Correct option is B
Super-resolution microscopy techniques overcome the diffraction limit of traditional fluorescence microscopy, improving spatial resolution. Let’s analyze each technique and match them to the correct principle.
Matching the Techniques to Their Principles:
Structured Illumination Microscopy (SIM) → (ii)
- Principle:Moire fringes The specimen is illuminated with a pattern of light and dark stripes to generate .
- How it Works:
- SIM uses a structured pattern of illumination (interference pattern) to extract fine spatial details.
- The Moire effect allows reconstruction of high-resolution images from multiple lower-resolution images.
- Key Feature:up to twice Enhances resolution the diffraction limit.
Stimulated Emission Depletion (STED) Microscopy → (i)
- Principle:donut-shaped depletion beam Focused excitation laser point is surrounded by a .
- How it Works:
- STED microscopy uses a two-laser system: an excitation laser and a depletion laser (which deactivates fluorescence in the peripheral region).
- The depletion beam creates a sharp fluorescence spot, reducing effective point spread and improving resolution.
- Key Feature:nanoscale resolution (~20 nm) Can achieve .
Photoactivated Localization Microscopy (PALM) → (iii)
- Principle:GFP (green fluorescent protein) Utilizes a variant of that is activated by a wavelength different from its excitation wavelength.
- How it Works:
- PALM stochastically activates and precisely localizes individual fluorophores, combining their positions to construct a high-resolution image.
- Key Feature:single-molecule resolution (~10-20 nm) Achieves .
Thus, the correct matching is:
- A-(ii) (SIM → Moire fringes)
- B-(i) (STED → Donut-shaped depletion beam)
- C-(iii) (PALM → GFP activation at different wavelengths)
