Sulfadimethoxine

Sulfadimethoxine is a long acting antibiotic [1].

Sulfadimethoxine is developed as a safe and effective antimicrobial agent for a wide range of infections including acute rhinitis, frontal abscess, pelvic inflammatory disease and upper respiratory infection et al. In the clinical study, sulfadimethoxine is reported to have no side reaction. Besides that, a single dose of 25 mg/kg of sulfadimethoxine is enough for treatment of moderate to severe infection. Most of the patients treated with sulfadimethoxine appear to respond rapidly to the therapy. Sulfadimethoxine is now most frequently used as veterinary medicine. For instance, sulfadimethoxine is found to have anticryptosporidial activity. It is highly effective in reducing the severity of cryptosporidial infection in immunosuppressed-rat model [1, 2].

References:
[1] MOSELY MJ Jr. Clinical results with sulfadimethoxine (madribon); a new long action antibacterial. J Natl Med Assoc. 1959 Jul;51(4):258-62.
[2] Rekg JE, Hancock ML, Woodmansee DB. Anticryptosporidial activity of sulfadimethoxine. Antimicrob Agents Chemother. 1988 Dec;32(12):1907-8.

LC-MS/MS methods for sulfadimethoxine and ormetoprim analysis in feed and fish fillet and a leaching study for feed after alternative procedures for the incorporation of drugs.[Pubmed:27915582]

Food Addit Contam Part A Chem Anal Control Expo Risk Assess. 2017 Apr;34(4):501-508.

This paper describes the method development for Sulfadimethoxine (SDM) and ormetoprim (OMP) quantitation in fish feed and fish fillet employing LC-MS/MS. In order to assess the reliability of the analytical method, valuation was undertaken as recommended by guidelines proposed by the Brazilian Ministry of Agriculture. The calibration curve for the quantification of both drugs in feed showed adequate linearity (r > 0.99), precision (CV < 12%) and trueness ranging from 97% to 100%. The method for the determination of SDM and OMP residues in fish fillet involved a simple sample preparation procedure that had adequate linearity (r > 0.99), precision (CV < 16%) and trueness around 100%, with CCalpha < 100.2 ng g(-)(1) and CCbeta < 100.4 ng g(-)(1). With a goal of avoiding the risk of drug leaching from feed into the aquatic environment during fish medication via the oral route, different procedures for drug incorporation into feed were evaluated. Coating feed pellets with ethyl cellulose polymer containing the drug showed promising results. In this case, medicated feed released drugs to water at a level below 6% when the medicated feed stayed in the water for up to 15 min.

Sulfate radical-based oxidation of antibiotics sulfamethazine, sulfapyridine, sulfadiazine, sulfadimethoxine, and sulfachloropyridazine: Formation of SO2 extrusion products and effects of natural organic matter.[Pubmed:28363182]

Sci Total Environ. 2017 Sep 1;593-594:704-712.

The widespread occurrence of sulfonamide antibiotics in the environment has raised great concerns about their potential to proliferate antibacterial resistance. Sulfate radical (SO4(*-)) based advanced oxidation processes (SR-AOPs) are promising in-situ chemical oxidation (ISCO) technologies for remediation of soil and groundwater contaminated by antibiotics. The present study reported that thermally activated persulfate oxidation of sulfonamides (SAs) bearing six-membered heterocyclic rings, e.g., sulfamethazine (SMZ), sulfapyridine (SPD), sulfadiazine (SDZ), Sulfadimethoxine (SDM), and sulfachloropyridazine (SCP), all produced SO2 extrusion products (SEPs), a phenomenon that is of potential importance, but not systematically studied. As an electrophilic oxidant, SO4(*-) tends to attack the aniline moiety, the reactive site of SAs, via electro-transfer mechanism. The resulting anilinyl radical cations are subjected to further intermolecular Smiles-type rearrangement to produce SEPs. Formation of SEPs is expected to occur in other SR-AOPs as well. The temperature-dependent evolution pattern of SEP of SMZ, 4-(2-imino-4,6-dimethylpyrimidin-1(2H)-yl)aniline, can be well fitted by kinetic modeling concerning sequential formation and transformation of intermediate product. The presence of natural organic matter (NOM) influenced the evolution patterns of 4-(2-imino-4,6-dimethylpyrimidin-1(2H)-yl)aniline significantly. Toxicological effects of SEPs on ecosystem and human health remain largely unknown, thus, further monitoring studies are highly desirable.

Sulfadimethoxine in giant freshwater prawns (Macrobrachium rosenbergii): an attempt to estimate the withdrawal time by a population pharmacokinetic approach.[Pubmed:27925222]

J Vet Pharmacol Ther. 2017 Oct;40(5):476-485.

The fates of Sulfadimethoxine (SDM) for different routes of administration were investigated in muscle tissue of giant freshwater prawns, Macrobrachium rosenbergii, following either intramuscular (i.m.) or gavage administration at a dosage of 50 mg/kg body weight (b.w.). The depletion patterns of SDM were also examined after medicated feed treatment at the feeding concentration of 10 g/kg of feed twice a day at a rate of 1% of total b.w. for five consecutive days. The concentration of SDM in prawn muscle tissue was measured using a high-performance liquid chromatography (HPLC) equipped with ultraviolet detector. Noncompartmental analyses were used to estimate basic pharmacokinetic parameters for the i.m. and gavage data, while a population model was developed to analyze the entire data set including the feed group. Using the Monte Carlo simulations, the withdrawal times (WT) for the orally administered SDM in feed supplement were determined. Maximum concentration of SDM was significantly higher in the i.m. than in the gavage group, and the area under the curve (AUC) value for relative bioavailability following gavage administration was 25.6%. Using Monte Carlo simulation, for a maximum residue limit (MRL) of 0.1 mug/g, the WT for muscle after oral administration of SDM in feed was estimated to be 67 h, while for a MRL of 0.2 mug/g, the WT was estimated to be of 54 h.

A colorimetric aptasensor for sulfadimethoxine detection based on peroxidase-like activity of graphene/nickel@palladium hybrids.[Pubmed:28283448]

Anal Biochem. 2017 May 15;525:92-99.

A sensitive, rapid and label-free colorimetric aptasensor for Sulfadimethoxine (SDM) detection was developed based on the tunable peroxidase-like activity of graphene/nickel@palladium nanoparticle (Gr/Ni@Pd) hybrids. The addition of the SDM aptamer could inhibit the peroxidase-like catalytic activity of the hybrids. However, the target SDM and aptamer could be triggered tightly and recover the catalytic activity of the Gr/Ni@Pd hybrids. Due to the peroxidase-like catalytic activity, Gr/Ni@Pd could catalyze the decomposition of H2O2 with releasing hydroxyl radicals which further oxidized reagent 3, 3', 5, 5'-Tetramethylbenzidine (TMB) to oxTMB accompanied with a colorless-to-blue color change. The original color change could be applied to obtain quantitative detection of SDM, due to the relationship between the concentration of the target and the color difference. As a result, this approach performed a linear response for SDM from 1 to 500 ng/mL with a limit detection of 0.7 ng/mL (S/N = 3) under the optimized conditions and realized the detection of SDM in spiked lake water samples. Therefore, this colorimetric aptasensor was an alternative assay for SDM detection in real water. Moreover, with its design principle, this work might be applied to detecting other small molecule by employing appropriate aptamer.