Background: Autoactivation of initiator proteases of complement is a two-step process. Results: Autoactivation and possible cross-activation steps of complement lectin pathway proteases were quantified. Conclusion: Only MASP-1 can autoactivate rapidly, and MASP-2 is activated by MASP-1. Significance: The determined kinetic data are helpful to interpret activation scenarios for the lectin pathway, and the presented strategy can be used to quantify autoactivation of other proteases.

Nanotubes have been extensively utilized as nanocontainers for molecules and as nanoreactors for chemical reactions in confinement, with the potential for applications in hydrogen storage and catalysis. We show that phonon polaritons of boron nitride nanotubes (BNNTs) enhance the near-field vibrational spectra of molecules in close proximity to the surface. By encapsulating C60 fullerene in BNNTs, we reach a sensitivity level of a few hundred molecules. Furthermore, we show by the photopolymerization of C60 that products of chemical reactions inside the tubes can be identified, so long as their vibrational signatures lie in the reststrahlen band of the BNNT.