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Department of Nanotechnology

Head of the department prof., habil.. dr. Arūnas Ramanavičius  
Phone +370 5 2619532
 

The Department of Nanotechnology conducts a wide range of research in the field of biological sensors. 

One of these areas is the development of optical biological sensors. Spectroscopic ellipsometry, surface plasmon resonance, and spectroscopic ellipsometry enhanced with surface plasmon resonance techniques are used for this purpose. The optical properties of various substrates intended for use in biosensors are determined during the research. For this purpose, different substrates such as nanolaminates are used, consisting of repeating bilayers of metal oxides with different thicknesses. By choosing the required number of bilayers and the thicknesses of individual layers, it is possible to obtain the coatings required for optical sensors with specific optical properties. Materials such as Al2O3/ZnO, Al2O3/TiO2, and ZnO/GOx bilayers are used in nanolaminates. Also, nanowires formed from ZnO and TiO2 coating or metal layers are used to create optical biological sensors to excite surface plasmon waves. After carrying out the necessary tests on the pallets, they are further modified with biological layers formed from different proteins or enzymes. The kinetics of the formation of these layers can be analyzed in real-time using the spectroscopic ellipsometry technique. After measuring the kinetics, various analytical and numerical modelling methods are further applied to calculate the kinetic parameters and reveal the mechanisms of the formation of molecular layers and their interactions with other proteins. 

Another topic of research carried out in the Department of Nanotechnology is electrochemical research using electrically conductive polymers as research objects. Conductive polymers such as polypyrrole (Ppy) and its derivatives, polyaniline (PANI) and its derivatives, poly(3, 4-ethylenedioxythiophene) (PEDOT) are used for research. Also investigated are copolymers obtained by electrochemical polymerization of the mentioned monomers. The main directions of research of these polymers are studies of electrochromic properties, application of molecular imprint polymers in the production of sensors for the determination of small molecular compounds in solutions, etc. 

The nanotechnology department creates and analyzes several different types of biofuel cell systems. We focus on enzymatic (Glucose oxidase, horseradish peroxidase-based) and microorganism (Yeast, aerobic and anaerobic bacteria-based) biofuel cell systems that operate in a single chamber or in multi-chamber configurations. With the intent to be used for energy production in off-grid installations and waste treatment applications.

Laboratories:


