The effects of glycolic acid (GA) or LA at different doses (300 and 500 mg/mL) on the development of human and mouse melanoma cells were investigated. Even after five days at a 300 mg/mL concentration of each drug, both types of cells expanded effectively. On the other hand, 500 mg/mL LA and 500 mg/mL glycolic acid both decreased the development of human and mouse melanoma cells (27% and 36%, respectively) [1].

Absorption, Distribution and Excretion
This study used isolated Yucatan from miniature pig epidermis and full-thickness hairless mouse skin to investigate the permeability of 10% glycolic acid aqueous solutions adjusted to pH 3.8 with ammonium hydroxide or sodium hydroxide. 200 μL of each formulation was applied to a region of a Franz diffusion cell, and the permeability of glycolic acid was analyzed using liquid scintillation counting. With closed patches, permeation was linear with a hysteresis time of less than 15 mm. After 8 hours, the permeabilities of ammonium hydroxide and sodium hydroxide were 0.8% and 1.6% in the pig skin model, respectively; and 1.8% and 2.3% in the mouse skin model, respectively. Under open patch conditions, permeation was non-linear with a hysteresis time greater than 15 mm. With the pig skin model, the permeabilities of ammonium and sodium salts were 1.1% and 0.7%, respectively; and with the mouse skin model, the permeabilities were 0.6% and 0.9%, respectively.
The skin permeability of (14)C-glycolic acid was studied in vitro by applying an ointment at a dose of 5 mg/0.79 cm² to pig skin without using occlusive patches. Results showed that 3.1% of the applied glycolic acid permeated the skin.
Two female rhesus monkeys were orally administered 4 mL/kg of homogeneous 1-(14)C-glycolic acid aqueous solution (concentration 0.73 μC/mmol, concentration 500 mg/kg) via gastric tube. Urine was collected at time intervals of 0–8 hours, 8–24 hours, 24–48 hours, 48–72 hours, and (for one monkey) 72–96 hours. Within 72 hours, one animal excreted 53.2% of the (14)C (percentage of total dose), of which 51.4% was excreted in urine; 51.4% of the dose was excreted within the first 24 hours. Another animal excreted a total of 42.2% of (14)C over 96 hours, of which 36.6% was excreted in urine; 34.1% of the dose was excreted in the first 24 hours. (The higher radioactivity observed in the monkey's feces was likely due to radioactive contamination of the urine.) Only a very small amount was converted into radioactive glyoxylic acid, hippuric acid, or oxalic acid.
In vitro, the skin permeability of a 10% glycolic acid aqueous solution was determined using abdominal skin from an 87-year-old woman. A glycolic acid aqueous solution was prepared by adding 0.8 mL of 12.473% glycolic acid solution to 0.2 mL of (2-(14)C) glycolic acid solution containing 0.216 mg glycolic acid (44 mCi/mmol or 250 iCi/mL). The pH of the mixture containing 0.8 mL of 12.473% glycolic acid solution and 0.2 mL of water was 3.72. Skin integrity was assessed by determining the permeability coefficient of the tritium-contaminated water. 20 μL of 10% glycolic acid aqueous solution. A 2 mg solution of glycolic acid, the active ingredient, was applied to the stratum corneum surface, repeated 13 times. 200 μL samples were taken at 1, 2, 4, 6, 8, and 24 hours after application and counted using a liquid scintillation counter. After 24 hours, the skin surface was rinsed three times with water. The average total absorption over 24 hours was 2.6 ± 0.37 μg/cm², equivalent to 0.15 ± 0.02% of the applied dose. After a hysteresis period of approximately 3.8 hours, steady-state diffusion occurred at a rate of 0.13 μg/cm²/h. After 24 hours, 48 ± 0.05% of the dose was recovered in the skin, and 0.15 ± 0.02% was recovered in the receptor phase. The overall recovery rate was 102.9% ± 2.9%.
For more complete data on absorption, distribution, and excretion of glycolic acid (14 types), please visit the HSDB record page.

