Glycopeptide

In animal modeling, vancomycin can be used to create kidney injury models. To reduce infusion-related side effects, vancomycin is infused intravenously for a minimum of one hour. Vancomycin has a β-elimination half-life of 6–12 hours and an α-distribution phase of 30 min to 1 h in subjects with normal creatinine clearance. 0.4–1 L/kg is the distribution volume. Vancomycin can bind to proteins 10%–50% of the time. Vancomycin's total activity is influenced by a number of factors, including its tissue distribution, inoculum size, and effects on protein binding[1]. Treatment with vancomycin for infected mice is linked to better scores in histopathology, clinical manifestations, and diarrhea[3].

Vancomycin is administered intravenously, with a standard infusion time of at least 1 h, to minimize infusion-related adverse effects. Subjects with normal creatinine clearance, vancomycin has an α-distribution phase of 30 min to 1 h and a β-elimination half-life of 6-12 h. The volume of distribution is 0.4–1 L/kg. The binding of vancomycin to protein ranges from 10% to 50%. Factors that affect the overall activity of vancomycin include its tissue distribution, inoculum size, and protein-binding effects. Vancomycin treatment of infected mice is associated with improved clinical, diarrhea, and histopathology scores and survival during treatment.

Vancomycin is a unique glycopeptide structurally unrelated to any currently available antibiotic. It also has a unique mode of action inhibiting the second stage of cell wall synthesis of susceptible bacteria. There is also evidence that vancomycin alters the permeability of the cell membrane and selectively inhibits ribonucleic acid synthesis. Induction of bacterial L-phase variants from susceptible organisms with vancomycin is extremely difficult, and such variants are unstable. Stable L-phase variants induced by other agents are susceptible to vancomycin. Vancomycin is active against a large number of species of Gram-positive bacteria, such as Staphylococcus aureus (including methicillin-resistant strains), Staph. epidermidis (including multiple-resistant strains), Streptococcus pneumoniae (including multiple-resistant strains), Str. pyogenes, Str. agalactiae, Str. bovis, Str. mutans, viridans streptococci, enterococci, Clostridium species, diphtheroids, Listeria monocytogenes, Actinomyces species and Lactobacillus species. There has been no increase in resistance to vancomycin during the past three decades. Enhancement of antimicrobial activity has been demonstrated with the combination of vancomycin and an aminoglycoside against Staph. aureus, Str. bovis, enterococci and viridans streptococci. The combination of vancomycin and rifampicin are antagonistic to most strains of Staph. aureus, though indifference and occasionally synergism have been shown, but is synergistic against strains of Staph. epidermidis. It shows indifference against enterococci. Vancomycin and fusidic acid are indifferent against Staph. aureus [2].

C. difficile toxin assay. C. difficile toxins A and B were detected using a modified protocol for the Tech Lab Toxin A/B II ELISA kit. Each stool sample was weighed and the amount of diluent per sample was normalized to provide the same stool mass-to-diluent ratio for each sample. The diluent-sample mixtures were homogenized by grinding and vortexing, and 1:10, 1:100, and 1:1,000 serial dilutions were made of the sample. A total of 150 μl of the 1:1,000 dilution of each sample was added to a precoated well provided in the kit. A negative control consisted of 150 μl of diluent, and a positive control consisted of 135 μl of diluent plus 3 drops of the positive control toxin A-B mixture provided in the kit. One drop of conjugate was added to each well, and the plate was incubated at 37°C for 50 min. Each well was washed three times with 150 μl of a 1× dilution of the wash buffer provided in the kit. Two drops of substrate were added to each well. After 10 min, 1 drop of stop solution was added to each well. The plate was allowed to sit for 2 min before being read in an ELISA reader [3].

Mice: In one series of studies, infected mice are given either vancomycin (20 mg/kg) daily for five or ten days and monitored for fifteen days after infection, or vancomycin (50 mg/kg) daily for one, two, three, or five days and monitored for twenty-one days after infection[3].

