in part to the antibacterial activity of the drug.

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Interactions
Erythromycin is metabolized by CYP3A and concomitant use with drugs that inhibit the CYP3A isoenzyme may result in increased erythromycin plasma concentrations. There is some evidence that concomitant use of oral erythromycin with drugs that inhibit CYP3A (i.e., fluconazole, ketoconazole, itraconazole, diltiazem, verapamil) is associated with an increased incidence of sudden death from cardiac causes, presumably because of increased plasma erythromycin concentrations resulting in an increased risk of QT prolongation (a dose-associated effect of erythromycin) and serious ventricular arrhythmias. Therefore, it has been suggested that concomitant use of erythromycin and drugs that are potent inhibitors of CYP3A should be avoided.
Erythromycin may interact with astemizole and terfenadine (both drugs no longer commercially available in the US), resulting in potentially serious adverse cardiovascular effects. Some evidence indicates that erythromycin may alter the metabolism of astemizole and terfenadine, probably via inhibition of the cytochrome P-450 microsomal enzyme system. While erythromycin has been shown to decrease markedly the clearance of the active carboxylic acid metabolite of terfenadine, the effect of the macrolide on unchanged terfenadine concentrations has not been fully elucidated, but appears to show interindividual variation. In studies in extensive metabolizers of dextromethorphan or debrisoquin, erythromycin markedly impaired clearance of the active metabolite of terfenadine in all such individuals but produced measurable effects on unchanged terfenadine in only one-third of these individuals. In addition, erythromycin is known to inhibit the enzyme system responsible for astemizole's metabolism. Prolongation of the QT interval and ventricular tachycardia, including torsades de pointes, have been reported in some patients receiving astemizole or terfenadine concomitantly with erythromycin or the structurally related macrolide troleandomycin (no longer commercially available in the US). Rarely, cardiac arrest and death have been reported in patients receiving erythromycin and terfenadine concomitantly. Therefore, when terfenadine and astemizole were commercially available in the US, these antihistamines were contraindicated in patients receiving erythromycin, clarithromycin, or troleandomycin. In addition, concomitant administration of astemizole or terfenadine and azithromycin also was not recommended, although limited data suggested that azithromycin did not alter the metabolism of terfenadine.
Although in vitro studies have shown varying degrees of additive or synergistic effects against some organisms when erythromycin was used in conjunction with penicillins, streptomycin, sulfonamides, rifampin, or chloramphenicol, the clinical importance of these reports has not been established. Antagonism of bactericidal activity has been observed between erythromycin and clindamycin in vitro. In addition, antagonism has been reported when a bacteriostatic drug was administered with a bactericidal drug, but antagonism has not been convincingly documented clinically.
Concomitant use of erythromycin in patients receiving high dosage of theophylline has resulted in decreased clearance of theophylline, elevated serum theophylline concentrations, and a prolonged serum half-life of the bronchodilator. An interaction may be most likely to occur in patients receiving an erythromycin dosage greater than 1.5 g daily for more than 5 days. Patients receiving theophylline should be closely monitored for signs of theophylline toxicity when erythromycin is administered concomitantly; serum theophylline concentrations should be monitored and dosage of the bronchodilator reduced if indicated. Although further study is needed and the clinical importance has not been determined to date, there is some evidence that concomitant administration of erythromycin and theophylline can also result in decreased serum erythromycin concentrations and subtherapeutic concentrations of erythromycin may occur.
For more Interactions (Complete) data for Erythromycin (22 total), please visit the HSDB record page.
A 77-YR-OLD WOMAN IS REPORTEDLY MAINTAINED ON 7.5 MG OF WARFARIN DAILY IN WHOM THE ADMIN OF ORAL ERYTHROMYCIN STEARATE, 500 MG 4 TIMES A DAY, RESULTED IN A PROTHROMBIN TIME OF 64 SECONDS (CONTROL, 11 SECONDS).

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Non-Human Toxicity Values
LD50 Rat oral 9272 mg/kg
LD50 Mouse ip 463 mg/kg
LD50 Mouse sc 1800 mg/kg
LD50 Mouse im 426 mg/kg
For more Non-Human Toxicity Values (Complete) data for Erythromycin (6 total), please visit the HSDB record page.

