📘 Q.5 IAS Prelims 2024 — Science & Technology (Hydrogels)
🧷 Authentic Classroom Explanation by IAS Monk
📌 The Question:
In which of the following are hydrogels used?
- Controlled drug delivery in patients
- Mobile air-conditioning systems
- Preparation of industrial lubricants
Select the correct answer using the code given below:
(a) 1 only
(b) 1 and 2 only
(c) 2 and 3 only
(d) 1, 2 and 3
✅ Answer: (d) 1, 2 and 3
🧑🏫 Classroom Explanation:
Hydrogels are three-dimensional, cross-linked polymer networks that can absorb and retain large amounts of water without dissolving. Their unique water-holding, swelling, and viscoelastic properties make them useful across medicine, engineering, and industry.
🔹 Statement-wise analysis:
🔸 1. Controlled drug delivery ✅
Hydrogels are extensively used in biomedical applications because:
- They are biocompatible
- They allow controlled and sustained release of drugs
- Their porosity can be tuned for targeted delivery
Used in wound dressings, contact lenses, cancer therapy, and insulin delivery systems.
🔸 2. Mobile air-conditioning systems ✅
Hydrogels can absorb heat through evaporative cooling and moisture regulation.
They are explored in:
- Cooling electronic components
- Portable and mobile cooling systems
- Thermal regulation materials
🔸 3. Industrial lubricants ✅
Recent research shows hydrogels can act as:
- Low-friction, anti-wear lubricants
- Environment-friendly alternatives to oil-based lubricants
Their water-rich structure reduces surface wear effectively.
✔️ Hence, all three statements are correct.
🔍 Curiosity Raiser:
💧 How can a water-filled material behave like a solid — and still act as a lubricant?
That paradox is the core magic of hydrogels.
📚 Enrichment Notes (UPSC Edge):
- Hydrogels are also used in:
- Tissue engineering
- Artificial cartilage
- Soft robotics
- Smart sensors
- “Smart hydrogels” respond to pH, temperature, light, or electric fields
- Recently in news for glucose sensing via smartphones
🧘 IAS Monk Whisper:
🌱 The future belongs to materials that behave like life itself — adaptive, responsive, gentle.