Biomed- Chem

BMS1023 – Laboratory Practical: Biuret Protein Assay & Standard Curve

Practical 3 Report

Student name: Kristen (Kris) Deal

URN : 6326892

Important: The practical reports should be individual work. You will have worked in groups during the laboratory session, thus there is scope for collusion. Use references and cite correctly, as accessed. The practical report should be submitted, using the MS Word proforma provided on SurreyLearn, as a hardcopy to the Exams Office. For further advice, please contact the Module Coordinator, Dr Alfred Thumser.

1. Standard curve […/10]:

BSA Standard Curve: |

Tube number | 1 & 2 | 3 & 4 | 5 & 6 | 7 & 8 | 9 & 10 | 11 & 12 | 13 & 14 |

Final BSA concentration (mg/ml) | 0 | 0.5 | 1 | 2 | 3 | 4 | 5 |

Volume of BSA (5 mg/ml) required (ml) | 0 | 0.1 | 0.2 | 0.4 | 0.6 | 0.8 | 1.0 |

Volume of 0.5M NaOH (ml) | 1.0 | 0.9 | 0.8 | 0.6 | 0.4 | 0.2 | 0 |

Absorbance | -0.004-0.004 | 0.0400.081 | 0.0830.093 | 0.1440.159 | 0.2290.236 | 0.3220.351 | 0.3940.402 |

2. “Unknown” samples (in triplicate) […/10]:

Tube number/Duplicate | 15-17 | 18-20 | 21-23 | 24-26 | 27-29 |

Volume of samples (ml) | 1 ml of A | 1 ml of B | 1 ml of C | 1 ml of D | 1 ml of E |

Absorbance values (triplicates) | 0.3880.3550.343 | 0.0350.0350.037 | 0.2100.1790.225 | 0.0270.0250.021 | 0.2690.2630.250 |

Average | 0.362 | 0.037 | 0.204 | 0.024 | 0.261 |

3. Plot the standard curve on graph paper and fit the data points to a straight line. Include a digital copy of your graph in this report […/20]

4. Calculate the protein concentration of your “unknown” samples […/20]:

Unknown | Absorbance values | Average | Dilution factor | [Protein] (mg/mL] |

A | 0.388 | 0.355 | 0.343 | 0.362 | 0 | 4.75 |

B | 0.035 | 0.035 | 0.037 | 0.037 | *10^-1 | 4.73 |

C | 0.210 | 0.179 | 0.225 | 0.204 | 0 | 2.67 |

D | 0.027 | 0.025 | 0.021 | 0.024 | *10^-1 | 3.03 |

E | 0.269 | 0.263 | 0.250 |...