Module 1: Getting Started

MB 360: Scientific Inquiry in Microbiology At the Bench

Carlos C. Goller, Ph.D.

NC State University | Department of Biological Sciences

Camila Loyola, Graduate Teaching Assistant

2026-08-19

Module 1: Getting Started

MB 360: Scientific Inquiry in Microbiology At the Bench

MB 360 Lab Workbook
NC State University | Department of Biological Sciences

Overview

Week 1 · Lab safety · Pipetting fundamentals · First ELN entries

  • Review Thomas Hall lab-safety rules and personal protective equipment
  • Practice mechanical micropipettes and electronic multichannel pipettes
  • Document results in the Electronic Lab Notebook (ELN)
  • Build a team charter and communication plan

Learning Outcomes

  • List the personal protective equipment needed for MB 360
  • Identify the features of the mechanical pipettes used in the course
  • Explain how streak plating helps dilute bacteria
  • Describe the advantages of electronic and multichannel pipettes
  • Create a lab entry in the ELN system
  • Collect and interpret pipetting data
  • Create a team charter and communication plan

Skills & Knowledge

Skills

  • Follow basic safety precautions with live bacterial organisms
  • Transfer liquid volumes reproducibly with pipettors
  • Document protocols, observations, and results in an ELN
  • Interpret variability in pipetting performance

Knowledge

  • Pipettor types and their volume ranges
  • PPE expectations for microbial work

Lab Safety

Important: Treat all tips as potential biohazards at all times.

  • Before lab: Wear lab coat, goggles, and gloves
  • During lab:
    • Clean the bench before and after each session with 70% ethanol
    • Dispose of cultures and plates using designated biohazard procedures
  • After lab: Remove PPE and decontaminate any personal items touched during lab

Methods: Pipetting Practice

Illustration of a micropipette with the volume display highlighted for reading the setting.

Micropipette volume display for introductory pipetting practice.

  • Add correct volume to each circle — keep drops within the circle
  • Have each group member try at least two different volumes
  • Practice picking up the entire drop without leaving liquid behind

Methods: Volume Challenge

  • Each group member attempts three volumes: 5 µL, 20 µL, and 100 µL
  • Repeat each volume three times and weigh each drop
  • Record mass (mg) in the data table; calculate accuracy and coefficient of variation

Results & Discussion

  • Compare your gravimetric accuracy to the pipette specification (±2%)
  • Identify the volume where your group had the most and least variability
  • Discuss one adjustment you made to improve consistency

Reflection Questions

  1. Why is reproducibility important when setting up 96-well plate assays?
  2. Which pipette type works best for very small volumes (< 2 µL), and why?
  3. What did you include in your first ELN entry, and why does structure matter?