MOST IMPORTANT PUBLICATIONS
  1. Bogužaitė, Raimonda; Pilvenytė, Greta; Ratautaitė, Vilma; Brazys, Ernestas; Ramanavičienė, Almira; Ramanavičius, Arūnas. Towards molecularly imprinted polypyrrole-based sensor for the detection of methylene blue // Chemosensors. eISSN 2227-9040. 2023, vol. 11, iss. 11, art. no. 549, p. 1-13.
  2. Reinikovaitė, Viktorija; Matulevičius, Matas; Elsakova, Alexandra; Drobysh, Maryia; Liustrovaitė, Viktorija; Lukša, Algirdas; Jafarov, Ali; Slibinskas, Rimantas; Ramanavičius, Arūnas; Baradokė, Aušra. Electrochemical capacitance spectroscopy based determination of antibodies against SARS-CoV-2 virus spike protein // Science of the total environment. ISSN 0048-9697. 2023, vol. 903, art. no. 166447, p. 1-7.
  3. Petrulevičienė, Milda; Savickaja, Irena; Juodkazytė, Jurga; Ramanavičius, Arūnas. Investigation of WO3 and BiVO4 photoanodes for photoelectrochemical sensing of xylene, toluene and methanol // Chemosensors. eISSN 2227-9040. 2023, vol. 11, iss. 11, art. no. 552, p. 1-14
  4. Petrulevičienė, Milda; Turuta, Kamila; Savickaja, Irena; Juodkazytė, Jurga; Ramanavičius, Arūnas. Photoelectrochemical degradation of organic compounds via formed reactive chlorine and sulfate species by WO3-based photoanodes // Journal of electroanalytical chemistry. ISSN 1572-6657. 2023, vol. 951, art. no. 117954, p. 1-10.
  5. Elsakova, Alexandra; Merzlikin, Mark; Jafarov, Ali; Zilinskaite, Nemira; Sulciute, Agne; Baradoke, Ausra. Examination of non-modified carbon fibre bundle as an electrode for electrochemical sensing//Coatings. ISSN 2079-6412. 2023, vol. 13, iss. 8, art. no. 1372, p. 1-15.
  6. Morkvėnaitė-Vilkončienė, Inga; Kisieliūtė, Aura; Nogala, Wojciech; Popov, Anton; Brasiūnas, Benediktas; Kamarauskas, Mindaugas; Ramanavičius, Arūnas; Linfield, Steven; Ramanavičienė, Almira. Scanning electrochemical microscopy: Glucose oxidase as an electrochemical label in sandwich format immunoassay//Electrochimica acta. ISSN 0013-4686. 2023, vol. 463, art. no. 142790, p. 1-8.
  7. Plikusienė, Ieva; Mačiulis, Vincentas Mindaugas; Juciutė, Silvija; Ramanavičius, Arūnas; Ramanavičienė, Almira. Study of SARS-CoV-2 spike protein wild-type and the variants of concern real-time interactions with monoclonal antibodies and convalescent human serum//Biosensors. eISSN 2079-6374. 2023, vol. 13, no. 8, art. no. 784, p. 1-8.
  8. Plikusienė, Ieva; Mačiulis, Vincentas Mindaugas; Vertelis, Vilius; Juciutė, Silvija; Balevičius, Saulius; Ramanavičius, Arūnas; Talbot, Julian; Ramanavičienė, Almira. Revealing the SARS-CoV-2 spike protein and specific antibody immune complex formation mechanism for precise evaluation of antibody affinity//International journal of molecular sciences. ISSN 1661-6596. 2023, vol. 24, iss. 17, art. no. 13220, p. 1-15.
  9. Kasputė, Greta; Arunagiri, Bharani Dharan; Alexander, Rakshana; Ramanavičius, Arūnas; Samukaitė-Bubnienė, Urtė. Development of essential oil delivery systems by ‘click chemistry’ methods: possible ways to manage Duchenne Muscular Dystrophy//Materials. eISSN 1996-1944. 2023, vol. 16, iss. 19, art. no. 6537, p. 1-20.
  10. Pilvenytė, Greta; Ratautaitė, Vilma; Bogužaitė, Raimonda; Ramanavičius, Arūnas; Viter, Roman; Ramanavičius, Simonas. Molecularly imprinted polymers for the determination of cancer biomarkers // International journal of molecular sciences. ISSN 1661-6596. 2023, vol. 24, iss. 4, art. no. 4105, p. 1-14.
  11. Pilvenytė, Greta; Ratautaitė, Vilma; Bogužaitė, Raimonda; Samukaitė-Bubnienė, Urtė; Plaušinaitis, Deivis; Ramanavičienė, Almira; Bechelany, Mikhael; Ramanavičius, Arūnas. Molecularly imprinted polymers for the recognition of biomarkers of certain neurodegenerative diseases // Journal of pharmaceutical and biomedical analysis. ISSN 0731-7085. 2023, vol. 228, art. no. 115343, p. 1-10.
  12. Liustrovaitė, Viktorija; Pogorielov, Maksym; Bogužaitė, Raimonda; Ratautaitė, Vilma; Ramanavičienė, Almira; Pilvenytė, Greta; Holubnycha, Viktoriia; Korniienko, Viktoriia; Diedkova, Kateryna; Viter, Roman; Ramanavičius, Arūnas. Towards electrochemical sensor based on molecularly imprinted polypyrrole for the detection of bacteria-Listeria monocytogenes // Polymers. eISSN 2073-4360. 2023, vol. 15, iss. 7, art. no. 1597, p. 1-16.
