My LC lids are designed to aseptically aspirate the liquid cultures via a syringe without a needle, while incorporating a filter membrane to allow gas exchange. I have found that large gauge needles tend to cut chunks out of inoculation ports, real rubber ports and also diy silicone ports. I have seen large chunks of red rubber floating inside of my LC jars and syringes after aspiration many times. This is an obvious vector of contamination. By skipping the port we can beat this issue while also gaining some major convenience. My lids revolve around a neat little part I found, it is a polypropylene male/female luer lock plug. This plug can be used as is as a luer lock cap, or using a heated nail you can burn out the middle and it becomes a luer lock bulkhead adapter. My lids consist of these main parts:
- Plastic Storage Lid
- Silicone Ring
- 3x PP M/F Luer plugs, 2 opened up with a heated nail and 1 unmolested
- 1x Syringe Filter, PP Membrane .22 micron 13mm
- Drill 2 5mm holes in your lid 10mm from the edge, opposite each other.
- Use sandpaper to rough up the area around both holes on both sides of the lid.
- Use pliers or drill press to hold 10d nail, heat with torch, wait a few seconds, plunge through 2 of your PP luer plugs to open it up.
- Feed the 2x moddified luer plugs into the holes, one male up and one female up.
- Carefully using permatex clear silicone (red is too soft, the ports will fall off) seal the 2 luer ports to the lid with a neat bead, top and bottom.
- Allow 24 hours to cure.
- Place silicone ring onto underside of plastic lid and plug the female luer lock port with the unmolested plug.
Personally I PC the LC with the syringe filter removed in its own separate foil pack, covering the male port with a small piece of foil and cooling the cycle in a flowhood before attaching the filter. This is unnecessary but I figure the filter will last much longer without having a bunch of hot sugar vapor blasting through it each pressure cooker cycle.
The cap protects the female port, keeping it completely sterile. When you are ready to aspirate, in a flowhood or still air box remove the plug, attach syringe, tilt, suck, replace plug.
Edited by sandman, 20 April 2017 - 06:49 PM.