[1]. Erythromycin. Med Clin North Am. 1982 Jan;66(1):79-89.

[2]. Activity of azithromycin or erythromycin in combination with antimalarial drugs against multidrug-resistant Plasmodium falciparum in vitro. Acta Trop. 2006 Dec;100(3):185-91. Epub 2006 Nov 28.

[3]. Antitumor effect of erythromycin in mice. Chemotherapy. 1995 Jan-Feb. 41(1):59-69.

[4]. Neuroprotective effects of erythromycin on cerebral ischemia reperfusion-injury and cell viability after oxygen-glucose deprivation in cultured neuronal cells. Brain Res. 2014 Nov 7. 1588:159-67.

Therapeutic Uses
Antibiotics, Macrolide; Gastrointestinal Agents; Protein Synthesis Inhibitors
MEDICATION (VET): In veterinary medicine, /erythromycin/ is used the treatment of clinical and subclinical mastitis in lactating cows, for the treatment of infectious diseases due to erythromycin-sensitive bacteria (cattle, sheep, swine, poultry) and for the treatment of chronic respiratory diseases due to mycoplasma in poultry.
Erythromycin is used as an alternative agent in the treatment of anthrax. Parenteral penicillins generally have been considered the drugs of choice for the treatment of naturally occurring or endemic anthrax caused by susceptible strains of Bacillus anthracis, including clinically apparent GI, inhalational, or meningeal anthrax and anthrax septicemia, although IV ciprofloxacin or IV doxycycline also are recommended. Erythromycin is suggested as an alternative to penicillin G for the treatment of naturally occurring or endemic anthrax in patients hypersensitive to penicillins. ./NOT included in US product label/
Erythromycin is used topically in the treatment of acne vulgaris. Therapy of acne vulgaris must be individualized and frequently modified depending on the types of acne lesions which predominate and the response to therapy. Topical anti-infectives, including erythromycin, are generally effective in the treatment of mild to moderate inflammatory acne. However, use of topical anti-infectives as monotherapy may lead to bacterial resistance; this resistance is associated with decreased clinical efficacy. Topical erythromycin is particularly useful when used with benzoyl peroxide or topical retinoids. Results of clinical studies indicate that combination therapy results in a reduction in total lesion counts of 50 to 70%. /Included in US product label/
For more Therapeutic Uses (Complete) data for Erythromycin (23 total), please visit the HSDB record page.
ITS ACTIONS & USES ARE IDENTICAL TO THOSE OF ERYTHROMYCIN.
ERYTHROMYCIN MAY BE USEFUL FOR DISSEMINATED GONOCOCCAL DISEASE IN PREGNANT PT WHO IS ALLERGIC TO PENICILLIN... 13 PT...TREATED WITH 500 MG OF ERYTHROMYCIN... STEARATE, GIVEN ORALLY EVERY 6 HR FOR 5 DAYS, SHOWED RAPID CLINICAL & BACTERIOLOGICAL RESPONSES.
ANTIBACTERIAL AGENT
MEDICATION (VET): ANTIBACTERIAL AGENT