  13. Andriukonis, Eivydas; Butkevičius, Marius; Šimonis, Povilas; Ramanavičius, Arūnas. Development of a disposable polyacrylamide hydrogel-based semipermeable membrane for micro Ag/AgCl reference electrode // Sensors. ISSN 1424-8220. 2023, vol. 23, iss. 5, art. no. 2510, p. 1-10.
  14. Bironaitė, Daiva; Petronienė, Jūratė Jolanta; Miksiunas, Rokas; Zinovičius, Antanas; Morkvėnaitė-Vilkončienė, Inga; Ramanavičius, Arūnas. Scanning electrochemical microscopy for the stimulation and investigation of human skeletal muscle-derived mesenchymal stem/stromal cells // Electrochimica acta. ISSN 0013-4686. 2023, vol. 455, art. no. 142389, p. 1-9.
  15. Pilvenytė, Greta; Ratautaitė, Vilma; Bogužaitė, Raimonda; Ramanavičius, Simonas; Chen, Chien-Fu; Viter, Roman; Ramanavičius, Arūnas. Molecularly imprinted polymer-based electrochemical sensors for the diagnosis of infectious diseases // Biosensors. eISSN 2079-6374. 2023, vol. 13, iss. 6, art.no. 620, p. 1-28.
  16. Ratautaitė, Vilma; Bogužaitė, Raimonda; Brazys, Ernestas; Plaušinaitis, Deivis; Ramanavičius, Simonas; Samukaitė-Bubnienė, Urtė; Bechelany, Mikhael; Ramanavičius, Arūnas. Evaluation of the interaction between SARS-CoV-2 spike glycoproteins and the molecularly imprinted polypyrrole // Talanta. ISSN 0039-9140. 2023, vol. 253, art. no. 123981, p. 1-9.
  17. Žukauskas, Šarūnas; Ručinskienė, Alma; Ratautaitė, Vilma; Ramanavičienė, Almira; Pilvenytė, Greta; Bechelany, Mikhael; Ramanavičius, Arūnas. Electrochemical biosensor for the determination of specific antibodies against SARS-CoV-2 spike protein // International journal of molecular sciences. eISSN 1422-0067. 2023, vol. 24, iss. 1, art. no. 718, p. 1-14.
  18. Reinikovaitė, Viktorija; Žukauskas, Šarūnas; Žalnėravičius, Rokas; Ratautaitė, Vilma; Ramanavičius, Simonas; Bučinskas, Vytautas; Vilkienė, Monika; Ramanavičius, Arūnas; Samukaitė-Bubnienė, Urtė. Assessment of Rhizobium anhuiense bacteria as a potential biocatalyst for microbial biofuel cell design // Biosensors. eISSN 2079-6374. 2023, vol. 13, iss. 1, art. no 66, p. 1-12.
  19. Kižys, Kasparas; Zinovičius, Antanas; Jakštys, Baltramiejus; Bružaitė, Ingrida; Balčiūnas, Evaldas; Petrulevičienė, Milda; Ramanavičius, Arūnas; Morkvėnaitė-Vilkončienė, Inga. Microbial biofuel cells: Fundamental principles, development and recent obstacles // Biosensors. eISSN 2079-6374. 2023, vol. 13, iss. 2, art. no. 221, p. 1-16.
  20. Drobysh, Maryia; Ramanavičius, Arūnas; Baradokė, Aušra. Polyaniline-based electrochemical immunosensor for the determination of antibodies against SARS-CoV-2 spike protein // Science of the total environment. ISSN 0048-9697. 2023, vol. 862, art. no. 160700, p. 1-9.
  21. Žalnėravičius, Rokas; Pakštas, Vidas; Grincienė, Giedrė; Klimas, Vaclovas; Paškevičius, Algimantas; Timmo, Kristi; Kauk-Kuusik, Marit; Franckevičius, Marius; Niaura, Gediminas; Talaikis, Martynas; Jagminas, Arūnas; Ramanavičius, Arūnas. Antimicrobial particles based on Cu2ZnSnS4 monograins // Colloids and surfaces B: Biointerfaces. ISSN 0927-7765. 2023, vol. 225, art. no. 113275, p. 1-11.
  22. Petrulevičienė, Milda; Savickaja, Irena; Juodkazytė, Jurga; Grincienė, Giedrė; Ramanavičius, Arūnas. Investigation of BiVO4-based advanced oxidation system for decomposition of organic compounds and production of reactive sulfate species // Science of the total environment. ISSN 0048-9697. 2023, vol. 875, art. no. 162574, p. 1-10.
  23. Ramanavičius, Simonas; Samukaitė-Bubnienė, Urtė; Ratautaitė, Vilma; Bechelany, Mikhael; Ramanavičius, Arūnas. Electrochemical molecularly imprinted polymer based sensors for pharmaceutical and biomedical applications (review) // Journal of pharmaceutical and biomedical analysis. ISSN 0731-7085. 2022, vol. 215, art. no. 114739, p. 1-12.
  24. Drobysh, Maryia; Liustrovaitė, Viktorija; Baradokė, Aušra; Viter, Roman; Chen, Chien-Fu; Ramanavičius, Arūnas; Ramanavičienė, Almira. Determination of rSpike protein by specific antibodies with screen-printed carbon electrode modified by electrodeposited gold nanostructures // Biosensors. eISSN 2079-6374. 2022, vol. 12, no. 8, art. no. 593, p. 1-16.
  25. Šlekienė, Nora; Snitka, Valentinas; Bružaitė, Ingrida; Ramanavičius, Arūnas. Influence of TiO2 and ZnO nanoparticles on α-Synuclein and β-Amyloid aggregation and formation of protein fibrils // Materials. ISSN 1996-1944. 2022, vol. 15, iss. 21, art. no. 7664, p. 1-18.
