Quinolones (4-quinolones), also known as pyruvates or pyridone acids, are a class of synthetic antibacterial drugs. Quinolones are antibacterial drugs that mainly act on Gram-negative bacteria and have a weaker effect on Gram-positive bacteria (some varieties have better antibacterial effects on Staphylococcus aureus).
2. Quinolone structure
The 4-quinolone core has carboxylic acid groups at the 3 position, the introduction of a fluorine atom at the 6 position can enhance the antibacterial effect and the antibacterial activity of Staphylococcus aureus; the introduction of the piperazine ring at the 7 position can improve the antibacterial activity against Staphylococcus aureus and Pseudomonas aeruginosa Role (such as norfloxacin), the piperazine ring is replaced by the methylpiperazine ring (such as pefloxacin), then fat solubility increases, intestinal absorption increases, cell penetration increases, and half-life is extended.
The introduction of a second fluorine atom at the 8 position can further improve intestinal absorption and extend the half-life (such as lomefloxacin, etc.), N-1 modified with a cyclopropyl group (ciprofloxacin) or an oxazine group (oxyfluoride (Floxacin) can expand the antibacterial spectrum and enhance the antibacterial activity against chlamydia, mycoplasma and mycobacteria (tuberculosis and leprosy, etc.). The oxazine ring can also increase the water solubility, so that the drug is not metabolized in the body and excreted through the urine in the original form.
How do quinolones work?
The basic skeletons of quinolone antibiotics are all nitrogen (hetero) bicyclic ring structures. Quinolone and other antibacterial drugs have different action points. They target bacterial deoxyribonucleic acid (DNA). The double-stranded DNA of bacteria is twisted into loops or spirals (called supercoils).
The enzyme that causes DNA to form supercoils is called DNA gyrase, and quinolones hinder this enzyme, further causing irreversible damage to bacterial DNA and causing bacteria, the cells no longer divide. They show selective toxicity to bacteria. At present, the resistance of some bacteria to many antibiotics can be widely spread due to plasmid transmission.
Quinolone is divided into first, second, third, and fourth generations according to the order of invention and its antibacterial properties.
The first-generation quinolones only have antibacterial effects on Escherichia coli, Shigella, Klebsiella, and a few Proteus. Because of the poor efficacy, it has rarely been used.
The second-generation quinolones have expanded their antibacterial spectrum, and have certain antibacterial effects against Enterobacter, Citrobacter, Pseudomonas aeruginosa, and Serratia.
The antibacterial spectrum of the third-generation quinolones has been further expanded. It also has antibacterial effects on gram-positive bacteria such as staphylococcus, and further strengthens antibacterial effects on some gram-negative bacteria. This generation of drugs have fluorine atoms in the molecules. Therefore, called fluoroquinolone.
The fourth-generation quinolones are structurally modified compared to the previous three-generation drugs. The introduction of 8-methoxy group in the structure helps to strengthen the anti-anaerobic bacteria activity, while the azadioxane structure at the C-7 position strengthens the anti-gram positive Bacteria activity and maintain the original activity against Gram-negative bacteria, adverse reactions are smaller, but the price is more expensive. Increased antibacterial activity against Gram-positive bacteria, increased effects on anaerobic bacteria including Bacteroides fragilis, and enhanced effects on typical pathogens such as Mycoplasma pneumoniae, Chlamydia pneumoniae, Legionella and Mycobacterium tuberculosis.
Quinolone drugs have the following contents: nalidixic acid, pipemidic acid, norfloxacin, ciprofloxacin, enoxacin, ofloxacin, levofloxacin, fleroxacin, lomefloxacin, pefloxacin, toxa Ofloxacin, Sifloxacin, etc.
The side effects of Quinolones
1. Quinolone toxicity
Quinolone drugs are widely used in the treatment of human and animal diseases. Due to the residues of quinolone drugs in animal body tissues, quinolone antibiotics are accumulated in the human body after human consumption of animal tissues, resulting in serious tolerance of human diseases to the drug The medicinal properties affect the treatment of human diseases.
As the saying goes, it is a drug that is three-way poisoning. Long-term intake of animal-derived foods containing quinolones is harmful to the human body but not beneficial.
2. Quinolone contraindications
A. Gastrointestinal reactions: nausea, vomiting, discomfort, pain, etc.;
B. Central reactions: headache, dizziness, poor sleep, etc., and may cause mental symptoms;
C. Because this class of drugs can inhibit the effect of γ-aminobutyric acid (GABA), it can induce epilepsy, and those with a history of epilepsy should be used with caution;
D. This type of medicine can affect cartilage development, pregnant women and minor children should be used with caution;
E. Crystalline urine can be produced, especially in alkaline urine;
F. Large-dose or long-term application of this class of drugs is likely to cause liver damage.
3. Quinolone interactions
A. Alkaline drugs, anticholinergic drugs, and H2 receptor blockers can all reduce the acidity of gastric juice and reduce the absorption of this type of drugs.
B. Rifampicin (inhibitor of RNA synthesis) and chloramphenicol (inhibitor of protein synthesis) can reduce the effects of this class of drugs, completely eliminate the effects of nalidixic acid and haloperic acid, and make fluazamic acid The effect of ciprofloxacin is partially offset.
C. Fluoroquinolones can inhibit the metabolism of theophylline. When combined with theophylline, the plasma concentration of theophylline will increase, and the toxic reaction of theophylline may occur, so attention should be paid.
4. Qllergic to quinolones
Rashes, itching of the skin, and occasionally exudative erythema multiforme and angioedema. A small number of patients with photosensitive disease have photosensitive reactions.
Characteristics of Quinolones 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 Quinolones Test
Quinolones Test Kit is a colloidal gold immune-chromatography assay that specially designed for detecting sulfonamides residue in egg and egg products and meets EU MRL. This kit can be applied for on-site rapid testing by various departments.
Samples of Quinolones Test
Samples include: egg and egg products
Detection limit of Quinolones Test
The LOD may change according to requirement or specimen's difference, please refer to kit instruction for further details.
The importance of Quinolones Test
Quinolones Test can help manufacturers, regulatory agencies, and the public monitor product quality and help humans protect their health.
Components for Quinolones Test
1. Micro-Well Reagent: 8 tests/tube, 12 tubes/box
2. Test Strip: 8pcs/tube, 96pcs/box
3. Manual Instruction: 1pc
Materials for Quinolones Test
1. Sample Tube
2. Pipette & Pipette Tip
How to use Quinolones Test?
1. Add 200ul test solution into a well, then pipet up and down for 10 times to completely mix the sample with the reagent in the well.
2. Then incubate for 3min.
3. Insert the test strip into the micro-well-plate with the sample pad fully dipped.
4. After 5 minutes, read the results.
When antibiotics were first used on humans, we regarded them as "nostrum". As the problem of antibiotic abuse continues to worsen, their resistance has also brought huge harm to humans.
Therefore, in daily life, we should avoid food with antibiotic residues. The first step to self-help: we need to detect antibiotic residues.
How to order Quinolones Test?
Please check the online catalog and contact our sale representative via email: email@example.com or fill out contact form below: