In order to study bacterial infections in burns, silver sulfadiazine (AgSD) is used topically[2].

Absorption, Distribution and Excretion
Extremely poor skin penetration. Absorption problems only occur when used for large-area burns. Metabolism/Metabolites Sulfonamides undergo two degradation pathways: one is the N-acetylation pathway, which is genetically determined and saturable; the other is the cytochrome P450 pathway, which produces toxic hydroxylamine metabolites that require glutathione for detoxification. (A2885)

Toxicity Summary
Studies using radioactive microparticle-based silver sulfadiazine, electron microscopy, and biochemical techniques have shown that the mechanism of action of silver sulfadiazine against bacteria differs from that of silver nitrate and sodium sulfadiazine. Silver sulfadiazine acts only on the cell membrane and cell wall, thereby producing a bactericidal effect. Its specific mechanism of action is not yet fully understood, but the effectiveness of silver sulfadiazine may stem from synergistic effects or the combined action of its components. Silver is a biocidal agent that can bind to a variety of targets. Silver ions can bind to nucleophilic amino acids, as well as thiol, amino, imidazole, phosphate, and carboxyl groups in proteins, leading to protein denaturation and enzyme inhibition. Silver can bind to cell surface membranes and proteins, causing membrane proton leakage and ultimately cell death. Sulfadiazine is a competitive inhibitor of bacterial para-aminobenzoic acid (PABA), a substrate of dihydropteroate synthase. This inhibitory response is essential for the synthesis of folic acid in these organisms.

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Toxicity Data
LD50: 10001 mg/kg (oral, rat)

[1]. Strydom SJ, et al. Poly(amidoamine) dendrimer-mediated synthesis and stabilization of silver sulfonamide nanoparticles with increased antibacterial activity. Nanomedicine. 2013;9(1):85-93.
[2]. Munhoz DR, et al. Alginate films functionalized with silver sulfadiazine-loaded [Mg-Al] layered double hydroxide as antimicrobial wound dressing. Int J Biol Macromol. 2019;141:504-510.

Silver sulfadiazine (1+) is a silver salt belonging to the sulfonamide class of compounds and is also a pyrimidine drug. It possesses antibacterial and antimicrobial activity. It contains a sulfadiazine group. Silver sulfadiazine is a sulfonamide derivative topical antibacterial agent, primarily used for second- and third-degree burns. Silver sulfadiazine is a sulfonamide antibacterial agent. Silver sulfadiazine is a sulfonamide topical medication with antibacterial and antifungal activity. The mechanism of action of silver sulfadiazine may be the combined effect of silver and sulfadiazine. When this drug interacts with body fluids containing sodium chloride, silver ions are slowly and continuously released into the wound area. Ionized silver atoms catalyze the formation of disulfide bonds, leading to changes in protein structure and inactivation of thiol-containing enzymes; silver ions may also intercalate into DNA, thereby interfering with bacterial replication and transcription. As a competitive inhibitor of para-aminobenzoic acid (PABA), sulfadiazine inhibits bacterial dihydropteroate synthase, thereby disrupting folic acid metabolism and ultimately affecting DNA synthesis. Silver sulfadiazine is only present in individuals who have used or ingested the drug. It is a sulfonamide derivative topical antibacterial agent primarily used to treat second- and third-degree burns. [Wikipedia] Studies using radioactive microparticle-based silver sulfadiazine, electron microscopy, and biochemical techniques have shown that the mechanism of action of silver sulfadiazine against bacteria differs from that of silver nitrate and sodium sulfadiazine. Silver sulfadiazine acts only on the cell membrane and cell wall, thereby producing a bactericidal effect. Its specific mechanism of action is not yet determined, but the effectiveness of silver sulfadiazine may stem from synergistic effects or the combined action of its components. Silver is a bactericide that can bind to a variety of targets. Silver ions can bind to nucleophilic amino acids, as well as thiol, amino, imidazole, phosphate, and carboxyl groups in proteins, leading to protein denaturation and inhibiting enzyme activity. Silver can bind to cell membranes and proteins, causing membrane proton leakage and ultimately cell death. Sulfadiazine is a competitive inhibitor of bacterial para-aminobenzoic acid (PABA), a substrate of dihydropteroic acid synthase. This inhibitory response is crucial for the synthesis of folic acid by these microorganisms.
A topical antibacterial agent used for burn treatment.
See also: sulfadiazine (active moiety); silver ions (active moiety); enrofloxacin; silver sulfadiazine (component).
Indications
For the prevention and treatment of wound infections in patients with second- and third-degree burns.
Mechanism of Action
Studies using radioactive microparticle-based silver sulfadiazine, electron microscopy, and biochemical techniques have shown that the mechanism of action of silver sulfadiazine against bacteria differs from that of silver nitrate and sodium sulfadiazine. Silver sulfadiazine acts only on the cell membrane and cell wall, thereby producing a bactericidal effect. Its specific mechanism of action is not yet clear, but the effectiveness of silver sulfadiazine may stem from synergistic effects or the combined action of its components. Silver is a biocidal agent that can bind to a variety of targets. Silver ions can bind to nucleophilic amino acids, as well as thiol, amino, imidazole, phosphate, and carboxyl groups in proteins, leading to protein denaturation and inhibition of enzyme activity. Silver ions can also bind to cell membranes and proteins, causing membrane proton leakage and ultimately leading to cell death. Sulfadiazine is a competitive inhibitor of bacterial para-aminobenzoic acid (PABA), a substrate of dihydropteroate synthase. This inhibition is crucial for folic acid synthesis in these organisms.

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Pharmacodynamics
Silver sulfadiazine has broad-spectrum antibacterial activity. It is bactericidal against a variety of Gram-negative and Gram-positive bacteria, and is also effective against yeast. Silver sulfadiazine is not a carbonic anhydrase inhibitor, therefore it may be suitable in situations where carbonic anhydrase inhibitors are contraindicated.

C10H9AGN4O2S

357.14

355.949

22199-08-2

441244

White to off-white solid powder

1.496g/cm3

512.6ºC at 760 mmHg

285 °C (dec.)(lit.)

263.8ºC

1.28E-10mmHg at 25°C

3.114

1

6

3

18

327

0

O=S([N-]C1=NC=CC=N1)(C2=CC=C(N)C=C2)=O.[Ag+]

UEJSSZHHYBHCEL-UHFFFAOYSA-N

InChI=1S/C10H9N4O2S.Ag/c11-8-2-4-9(5-3-8)17(15,16)14-10-12-6-1-7-13-10;/h1-7H,11H2;/q-1;+1

silver;(4-aminophenyl)sulfonyl-pyrimidin-2-ylazanide

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 (e.g. under nitrogen), 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)

H2O : < 0.1 mg/mL
DMSO : < 1 mg/mL

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.)