Methoxy-X04 is a fluorescent amyloid β (Aβ) probe for the detection and quantification of plaques, tangles and cerebrovascular amyloid with good specificity. It is a derivative of Congo red and Chrysamine-G that contains no acid groups and is therefore smaller and much more lipophilic than Congo red or Chrysamine-G. Methoxy-X04 retains in vitro binding affinity for amyloid beta (Abeta) fibrils (Ki = 26.8 nM) very similar to that of Chrysamine-G. Using multiphoton microscopy to obtain high-resolution (1 microm) fluorescent images from the brains of living PSI/APP mice, individual plaques could be distinguished within 30 to 60 min after a single IV injection or a single IP injection of Methoxy-X04.

How to Use: 

• In vitro:  Methoxy-X04 was used at 50 µM final concentration in various in vitro assays. 
• In vivo: Methoxy-X04 was administered to mice by a single IV injection of 5 to 10 mg/kg or by a single IP injection of 10 mg/kg to produce high contrast images of plaques and cerebrovascular amyloid in PSI/APP mouse brain.

Reference:

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