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1

Badania wpływu promieniowania elektromagnetycznego na komponenty matryc biosensora

Kłos-Witkowska Aleksandra, Martsenyuk Vasyl

Pomiary Automatyka Robotyka

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2023

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R. 27, nr 4

57--63

PL

W pracy za pomocą zmian przewodności zbadano zmiany konformacyjne proteiny BSA oraz jej kompleksów (BSA-Au oraz BSA-NAA) pod wpływem promieniowania UV oraz MF aplikowanego frakcyjnie w dawkach (3 × 10 min oraz 6 × 10 min) oraz w sposób ciągły (30 min, 60 min). Wykonano analizę porównawczą wpływu promieniowania UV i mikrofalowego w dawkach ciągłych i frakcyjnych na BSA, BSA-Au, BSA-NAA oraz przeanalizowano czułość na pole elektromagnetyczne z zakresu UV i MF dla badanych substancji. Udowodniono efekt przyspieszonych zmian konformacyjnych pod wpływem pola elektromagnetycznego z zakresu UV i MF. Wykazano wpływ czynników na stabilność BSA i jej kompleksów zależny od: rodzaju czynnika, sposobu jego aplikacji oraz czasu ekspozycji. Najbardziej czuły na pole elektromagnetyczne okazał się kompleks BSA-Au.

EN

In this study, the conformational changes of BSA protein and its complexes (BSA-Au and BSA-NAA) under UV and MF radiation applied in fractional doses (3 × 10 min and 6 × 10 min) and continuously (30 min, 60 min) were investigated by means of conductivity changes. A comparative analysis of the effect of UV and microwave radiation in continuous and fractional doses on BSA, BSA-Au, BSA-NAA was performed, and the sensitivity to UV and MF electromagnetic fields of the tested substances was analysed. The effect of accelerated conformational changes under the influence of UV and MF electromagnetic field was proved. The influence of the factors on the stability of BSA and its complexes was shown to depend on: the type of agent, the method of its application and the exposure time. The most sensitive to the electromagnetic field turned out to be the complex BSA-Au.

2

Badanie i analiza czynników determinujących proces tworzenia powłoki bioreceptorowej na powierzchni kontaktów Au w konstrukcji biosensorów wykrywających obecność patogenów w akwakulturze

Prządka Marcin Paweł, Wojcieszak Damian, Pala Katarzyna

Biuletyn Wojskowej Akademii Technicznej

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2023

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Vol. 72, nr 1

47--57

PL

Czujniki zyskują coraz więcej zastosowań, szczególnie w obszarach takich jak opieka zdrowotna, diagnostyka medyczna i weterynaryjna oraz kontrola jakości żywności, której bezpieczeństwo staje się coraz większym problemem na całym świecie. w ramach pracy zbadano czynniki determinujące proces tworzenia powłoki bioreceptorowej na polach kontaktowych biosensorów w postaci warstw au oraz ich odpowiedź impedancyjną do zastosowania w detekcji patogenów w akwakulturze. w wyniku badań z użyciem podłoży biosensorowych o różnej chropowatości zauważono zależność między stopniem rozwinięcia powierzchni elektrod au a formowaniem się prawidłowej warstwy bioreceptorowej. Zmiany te zaobserwowano na podstawie analizy kąta zwilżania dla wybranych podłoży. Przeprowadzone pomiary z użyciem elektrochemicznej spektroskopii impedancyjnej wykazały, że złote elektrody z mniejszą chropowatością podłoża pozwalają uzyskać lepszą odpowiedź impedancyjną.

EN

Sensors are becoming increasingly important every day, especially in applications such as healthcare, medical and veterinary diagnostics, and food quality control, the safety of which is becoming a more important issue worldwide. The present study investigated the critical aspects of the formation of the bioreceptor layer on biosensors and their impedance response for use in pathogen detection in aquaculture. as a result of the studies, conducted with gold substrates of different roughness, a correlation was observed between the degree of development of the au electrode surfaces and formation of the correct bioreceptor layer. These changes were observed on the basis of a wetting angle analysis for selected substrates. Measurements using electrochemical impedance spectroscopy showed that gold electrodes with lower substrate roughness obtained a better impedance response (nyquist plot). On the basis of a comprehensive analysis of the results, an innovative criterion was developed to evaluate the quality of biosensors at an early stage of their production.

