Glucose in blood can be quantitatively determined with

Options

A. Tollen reagent
B. Benedict solution
C. Alkaline iodine solution
D. Bromine water

Explanation

To determine the quantitative presence of glucose in blood, we can follow these steps:

### Step 1: Understand the nature of glucose
Glucose is a simple sugar (monosaccharide) that contains an aldehyde group (-CHO). This functional group is crucial for its reactivity in certain chemical tests.

### Step 2: Identify the reagents
We are given several reagents: Tollens' reagent, Benedict's solution, alkaline iodine solution, and bromine water. We need to identify which of these can quantitatively determine glucose.

### Step 3: Analyze each reagent
1. **Tollens' Reagent**: This reagent is specifically used to test for aldehydes. Since glucose contains an aldehyde group, it can react with Tollens' reagent, leading to a positive result. However, it is primarily qualitative.

2. **Benedict's Solution**: This solution is used to test for reducing sugars, which includes glucose. When glucose is present, it reduces the copper(II) ions in the Benedict's solution to copper(I) oxide, resulting in a color change. This method can be used quantitatively to determine the concentration of glucose in a sample.

3. **Alkaline Iodine Solution**: This reagent is typically used to test for starch, not glucose. Therefore, it is not suitable for determining glucose levels.

4. **Bromine Water**: This reagent is used to test for unsaturation (double bonds) in compounds and is not specific for glucose.

### Step 4: Conclusion
The most appropriate reagent for the quantitative determination of glucose in blood is **Benedict's solution**.

### Final Answer
Glucose in blood can be quantitatively determined with **Benedict's solution**.

---