---

Metabolism/Metabolites
This study compared the pharmacokinetics of ethylene glycol (EG) and its major metabolites glycolic acid (GA) and oxalic acid (OX) administered orally to pregnant (P; day 10 of gestation, GD 10) rats, and compared the differences between different dose groups and between pregnant and non-pregnant (NP) rats. Four female rats in each group, cannulated by the jugular vein, were administered 10 (P and NP), 150 (P), 500 (P), 1000 (P), or 2500 (P and NP) mg (13)C-labeled EG/kg body weight. Blood and urine samples were collected continuously within 24 hours after administration, and the concentrations of EG, GA, and OX were analyzed by gas chromatography-mass spectrometry (GC/MS). Pharmacokinetic parameters of EG and GA, including Cmax, Tmax, AUC, and β-t(1/2), were determined. Pregnancy status (days 10-11 of gestation) had no effect on the pharmacokinetic parameters studied. Within the dose range of 10 to 150 mg EG/kg, GA plasma concentrations were roughly dose-proportional, but in the dose range of 500 to 1000 mg EG/kg, GA plasma concentrations increased disproportionately. At EG doses ≥500 mg/kg, both EG and GA exhibited dose-dependent urinary excretion, likely due to the saturation of EG metabolism to GA and GA metabolism to downstream metabolites. The shift to nonlinear kinetics encompassed both the no-effect level (NOEL, 500 mg EG/kg) and the lowest effective level (LOEL, 1000 mg EG/kg) of EG in rat developmental toxicity, providing further evidence for the role of GA in EG developmental toxicity. Peak maternal blood GA concentrations associated with the LOEL of rat developmental toxicity were considerably high (363 μg/g or 4.8 mM blood). At all dose levels, OX levels in blood and urine were extremely low, indicating that OX is not significant for EG developmental toxicity.
In Fischer 344 rats, the distribution of dichloroacetic acid (DCA) over 48 hours following gavage administration of 282 mg/kg 1- or 2-(14C)DCA (1-DCA or 2-DCA) and 28.2 mg/kg 2-DCA… The main urinary metabolites were glycolic acid, glyoxylic acid, and oxalic acid. DCA and its metabolites accumulated in tissues and were slowly excreted…
In male Sprague-Dawley rats and mixed-breed dogs, the accumulation of glycolic acid and the elimination kinetics of ethylene glycol (EG) were investigated… EG was administered via gavage… Peak plasma concentrations of EG occurred 2 hours after administration, while peak plasma concentrations of glycolic acid occurred 4–6 hours after administration. The elimination rate of EG in rats was slightly faster than in dogs, with a half-life of 1.7 hours compared to 3.4 hours in dogs. Peak plasma concentrations of glycolic acid in rats were higher than in dogs, but the accumulation pattern was similar to that in dogs. Glycolic acid and EG disappeared from the plasma simultaneously, indicating that the elimination rate of its metabolites was slower than that of EG. Renal excretion is an important clearance route for EG, accounting for approximately 20-30% of the administered dose. The renal excretion of glycolic acid accounts for approximately 5% of the administered dose... /glycolic acid /
To determine the tissue distribution and metabolic pathway of 1,2-(14)C-ethylene glycol (EG) after intravenous (iv), oral (po), and percutaneous (pc) administration, we administered EG to female Sprague-Dawley rats and CD-1 mice. Rats were given doses of 10 or 1000 mg/kg via intravenous and oral routes, respectively, with additional percutaneous doses of 400, 600, or 800 mg/kg. Mice were also given intravenous and oral doses of 10 or 1000 mg/kg, respectively, with intermediate oral doses of 100, 200, or 400 mg/kg. Mice were also administered oral doses of 100 or 1000 mg/kg, and both animals were given oral doses of a 50% (w/w) aqueous solution to simulate antifreeze exposure. Ethylene glycol (EG) was rapidly and almost completely absorbed after oral administration in both animals. Tissue distribution of EG was substantially similar after intravenous or oral administration, and the recovery rates at each dose were similar in both routes and animals. Compared to oral administration, dermal application of EG resulted in slower and lower absorption rates in both animals, and urinary analysis following undiluted oral administration suggested that EG may have permeated rat skin unchanged. No dose-dependent changes in in vivo distribution and elimination were observed after subcutaneous application of EG in either animal. ¹⁴C-labeled EG, glycolic acid, and/or oxalic acid constituted the majority of the radioactive components detectable in rat urine samples from all routes of administration, while glycolaldehyde and glyoxylic acid were not detected in any of the evaluated urinary components. A similar phenomenon of increased glycolic acid production with increasing dose was observed in mouse urine samples from intravenous and oral administration. Furthermore, glyoxylic acid and oxalic acid were not detected in mouse urine…
For more complete data on the metabolism/metabolites of glycolic acid (9 metabolites in total), please visit the HSDB record page.
The main degradation pathway of glycolic acid is the formation of glyoxylic acid. This reaction is mediated by lactate dehydrogenase or glycolate oxidase. After the formation of glyoxylic acid, it appears to be rapidly degraded into a variety of products, some of which have been observed. It is speculated that its breakdown into 2-hydroxy-3-oxoadipic acid is mediated by thiamine pyrophosphate in the presence of magnesium ions. The formation of glycine involves pyridoxal phosphate and glyoxylate transaminase, while the process of producing carbon dioxide and water via formic acid apparently involves coenzyme A (CoA) and flavin mononucleotide. (T29)