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Drug Warnings
Some commercially available formulations of erythromycin lactobionate powder for injection contain benzyl alcohol as a preservative. Although a causal relationship has not been established, administration of injections preserved with benzyl alcohol has been associated with toxicity in neonates. Toxicity appears to have resulted from administration of large amounts (i.e., about 100-400 mg/kg daily) of benzyl alcohol in these neonates. Although use of drugs preserved with benzyl alcohol should be avoided in neonates whenever possible, the American Academy of Pediatrics states that the presence of small amounts of the preservative in a commercially available injection should not proscribe its use when indicated in neonates. /Erythromycin lactobionate/
In several neonates with infections caused by Ureaplasma urealyticum who received IV administration of erythromycin lactobionate, adverse cardiac effects (e.g., bradycardia, hypotension, cardiac arrest, arrhythmias) requiring cardiopulmonary resuscitation have been reported. Some clinicians state that these adverse effects may depend on serum concentration and/or infusion rate of the drug. It has been suggested that prolonged IV infusion of erythromycin lactobionate (e.g., over 60 minutes) may reduce such adverse cardiac effects. However, it has been suggested that certain individuals may be at increased risk of developing erythromycin-induced adverse cardiac effects and that decreasing the rate of IV infusion may decrease but not eliminate the risk of such effects. Further study is needed to determine the pharmacokinetics and safety of erythromycin lactobionate in neonates. /Erythromycin lactobionate/
Maternal Medication usually Compatible with Breast-Feeding: Erythromycin: Reported Sign or Symptom in Infant or Effect on Lactation: None. /From Table 6/
POTENTIAL ADVERSE EFFECTS ON FETUS: None known. POTENTIAL SIDE EFFECTS ON BREAST-FED INFANT: None known, although theoretically could cause diarrhea in infant. COMMENTS: Crosses placenta in high doses to fetal level 24% of maternal; breast milk may exceed maternal serum concentration. FDA Category: B (B = Studies in laboratory animals have not demonstrated a fetal risk, but there are no controlled studies in pregnant women; or animal studies have shown an adverse effect (other than a decrease in fertility), but controlled studies in pregnant women have not demonstrated a risk to the fetus in the first trimester and there is no evidence of a risk in later trimesters.) /From Table II/
For more Drug Warnings (Complete) data for Erythromycin (17 total), please visit the HSDB record page.
...ERYTHROMYCIN & ITS DERIV SELDOM CAUSE SERIOUS ADVERSE REACTIONS.

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Pharmacodynamics
Macrolides, such as erythromycin, stop bacterial growth by inhibiting protein synthesis and translation, treating bacterial infections. Erythromycin does not exert effects on nucleic acid synthesis. This drug has been shown to be active against most strains of the following microorganisms, effectively treating both in vitro and clinical infections. Despite this, it is important to perform bacterial susceptibility testing before administering this antibiotic, as resistance is a common issue that may affect treatment. **A note on antimicrobial resistance, pseudomembranous colitis, and hepatotoxicity** Many strains of Haemophilus influenzae are resistant to erythromycin alone but are found to be susceptible to erythromycin and sulfonamides used in combination. It is important to note that Staphylococci that are resistant to erythromycin may emerge during erythromycin and/or sulfonamide therapy. Pseudomembranous colitis has been reported with most antibacterial agents, including erythromycin, and may range in severity from mild to life-threatening. Therefore, the physician should consider this diagnosis in patients with diarrhea after the administration of antibacterial agents. Erythromycin can cause hepatic dysfunction, cholestatic jaundice, and abnormal liver transaminases, particularly when erythromycin estolate is administered.

C₃₈H₆₈N₂O₁₃S

793.02

791.436

7704-67-8

Erythromycin;114-07-8;Erythromycin stearate;643-22-1

12560

White to off-white solid powder

818.4ºC at 760 mmHg

212 to 219 °F (NTP, 1992)
133-135
191 °C
After melting /at 135-140 °C, it/ resolidifies with second melting point 190-193 °C. ... Readily forms salts with acids
MP: 92 °C. Slightly soluble in ethanol, ethyl ether, chloroform; insoluble in water. /Erythromycin stearate/
Crystals from acetone aqueous. MP: 222 °C. MW: 862.05. /Erythromycin ethyl succinate/
191 °C

448.8ºC

2.182

5

14

7

51

1180

18

CC[C@@H]1[C@](C)([C@@H]([C@@H](C)C(=O)[C@H](C)C[C@](C)([C@@H]([C@@H](C)[C@@H]([C@@H](C)C(=O)O1)O[C@H]2C[C@](C)([C@H]([C@H](C)O2)O)OC)O[C@H]3[C@@H]([C@H](C[C@@H](C)O3)N(C)C)O)O)O)O.C(#N)S

WVRRTEYLDPNZHR-YZPBMOCRSA-N

InChI=1S/C37H67NO13.CHNS/c1-14-25-37(10,45)30(41)20(4)27(39)18(2)16-35(8,44)32(51-34-28(40)24(38(11)12)15-19(3)47-34)21(5)29(22(6)33(43)49-25)50-26-17-36(9,46-13)31(42)23(7)48-26;2-1-3/h18-26,28-32,34,40-42,44-45H,14-17H2,1-13H3;3H/t18-,19-,20+,21+,22-,23+,24+,25-,26+,28-,29+,30-,31+,32-,34+,35-,36-,37-;/m1./s1