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Murine model of C. difficile infection and treatment.[3]
The infection model is a modification of the published protocol of Chen et al. This protocol has been approved by the Center for Comparative Medicine at University of Virginia. C57BL/6 mice, male, 8 weeks old, were used. From 6 to 4 days prior to infection, mice were given an antibiotic cocktail containing vancomycin (0.0045 mg/g), colistin (0.0042 mg/g), gentamicin (0.0035 mg/g), and metronidazole (0.0215 mg/g) in drinking water. One day prior to infection, clindamycin (32 mg/kg of body weight) was injected subcutaneously. The mice were divided into the following groups: control uninfected, control infected, infected and treated with vancomycin (20 mg/kg), and infected and treated with comparator drugs—nitazoxanide, fidaxomicin, and metronidazole (all drugs given at 20 mg/kg/day). Food and water were allowed ad libitum. Although each mouse or treatment group was housed in a separate cage, all mice were housed in the same pod of the vivarium. Infection was performed with VPI 10463 (ATCC) as an inoculum of 104 or 105 administered by oral gavage. This strain produces both C. difficile toxins A (TcdA) and B (TcdB). One day postinfection, treated mice were given either vancomycin or nitazoxanide at 20 mg/kg each by oral gavage daily for 5 days and monitored for either 1 or 2 weeks postinfection. One set of experiments was performed in which infected mice were treated with vancomycin (50 mg/kg) daily for 1, 2, 3, or 5 days and were observed for 21 days postinfection or with vancomycin (20 mg/kg) daily for either 5 or 10 days and monitoring for 15 days postinfection. In a separate experiment, mice given a preinfection antibiotic regimen described above were treated with either vancomycin, fidaxomicin, or metronidazole at 20 mg/kg/day for 5 days and infected another 5 days later. Except when indicated, all comparator drugs were administered using the same dosage (20 mg/kg/day for 5 days) to equally compare efficacies, outcomes, and effects on selected gut floras between treatment groups as previously described. From another study, a group of control mice was given vancomycin but was not infected. A clinical scoring system was developed on the basis of weight loss, diarrhea, activity level, and appearance of eyes and hair (each parameter scored from 0 to 3, where 0 is normal and 3 is the worst; maximum score of 20). Stool specimens were collected daily. Diarrhea was scored as follows: 1 for soft or color change (yellow), 2 for wet tail or mucoid, and 3 for liquid or no stool (ileus). Mice judged moribund by the clinical score (score of >14) at any day and all surviving mice at the end of the experiment were sacrificed, and intestinal tissues and cecal contents were collected as described below. A separate set of experiments was performed for harvesting cecal contents for clostridial bacterial and toxin burdens at days 3, 6, 9, and 12 to 13 postinfection to follow changes at different time points of the study.
Histopathology. Upon euthanasia, cecal and colonic tissues were fixed in 10% zinc formalin overnight and then placed in 10% ethanol before being sent for paraffin embedding and hematoxylin and eosin (H&E) staining at the University of Virginia Histology Research Core. Histopathologic scoring was performed coded (C.A.W. and M.S.R.). H&E-stained tissues were scored for mucosal disruption, mucosal hypertrophy, inflammation, vascular congestion and exudates, and submucosal edema (each parameter was graded from 0 to 3, with 0 as normal and 3 worst; maximum score of 15) as we previously described in detail.