3

Bionanomaterials – an emerging field of nanotechnology

Shelin A. R., Meenakshi S.

Archives of Materials Science and Engineering

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2023

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Vol. 121, nr 1

33--41

EN

Purpose: The science that involves nano-sized particles have been shown to have a huge impact on a variety of research fields, such as electronics, medicine, engineering, robotics and technology. The involvement of biological agents in nanoscience helped in the origin of bionanotechnology, which is deeply rooted in therapeutic and medical applications. This review provides an initiative to understand the combination of biological molecules and nanoparticles in delivering a great impression in the world of therapeutics. Design/methodology/approach: Conjugation of nanoparticles with the biological molecules makes them more friendly for the living system by increasing biocompatibility and reducing toxicity. Findings: Growing research in this area has revealed the identification and characterization of numerous biological agents of nano-sized that can serve as better carrier systems. They are exploited in the development of advanced nanoparticle-based targeted drug delivery systems. In general, either the combined form or the one in the derived form of nanoparticles from different biological organisms provides a valuable understanding of their specifications and importance in different therapeutic aspects. Research limitations/implications: The combined form of biological molecules and nanoparticles is not yet well understood, and this might provide a baseline for prospects. Originality/value: This review provides an understanding of biologically synthesized and conjugated nanoparticles and their potential as therapeutic norms and highlights their applications, especially in the clinical field.

4

g-C3N4/ Bio–synthesized silver nanoparticle for fluorometric bio-sensing of acetylcholinesterase and malathion

Ali Abdu Hussen

Advances in Materials Science

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2022

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Vol. 22, nr 3(73)

23--40

EN

Malathion is widely used in agriculture due to their high efficiency as insecticides. They are very toxic hazardous chemicals to both human health and environment even at low concentration. The detection of pesticides (malathion) at the low levels developed by the environmental protection agency (EPA) still remains a challenge. A highly efficient fluorescent biosensor based on g-C3N4/AgNPs for AChE and malathion detection is successfully developed by impregnation method. The structural and morphological properties of the nanocomposites were characterized by using powder X-ray diffraction (XRD), fourier- transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM). The analysis confirmed that there is a strong interfacial interaction between g-C3N4 and AgNPs. The fluorescent responses show an increase in intensity upon the additions of AChE which indicates that AChE as enzyme was hydrolyzing the substrate ACh, with the increase in oxidative electron as the preferred route of reaction. The developed OFF-ON sensor immobilizes by Actylcholestrase (AChE) and use as new probe for malathion detection. In the absence of malathion, AChE−g-C3N4/AgNCs exhibit high fluorescence intensity. However, the strong interaction of the basic sites to malathion, causes fluorescence quenching via static quenching and Ag form aggregation on the surface of g-C3N4. The experimental parameter such as pH of buffer (pH=6), concentration of acetylcholine (1 mM) and malathion (500 μM) were optimized. The sensor was also more sensitive with Stern-Volmer quenching constants (KSV) of 3.48x10 3 M -1. The practical use of this sensor for malathion determination in Khat was also demonstrated. The obtained amount of malathion in Khat is 168.8 μM.

5

Stabilność komponenta sieciującego warstwę receptorową biosensora po dodaniu nanocząstek złota

Kłos-Witkowska Aleksandra, Martsenyuk Vasyl

Pomiary Automatyka Robotyka

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2021

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R. 25, nr 1

49--52

PL

W pracy przeprowadzono badania stabilności składnika warstwy receptorowej biosensora po dodaniu nanocząstek złota. Wykazano przyspieszone zmiany konformacyjne pod wpływem Au. Obliczono względne procentowe zmiany w czasie między czystym białkiem a białkiem domieszkowanym Au. Wykazano, że z czasem zmiany te są większe i przekraczają 20 % w ostatnich dniach eksperymentu.

EN

In this study, the stability of the receptor layer component of a biosensor after addition of gold nanoparticles was investigated. Accelerated conformational changes under the influence of Au were demonstrated. The relative percentage changes over time between the pure protein and the Au doped protein were calculated. It was shown that these changes are greater with time and exceed 20 % in the last days of the experiment.