  26. Andriukonis, Eivydas; Reinikovaitė, Viktorija; Ramanavičius, Arūnas. Comparative study of polydopamine and polypyrrole modified yeast cells applied in biofuel cell design // Sustainable energy and fuels. ISSN 2398-4902. 2022, vol. 6, iss. 18, p. 4209-4217.
  27. Dronina, Julija; Plaušinaitis, Deivis; Samukaitė-Bubnienė, Urtė; Ramanavičius, Arūnas. Real-time label-free assessment of T7 DNA polymerase immobilization // Materials today nano. ISSN 2588-8420. 2022, vol. 19, art. no. 100232, p. 1-8.
  28. Ratautaitė, Vilma; Brazys, Ernestas; Ramanavičienė, Almira; Ramanavičius, Arūnas. Electrochemical sensors based on l-tryptophan molecularly imprinted polypyrrole and polyaniline // Journal of electroanalytical chemistry. ISSN 1572-6657. 2022, vol. 917, art. no. 116389, p. 1-10.
  29. Poderytė, Margarita; Valiūnienė, Aušra; Ramanavičius, Arūnas. Scanning electrochemical microscope as a tool for the electroporation of living yeast cells // Biosensors and bioelectronics. ISSN 0956-5663.  2022, vol. 205, art. no. 114096, p. 1-8.
  30. Plikusienė, Ieva; Mačiulis, Vincentas Mindaugas; Ramanavičius, Arūnas; Ramanavičienė, Almira. Spectroscopic ellipsometry and quartz crystal microbalance with dissipation for the assessment of polymer layers and for the application in biosensing // Polymers. eISSN 2073-4360. 2022, vol. 14, no. 5, art. no. 1056, p. 1-21.
  31. Dronina, Julija; Samukaitė-Bubnienė, Urtė; Ramanavičius, Arūnas. Towards application of CRISPR-Cas12a in the design of modern viral DNA detection tools (Review) // Journal of nanobiotechnology. ISSN 1477-3155. 2022, vol. 20, art. no. 41, p. 1-15.
  32. Balčiūnas, Domas; Plaušinaitis, Deivis; Ratautaitė, Vilma; Ramanavičienė, Almira; Ramanavičius, Arūnas. Towards electrochemical surface plasmon resonance sensor based on the molecularly imprinted polypyrrole for glyphosate sensing // Talanta. ISSN 0039-9140. 2022, vol. 241, art. no. 123252, p. 1-11.
  33. Samukaitė-Bubnienė, Urtė; Ratautaitė, Vilma; Ramanavičius, Arūnas; Bučinskas, Vytautas. Conducting polymers for the design of tactile sens // Polymers. eISSN 2073-4360. 2022, vol. 14, iss. 15, art. no. 2984, p. 1-20.
  34. Plikusienė, Ieva; Mačiulis, Vincentas; Juciutė, Silvija; Maciulevičienė, Rūta; Balevičius, Saulius; Ramanavičius, Arūnas; Ramanavičienė, Almira. Investigation and comparison of specific antibodies' affinity interaction with SARS-CoV-2 wild-type, B.1.1.7, and B.1.351 spike protein by total internal reflection ellipsometry // Biosensors. ISSN 2079-6374. 2022, vol. 12, iss. 5, art. no. 351, p. 1-12.
  35. Batiuskaite, Danute; Bruzaite, Ingrida; Snitka, Valentinas; Ramanavicius, Arunas. Assessment of TiO2 nanoparticle impact on surface morphology of Chinese hamster ovary cells // Materials. ISSN 1996-1944. 2022, vol. 15, iss. 13, art. no. 4570, p. 1-13.
  36. Liustrovaitė, Viktorija; Drobysh, Maryia; Ručinskienė, Alma; Baradokė, Aušra; Ramanavičienė, Almira; Plikusienė, Ieva; Samukaitė-Bubnienė, Urtė; Viter, Roman; Chen, Chien-Fu; Ramanavičius, Arūnas. Towards an electrochemical immunosensor for the detection of antibodies against SARS-CoV-2 spike protein // Journal of The Electrochemical Society. ISSN 0013-4651. 2022, vol. 169, iss. 3, art. no. 037523, p. 1-7.
  37. Plikusienė, Ieva; Mačiulis, Vincentas Mindaugas; Juciutė, Silvija; Ramanavičius, Arūnas; Balevičius, Zigmas; Slibinskas, Rimantas; Kučinskaitė-Kodzė, Indrė; Simanavičius, Martynas; Balevičius, Saulius; Ramanavičienė, Almira. Investigation of SARS-CoV-2 nucleocapsid protein interaction with a specific antibody by combined spectroscopic ellipsometry and quartz crystal microbalance with dissipation // Journal of colloid and interface science. ISSN 0021-9797. 2022, vol. 626, p. 113-122.
  38. Bužavaitė-Vertelienė, Ernesta; Mačiulis, Vincentas Mindaugas; Anulytė, Justina; Tolenis, Tomas; Baškys, Algirdas; Plikusienė, Ieva; Balevičius, Zigmas. Total internal reflection ellipsometry approach for bloch surface waves biosensing applications // Biosensors. ISSN 2079-6374. 2022, vol. 12, iss. 8, art. no. 584.
  39. Žalnėravičius, Rokas; Ramanavičius, Arūnas. Enhancement of glucose oxidase-based bioanode performance by comprising Spirulina platensis microalgae lysate // Journal of the electrochemical society. ISSN 0013-4651. 2022, vol. 169, iss. 5, art. no. 053510, p. 1-9.
  40. Žalnėravičius, Rokas; Klimas, Vaclovas; Naujokaitis, Arnas; Jagminas, Arūnas; Ramanavičius, Arūnas. Development of biofuel cell based on anode modified by glucose oxidase, Spirulina platensis-based lysate and multi-walled carbon nanotubes // Electrochimica acta. ISSN 0013-4686. 2022, vol. 426, art. no. 140689, p. 1-11.
