User:Pranav Rathi/Notebook/OT/2012/10/12/Sample preparation for DNA overstretching & unzipping experiments
The page discusses the protocol we use to prepare DNA-tethering, overstretching and unzipping samples. A standard protocol is same for all three; a specific but similar protocol is adopted depending on the sample and its constituents. I also discuss protocol for sample used to calibrate optical tweezers; stuck and free bead. A standard sample looks like slide.1 in slide-share: It can be single or double chamber. A sample preparation can be divided into two parts: Chamber (single or double) preparation and Tethering-protocol. Sample preparation-procedure discussed here is standard, specific but similar procedure is used depending on the requirements of the sample.
In all my DNA and calibration experiments I use this procedure and it works really well for me. It is simple, quick, versatile and very effective.
Sample preparation
Sample preparation can be divided in chamber preparation and tethering-protocol.
Chamber preparation
A double chamber slide preparation is discussed here with components:
- Slide (by VWR micro slides, cat# 48300-025 [1])
- Cover glass; 18X18mm,.15mm thick (by VWR micro cover glass, cat# 48366-045[2])
- Double sided tape: This is a double sided tape by scotch; cheep but good enough for quality samples.
- Tweezers.
- Roller ( a solid aluminium cylinder to squeezeout the air bubbles between the tape and glass-slide).
- Double razer