6

Characterisation of nano-thin film GO/TiO2 layers for Kretschmann-based surface plasmon resonance visible sensing using FDTD method

Khairulazdan N. B., Mohamed R., Berhanuddin D. D., Menon P. S.

Optica Applicata

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2021

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Vol. 51, nr 4

579--587

EN

Kretschmann-based surface plasmon resonance (K-SPR) is suitable for biomolecular sensing which provides label-free and quick detection results with real-time analysis. In this work, we have investigated the effect of graphene oxide (GO) with titanium dioxide (TiO2) thin films that are placed in hybrid above metal layers such as gold (Au), silver (Ag) and copper (Cu) with the presence of chromium (Cr) as an adhesive layer. The thickness of the Au, Ag and Cu metal thin films were optimized to 40, 30 and 30 nm, respectively, with a fixed thickness of GO of 2 nm and TiO2 of 1.9 nm. The sensing was evaluated for SPR excitation at three different visible wavelengths of 633, 670 and 785 nm. The performance of sensing was analyzed based on the reflectance intensity and full-width at half-maximum (FWHM) of the spectrum using the finite-difference time-domain (FDTD) method. The sensitivity was calculated for analyte sensing in dielectric mediums of air versus water. The sensitivity increment percentage (%∆S ) was determined when comparing analyte detection using Cr/metal and Cr/metal/GO/TiO2 sensor structures. The highest sensitivity of 94.51 deg/RIU was achieved for Cr/Cu/GO/TiO2 K-SPR sensor at 633 nm wavelength.

7

Point-of-Care Testing : Biosensor for Norepinephrine Determination

Baluta Sylwia, Swist Agnieszka, Cabaj Joanna, Malecha Karol

International Journal of Electronics and Telecommunications

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2020

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Vol. 66, No. 2

369--372

EN

An useful electrochemical sensing approach was developed for norepinephrine (NE) detection based on semiconducting polymer (9-nonyl-2,7-di(selenophen-2-yl)- 9H-carbazole) and laccase modified platinum electrode (Pt). The miniature Pt biosensor was designed and constructed via the immobilization of laccase in an electroactive layer of the electrode coated with thin polymeric film. This sensing arrangement utilized the catalytic oxidation of NE to norepinephrine quinone. The detection process was based on the oxidation of catecholamine in the presence of enzyme – laccase. With the optimized conditions, the analytical performance demonstrated selectivity in a wide linear range (0.1–200x10-6 M) with a detection limit of 240 nM and a quantification limit of 365 nM. Moreover, the method was successfully applied for selective NE determination in the presence of interfering substances.

8

Badania stabilności w czasie i pod wpływem pola elektromagnetycznego roztworów komponentu sieciującego warstw receptorowych biosensorów

Kłos-Witkowska Aleksandra, Martsenyuk Vasyl, Sverstiuk Andriy

Pomiary Automatyka Robotyka

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2019

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R. 23, nr 4

71--76

PL

W prezentowanej pracy zostały przedstawione wyniki badań stabilności w czasie i pod wpływem czynnika (promieniowanie elektromagnetyczne o długości fali λ = 660 nm) komponentu sieciującego warstw receptorowych biosensorów. Wykazano przyspieszone zmiany konformacyjne (przyspieszoną denaturację) pod wpływem czynnika zewnętrznego. Zauważono, że w badanym czasie (12 dni) największe zmiany stabilności następują między czwartym a ósmym dniem.

EN

The manuscript presents the research on stability over time and under the influence of the factor (electromagnetic radiation with wavelength λ = 660 nm) on crosslinking component of biosensor receptor layers. Accelerated conformational changes (fast denaturization) under the influence of an external factor have been shown. It was noticed that in the examined time (12 days) the biggest changes of stability occur between the 4th and 8th day.

9

Design of a highly sensitive photonic crystal refractive index sensor incorporating ring-shaped GaAs cavity

Rahman-Zadeh F., Danaie M., Kaatuzian H.