(3R,4S,5S,6R,7R,9R,11R,12R,13S,14R)-6-[(2S,3R,4S,6R)-4-(dimethylamino)-3-hydroxy-6-methyloxan-2-yl]oxy-14-ethyl-7,12,13-trihydroxy-4-[(2R,4R,5S,6S)-5-hydroxy-4-methoxy-4,6-dimethyloxan-2-yl]oxy-3,5,7,9,11,13-hexamethyl-oxacyclotetradecane-2,10-dione;thiocyanic acid

Erythromycin thiocyanate; Erythromycin (thiocyanate); Erythromycin, thiocyanate (salt); UNII-Y7A95YRI88

2941500000

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.

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

DMSO : ~100 mg/mL (~126.10 mM)

Note: Listed below are some common formulations that may be used to formulate products with low water solubility (e.g. < 1 mg/mL), you may test these formulations using a minute amount of products to avoid loss of samples.

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Injection Formulation 1: DMSO : Tween 80： Saline = 10 : 5 : 85 (i.e. 100 μL DMSO stock solution → 50 μL Tween 80 → 850 μL Saline)
*Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH ₂ O to obtain a clear solution.
Injection Formulation 2: DMSO : PEG300 ：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL DMSO → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)
Injection Formulation 3: DMSO : Corn oil = 10 : 90 (i.e. 100 μL DMSO → 900 μL Corn oil)
Example: Take the Injection Formulation 3 (DMSO : Corn oil = 10 : 90) as an example, if 1 mL of 2.5 mg/mL working solution is to be prepared, you can take 100 μL 25 mg/mL DMSO stock solution and add to 900 μL corn oil, mix well to obtain a clear or suspension solution (2.5 mg/mL, ready for use in animals).

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Injection Formulation 4: DMSO : 20% SBE-β-CD in saline = 10 : 90 [i.e. 100 μL DMSO → 900 μL (20% SBE-β-CD in saline)]
*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.
Injection Formulation 5: 2-Hydroxypropyl-β-cyclodextrin : Saline = 50 : 50 (i.e. 500 μL 2-Hydroxypropyl-β-cyclodextrin → 500 μL Saline)
Injection Formulation 6: DMSO : PEG300 : castor oil : Saline = 5 : 10 : 20 : 65 (i.e. 50 μL DMSO → 100 μLPEG300 → 200 μL castor oil → 650 μL Saline)
Injection Formulation 7: Ethanol : Cremophor : Saline = 10： 10 : 80 (i.e. 100 μL Ethanol → 100 μL Cremophor → 800 μL Saline)
Injection Formulation 8: Dissolve in Cremophor/Ethanol (50 : 50), then diluted by Saline
Injection Formulation 9: EtOH : Corn oil = 10 : 90 (i.e. 100 μL EtOH → 900 μL Corn oil)
Injection Formulation 10: EtOH : PEG300：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL EtOH → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)

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Oral Formulation 1: Suspend in 0.5% CMC Na (carboxymethylcellulose sodium)
Oral Formulation 2: Suspend in 0.5% Carboxymethyl cellulose
Example: Take the Oral Formulation 1 (Suspend in 0.5% CMC Na) as an example, if 100 mL of 2.5 mg/mL working solution is to be prepared, you can first prepare 0.5% CMC Na solution by measuring 0.5 g CMC Na and dissolve it in 100 mL ddH2O to obtain a clear solution; then add 250 mg of the product to 100 mL 0.5% CMC Na solution, to make the suspension solution (2.5 mg/mL, ready for use in animals).

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Oral Formulation 3: Dissolved in PEG400
Oral Formulation 4: Suspend in 0.2% Carboxymethyl cellulose
Oral Formulation 5: Dissolve in 0.25% Tween 80 and 0.5% Carboxymethyl cellulose
Oral Formulation 6: Mixing with food powders

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Note: Please be aware that the above formulations are for reference only. InvivoChem strongly recommends customers to read literature methods/protocols carefully before determining which formulation you should use for in vivo studies, as different compounds have different solubility properties and have to be formulated differently.

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