We show that meta-antennas made of a composite material displaying type II hyperbolic dispersion enable precise and controlled spectral separation of absorption and scattering processes in the visible/near-infrared frequency range. The experimental evidence is supported by a comprehensive theoretical study. We demonstrate that the physical mechanism responsible for the aforementioned effect lies in the different natures of the plasmonic modes excited within the hyperbolic meta-antennas. We prove that it is possible to have a pure scattering channel if an electric dipolar mode is induced, while a pure absorption process can be obtained if a magnetic dipole is excited. Also, by varying the geometry of the system, the relative weight of scattering and absorption can be tuned, thus enabling an arbitrary control of the decay channels. Importantly, both modes can be efficiently excited by direct coupling with the far-field radiation, even when the radiative channel (scattering) is almost totally suppressed, hence making the proposed architecture suitable for practical applications. E 0 k n = 1.5 n = 1.5 J J J J n= 1.5  = 860 nm  = 1120 nm  = 1100 nm  = 1300 nm  = 860 nm  = 1120 nm  = 1100 nm  = 1300 nm APPENDIX A: NUMERICAL SIMULATIONS AND THEORETICAL ANALYSIS 1. Optimization of the hyperbolic meta-antennas dimensions and composition

Continuous 295 nm excitation of whey protein bovine apo-α-lactalbumin (apo-bLA) results in an increase of tryptophan fluorescence emission intensity, in a progressive red-shift of tryptophan fluorescence emission, and breakage of disulphide bridges (SS), yielding free thiol groups. The increase in fluorescence emission intensity upon continuous UV-excitation is correlated with the increase in concentration of free thiol groups in apo-bLA. UV-excitation and consequent SS breakage induce conformational changes on apo-bLA molecules, which after prolonged illumination display molten globule spectral features. The rate of tryptophan fluorescence emission intensity increase at 340 nm with excitation time increases with temperature in the interval 9.3-29.9°C. The temperature-dependent 340 nm emission kinetic traces were fitted by a 1st order reaction model. Native apo-bLA molecules with intact SS bonds and low tryptophan emission intensity are gradually converted upon excitation into apo-bLA molecules with disrupted SS, molten-globule-like conformation, high tryptophan emission intensity and red-shifted tryptophan emission. Experimental Ahrrenius activation energy was 21.8 ± 2.3 kJ x mol(-1). Data suggests that tryptophan photoionization from the S(1) state is the likely pathway leading to photolysis of SS in apo-bLA. Photoionization mechanism(s) of tryptophan in proteins and in solution and the activation energy of tryptophan photoionization from S(1) leading to SS disruption in proteins are discussed. The observations present in this paper raise concern regarding UV-light pasteurization of milk products. Though UV-light pasteurization is a faster and cheaper method than traditional thermal denaturation, it may also lead to loss of structure and functionality of milk proteins.

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Patulin is a toxic secondary metabolite of a number of fungal species belonging to the genera Penicillum and Aspergillus. It has been mainly isolated from apples and apple products contaminated with the common storage-rot fungus of apples, Penicillum expansum, but it has also been extracted from rotten fruits, moldy feeds, and stored cheese. Human exposure to patulin can lead to serious health problems, and according to a long-term investigation in rats, the World Health Organization has set a tolerable weekly intake of 7 ppb body weight. The content of patulin in foods has been restricted to 50 ppb in many countries. Conventional analytical detection methods involve chromatographic analyses, such as HPLC, GC, and, more recently, techniques such as LC/MS and GC/MS. However, extensive protocols of sample cleanup are required prior to the analysis, and to accomplish it, expensive analytical instrumentation is necessary. An immunochemical analytical method, based on highly specific antigen-antibody interactions, would be desirable, offering several advantages compared to conventional techniques, i.e., low cost per sample, high selectivity, high sensitivity, and high throughput. In this paper, the synthesis of two new derivatives of patulin is described, along with their conjugation to the bovine serum albumin for the production of polyclonal antibodies. Finally, a fluorescence competitive immunoassay was developed for the on-line detection of patulin.

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