Opto-Electronics Review

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2019

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Vol. 27, No. 4

369--377

EN

Two highly sensitive optical sensor topologies are proposed and simulated in this paper. The proposed structures are optimized to provide better performance characteristics such as sensitivity, detection limit, and quality factor. They are based on two-dimensional photonic crystals consisting of rectangular arrays of GaAs rods in SiO2 substrates. Such lattices have bandgaps for transverse magnetic modes. Two-dimensional finite difference time domain and plane wave expansion methods are used for the simulation and analysis of the refractive index sensors and particle swarm optimization method is used to optimize the structural parameters. The designed structures show a high sensitivity to refractive index variations. They are able to detect refractive indices from 1.33 to 1.5. An excellent figure of merit equal to 737 RIU−1 is observed for the proposed structure and a significant improvement is observed compared to the structures reported in the literature.

10

Metody wykrywania alergenów w produktach spożywczych

Pycia Karolina, Kaszuba Joanna, Jaworska Grażyna

Laboratorium - Przegląd Ogólnopolski

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2019

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nr 3

16--23

PL

Podłożem wielu współczesnych chorób cywilizacyjnych, w tym alergii, jest obecny styl życia. Stres, ciągły pośpiech, nieustannie rosnący stopień zanieczyszczenia środowiska naturalnego, znaczny udział w codziennej diecie żywności przetworzonej to tylko niektóre z przyczyn rosnącego tempa zachorowań m.in. na alergie i nietolerancje pokarmowe. Objawy alergii pokarmowych to cały szereg reakcji, począwszy od zmian skórnych, dolegliwości ze strony układu pokarmowego, poprzez trudności w oddychaniu, skończywszy na wstrząsie anafilaktycznym. Dla osób mających zdiagnozowaną alergię pokarmową podstawową metodą „leczenia” jest unikanie żywności zawierającej alergeny. Z kolei po stronie producentów leży obowiązek rzetelnego informowania konsumentów o ich obecności lub braku.

EN

The undertow of many contemporary diseases of affluence, including allergies, is the current lifestyle. Stress, constant rush, constantly increasing level of pollution of the natural environment, significant participation of processed food in the daily diet are just some of the causes of the growing incidence of allergy and food intolerance, among others. The symptoms of food allergies include a whole range of reactions, ranging from skin lesions, gastrointestinal complaints, breathing difficulties to anaphylactic shock. For people who have been diagnosed with food allergy the basic method of „treatment” is to avoid food containing allergens. On the other hand, food producers are obliged to inform consumers about the presence or absence of allergens.

11

Metody oznaczania zawartości białek glutenowych w żywności bezglutenowej

Pycia Karolina, Kaszuba Joanna, Jaworska Grażyna

Laboratorium - Przegląd Ogólnopolski

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2019

|

nr 2

41--46

PL

Celiakia, zwana także chorobą trzewną, polega na trwałej nietolerancji pokarmowej glutenu. Spożycie żywności, w której występują nawet niewielkie ilości glutenu, prowadzi do uszkodzenia błony śluzowej jelita cienkiego, a w efekcie do zaburzenia wchłaniania oraz niedożywienia organizmu. Ważne jest więc zarówno odpowiedzialne postępowanie w zakresie doboru żywności przez osoby zmagające się z tym schorzeniem, jak i podawanie rzetelnej informacji o możliwości zanieczyszczenia produktu glutenem na etykiecie opakowania, co leży w kwestii producentów żywności. Objawy związane z chorobą występują nawet na skutek przyjęcia niewielkiej dawki białek glutenowych. Dlatego też kontrola żywności bezglutenowej (gluten-free) w zakresie obecności tych białek powinna być prowadzona przy użyciu czułych oraz precyzyjnych metod badawczych. Głównym celem artykułu jest charakterystyka metod badawczych służących detekcji białek glutenowych w żywności gluten-free.

EN

Coeliac disease is a persistent gluten intolerance. The consumption of food containing even small amounts of gluten leads to the damage of the mucous membrane of the small intestine and, as a result, to malabsorption and malnutrition. Therefore it is so important that people suffering from the disease select food responsibly, and food manufacturers provide reliable information about the possibility of contaminating a food product with gluten on its packaging. The consumption of even a small dose of gluten proteins causes the symptoms of the disease. Therefore, the control of gluten-free foods for the presence of these proteins should be carried out using sensitive and precise research methods. The main purpose of the article is to characterize research methods used for the detection of gluten proteins in gluten-free foods.