Absorption, Distribution and Excretion
Poorly absorbed from gastrointestinal tract, however systemic absorption (up to 60%) may occur following intraperitoneal administration.
In the first 24 hours, about 75-80% of an administered dose of vancomycin is excreted in urine by glomerular filtration.
The volume of distribution, as discussed in the literature, varies between 0.4-1 L/kg.
The mean plasma clearance of vancomycin is about 0.058 L/kg/h.
Vancomycin hydrochloride is not appreciably absorbed from the GI tract in most patients and must be given parenterally for the treatment of systemic infections. Oral bioavailability usually is less than 5%; however, limited data suggest that clinically important serum concentrations of the drug may result following enteral or oral administration of vancomycin in some patients with colitis and/or in those with renal impairment.
In adults with normal renal function who received multiple 1 g doses of vancomycin (15 mg/kg) given by IV infusion over 1 hour, mean plasma concentrations immediately after completion of the infusion are approximately 63 ug/mL and mean plasma concentrations 2 and 11 hours later are approximately 23 or 8 ug/mL, respectively. When multiple 500-mg doses are given by IV infusion over 30 minutes, mean plasma concentrations are about 49 ug/mL immediately following the infusion and about 10 ug/mL 6 hours after infusion.
Vancomycin is distributed into milk following IV administration. Systemic absorption of oral vancomycin is very low and it is not known whether the drug distributes into human milk following oral administration.
Vancomycin readily crosses the placenta and is distributed into cord blood.
Vancomycin is approximately 55% serum protein bound as measured by ultrafiltration at vancomycin serum concentrations of 10 to 100 mcg/mL. After IV administration of vancomycin hydrochloride, inhibitory concentrations are present in pleural, pericardial, ascitic, and synovial fluids; in urine; in peritoneal dialysis fluid; and in atrial appendage tissue. Vancomycin hydrochloride does not readily diffuse across normal meninges into the spinal fluid; but, when the meninges are inflamed, penetration into the spinal fluid occurs.

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Metabolism / Metabolites
Since almost 75-80% of the drug is excreted unchanged in the urine after the first 24 hours following administration, there is seemingly no apparent metabolism of the drug. The concentration of vancomycin in the liver tissue and bile 24 hours after administration has also been reported at or below detection limits as well.
Free toxin may be removed by opsonization via the reticuloendothelial system (primarily the liver and kidneys) or it may be degraded through cellular internalization via the lysosomes. Lysosomes are membrane-enclosed organelles that contain an array of digestive enzymes, including several proteases.
Route of Elimination: In the first 24 hours, about 75% of an administered dose of vancomycin is excreted in urine by glomerular filtration.
Half Life: Half-life in normal renal patients is approximately 6 hours (range 4 to 11 hours). In the first 24 hours, about 75% of an administered dose of vancomycin is excreted in urine by glomerular filtration. In anephric patients, the average half-life of elimination is 7.5 days.

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Biological Half-Life
Half-life in normal renal patients is approximately 6 hours (range 4 to 11 hours). In anephric patients, the average half-life of elimination is 7.5 days.
The mean elimination half-life of vancomycin from plasma is 4 to 6 hours in subjects with normal renal function.
In anephric patients, the average half-life of elimination is 7.5 days.

Toxicity Summary
The bactericidal action of vancomycin results primarily from inhibition of cell-wall biosynthesis. Specifically, vancomycin prevents incorporation of N-acetylmuramic acid (NAM)- and N-acetylglucosamine (NAG)-peptide subunits from being incorporated into the peptidoglycan matrix; which forms the major structural component of Gram-positive cell walls. The large hydrophilic molecule is able to form hydrogen bond interactions with the terminal D-alanyl-D-alanine moieties of the NAM/NAG-peptides. Normally this is a five-point interaction. This binding of vancomycin to the D-Ala-D-Ala prevents the incorporation of the NAM/NAG-peptide subunits into the peptidoglycan matrix. In addition, vancomycin alters bacterial-cell-membrane permeability and RNA synthesis. There is no cross-resistance between vancomycin and other antibiotics. Vancomycin is not active in vitro against gram-negative bacilli, mycobacteria, or fungi.

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Toxicity Data
LD50: 5000 mg/kg (Oral, Mouse) (A308)
LD50: 319 mg/kg (Intravenous, Rat) (A308)
LD50: 400 mg/kg (Intravenous, Mouse) (A308)