---

Biological half-life
…Ethylene glycol and glycolic acid are distributed in the body's water, with plasma half-lives of 8.4 hours and 7.0 hours, respectively. Assuming that diethylene glycol elimination follows first-order kinetics, after administration of 1, 5, and 10 mL/kg diethylene glycol to rats, diethylene glycol was excreted in the urine with half-lives of 6, 6, and 12 hours, respectively. More detailed analysis showed that after administration of 1, 5, and 10 mL/kg diethylene glycol to rats, at 6, 9, and 18 hours, the elimination of 14C activity followed zero-order kinetics, then transitioned to first-order kinetics with a half-life of 3 hours. After administration of 3 and 5 mL/kg ethylene glycol to rats, unmetabolized ethylene glycol was excreted in the urine with half-lives of 4.5 hours and 4.1 hours, respectively.

Toxicity Summary
Identification and Uses: Glycolic acid (GA) is an odorless, colorless, translucent solid. Its primary uses are in cleaning and metalworking. Other specific uses include biomedical applications, printed circuit board flux, adhesives, textiles, hydrogen sulfide removal, tanning, oil well acidification, and biodegradable polymers and copolymers for absorbable sutures and drug delivery systems. It is also used as an exfoliant and keratolytic agent in skin care products. Human Contact and Toxicity: Inhalation may irritate mucous membranes, causing upper respiratory tract and bronchial irritation. Skin contact may cause severe skin irritation, accompanied by discomfort or rash. High concentrations or prolonged exposure may cause skin burns or ulcers. Eye contact may cause eye corrosion, causing corneal or conjunctival ulcers. Permanent eye damage may occur. Ingestion may cause mucous membrane corrosion, causing stomach upset, nausea, and weakness. Overdose may cause kidney damage or even death. Animal toxicity studies: After feeding rats a basal diet containing 3% glycolic acid for 3 weeks, a high incidence of calcium oxalate urinary tract stones was observed (primarily in the kidneys, but stones were also found in the ureters and bladder in some animals). Furthermore, fine crystalline deposits were observed in both the renal cortex and medulla, and clusters of stones were visible on or inside the renal papillae. In dogs, oral administration of 1000 mg glycolic acid daily for 35 days did not reveal abnormal oxalate secretion, nor were any gastrointestinal or renal injuries reported. In another experiment, rats were administered the test substance by gavage up to 600 mg/kg/day for 90 days. Two male rats in the 600 mg/kg/day dose group died. Mean body weight, total weight gain, food consumption, and food utilization were all decreased in both male and female rats. Microscopic manifestations of oxalate crystal nephropathy and unilateral hydronephrosis, as well as transitional epithelial hyperplasia of the renal pelvis (males only), were observed in the 300 and 600 mg/kg/day dose groups. At these dose levels, microscopic manifestations of oxalate crystal nephropathy and unilateral hydronephrosis, as well as transitional epithelial hyperplasia of the renal pelvis, were also observed in female rats. No organ weight, gross, or microscopic lesions indicative of systemic toxicity were observed in female rats exposed to doses of 300 or 600 mg/kg/day. Developmental toxicity of glycolic acid in rats was assessed during days 7–21 of gestation. Mated female rats were grouped and administered up to 600 mg/kg daily by gavage. Significant maternal toxicity was observed at 600 mg/kg. Significant developmental toxicity was also observed at 600 mg/kg. The mean fetal weight was significantly reduced, and the incidence of skeletal (rib, vertebra, and sternum) malformations and variations was also significantly reduced. No genotoxicity of glycolic acid was found in either activated or inactivated Ames tests using Salmonella typhimurium TA98, TA100, TA1535, TA1537, and TA1538. Ecotoxicity studies: Green algae were exposed to glycolic acid for 72 hours. After the exposure period, a recovery test was conducted on the control group and the experimental concentration group with a cell count inhibition rate of 50% or higher, followed by an additional 144 hours of exposure in nutrient medium. The results showed that glycolic acid inhibited the growth rate and biomass of green algae. Gizzard gnats were exposed to glycolic acid under static conditions for 96 hours. All fish died within 24 hours. Large clams were exposed to glycolic acid under static conditions for 48 hours. No sublethal effects were observed in surviving large clams. The toxicity of glycolic acid stems from its metabolism to oxalic acid. Glycolic acid and oxalic acid, along with excess lactic acid, are the causes of anion gap metabolic acidosis. Oxalic acid readily precipitates with calcium to form insoluble calcium oxalate crystals. Extensive deposition of calcium oxalate crystals and the toxic effects of glycolic acid can lead to tissue damage. (A612, A613)