12

Investigation of biosensor potential component stability caused by influence of external condition

Kłos-Witkowska Aleksandra, Martsenyuk Vasyl

Ecological Chemistry and Engineering. S

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2019

|

Vol. 26, nr 4

665--674

EN

The analysis of UV-VIS spectrum was used for testing changes through 36 days and the impact of external conditions (reduced temperature (R), microwave radiation (M) and normal conditions (NC) for comparisons) on the stability of: BSA and BSA-Fe2+ complexes after different treating procedure. The increase of BSA absorption with increasing concentration of Fe2+ was observed. Increased absorption of BSA, and BSA-Fe2+ with time, related probably to conformational changes present in the protein and changes in electrostatic reactions within the BSA-Fe2+ complexes. Examination of the impact of an external factor on stabilization of the protein and complexes showed a tendency to keep the stability under reduced temperature and a trend with accelerated protein and complex aging under microwave radiation. The observed tendencies to changes under the influence of external factors became more significant in time. These effects were most probably related to changes of the protein structure and time, while the observed trend of accelerating the changes was impacted by the applied external factors.

13

Modern noninvasive methods for monitoring glucose levels in patients: a review

Dziergowska Katarzyna, Łabowska Magdalena Beata, Gąsior-Głogowska Marlena, Kmiecik Barbara, Detyna Jerzy

Bio-Algorithms and Med-Systems

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2019

|

Vol. 15, no. 4

art. no. 20190052

EN

This paper presents the current state of the art of noninvasive glucose monitoring. In recent years, we can observe constant increase in the incidence of diabetes. About 40% of all performed blood tests apply to the glucose tests. Formerly, this lifestyle disease occurred mainly in rich countries, but now it is becoming more common in poorer countries. It is related to the increase in life expectancy, unhealthy diet, lack of exercise, and other factors. Untreated diabetes may cause many complications or even death. For this reason, daily control of glucose levels in people with this disorder is very important. Measurements with a traditional glucometer are connected with performing finger punctures several times a day, which is painful and uncomfortable for patients. Therefore, researches on other methods are ongoing. A method that would be fast, noninvasive and cheap could also enable testing the state of the entire population, which is necessary because of the number of people currently living with undiagnosed type 2 diabetes. Although the first glucometer was made in 1966, the first studies on glucose level measurement in tear film were documented as early as 1937. This shows how much a noninvasive method of diabetes control is needed. Since then, there have been more and more studies on alternative methods of glucose measurement, not only from tear fluid, but also from saliva, sweat, or transdermally.

14

Optimization of a dual-slot waveguide for a refractive index biosensor

Sahu S., Ali J., Singh G.

Optica Applicata

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2018

|

Vol. 48, nr 1

161--167

EN

The present article illustrates the modeling and optimization of a dual-slot waveguide for the application of a refractive index biosensor. The nanometer scale waveguide structure uses the silicon-on-insulator platform for the consideration of higher sensitivity and compactness of a resonator biosensor. The modal analysis is performed using the finite difference method based on full vector eigenmode calculation. The maximum field penetration in the lower index region is found for the quasi-TE mode. The sensitivity is maximized through the optimization of the waveguide dimension by relating effective refractive index with the dispersion of a waveguide. The biosensor showed the maximum calculated sensitivity of 461.327 nm/RIU and a limit-of-detection of 2.601 × 10–6 RIU (where RIU denotes refractive index unit).

15

The Effect of Phosphates and Fluorides, Included in TiO2 Nanotube Layers on the Performance of Hydrogen Peroxide Detection

Arkusz K., Krasicka-Cydzik E.

Archives of Metallurgy and Materials

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2018

|

Vol. 63, iss. 2

765--772

EN

Titania nanotube (TNT) arrays fabricated by anodizing of titanium foil in organic (ethylene glycol) and inorganic (phosphoric acid) electrolytes and thermally modified in argon revealed much improved properties to detect hydrogen peroxide. Horseradish peroxidase and acetate thionine co-absorbed by a dip coating on the TNT electrode were used to detect hydrogen peroxide in phosphate buffered saline. The morphology and electrochemical properties of TNT arrays were studied by scanning electron microscopy, electrochemical impedance spectroscopy and cyclic voltammetry. Well defined oxidation and reduction peaks for potassium ferricyanide have been observed for TNT formed in ethylene glycol and annealed in argon. TNT arrays formed in organic electrolyte and annealed in argon indicated more favorable adsorption and electrochemical properties what was confirmed by detection of hydrogen peroxide towards analyte in phosphorate buffered saline solution.