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Interactions
Concomitant use of vancomycin and anesthetic agents has been associated with anaphylactoid reactions and an increased frequency of infusion reactions (e.g., hypotension, flushing, erythema, urticaria, pruritus). Erythema and histamine-like flushing has occurred in pediatric patients receiving vancomycin and anesthetic agents concomitantly. The risk of infusion-related adverse effects may be minimized if vancomycin is given as a 1-hour IV infusion prior to induction of anesthesia.
In vitro, the antibacterial effects of vancomycin and aminoglycosides are synergistic against many strains of Staphylococcus aureus, nonenterococcal group D streptococci (Streptococcus bovis), enterococci (Enterococcus faecalis), and viridans streptococci. However, concomitant use of vancomycin and aminoglycosides is associated with an increased risk of ototoxicity and/or nephrotoxicity.
Because of the possibility of additive toxicities, the concurrent or sequential systemic or topical use of other ototoxic and/or nephrotoxic drugs (e.g., aminoglycosides, amphotericin B, bacitracin, cisplatin, colistin, polymyxin B) and vancomycin requires careful serial monitoring of renal and auditory function. These drugs should be used with caution in patients receiving vancomycin therapy.
Renal failure developed after a prolonged course of vancomycin therapy in 2 patients who were receiving tenofovir disoproxil fumarate as part of an antiretroviral regimen. Tenofovir has been implicated in the development of Fanconi syndrome and renal insufficiency because of its effects on the proximal renal tubule. Vancomycin nephrotoxicity is infrequent but may result from coadministration with a nephrotoxic agent. Clinicians should be aware that tenofovir may raise the risk of renal failure during prolonged administration of vancomycin.
For more Interactions (Complete) data for Vancomycin (6 total), please visit the HSDB record page.

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Non-Human Toxicity Values
LD50 Mouse oral 5000 mg/kg /Monohydrochloride/
LD50 Mouse ip 1734 mg/kg
LD50 Mouse iv 430 mg/kg
LD50 Mouse sc 5000 mg/kg
LD50 Rat iv 319 mg/kg

[1]. The pharmacokinetic and pharmacodynamic properties of vancomycin. Clin Infect Dis. 2006 Jan 1;42 Suppl 1:S35-9.

[2]. Mode of action and in-vitro activity of vancomycin. J Antimicrob Chemother. 1984 Dec;14 Suppl D:7-18.

[3]. Vancomycin treatment's association with delayed intestinal tissue injury, clostridial overgrowth, and recurrence of Clostridium difficile infection in mice. Antimicrob Agents Chemother. 2013 Feb;57(2):689-96.

Therapeutic Uses
Antibiotics, Glycopeptide
Vancomycin hydrochloride is indicated for the treatment of serious or severe infections caused by susceptible strains of methicillin-resistant (beta-lactam-resistant) staphylococci. It is indicated for penicillin-allergic patients, for patients who cannot receive or who have failed to respond to other drugs, including the penicillins or cephalosporins, and for infections caused by vancomycin-susceptible organisms that are resistant to other antimicrobial drugs. Vancomycin hydrochloride is indicated for initial therapy when methicillin-resistant staphylococci are suspected, but after susceptibility data are available, therapy should be adjusted accordingly. /Included in US product label/
Vancomycin hydrochloride is effective in the treatment of staphylococcal endocarditis. Its effectiveness has been documented in other infections due to staphylococci, including septicemia, bone infections, lower respiratory tract infections, skin and skin-structure infections. When staphylococcal infections are localized and purulent, antibiotics are used as adjuncts to appropriate surgical measures. /Included in US product label/
The parenteral form of vancomycin hydrochloride may be administered orally for treatment of antibiotic-associated pseudomembranous colitis produced by C. difficile and for staphylococcal enterocolitis. Parenteral administration of vancomycin hydrochloride alone is of unproven benefit for these indications. Vancomycin hydrochloride is not effective by the oral route for other types of infection. /Included in US product label/
For more Therapeutic Uses (Complete) data for Vancomycin (12 total), please visit the HSDB record page.

