In which of the following are hydrogels used ? 1. Controlled drug delivery in patients 2. Mobile air-conditioning systems 3. Preparation of industrial lubricants Select the correct answer using the code given below :
- (a) 1 only ✓ UPSC's answer
- (b) 1 and 2 only
- (c) 2 and 3 only
- (d) 1, 2 and 3
Why the answer is (a)
• Hydrogels are three-dimensional networks of hydrophilic polymers that hold large amounts of water while keeping their shape, and are soft and biocompatible.
• Their main use is biomedical: as carriers for controlled drug delivery, releasing medicines slowly in response to pH, temperature or enzymes, as well as in contact lenses, wound dressings and tissue engineering — item 1 is correct.
• Item 2 is wrong: mobile air-conditioning uses refrigerants and compressors; hydrogels play no role in it.
• Item 3 is wrong: industrial lubricants are oils, greases and solid lubricants like graphite, not water-swollen gels.
• Hence 1 only, option (a).
Why the other options are wrong
- (b) 1 and 2 only
- Hydrogels are not used in mobile air-conditioning.
- (c) 2 and 3 only
- Neither air-conditioning nor industrial lubricants use hydrogels.
- (d) 1, 2 and 3
- Only drug delivery is a genuine hydrogel application here.
Asked in the GS Paper I of the UPSC Civil Services Preliminary Examination 2024, held on 16 June 2024. Question and answer key: Union Public Service Commission. Explanation: UPSC Answer Check.