With reference to carbon nanotubes
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?
- 1 and 2 only
- 2, 3 and 4 only
- 1, 3 and 4 only
- 1, 2, 3 and 4
Answer: D
Explanation
Carbon nanotubes (CNTs) are allotropes of carbon, made of graphite and constructed in cylindrical tubes with nanometer in diameter and several millimeters in length. Their impressive structural, mechanical, and electronic properties are due to their small size and mass, their strong mechanical potency, and their high electrical and thermal conductivity.
CNTs have been successfully applied in pharmacy and medicine due to their high surface area that is capable of adsorbing or conjugating with a wide variety of therapeutic and diagnostic agents (drugs, genes, vaccines, antibodies, biosensors, etc.). They have been first proven to be an excellent vehicle for drug delivery directly into cells without metabolism by the body. Then other applications of CNTs have been extensively performed not only for drug and gene therapies but also for tissue regeneration, biosensor diagnosis, enantiomer separation of chiral drugs, extraction and analysis of drugs and pollutants. Hence, statements 1 and 3 are true.
CNTs are used in various biomedical applications like biosensors, diagnostic agents to visualize cancer cells. A multiwalled carbon nanotube–polyurethane nanocomposite
(MWCNT-PU) can be used as vascular graft or blood capillaries. The disruption of red blood cells by PU and MWCNT-PU has been studied by measuring the absorbance of free hemoglobin.
It has been found that the MWCNTs with an oxygen-containing functional group are well dispersed in polyurethane matrix. The number of platelets adhered to the MWCNTPU nanocomposite surface was remarkably reduced in comparison to that of the PU surface. Investigation of platelet activation was done by the analysis of conformational changes in glycoprotein measured via flow cytometry.
It is expected that this enabling technology would facilitate the making of nanodevices using these blood-compatible nanomaterials as building blocks for biomedical application such as artificial implants, including structural tissue replacements, that is, artificial blood vessels, or functional devices such as drug delivery matrixes. Hence, statement 2 is true.
Multiple types of microbes including bacteria and fungi have the ability to degrade carbon nanotubes (CNTs), graphene (GRA), and their derivatives and in the future more species with this ability will be found. Hence, CNTs are biodegradable. Therefore, statement 4 is true.
- Exam Year: 2020