Determining the Ibuprofen Concentration in Liquid-Filled Gelatin Capsules To Practice Collecting and Interpreting Experimental Data, and Evaluating the Methods and Accuracy of Quality Testing

Abstract

A laboratory experiment to determine the concentration of the anti-inflammatory drug ibuprofen in liquid gelatin capsule dosage forms, suitable for undergraduate chemistry or pharmacy students, is described. Either individually, or in small teams, the students digest two 200 mg capsules in a KOH solution. While the capsules are digesting the students prepare a range of ibuprofen standards and determine their UV absorbance at 264 nm. Next, the students use the data to both determine the drug's extinction coefficient using the Beer−Lambert equation and to plot a calibration graph. Using both the extinction coefficient and the calibration graph the students are then required to determine the amount of ibuprofen in each of their capsules. In undertaking the laboratory class, the students are required to complete a results data sheet, determine whether the capsules are within specification, and answer questions that prompt them to evaluate the different calculation methods and the accuracy of the tests. In their final exam, the students were asked three multiple choice questions and one multistep calculation question related to the laboratory class. The results of the students' final exam show that the learning objectives of the laboratory were broadly met, with students being able to demonstrate an understanding behind the science of the laboratory, and an ability to undertake simple, as well as complex, calculations.

Enhanced Sensitivity Using MALDI Imaging Coupled with Laser Postionization (MALDI-2) for Pharmaceutical Research

“…In this case the formation of the [M] +• ion of ibuprofen can be explained by a 2-photon resonance enhanced multiphoton photoionization (REMPI) process. Ibuprofen exhibits a peak UV-absorption at 263 nm, hence radical cation formation can be attributed to absorption of the MALDI-2 laser light (λ = 260 nm) 42 by ibuprofen and subsequent absorption of a second photon ionizes the molecules. Radical cations were also detected in the MALDI-2 analysis of aromatic ketoconazole, doxorubicin, and caffeine (Figure 2B, circle labels).…”

What’s in That Medicine: An Inquiry-Based Activity to Introduce Medicinally Active Natural Products and Metals

“…11 Pepto-Bismol has been the topic of other laboratory activities because of its unique and significant metal content. 12 There are some published traditional laboratory activities that address pharmaceuticals, although many are not suitable for high school students due to their need for specialized equipment, 3,13,14 and few address metals in medicine. 15 The inquiry-based activity described herein evolved from an adapted traditional lab activity where students were given stepby-step instructions to isolate and quantify the amount of bismuth metal in Pepto-Bismol 16 (see Supporting Information).…”

“…Pepto-Bismol has been the topic of other laboratory activities because of its unique and significant metal content . There are some published traditional laboratory activities that address pharmaceuticals, although many are not suitable for high school students due to their need for specialized equipment, ,, and few address metals in medicine …”