  41. Drobysh, Maryia; Liustrovaitė, Viktorija; Baradokė, Aušra; Ručinskienė, Alma; Ramanavičienė, Almira; Ratautaitė, Vilma; Viter, Roman; Chen, Chien-Fu; Plikusienė, Ieva; Samukaitė-Bubnienė, Urtė; Slibinskas, Rimantas; Čiplys, Evaldas; Simanavičius, Martynas; Žvirblienė, Aurelija; Kučinskaitė-Kodzė, Indrė; Ramanavičius, Arūnas. Electrochemical determination of interaction between SARS-CoV-2 spike protein and specific antibodies // International Journal of Molecular Sciences. ISSN 1661-6596. 2022, vol. 23, iss. 12, art. no. 6768, p. 1-10.
  42. Badokas, Kazimieras; Kadys, Arūnas; Augulis, Dominykas; Mickevičius, Jūras; Ignatjev, Ilja; Skapas, Martynas; Šebeka, Benjaminas; Juška, Giedrius; Malinauskas, Tadas. MOVPE growth of GaN via graphene layers on GaN/sapphire templates // Nanomaterials. ISSN 2079-4991. 2022, vol. 12, iss. 5, art. no. 785, p. 1-10.
  43. Drobysh, Maryia; Ramanavičienė, Almira; Viter, Roman; Chen, Chien-Fu; Samukaitė-Bubnienė, Urtė; Ratautaitė, Vilma; Ramanavičius, Arūnas. Biosensors for the determination of SARS-CoV-2 virus and diagnosis of COVID-19 infection // International journal of molecular sciences. ISSN 1422-0067. 2022, vol. 23, iss. 2, art. no. 666, p. 1-28.
  44. Ratautaitė, Vilma; Bogužaitė, Raimonda; Brazys, Ernestas; Ramanavičienė, Almira; Čiplys, Evaldas; Juozapaitis, Mindaugas; Slibinskas, Rimantas; Bechelany, Mikhael; Ramanavičius, Arūnas. Molecularly imprinted polypyrrole based sensor for the detection of SARS-CoV-2 spike glycoprotein // Electrochimica acta. ISSN 0013-4686. 2022, vol. 403, art. no. 139581, p. 1-7.
  45. Ramanavičius, Simonas; Morkvėnaitė-Vilkončienė, Inga; Samukaitė-Bubnienė, Urtė; Ratautaitė, Vilma; Plikusienė, Ieva; Viter, Roman; Ramanavičius, Arūnas. Electrochemically deposited molecularly imprinted polymer-based sensors // Sensors. ISSN 1424-8220. 2022, vol. 22, iss. 3, art. no. 1282, p. 1-22.
  46. Zinovičius, Antanas; Rožėnė, Justė; Merkelis, Timas; Bružaitė, Ingrida; Ramanavičius, Arūnas; Morkvėnaitė-Vilkončienė, Inga. Evaluation of a yeast–polypyrrole biocomposite used in microbial fuel cells. Sensors // eISSN 1424-8220. 2022, vol. 22, iss.1, art. no. 327, p. 1-12.
  47. Žalnėravičius, Rokas; Paškevičius, Algimantas; Samukaitė-Bubnienė, Urtė; Ramanavičius, Simonas; Vilkienė, Monika; Mockevičienė, Ieva; Ramanavičius, Arūnas. Microbial fuel cell based on nitrogen-fixing Rhizobium anhuiense bacteria // Biosensors. eISSN 2079-6374. 2022, vol. 12, iss. 2, art. no. 113, p. 1-15.
  48. Petrulevičienė, Milda; Juodkazytė, Jurga; Savickaja, Irena; Karpič, Renata; Morkvėnaitė-Vilkončienė, Inga; Ramanavičius, Arūnas. BiVO4-based coatings for non-enzymatic photoelectrochemical glucose determination // Journal of electroanalytical chemistry. ISSN 1572-6657. 2022, vol. 918, art. no. 116446, p. 1-28.
ACHIEVEMENTS, AWARDS OF DEPARTMENT EMPLOYEES
  • Dr Ieva Plikusiene, Biosensors 2021 Early-career Women award, MDPI, Basel 2022.
  • Dr Ieva Plikusiene has been recognized as the 2022 L‘Oréal-Unesco international rising talent (https://www.unesco.org/en/prizes/women-science/)
  • October 14, 2022, International Scientific Conference Chemistry and Chemical Technologies 2022 took place, where Vincentas Mindaugas Mačiulis' oral presentation „Study of SARS-CoV-2 nucleocapsid protein and specific antibodies interaction by combined optical and acoustic methods” was awarded as the best oral presentation in Biochemistry and environmental chemistry (https://cct-conference.ktu.edu).
  • October 19 – 20, 2022 The 12th FizTech2022 conference of PhD students and young scientists of the Center for Physical and Technological Sciences (FTMC) took place, where Raimonda Bogužaitė's "Electrochemical Deposition and Modifications of Polypyrrole with Methylene Blue" and Vincentas Mindaugas Mačiulis' "SARS-CoV-2 nucleocapsid protein immune complex investigation by combined acoustic and optical methods" oral presentations as winners of the best oral presentations (https://www.ftmc.lt/news/1192/69/Doktorantu-ir-jaunuju-mokslininku-konferencija-FizTech2022 ).
OVERVIEW OF PUBLICATIONS, 2022
Spectroscopic Ellipsometry and Quartz Crystal Microbalance with Dissipation for the Assessment of Polymer Layers and for the Application in the Biosensing

