Vol. 07: Home Molecular Genetics

Extract, fingerprint, and replicate your own DNA.



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Sensor Subcircuit Schematic

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Thermal Cycler Schematic

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Full Materials List

PROJECT 1 MATERIALS:

  • A Narrow Transparent container (something test tube like that can hold 10mls, like those medicine feeding syringes you can get for pets or small children)
  • Table Salt
  • Baking Soda
  • Bottled Water
  • Paper Cup
  • Liquid Soap (preferably non-colored, non scented)
  • Rubbing Alcohol (99% variety - Isopropanol, sometimes called 2-propanol)
  • Agar agar: This is a common food thickener found in oriental grocery stores. Choose the powdered form that does not contain any additional ingredients (such as glucose).
  • Aquarium pH kit
  • Wooden Toothpicks
  • Lego
  • 9V batteries
  • Stainless steel screws (5mm)
  • Stainless steel wire (20 gauge) or better electrical wiring
  • Lego
  • Plastic containers
  • Glycerine/Glycerol (pharmacy shelves)
  • Red Food Coloring (Club House brand works well; some other brands won't)
  • Methylene Blue (aquarium antimicrobial)

PROJECT 2 MATERIALS:

  • Peltier Device
  • Aluminum block
  • Heat sink
  • Thermal paste
  • Nylon screws (prevents heat conduction)
  • Power supply
  • HandyBoard microcontroller module
  • Breadboard
  • Small DC fan (MOSFETs can get hot!)
  • Wire, solid-core
  • Header pins

SCHEMATIC COMPONENTS:


U1		Op-amp chip (OPA 4241PA, Burr-Brown)
U1		Op-amp chip (OPA 4241PA, Burr-Brown)
R		resistor, 10 kohm
R2		resistor, 33 kohm 
POT		potentiometer, 10 kohm 
U2		comparator (LM311, National)
3904, 3906	Bipolar Junction Transistors
IRF5305	MOSFET, P-Channel enhancement
HUF75321 	MOSFET, N-Channel enhancement

Revised Illustration

The batteries shown in the "Gel Box" illustration on page 67 of Volume 07 are shown connected in parallel. The text, however, explains setting the batteries up in series. Setting the batteries up in parallel will push the DNA through more slowly, so we recommend setting them up in series, as stated in the text of the article and shown here:

Revised illustration.

MAKE: AMENDS Errata for This Article

 !

Correction for page 69
In the diagram on p. 69, mineral oil only surrounds the reaction tube; the PCR reaction mix inside the tube is a water-based solution. See http://scq.ubc.ca/MAKE for a full discussion of the project.


 !

Correction for page 67
On p. 67, "Prepare the DNA," the amount of running buffer should read "75 µl (3 droplets)." In "Stain the Gel," the dilution ratio for 2.3% Methylene Blue should be 115:1.


 !

Correction for page 66
The batteries shown in the "Gel Box" illustration on page 67 of Volume 07 are shown connected in parallel. The text, however, explains setting the batteries up in series. Setting the batteries up in parallel will push the DNA through more slowly, so we recommend setting them up in series, as stated in the text of the article. Here's a revised illustration.


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