Sulfa drugs are synthetic antibacterial drugs that have been used clinically for nearly 50 years, including: sulfamethazine (SM2), sulfisoxazole (SIZ), sulfadiazine (SD), sulfamethoxazole (SMZ), Sulfamethoxine (SMD), sulfadimethoxine (SDM), sulfacetamide (SA), sulfadiazine silver salt (SD-Ag), methanesulfonate (SML).
It has the advantages of broad antibacterial spectrum, stable properties, easy use, and no food consumption during production. Especially after the discovery of the antibacterial synergist-trimethoprim (TMP) in 1969, the combined application with sulfonamides can enhance its antibacterial effect and expand the scope of treatment. Therefore, although numerous antibiotics have come out, sulfa drugs are still important chemotherapy drugs.
2. Antibacterial effect
Sulfonamides have inhibitory effects on many Gram-positive bacteria and some Gram-negative bacteria, Nocardia, Chlamydia and certain protozoa (such as Plasmodium and Amoeba). Among the positive bacteria, streptococcus and pneumococcus are highly sensitive; Staphylococcus and Perfringens are moderately sensitive.
Among the negative bacteria, the sensitive ones are meningococcus, Escherichia coli, Proteus, Shigella, Pneumoniae and Yersinia. It has no effect on viruses, spirochetes and trypanosoma. It is not only ineffective for Rickettsia, but can promote its reproduction. It is generally believed that the difference in antibacterial power of different sulfa drugs is in quantity, not in quality. The compound with the high potency for one type of bacteria has high potency for other types of bacteria.
3. Mechanism of action
Bacteria cannot directly use the folic acid in their growth environment, but use the p-aminobenzoic acid (PABA), dihydropteridine and glutamic acid in the environment to synthesize dihydrofolate under the catalysis of dihydrofolate synthase in the bacteria.
Dihydrofolate forms tetrahydrofolate under the action of dihydrofolate reductase. Tetrahydrofolate, as a coenzyme of one-carbon unit transferase, participates in the synthesis of nucleic acid precursors (purine, pyrimidine). Nucleic acid is an essential component for bacterial growth and reproduction.
The chemical structure of sulfa drugs is similar to that of PABA, and it can compete with PABA for dihydrofolate synthase, which affects the synthesis of dihydrofolate, thereby inhibiting bacterial growth and reproduction. Since sulfa drugs can only inhibit bacteria but have no bactericidal effect, the elimination of pathogenic bacteria in the body ultimately depends on the body's defense capabilities.
The hazards of sulfonamides
After the 1940s, the continuous discovery and development of various antibacterial drugs gradually replaced sulfonamides clinically. But sulfa drugs still have their unique advantages, such as broad antibacterial spectrum, stable properties, convenient use, low price, and no food consumption.
Therefore, sulfa drugs are still important chemical drugs in the anti-infective treatment of livestock. The hazards of sulfa drug residues mainly include toxic effects, allergic effects, ecological pollution, causing double infections and the formation of drug-resistant strains.
After long-term intake of animal foods containing sulfa drugs, the drugs continue to accumulate in the human body. When they accumulate to a certain level, they will have toxic effects on the human body and cause kidney damage, especially acesulfame in the urine. Its solubility is low, and the damage to the kidney is great after the precipitation of crystals.
After being administered to animals, about 60% to 90% of sulfa drugs will be excreted through animal feces, and they can still exist stably after entering the environment, destroying the balance of microorganisms in soil and water and causing environmental pollution. In addition, sulfa drugs have a great impact on soil respiration, organic matter content, the number of microorganisms and invertebrates, the oxygen content of water, the number of algae and phytoplankton in the water.
Sulfonamides are mainly left in meat, eggs, and milk in the form of original drugs or degradation products. People ingest them through meat, eggs, milk and other animal foods. In mild cases, rash, nausea, vomiting, dizziness and other toxicities can occur. Sulfonamide residues can also damage the human hematopoietic system, causing hemolytic anemia, agranulocytosis, thrombocytopenia and eosinophilia. For example, in the treatment of cow mastitis, if the milk abandonment period is not implemented, after people ingest these milk or dairy products containing drug residues, among patients with allergic reactions, the mild ones have skin itching and urticaria, and the severe ones have vascularity Edema.
In order to ensure the safety and effectiveness of animal drugs, and the safety of humans after ingesting animal food, when using sulfa drugs in clinical use, it is not allowed to arbitrarily increase the dose, the number of medications or extend the course of treatment to prevent accumulation of poisoning and increased residue affecting human health.
Characteristics of Sulfonamides Test
1.7min reading results
2. Detection limits respond to EU and US FDA norms
3. Neither professionals nor equipment required
4. Easy to operate and read
Detection methods for Sulfonamides Test
The Sulfonamides Test Kit is a colloidal gold immune-chromatography assay that specially designed for detecting sulfonamides residue in raw milk, milk powder, pasteurized milk and meets EU MRL. This kit can be applied for on-site rapid testing by various departments.
Samples of Sulfonamides Test
Samples include: raw milk, milk powder, pasteurized milk.
Detection limit of Sulfonamides Test
The LOD may change according to requirement or specimen's difference, please refer to kit instruction for further details.
The importance of Sulfonamides Test
Sulfonamides Test can help manufacturers, regulatory agencies, and the general public monitor product quality and help humans protect their health.