Reference no: EM133045147 , Length: word count:4000

BS7200 Experimental Techniques and Laboratory Practice - University of East London

1. Technique introduction - Introduce the technique used to produce the figure highlighting the key points, the specific subtype of technique used, the purpose of the technique, the main steps of the technique, the pros and cons of the techniques.

2. Figure interpretation: Provide and full and critical interpretation of the figure provided, including but not limited to:
the samples and genes/proteins analyzed,
eventual treatments or time-points,
the interpretation of any graphical representation (dots, bands, peaks, graphs, et cetera) including everything that leads to a complete understanding of the image.
The controls used (if they are missing, explain which controls you would expect and why)
The scientific message that can be understood from the figure.

Part 1-A
You have been provided with 1HNMR spectra (Next slide) to answer the following question.

Assign the 1HNMR spectra (solvent: d6-DMSO) of the following compound. Explain the multiplicity of the signals in NMR spectra and justify all the assignments

Part 1-B Effect of pH on drug absorption

This experiment illustrates the effect of pH on drug absorption in the human gastrointestinal (GI) tract. A model using aqueous solutions of different pH in contact with ethyl acetate is used to represent the Gl tract. The stomach has an acidic pH (approx 1-3) and the large intestine has a basic pH (approx 8); the aqueous solutions represent the aqueous contents of different sections of the gastrointestinal tract and the ethyl acetate, which is immiscible with water, represents the lipid component of the tissue lining. The aqueous mixtures of the following drugs (Indomethacin, Ephedrine and Morphine) at different pH (1.0 and pH 8.0) were extracted with ethyl acetate . The ethyl acetate extracts are spotted onto a TLC plate and viewed under the UV light. Following observations were recorded (Table 1). Answer the questions in the next slide.

Pharmaceutical Science

1. Explain the result in Table 1 with Indomethacin, ephedrine and Morphine in terms of pKa and site of absorption?

2. Explain in your own words what will happen to the chemical structure of Indomethacin when it is in solution at pH 1.0. Compare this to what will happen to the chemical structure of Indomethacin at pH 8.0. Highlight your answers by drawing appropriate chemical structures for Indomethacin at each of the pH values

3. Explain the result with ephedrine at pH 8.0. If appropriate Include a chemical equation which shows the conjugate acid and/or base formed by ephedrine at pH 8.0. Draw and label the predominant structures of ephedrine at pH 1, pH 7 and pH 10

Imagine you are working as an analyst in a pharmaceutical company where you have been assigned to check the identity and purity of aspirin that was received from an overseas company. You prepared standard aspirin, standard salicylic acid and the sample you received. Both standards (R1 and R2) and sample (S) were run using UPLC which gave the chromatographs shown below in the next page. Answer the following questions based on the chromatographs in the next page:

Identify aspirin and salicylic acid in Fig 3. Calculate the level of impurities.

Based on retention time which one (aspirin and salicylic acid) was eluted first and why?

Attachment:- Pharmaceutical_Science.rar