Spektrofotometri UV-Vis Simple Simultaneous Equation (SSE): Kadar Parasetamol & Kofein dalam Tablet

Summary

This video demonstrates a method for determining the content of paracetamol and caffeine in tablets using UV-Visible spectrophotometry and simultaneous equations. The process includes preparing standard solutions, measuring absorption at specific wavelengths, and constructing calibration curves for both compounds. The procedure then guides the analysis of tablet samples, including dilution and spectrophotometric measurements. By using regression equations, the concentrations of both paracetamol and caffeine are calculated and compared to pharmacopoeia standards. This method offers an alternative approach for determining the active ingredients in pharmaceutical tablets, though optimization and validation may be necessary.

Takeaways

• 😀 The method for determining the content of paracetamol and caffeine in tablets uses UV-visible spectrophotometry techniques.
• 😀 High-Performance Liquid Chromatography (HPLC) is a common method for analyzing multicomponent formulations, but UV-visible spectrophotometry can also be an effective alternative.
• 😀 The simultaneous equations technique (SSE) is used for determining the concentration of two compounds that have overlapping UV spectra.
• 😀 The first step is to determine the maximum absorption wavelength (λmax) for paracetamol and caffeine using standard solutions.
• 😀 Paracetamol's maximum absorption wavelength is 243.25 nm, while caffeine's is 272.95 nm.
• 😀 Calibration curves are created by measuring the absorbance of standard solutions of paracetamol and caffeine at their respective λmax values.
• 😀 Regression equations are derived from the calibration curves, allowing the determination of the concentrations of both compounds in the tablet sample.
• 😀 The sample preparation involves weighing 20 tablets, grinding them into a fine powder, and extracting the active ingredients using water as a solvent.
• 😀 After dilution, the sample is filtered, and absorbance is measured at the determined λmax for both paracetamol and caffeine.
• 😀 The final concentration of paracetamol and caffeine is calculated using the regression equations from the calibration curves, and the results are compared to Indonesian pharmacopoeia standards.

Q & A

What is the primary objective of the experiment outlined in the script?

The primary objective of the experiment is to determine the concentrations of paracetamol and caffeine in tablets simultaneously using UV-Visible spectrophotometry, specifically through the Simple Simultaneous Equations (SSE) method.

Why is UV-Visible spectrophotometry used in this experiment?

UV-Visible spectrophotometry is used because it allows for the measurement of absorbance at specific wavelengths, enabling the determination of the concentration of different active compounds (paracetamol and caffeine) in a tablet without the need for separation.

What are the key tools and materials required for this experiment?

The key tools and materials required include a UV-Visible spectrophotometer, ultrasonic bath, digital scale, standard solutions of paracetamol and caffeine, aquades, 20 tablets as samples, and several glassware items.

How is the maximum wavelength for paracetamol determined?

The maximum wavelength for paracetamol is determined by preparing a standard solution and measuring its absorbance over a wavelength range of 200-400 nm using a spectrophotometer. The wavelength corresponding to the maximum absorbance is identified and noted.

What is the significance of determining the maximum wavelength for caffeine?

Determining the maximum wavelength for caffeine is crucial because it ensures the correct measurement of caffeine's absorbance, which is necessary for the accurate determination of its concentration in the tablet sample.

What is the purpose of creating calibration curves for paracetamol and caffeine?

The calibration curves for both paracetamol and caffeine are created to establish a relationship between absorbance and concentration. These curves allow for the determination of the concentration of these compounds in the tablet sample based on their absorbance values.

How is the sample of the tablet prepared for analysis?

The tablet sample is first weighed, then ground into a fine powder. A portion of the powder is dissolved in aquades, sonicated to ensure complete dissolution, and then diluted to a known volume in a volumetric flask.

What are the two dilution steps performed on the sample, and why are they necessary?

The sample undergoes two dilution steps. The first dilution involves a 5 mL sample to 50 mL solution, and the second involves a further 5 mL of the first dilution to 50 mL. These steps are necessary to achieve an appropriate concentration for accurate spectrophotometric analysis.

What are the key equations used to determine the concentration of paracetamol and caffeine in the sample?

The concentrations of paracetamol and caffeine are determined using two linear regression equations derived from the calibration curves. These equations relate the absorbance values at their respective maximum wavelengths (λ1 for paracetamol and λ2 for caffeine) to their concentrations.

What is the significance of performing the experiment at least three times?

Performing the experiment at least three times is important to ensure the accuracy and reproducibility of the results, providing reliable data for the final analysis and conclusions.