---

Effects during pregnancy and lactation
◉ Overview of use during lactation
There is currently no clinical information regarding the skin use of glycolic acid (hydroxyacetic acid) during lactation. Because it is unlikely to be significantly absorbed or present in breast milk, its use during lactation is considered safe. Avoid application to body parts that may come into direct contact with the infant's skin or to areas where the infant may ingest the drug through licking.
◉ Effects on lactating women and infants
As of the revision date, no relevant published information was found.
◉ Effects on lactation and breast milk
As of the revision date, no relevant published information was found.

---

Toxicity Data
LC50 (Rat) = 7.1 mg/m3/4 hours
LD50: 1950 mg/kg (oral, rat) (A655)
LD50: 1000 mg/kg (intravenous, cat) (A730)
LC50: 7.7-14 mg/L, 4 hours (inhalation, rat) (A730)

---

Interactions
The effects of 0.35 to 0.8 mmol/kg glycolic acid and 1.0 to 4.4 mmol/kg sodium glycolate on cyclopropane-epinephrine-induced arrhythmias were investigated. Canines were used in this study. In 13 dogs, doses of glycolic acid ranging from 0.35 to 0.5 mmol/kg prolonged the duration of arrhythmias, while doses >0.5 mmol/kg alleviated or completely eliminated arrhythmias in 11 dogs. At higher doses, many dogs experienced depression. Sodium glycolate is far less effective than glycolic acid in reducing cardiac arrhythmias, requiring a dose of 3 mmol/kg, and its effects are short-lived. This study aimed to determine whether short-term topical application of glycolic acid (a typical alpha-hydroxy acid (AHA)) enhances the damaging effects of ultraviolet radiation. The study also examined the duration of the effects of AHA on skin's UV sensitivity. In a randomized, double-blind study, 29 Caucasian subjects received either 10% glycolic acid (pH 3.5) or a placebo once daily, six days a week. After four weeks, each treated area was exposed to 1.5 times the minimum erythema dose (MED) of ultraviolet radiation, which was measured on previously untreated skin. Samples were collected from the first group (n = 16) for counting sunburn cells (SBCs), while cyclobutylpyrimidine dimers (CPDs) in DNA were measured in the second group (n = 13). The minimum erythema dose (MED) was also measured at each site in the first group. One week after discontinuation of AHA, sunburned cells and MED in the first group of subjects were reassessed. ... Glycolic acid led to increased sensitivity to UV radiation, manifested as increased SBC induction and decreased MED. Cyclobutylpyrimidine dimer levels were elevated, but not statistically significant. One week after treatment cessation, there were no significant differences in SBC or MED...
Hairless mice were exposed to UVB three times a week for 10 weeks. During the 10 weeks following irradiation, mice were topically treated five times a week with retinoic acid (0.05%), glycolic acid (10%), benzalkonium chloride (1.0%), sodium lauryl sulfate (5%), croton oil (5%), and a water-propylene glycol solvent... Retinoic acid-treated skin showed increased collagen and type III procollagen content, while skin treated with stimulants and exfoliants was similar to the solvent control group.
Glycolic acid is an inhibitor that antagonizes the convulsive effects of strychnine in the feline spinal cord.
For more complete data on interactions of glycolic acid (11 in total), please visit the HSDB record page.