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Drug Warnings
Ototoxicity and nephrotoxicity are the most serious adverse effects of parenteral vancomycin therapy. The incidences of ototoxicity and nephrotoxicity have not been well established, but clinical experience to date suggests that these adverse effects occur relatively infrequently. Ototoxicity and nephrotoxicity are most likely to occur in patients with renal impairment, patients receiving IV vancomycin in high doses or for prolonged periods, or patients receiving other ototoxic and/or nephrotoxic drugs. Although ototoxicity and nephrotoxicity have been associated with serum or blood vancomycin concentrations of 80-100 ug/mL, these reactions have occurred with concentrations as low as 25 ug/mL. Correlations between serum vancomycin concentrations and ototoxicity and nephrotoxicity still remain to be clarified. Ototoxicity may be transient or permanent. Vancomycin may cause damage to the auditory branch of the eighth cranial nerve and permanent deafness has occurred. Vertigo, dizziness, and tinnitus have been reported rarely. Tinnitus may precede the onset of deafness and necessitates discontinuance of the drug. Deafness may progress despite cessation of vancomycin therapy. Vancomycin-induced nephrotoxicity may be manifested by transient elevations in BUN or serum creatinine concentrations, and the presence of hyaline and granular casts and albumin in the urine. Fatal uremia has occurred. Rarely, the drug has been associated with acute interstitial nephritis.
Rapid IV administration of vancomycin has resulted in a hypotensive reaction frequently referred to as the "red-man syndrome" or "red-neck syndrome". The reaction is characterized by a sudden decrease in blood pressure which can be severe and may be accompanied by flushing and/or a maculopapular or erythematous rash on the face, neck, chest, and upper extremities; the latter manifestations may also occur in the absence of hypotension. Wheezing, dyspnea, angioedema, urticaria, and pruritus may also occur. Rarely, cardiac arrest or seizures have occurred. Vancomycin-induced hypotension appears to result from a negative inotropic and vasodilating action produced in part by a release of histamine, which is directly related to the rate of infusion; the release of histamine also appears to be responsible for the usual manifestations (e.g., erythema, rash, pruritus) of the "red" characterization. The reaction usually begins a few minutes after the vancomycin infusion is started, but may not occur until after the infusion is completed, and usually resolves spontaneously over one to several hours after discontinuance of the infusion. If the hypotensive reaction is severe, the use of antihistamines, corticosteroids, or IV fluids may be necessary. The hypotensive reaction is related to the rate of infusion of vancomycin and has been reported most frequently when the drug was administered over a period of 10 minutes or less; however, the reaction may also occur rarely when the drug is infused over a period of 1 hour or longer. To minimize the risk of a hypotensive reaction, vancomycin should be infused over a period of at least 1 hour and the patient's blood pressure should be monitored during the infusion. In patients who have had the reaction, subsequent doses of vancomycin can usually be given without adverse effect if administered at a slow rate (e.g., over several hours). Pretreatment with antihistamines may be of benefit. If attempts to minimize the reaction fail, use of another anti-infective agent may be necessary. The reaction reportedly has occurred in more than 50% of healthy individuals given vancomycin but less frequently when the drug is used therapeutically.
Urticaria, exfoliative dermatitis, macular rashes, eosinophilia, vasculitis, a shock-like state, transient anaphylaxis, and, occasionally, vascular collapse have been reported in patients receiving vancomycin. The drug also has been associated with Stevens-Johnson syndrome in at least one patient.
A throbbing pain in the muscles of the back and neck has been reported with vancomycin and can usually be minimized or avoided by slower administration of the drug. In patients undergoing continuous ambulatory peritoneal dialysis (CAPD), intraperitoneal administration of vancomycin has been associated with chemical peritonitis, a syndrome consisting of a cloudy dialysate, which may be accompanied by abdominal pain and fever. Chemical peritonitis usually disappears shortly after discontinuance of intraperitoneal vancomycin. Other adverse effects of vancomycin include chills and fever. Priapism after a second IV dose of vancomycin, with recurrence on inadvertent rechallenge, occurred in a 37-year-old man with severe underlying diabetes mellitus; bilateral phlebotomy of the corpus cavernosum resulted in resolution of the priapism.
For more Drug Warnings (Complete) data for Vancomycin (22 total), please visit the HSDB record page.

