PCR-Free Hepatitis B Virus Determination by Electrogenerated Chemiluminescence (Awarded with the Best oral presentation award in the field of sensors, instrumentation and multiphysics simulation by MDPI Micromachines)
* Nikolaou 1,* Setralia 2, A. Zanut 1,3, G. Valenti 1, S. Conoci 4, L. Prodi 1 and F. Paolucci 1
* Department of Chemistry \"Giacomo Ciamician\", University of Bologna, Via Selmi 2, 40216 Bologna, Italy
* Dipartimento di Scienze del Farmaco e della Salute, University of Catania, Viale Andrea Doria, 6, 95125 Catania, Italy
* Department of Chemical and Biomolecular Engineering, New York University, 6 Metrotech, Brooklyn, NY 11201 USA
* Dipartimento di Scienze Chimiche, Biologiche, Farmaceutiche ed Ambientali, University of Messina, Viale Ferdinando Stagno d'Alcontres 31, 98168 Messina, Italy
* Correspondence: Pavlos.nikolaou2@unibo.it  
Electrochemiluminescence, or Electrogenerated Chemiluminescence, (ECL) is an electrochemical technique with a simple instrumentation which is based on a luminescent phenomenon, produced from an electron-transfer reaction taking place on the surface of the electrode and yielding light-emitting excited states. The most commonly known luminophores/coreactant system in aqueous media is tris(2,2\({}^{\prime}\)-bipyridine) ruthenium(II) ([Ru(bpy)3]\({}^{2+}\))/tri-n-propylamine, with important analytical application in commercial assays for the detection of biomarkers [1,2]. According to World Health Organization (WHO) Hepatitis B Virus (HBV) is the main problem of the infection of 257 million people [3]. An ECL-based and also PCR-free sensor is developed for the determination of the double-stranded DNA of HBV (ds-DNA). The ds-DNA of HBV has been immobilized and remained anchored between two monoclonal oligonucleotide chains probes (P1 and P2), thus the same time the triplex formation is created via Hoogstern H-bonds (Figure 20, left) [4]. The ECL-active molecule [Ru(phen)\({}_{2}\)dppz]2\({}^{+}\) it can remain intercalated in the ds-DNA according to the \(\pi\)-\(\pi\)\({}^{*}\) stalking intercalation-dppz [5]. The ECL-based sensor is tested in a range from 0-10,000 copies \(\mu\)L\({}^{-1}\) obtaining a limit of detection of 2.7 copies \(\mu\)L\({}^{-1}\) which is much more sensitive in comparison with other techniques. ## References  
* _Zanut et al. (2019)_ Zanut, A.; Fiorani, A.; Rebeccani, S.; Kesarkar, S.; Valenti, G. Electrochemiluminescence as emerging microscopy techniques. _Anal. Bioanal. Chem._**2019**, _411_, 4375-4382. * _Zanut et al. (2020)_ Zanut, A.; Fiorani, A.; Saito, T.; Ziebart, N.; Rebeccani, S.; Barbon, A.; Irie, T.; Josel, H.; Negri, F.; Marcaccio, M.; et al. Insights into the mechanism of coreact electrochemical luminescence facilitating enhanced bioanalytical performance. _Nat. Commun._**2020**, _11_, 2668-2676. * World Health Organization (WHO). _Global Health Sector Strategy on Viral Hepatitis;_ World Health Organization: Geneva, Switzerland, 2016. * _Petrala et al. (2020)_ Petralia, S.; Forte, G.; Zimbone, M.; Conoci, S. The cooperative interaction of triplex forming oligonucleotides on DNA-triplex formation at electrode surface: Molecular dynamics studies and experimental evidences. _Colloids Surf. B Biointerfaces_**2020**, _187_, 110648. * _He et al. (2015)_ He, Y.; Li, J.; Liu, Y. Reusable and dual-potential responses electrogenerated chemiluminescence biosensor for synchronously cytosensing and dynamic cell surface N-glycan evaluation. _Anal. Chem._**2015**, _87_, 9777-9785. * _14.4. Sensitive Voltammetric Approaches for the Total Isopropylmethylphenols Quantification in Plant Material_
* _G. Ziyatdinova_* _and_ N. Chermousova_  
Analytical Chemistry Department, Kazan Federal University, Kremleyevskaya, 18, 420008 Kazan, Russia
* Correspondence: Ziyatdinovag@mail.ru  
Isopropylmethylphenols (carvacrol and thymol) are a natural phenolic monoter-penoids isolated from aromatic plants _Origanum vulgare, Thymus vulgaris, Lepidium flavour,_ and _Citrus aurantium bergamia_, etc. [1].