Recent advance in hyperspectral sensors and applications

T Fake drugs threatens medical supply chain frightfully over 124 countries in the world. Even in Japan, although nobody expected counterfeits violate the maintained distribution of this country, fake harvoni for hepatitis C sold at an authorized pharmacy shocked officials in Ministry of Health, Labor and Welfare. Anti-counterfeit to prevent fake drugs requires rapid-authenticating, costless, and more than anythings, high-security technology. Recent advances in nanotechnology accelerate developments of nanotag identifiers. Thinking of rapidness and high security in authentication, surface enhanced Raman scattering (SERS) produced from well-designed noble metal nanostructure is promised to apply new authentication method. We have developed SERS active nanostructures by self-assembling of gold nanoparticles (AuNP) with Raman active reporting molecules. A few nanogram amounts of the AuNP assembles were directly deposited onto commercial tablet Mucodyne. For on-dose authentication outside of a laboratory, 80 g weight and smart-phone driven palm-top Raman detector was used. Shelf-life in SERS activity of the AuNP self-assemble liquid stocked at room temperature was over six months. The nanotag labeled Mucodyne tablet showed special SERS signal derived from the reporting molecule, and 0.2 s irradiation of 785 nm (5 mW) laser was enough to produce distinguishable SERS spectra from intact tablet. Excellent longevity of SERS signal over three years on the labeled tablets was confirmed. By just 0.2 second laser irradiation with a palmtop Raman spectrometer, rapid on-dose authentication was successfully achieved.