Q. With reference to carbon nanotubes, consider the following statements :
- They can be used as carriers of drugs and antigens in the human body.
- They can be made into artificial blood capillaries for an injured part of human body.
- They can be used in biochemical sensors.
- Carbon nanotubes are biodegradable.
Which of the statements given above are correct? (UPSC Prelims 2020)
Answer:
1, 3 and 4 only
Notes: The correct answer is
[C] 1, 3 and 4 only.
- Statement 1 (Correct): CNTs are widely researched as carriers for drugs and antigens. Their high surface area and ability to penetrate cell membranes allow for targeted delivery, improving the efficacy of treatments like chemotherapy.
- Statement 2 (Incorrect): While CNTs are used as "scaffolds" in tissue engineering, making them into artificial blood capillaries is not currently a standard or viable medical application. A major hurdle is that CNTs can trigger blood platelet activation, leading to blood clotting (thrombosis), making them unsafe for direct use as blood vessels.
- Statement 3 (Correct): Their unique electrical properties make them ideal for biochemical sensors. Even a tiny change in the environment (like a single molecule of a biomarker) significantly alters their conductivity, allowing for ultra-sensitive detection.
- Statement 4 (Correct): Contrary to early beliefs that they were indestructible, research has shown that certain functionalized CNTs are biodegradable. They can be broken down by oxidative enzymes like myeloperoxidase (found in human white blood cells).
Statement 2 is incorrect also because there is a difference between "theoretical possibilities" and "proven/safe applications" in cutting-edge technology questions.