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Pharmacodynamics
Vancomycin is a branched tricyclic glycosylated nonribosomal peptide often reserved as the "drug of last resort", used only after treatment with other antibiotics has failed. Vancomycin has been shown to be active against most strains of the following microorganisms, both in vitro and in clinical infections: Listeria monocytogenes, Streptococcus pyogenes, Streptococcus pneumoniae (including penicillin-resistant strains), Streptococcus agalactiae, Actinomyces species, and Lactobacillus species. The combination of vancomycin and an aminoglycoside acts synergistically in vitro against many strains of Staphylococcus aureus, Streptococcus bovis, enterococci, and the viridans group streptococci.

C66H75CL2N9O24

1449.25

1447.43

1404-90-6

Vancomycin hydrochloride;1404-93-9

14969

White to off-white solid powder

1.65 g/cm3

4.734

19

26

13

101

2960

18

ClC1C([H])=C2C([H])=C([H])C=1OC1=C([H])C3[C@]([H])(C(N([H])[C@@]4([H])C(N([H])[C@]([H])(C(N([H])[C@]([H])(C(=O)O[H])C5C([H])=C(C([H])=C(C=5C5=C(C([H])=C([H])C4=C5[H])O[H])O[H])O[H])=O)[C@@]([H])(C4C([H])=C([H])C(=C(C=4[H])Cl)OC(C=3[H])=C1O[C@@]1([H])[C@@]([H])([C@]([H])([C@@]([H])([C@@]([H])(C([H])([H])O[H])O1)O[H])O[H])O[C@@]1([H])C([H])([H])[C@@](C([H])([H])[H])([C@@]([H])([C@]([H])(C([H])([H])[H])O1)O[H])N([H])[H])O[H])=O)=O)N([H])C([C@]([H])(C([H])([H])C(N([H])[H])=O)N([H])C([C@@]([H])([C@]2([H])O[H])N([H])C([C@@]([H])(C([H])([H])C([H])(C([H])([H])[H])C([H])([H])[H])N([H])C([H])([H])[H])=O)=O)=O

MYPYJXKWCTUITO-LYRMYLQWSA-N

InChI=1S/C66H75Cl2N9O24/c1-23(2)12-34(71-5)58(88)76-49-51(83)26-7-10-38(32(67)14-26)97-40-16-28-17-41(55(40)101-65-56(54(86)53(85)42(22-78)99-65)100-44-21-66(4,70)57(87)24(3)96-44)98-39-11-8-27(15-33(39)68)52(84)50-63(93)75-48(64(94)95)31-18-29(79)19-37(81)45(31)30-13-25(6-9-36(30)80)46(60(90)77-50)74-61(91)47(28)73-59(89)35(20-43(69)82)72-62(49)92/h6-11,13-19,23-24,34-35,42,44,46-54,56-57,65,71,78-81,83-87H,12,20-22,70H2,1-5H3,(H2,69,82)(H,72,92)(H,73,89)(H,74,91)(H,75,93)(H,76,88)(H,77,90)(H,94,95)/t24-,34+,35-,42+,44-,46+,47+,48-,49+,50-,51+,52+,53+,54-,56+,57+,65-,66-/m0/s1

(1S,2R,18R,19R,22S,25R,28R,40S)-48-[(2S,3R,4S,5S,6R)-3-[(2S,4S,5S,6S)-4-amino-5-hydroxy-4,6-dimethyloxan-2-yl]oxy-4,5-dihydroxy-6-(hydroxymethyl)oxan-2-yl]oxy-22-(2-amino-2-oxoethyl)-5,15-dichloro-2,18,32,35,37-pentahydroxy-19-[[(2R)-4-methyl-2-(methylamino)pentanoyl]amino]-20,23,26,42,44-pentaoxo-7,13-dioxa-21,24,27,41,43-pentazaoctacyclo[26.14.2.23,6.214,17.18,12.129,33.010,25.034,39]pentaconta-3,5,8(48),9,11,14,16,29(45),30,32,34(39),35,37,46,49-pentadecaene-40-carboxylic acid

Vancocin;Vancoled; Vancomicina; Vancomycine; Vancomycinum; VANCOR

3004209090

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 : ~125 mg/mL (~86.25 mM)

Solubility in Formulation 1: ≥ 4.17 mg/mL (2.88 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 41.7 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: ≥ 4.17 mg/mL (2.88 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 41.7 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.)