---

Non-human toxicity values
Oral LD50 in rats: 4240 mg/kg body weight
Oral LD50 in rats: 1600-3200 mg/kg body weight (bw)
Oral LD50 in rats: 1,950 mg/kg
Oral LD50 in guinea pigs: 1,920 mg/kg
For more complete data on non-human toxicity values of glycolic acid (17 types in total), please visit the HSDB record page.

[1]. Usuki A, et al. The inhibitory effect of glycolic acid and lactic acid on melanin synthesis in melanoma cells. Exp Dermatol. 2003;12 Suppl 2:43-50

Glycolic acid is a 2-hydroxy monocarboxylic acid, a methyl hydroxylated product of acetic acid. It is both a metabolite and a keratolytic agent. It is a 2-hydroxy monocarboxylic acid and a primary alcohol. Functionally, it is related to acetic acid. It is the conjugate acid of glycolate. Glycolic acid is found in or produced by Escherichia coli (K12 strain, MG1655 strain). Glycolic acid is found in or produced by Escherichia coli (K12 strain, MG1655 strain). Glycolic acid has been reported in Aspen, Rubia cordifolia, and other organisms with relevant data. Glycolic acid (or glycolic acid) is the smallest α-hydroxy acid (AHA). This colorless, odorless, hygroscopic crystalline solid is highly soluble in water. Due to its excellent skin penetration, glycolic acid is widely used in skincare products, most commonly as a chemical peeling agent. It can reduce wrinkles, acne scars, and pigmentation, and improve many other skin problems, including actinic keratosis, hyperkeratosis, and seborrheic keratosis. Upon application, glycolic acid reacts with the upper epidermis, weakening the binding force of lipids connecting dead skin cells. This causes the epidermis to dissolve, exposing the underlying skin. (L1909)
See also: glycolic acid; salicylic acid; sulfur (ingredient); glycolic acid; salicylic acid (ingredient); glycerin; glycolic acid (ingredient)...see more...

---

Mechanism of Action
The toxicity of ethylene glycol stems from its metabolism into glycolic acid and other toxic metabolites. The accumulation of glycolic acid and the elimination kinetics of ethylene glycol and its metabolites are not fully understood; therefore, studies were conducted using male Sprague-Dawley rats and mixed-breed dogs as models. Ethylene glycol was administered to rats and dogs by gavage, and they were placed in metabolic cages, with urine and blood samples collected periodically. Peak plasma concentrations of ethylene glycol occurred 2 hours after administration, while peak plasma concentrations of glycolic acid occurred 4–6 hours after administration. Ethylene glycol was eliminated slightly faster in rats, with a half-life of 1.7 hours, compared to 3.4 hours in dogs. Although the accumulation pattern of glycolic acid was similar to that in dogs, peak plasma concentrations of glycolic acid were higher in rats. The simultaneous disappearance of glycolic acid from plasma along with ethylene glycol indicates that the elimination rate of its metabolite was slower than that of ethylene glycol. Ethylene glycol was primarily excreted by the kidneys, accounting for approximately 20-30% of the administered dose. Glycolic acid was excreted by the kidneys at approximately 5% of the administered dose. Compared to control rats, ethylene glycol immediately caused a transient diuretic effect. In both rats and dogs, these doses of ethylene glycol (1-2 g/kg) caused only mild clinical reactions (mild acidosis, without sedation). These results indicate that the toxicokinetics of ethylene glycol and glycolic acid are similar in both animal groups. This study also investigated the effects of 0.35–0.8 mmol/kg glycolic acid and 1.0–4.4 mmol/kg sodium glycolate on cyclopropane-adrenaline-induced arrhythmias using a canine model. In 13 dogs tested, glycolic acid at doses of 0.35 to 0.5 mmol/kg prolonged the duration of arrhythmias, while doses >0.5 mmol/kg reduced or completely eliminated arrhythmias in 11 dogs. At higher doses, many dogs developed depression. Sodium glycolate was far less effective than glycolic acid in reducing arrhythmias, requiring a dose of 3 mmol/kg, and its effects were short-lived.

