Optiscience have just released their new ACM-200plus Anthocyanin content meter.
The ACM-200plus provides fast, reliable, non-destructive anthocyanin content measurement of intact leaves.
References: van den Berg A.K., Perkins T.D. (2005)
Nondestructive Estimation of Anthocyanin Content in Autumn Sugar Maple Leaves
HortScience 40(3):685-686. 2005
Morris J.B., Wang M.L. (2007)
Anthocyanin and Potential Therapeutic Traits in Clitoria, Desmodium, Catharanthus and Hibiscus Species Acta Hort. 756, ISHS 2007
For a .pdf copy of the brochure see http://www.adc.co.uk/bmt_mymedia/files/CCM200Aplus.pdf