Question

Match List-I with List-II 

Choose the correct answer from the options given below: 
 

• 1. (A) - (I), (B) - (II), (C) - (III), (D) - (IV)
• 2. (A) - (I), (B) - (III), (C) - (II), (D) - (IV)
• 3. (A) - (I), (B) - (II), (C) - (IV), (D) - (III)
• 4. (A) - (III), (B) - (IV), (C) - (I), (D) - (II)

Hint:

Associate each spectroscopic technique with a key parameter: UV-Vis \(\rightarrow\) Concentration (Beer's Law); Fluorescence \(\rightarrow\) Environment/Conformation; IR \(\rightarrow\) Bond Vibrations/Functional Groups; ESR/EPR \(\rightarrow\) Unpaired Electrons/Dynamics.

Answer 1

The Correct Option is B

Step 1: Overview:
This question assesses your ability to link spectroscopic techniques with their common biophysical applications. Each technique explores different molecular properties.
Step 2: Technique Explanations:
(A) UV-Visible Spectroscopy: This technique measures light absorbance. Based on the Beer-Lambert Law (\(A = \epsilon cl\)), absorbance reflects concentration. It's often used to find the concentration of a sample, particularly proteins (280 nm) and nucleic acids (260 nm). Thus, (A) links with (I).
(B) Fluorescence Spectroscopy: This method is sensitive to a fluorophore's environment. Changes in protein folding, ligand binding, or other interactions alter fluorescence, making it useful for studying molecular conformation and dynamics. So, (B) matches (III).
(C) Infrared (IR) Spectroscopy: IR detects molecular bond vibrations. Vibration frequencies reveal bond types and environment. In biophysics, it determines protein secondary structure (e.g., amide I and II bands) and identifies functional groups, indicating chemical characteristics. Hence, (C) links with (II).
(D) Electron Spin Resonance (ESR): Also called Electron Paramagnetic Resonance (EPR), this technique targets molecules with unpaired electrons. By adding "spin labels," ESR provides information on mobility and environment. It's used to study fluidity of membranes and protein dynamics. Therefore, (D) matches (IV).
Step 3: Solution:
The correct matching is: (A)-(I), (B)-(III), (C)-(II), (D)-(IV). This corresponds to option 2.