A properly constituted in vivo microdialysis system includes the following microdialysis instruments: a syringe pump to deliver artificial cerebral spinal fluid (aCSF) to the microdialysis probe. After the sample leaves the probe, it can be collected manually with a single collection tube. However, since a series of fractions will be collected every 5-20 minutes over at least a 4-6 hour period, most researchers prefer to use an automated, refrigerated, 96-well plate fraction collector. You can then use an autoinjector for automated sample collection from the microdialysis system and automated sample injection to the HPLC.