I. Plikusiene, V. Maciulis, A. Ramanavicius, A. Ramanaviciene, Spectroscopic Ellipsometry and Quartz Crystal Microbalance with Dissipation for the Assessment of Polymer Layers and for the Application in Biosensing, Polymers, 14 (2022) 1056. https://doi.org/10.3390/polym14051056

Polymers represent materials that are applied in almost all areas of modern life, therefore, the characterization of polymer layers using different methods is of great importance. In this review, the main attention is dedicated to the non-invasive and label-free optical and acoustic methods, namely spectroscopic ellipsometry (SE) and quartz crystal microbalance with dissipation (QCM-D). The specific advantages of these techniques applied for in situ monitoring of polymer layer formation and characterization, biomolecule immobilization, and registration of specific interactions were summarized and discussed.


Figure 1. Scheme of optical Spectroscopic Ellipsometry and acoustic Quartz Crystal Microbalance with Dissipation signals detection in presence of a thin polymer layer on top of the sensor.

 
Real-time label-free assessment of T7 DNA polymerase immobilization
J. Dronina, D. Plausinaitis, U. Samukaite-Bubniene, A. Ramanavicius, Real-time label-free assessment of T7 DNA polymerase immobilization, Materials Today Nano, 19 (2022) 100232. https://doi.org/10.1016/j.mtnano.2022.100232
Immobilization of DNA-modifying enzymes on any surface is still a complex and challenging task in biotechnology and biosensorics. Therefore, this task very often is crucial, especially in biosensors dedicated to the continuous monitoring of DNA. The novelty and the importance of this study are related to the development of continuously operating biosensors based on DNA-modifying enzymes. In this research, we focused on the real-time monitoring of T7 DNA polymerase immobilization. Quartz crystal microbalance (QCM) was applied for the monitoring of immobilization of T7 DNA polymerase and assessment of analytical signals generated during the action of this enzyme.



Figure 2. Scheme of the time-resolved simultaneous measurement of changes in frequency, energy dissipation, and surface saturation by T7 DNA polymerase during the immobilization process on the Quartz Crystal Microbalance sensor.

 
Determination of rSpike Protein by Specific Antibodies with Screen-Printed Carbon Electrode Modified by Electrodeposited Gold Nanostructures

M. Drobysh, V. Liustrovaite, A. Baradoke, R. Viter, C.-F. Chen, A. Ramanavicius, A. Ramanaviciene, Determination of rSpike Protein by Specific Antibodies with Screen-Printed Carbon Electrode Modified by Electrodeposited Gold Nanostructures, Biosensors, 12 (2022) 593. https://doi.org/10.3390/bios12080593
The applicability of electrochemical sensing techniques for detecting specific antibodies against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike proteins in the blood serum of patient samples following coronavirus disease 2019 (COVID-19) was assessed. Herein, screen-printed carbon electrodes (SPCE) with electrodeposited gold nanostructures (AuNS) were modified with L-Cysteine for further covalent immobilization of recombinant SARS-CoV-2 spike proteins (rSpike). The affinity interactions of the rSpike protein with specific antibodies against this protein (anti-rSpike) were assessed using cyclic voltammetry (CV) and differential pulse voltammetry (DPV) methods.

