LABORATORY EXERCISE 3: Introduction to Standard Curves

Introduction to Standard Curves

• Learning Objectives:

  • Understand the fundamental operation of a spectrophotometer.

  • Develop the skill to generate and effectively utilize a standard curve.

  • Learn to evaluate and interpret variation observed in experimental data, particularly through statistical methods.

• Spectrophotometer Overview:

  • A common and essential laboratory instrument for biologists and other scientists.

  • Primarily used to measure the concentration of a molecule in a solution.

  • Typically, the molecule reacts with a reagent to produce a color change in the solution, allowing measurement in the visible spectrum.

  • Exceptions: Molecules like RNA or DNA absorb light in the non-visible UV light spectrum when in water.

• Exercise Outline:

  • Prepare dilutions of a standard solution (known concentration).

  • Measure the absorbance of these known concentrations.

  • Plot these data as an X-Y graph to create a standard curve.

  • Utilize this standard curve to determine the concentrations of **

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