---

Therapeutic Uses
Keratinizing Agent
Glycolic acid belongs to the alpha-hydroxy acid (AHA) family and has been used in skin regeneration therapy for centuries. In recent years, it has proven to be a versatile exfoliant and is now widely used to treat a variety of defects in the epidermis and papillary dermis, at concentrations ranging from 20% to 70%, depending on the condition being treated. Chemical peels can be performed on almost anyone of any skin color and type, and on almost any part of the body…
Dermatologists have used glycolic acid to treat skin diseases for many years, and it is also an ingredient in many over-the-counter personal care products. No systemic toxicity has been found due to these uses. Chemical peels, also known as chemical ablations or skin peels, are designed to improve the appearance of the skin by reducing wrinkles and photo-aged skin characteristics caused by aging. While deep (phenolic) peels are most effective, medium-depth peels can also achieve good results without the dangerous side effects of deep peels. Medium-depth peels are performed alone with 35-50% trichloroacetic acid (TCA), or in combination with 35% TCA, Jessner's solution, 70% glycolic acid, and solid carbon dioxide (CO₂)... For more complete data on the therapeutic uses of glycolic acid (27 in total), please visit the HSDB record page.

---

Drug Warning
The FDA has considered evidence suggesting that topical cosmetics containing alpha-hydroxy acids (AHAs) may increase skin sensitivity to sunlight, which persists for up to one week after discontinuation and may increase the risk of sunburn. As a temporary measure, while the FDA continues to review AHA data to address concerns about its potential to increase skin sensitivity to sunlight, the FDA recommends that all cosmetics containing AHAs and applied topically to the skin or mucous membranes include the following information on their labeling. The information in the AHA labeling statement is consistent with the FDA's current philosophy on sun protection. Sunburn Warning: This product contains alpha-hydroxy acids (AHAs), which may increase skin sensitivity to sunlight, particularly the likelihood of sunburn. Use sunscreen, wear protective clothing, and limit sun exposure during and for one week after using this product. /Alpha-Hydroxy Acids/
Between 1989 and 1996, FDA headquarters and regional offices received and evaluated consumer reports of adverse reactions to products containing alpha-hydroxy acids (AHAs). Typical adverse reactions include “severe redness, swelling (especially around the eyes), burning sensation, blistering, bleeding, scarring, rash, itching, contact dermatitis, skin discoloration (reportedly permanent), and adverse neurological reactions.” Some individuals who submitted adverse reaction reports had consulted a physician; at least one adverse reaction report involved professional medication use, and at least one involved a product prescribed by a dermatologist. The FDA filing states, “In addition to consumer-reported adverse reactions, we have received letters from dermatologists who are treating patients injured by using these (AHA-containing) products.” /Alpha-hydroxy acids/

C2H4O3

76.05

76.016

79-14-1

Glycolic acid-d2;75502-10-2;Glycolic acid-13C2;111389-68-5

757

Colorless, translucent solid
Solid glycolic acid forms colorless, monoclinic, prismatic crystals.
Orthorhombic needles from water; leaves from diethyl ether

1.4±0.1 g/cm3

265.6±13.0 °C at 760 mmHg

75-80 °C(lit.)

128.7±16.3 °C

0.0±1.2 mmHg at 25°C

1.450

-1.05

2

3

1

5

40.2

0

O=C(CO)O

AEMRFAOFKBGASW-UHFFFAOYSA-N

InChI=1S/C2H4O3/c3-1-2(4)5/h3H,1H2,(H,4,5)

2-hydroxyacetic acid

Glycolic acid; Hydroxyethanoic acid; Hydroxyacetic acid

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

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

H2O : ~100 mg/mL (~1314.92 mM)
DMSO : ≥ 100 mg/mL (~1314.92 mM)

Solubility in Formulation 1: ≥ 2.5 mg/mL (32.87 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.

---

Solubility in Formulation 2: ≥ 2.5 mg/mL (32.87 mM) (saturation unknown) in 10% DMSO + 90% (20% SBE-β-CD in 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 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.

---

View More

Solubility in Formulation 3: ≥ 2.5 mg/mL (32.87 mM) (saturation unknown) in 10% DMSO + 90% Corn Oil (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 900 μL of corn oil and mix evenly.

---

Solubility in Formulation 4: 100 mg/mL (1314.92 mM) in PBS (add these co-solvents sequentially from left to right, and one by one), clear solution; with ultrasonication.

---

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