 

Figure 3. Scheme of experimental stages occurring on the SPCE. (1): The formation of SPCE/AuNS by electrodeposition; (2): SPCE/AuNS/SAM formation; (3): the activation of the SPCE/AuNS/SAM by EDC-NHS mixture following SPCE/AuNS/SAM/rSpike formation; (4): ethanolamine blocking of remaining active functional groups and SPCE/AuNS/SAM/rSpike/anti-rSpike immunocomplex formation via the interaction between immobilized rSpike protein and the anti-rSpike antibodies present in the aliquot. 

 
Towards an Electrochemical Immunosensor for the Detection of Antibodies against SARS-CoV-2 Spike Protein

V. Liustrovaite, M. Drobysh, A. Rucinskiene, A. Baradoke, A. Ramanaviciene, I. Plikusiene, U. Samukaite-Bubniene, R. Viter, C.-F. Chen, A. Ramanavicius, Towards an Electrochemical Immunosensor for the Detection of Antibodies against SARS-CoV-2 Spike Protein, Journal of The Electrochemical Society, 169 (2022) 037523. https://doi.org/10.1149/1945-7111/ac5d91
The electrochemical system for the detection of specific antibodies against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) proteins in blood serum patient samples after coronavirus disease 2019 (COVID-19). For this purpose, the recombinant SARS-CoV-2 spike protein (SCoV2-rS) was covalently immobilized on the surface of the gold electrode pre-modified with the mixed self-assembled monolayer (SAMmix) consisting of 11-mercaptoundecanoic acid and 6-mercapto-1-hexanol. The affinity interaction of SCoV2-rS with specific antibodies against this protein (anti-rS) was detected using two electrochemical methods: cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS).



Figure 4. Scheme of experimental stages: (1) SAMmix layer formation on Au electrode (Au/SAMmix); (2) SAMmix activation by EDC-NHS mixture (Au/SAMmix/EDC-NHS); (3) SCoV2-rS immobilisation and formation of Au/SAMmix/SCoV2-rS sensing structure; (4) BSA binding of remaining activated carboxyl groups; (5) affinity interaction of anti-rS with immobilised SCoV2-rS (Au/SAMmix/SCoV2-rS/anti-rS).

 
Molecularly Imprinted Polypyrrole-based Sensor for the Detection of SARS-CoV-2 Spike Glycoprotein

V. Ratautaite, R. Boguzaite, E. Brazys, A. Ramanaviciene, E. Ciplys, M. Juozapaitis, R. Slibinskas, M. Bechelany, A. Ramanavicius, Molecularly Imprinted Polypyrrole based Sensor for the Detection of SARS-CoV-2 Spike Glycoprotein, Electrochimica Acta, 403 (2022) 139581. https://doi.org/10.1016/j.electacta.2021.139581
The application of a polypyrrole-based sensor for the determination of SARS-CoV-2-S spike glycoprotein is described. The electrochemical sensor was designed by molecular imprinting of polypyrrole (Ppy) with SARS-CoV-2-S spike glycoprotein (MIP-Ppy). The electrochemical sensors with MIP-Ppy and with polypyrrole without imprints (NIP-Ppy) layers were electrochemically deposited on a platinum electrode surface by a sequence of potential pulses. The performance of polymer layers was evaluated by pulsed amperometric detection.


Figure 5. Scheme of evaluation by chronoamperometry of Pt electrode modified with non-imprinted polypyrrole (NIP-Ppy) and with molecularly imprinted polypyrrole (MIP-Ppy) with SARS-CoV-2-S glycoprotein imprints. Electrochemical measurements were performed in phosphate-buffered saline (PBS) solution, pH 7.4.

 
Electrochemical sensors based on L-tryptophan molecularly imprinted polypyrrole and polyaniline

V. Ratautaite, E. Brazys, A. Ramanaviciene, A. Ramanavicius, Electrochemical Sensors based on L-Tryptophan Molecularly Imprinted Polypyrrole and Polyaniline, Journal of Electroanalytical Chemistry, 917 (2022) 116389. https://doi.org/10.1016/j.jelechem.2022.116389
The aim of this work was to compare two different conducting polymers (polypyrrole and polyaniline) in the design of the molecularly imprinted polymer (MIP). An l-tryptophan was selected as a template molecule in such MIP-based layers deposited on the graphite electrodes. Further, the MIPs with l-tryptophan imprints were applied in the design of electrochemical sensors for the detection of l-tryptophan. All polymer layers were electrochemically deposited on the electrode surface by the application of potential cycling. The characteristics of all modified electrodes were evaluated by differential pulse voltammetry (DPV) and cyclic voltammetry (CV). The results demonstrate that the molecularly imprinted polypyrrole MIPpy layer has a greater affinity toward l-tryptophan molecules in comparison with other layers evaluated in this study.

