KR-20260065659-A - Aptamer specifically binding to Ciprofloxacin and use thereof

Abstract

The present invention relates to an aptamer that specifically binds to ciprofloxacin and its uses. As a result of efforts to develop an aptamer with high binding affinity to ciprofloxacin, an aptamer with excellent specificity and binding affinity even to small target molecules was discovered in silico, which significantly reduces time and cost compared to conventional SELEX. Furthermore, it was confirmed that the discovered aptamer exhibits excellent high sensitivity and specificity for ciprofloxacin. Thus, the aptamer of the present invention can selectively detect only the target ciprofloxacin in a sample containing a minute amount of ciprofloxacin.

Inventors

• 윤순일
• 찬드란 크리스나라지
• 아스마리 미스가나 맹기스투

Assignees

• 전북대학교산학협력단

Dates

Publication Date

20260511

Application Date

20241101

Claims (6)

1. An aptamer that specifically binds to ciprofloxacin, comprising the nucleotide sequence of SEQ ID NO. 1.
2. A composition for detecting ciprofloxacin comprising the aptamer of claim 1.
3. A kit for detecting ciprofloxacin comprising the aptamer of claim 1.
4. A sensor for detecting ciprofloxacin comprising the aptamer of claim 1 and a substrate on which the aptamer is immobilized.
5. A method for detecting ciprofloxacin comprising the step of treating a sample with the aptamer of claim 1.
6. A method for detecting ciprofloxacin according to claim 5, wherein the sample is taken from water, soil, waste, food, the inside of an animal’s intestine, or the tissue of an animal or plant.

Description

Aptamer specifically binding to Ciprofloxacin and use thereof The present invention relates to an aptamer that specifically binds to ciprofloxacin and its uses. Aptamers are small oligonucleotides that bind specifically and selectively to target molecules. As is widely known, nucleic acids are linear polymers in which nucleotides are linked by covalent bonds; generally, nucleic acids such as DNA and RNA serve as storage vessels for information to express proteins with cellular structural and enzymatic activities. Meanwhile, nucleic acids form three-dimensional structures and become stabilized by forming complexes through interactions with specific substances; due to this characteristic, nucleic acids can act as ligands for specific substances, including proteins. Accordingly, aptamers that bind to specific substances with high binding affinity and specificity can be produced from a library of single-stranded nucleic acids arranged in various base sequences through a specific selection process and base sequence determination. Furthermore, unlike antibodies, which are conventional sensing materials used in the sensor field, aptamers are nucleic acid structures, so they exhibit excellent thermal stability. Since they are synthesized in vitro, they do not require animals or cells, making them economical in terms of production costs. Additionally, because there are no restrictions on target substances, aptamers can be synthesized for a wide range of targets, from biomolecules such as proteins and amino acids to low-molecular-weight organic chemicals like endocrine disruptors, antibiotics, and pharmaceutical residues, as well as bacteria and viruses. Meanwhile, the first quinolone class of drugs was 1,8-naftiridine, which was isolated from a distillate during the synthesis of the antimalarial drug chlorquine in 1962. Since its initial discovery, more than 25 derivatives have been synthesized, with quinoline-based compounds created to improve the antibacterial spectrum and antibacterial activity. Early quinolone antibiotics developed included flumequine and oxylic acid. These agents are hetero-aromatic, bicycline compounds that exhibited excellent activity against many aerobic bacteria but showed somewhat weak activity against anaerobic bacteria. Subsequently, to improve the efficacy of these agents, fluoroquinolone antibiotics, a second generation of quinolones with a wider antibacterial range, were developed by adding fluorine (F) to the 6th carbon position of quinoline. Regarding the mechanism of action of quinolones, it is known that they possess antimicrobial activity by inhibiting bacterial DNA gyrase activity, thereby interfering with various cellular functions, including DNA replication and nuclear transcription. Continuous consumption of zoonotic quinolones through food can lead not only to the formation of drug-resistant bacteria but also to side effects such as interstitial pneumonia and Achilles tendinitis; furthermore, since cartilage dysplasia can occur particularly in children under the age of 18, regulations on their use are necessary. The most significant side effect of fluoroquinolone antibiotics is the rapid emergence of antibiotic-resistant strains among numerous pathogens. In Korea, enrofloxacin, ciprofloxacin, norfloxacin, and ofloxacin are administered via feed additives, drinking water, and injection for the prevention and treatment of E. coli , Mycoplasma, Pasteurella, and Salmonella, which are prevalent in the poultry industry. However, the National Veterinary Science Quarantine Service announced that it would completely ban the domestic manufacturing and import of four zoonotic fluoroquinolone antibiotics—ciprofloxacin, norfloxacin, pefloxacin, and ofloxacin—which are used in both humans and animals, starting July 1, 2008. This decision was made in consideration of the fact that while fluoroquinolone antibiotics are used as effective treatments for human infections, treatment options for these infections become very limited if resistance develops, and that these products are not approved as veterinary drugs in developed countries. Conventional methods for detecting antibiotic residues involved preparing different test solutions based on the dissolved components to extract and purify the residues, followed by quantification using liquid chromatography. However, existing methods offered only a limited number of test methods based on the dissolved substances, and preparing separate solutions was cumbersome. Furthermore, accurate quantification was difficult due to the potential loss of the detected substance during the extraction and purification processes. While specific aptamers for binding to low-molecular-weight harmful substances—such as residual pharmaceuticals, antibiotics, and endocrine disruptors—can be applied as medical technologies for detecting and diagnosing harmful substances in living organisms, including the human body, as well as in samples remaining in water sources and r