Figure 6. Scheme of evaluation of graphite electrode modified with non-imprinted polypyrrole (NIP-Ppy) and with molecularly imprinted polypyrrole (MIP-Ppy) with l-tryptophan imprints. Electrochemical measurements were performed by differential pulse voltammetry in 40 mM BR buffer solution with 0.1 M of KCl, pH 2.5.

 
Evaluation of Electrochromic Properties of Polypyrrole/Poly(Methylene Blue) Layer Doped by Polysaccharides

V. Ratautaite, R. Boguzaite, M.B. Mickeviciute, L. Mikoliunaite, U. Samukaite-Bubniene, A. Ramanavicius, A. Ramanaviciene, Evaluation of Electrochromic Properties of Polypyrrole/Poly(Methylene Blue) Layer Doped by Polysaccharides, Sensors, 22 (2022) 232. https://doi.org/10.3390/s22010232
Polypyrrole (Ppy) and poly(methylene blue) (PMB) heterostructure (Ppy-PMB) was electrochemically formed on the indium tin oxide (ITO) coated glass slides, which served as working electrodes. For electropolymerization, a solution containing pyrrole, methylene blue, and a saccharide (lactose, sucrose, or heparin) that served as a dopant. The aim of this study was to compare the effect of the saccharides (lactose, sucrose, and heparin) on the electrochromic properties of the Ppy-PMB layer. Electrochromic properties were analyzed with respect to the changes in absorbance of the layer at two wavelengths (668 nm and 750 nm) by changing the pH of the surrounding solution and the potential between +0.8 V and −0.8 V.

 
Comparative study of polydopamine and polypyrrole modified yeast cells applied in biofuel cell design

E. Andriukonis, V. Reinikovaite, A. Ramanavicius, Comparative study of polydopamine and polypyrrole modified yeast cells applied in biofuel cell design, Sustainable Energy & Fuels, 6 (2022) 4209-4217. https://doi.org/10.1039/D2SE00634K
Due to high global energy requirements, the research for green-renewable energy has skyrocketed in the past few years. Yeast-based microbial fuel cells (MFC) could serve as a potential alternative energy source.

Redox-active polymers are currently featured as a promising new class of electron mediators with lower cytotoxicity compared to other conventional electron mediators. In this study, we tested two electroconductive polymers, polypyrrole (Ppy) and polydopamine (PDA), which possess good electrical properties and are biocompatible with microorganisms.

Both PDA and Ppy modifications are deemed successful, which is indicated by an increase in the charge transfer from the yeast cells to the electrodes. Overall, our modifications applied shorter incubation times in the polymerization bulk solution and generated a greater electric current of approximately a 5-fold power increase compared to the regular yeast MFCs.



Figure 7. Scheme of the assessment of polydopamine and polypyrrole-modified yeast cells used in the development of biofuel cells.

 
Development of biofuel cells based on anode modified by glucose oxidase, Spirulina platensis-based lysate and multi-walled carbon nanotubes

R. Žalnėravičius, V. Klimas, A. Naujokaitis, A. Jagminas, A. Ramanavičius, Development of biofuel cell based on anode modified by glucose oxidase, Spirulina platensis-based lysate and multi-walled carbon nanotubes, Electrochimica Acta, 426 (2022) 140689. https://doi.org/10.1016/j.electacta.2022.140689
Bioanode was successfully designed using the chemical oxidized multi-walled carbon nanotubes (CNT) and Spirulina platensis-based lysates that facilitate the electron transfer and reduce the open circuit potential (OCP) drop along the electron transfer pathway. Composition, morphology and chemical modification efficiency of CNT was examined using scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX) and simultaneous thermal analysis (STA) coupled with mass spectrometric (MS) analysis of evolving gaseous species (TG/DTA–MS). The results of this study indicate that glucose oxidase (GOx) immobilized on CNT functionalized with S. platensis-based lysates possess superior electron transfer and reduce the OCP drop along the electron transfer pathway.



Figure 8. Scheme of the bioanode consisting of glassy carbon with polyethyleneimine, multi-walled carbon nanotubes (CNT) and Spirulina platensis-based lysates and used for the development of biofuel cells.