16

Biosensor jako element sieci sensorycznej do pomiaru zmęczenia u górników

Kowal M., Kubal S., Piotrowski P., Staniec K.

Przegląd Telekomunikacyjny + Wiadomości Telekomunikacyjne

|

2017

|

nr 6

544--547, CD

PL

W artykule poruszono problem pomiaru tętna i saturacji krwi u osób będących aktywnymi fizycznie. Zazwyczaj takie pomiary wykonywane są u pacjentów, którzy w trakcie pomiaru pozostają w bezruchu. Nowe zastosowania pomiarów parametrów życiowych, jak choćby określanie na ich podstawie zmęczenia, wymuszają nowe podejście do tematu. Wyjaśniono budowę czujnika oraz sposób pomiaru, jak również przedstawiono wyniki badań weryfikacyjnych w odniesieniu do sprzętu komercyjnego.

EN

The paper addresses the issue of pulse and saturation measurement of physically active persons. Such measurements are usually performed on stationary patients. New applications of physiological parameters measurements, however, such as those intended to determine human fatigue based on them, call for new approach. The sensor construction has been explained along with outcomes of validating investigations performed with commercial tools.

17

Biosensory mikrobiologiczne bazujące na zjawisku luminescencji

Kłos-Witkowska A.

Pomiary Automatyka Robotyka

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2017

|

R. 21, nr 2

79--84

PL

W prezentowanej pracy została przedstawiona charakterystyka biosensorów luminescencyjnych, pokazano ich miejsce w całej rodzinie biosensorów. Opisano rolę mikroorganizmów w biosensorach opartych na luminescencji. Przedstawiono mechanizm luminescencji w bakteriach oraz przykłady genetycznie zmienionych mikroorganizmów i ich zastosowanie jako mikrobiologicznych biosensorów opartych na luminescencji. Zaprezentowano zastosowanie mikrobiologicznych biosensorów luminescencyjnych w ochronie środowiska, przemyśle spożywczym, przemyśle obronnym i medycynie, a także pokazano przykłady komercyjnie dostępnych czujników mikrobiologicznych z uwzględnieniem tych bazujących na zjawisku luminescencji.

EN

In this paper microbiological biosensors based on luminescence were presented, showing their place in the whole family of biosensors. The role of microorganisms in biosensors based on luminescence have been described. The mechanism of luminescence in bacteria and examples of genetically engineered microorganisms, their use as a microbial biosensors based on luminescence has been shown. The use of microbiological luminescent biosensors in: environmental protection, food industry, defense industry and medicine, as well as examples of commercially available microbiological sensors including those based on luminescence phenomenon have been shown. In reviewing the literature, there are numerous work-related microbiological biosensors, but not found among them the manuscript which present selected information on the microbial biosensors based on luminescence phenomenon. Novelty of this study is to provide the selected information on the microbial biosensors based on luminescence and the presentation of their latest applications.

18

Construction of a bilirubin biosensor based on an albumin-immobilized quartz crystal microbalance

Kocakulak M., Bayrak T., Saglam S.

Biocybernetics and Biomedical Engineering

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2017

|

Vol. 37, no. 3

611--617

EN

Bilirubin, a bile pigment, is associated with several diseases and systemic pathologies. The measurement of bilirubin is important for diagnosis and therapy, and many expensive methods are used to measure the bilirubin amount in blood. In this study, a new bilirubin biosensor using quartz crystal microbalances immobilized with albumin is proposed. To measure the effectiveness of the biosensor, a series of experiments was realized with various concentrations of bilirubin, including 1 mg/dL, 2 mg/dL, 5 mg/dL and 10 mg/dL. Comparing blood gas analyzers, laboratory analyzers, skin test devices and nonchemical photometric devices, blood gas analyzers have a range of 0.5–35 mg/dL, laboratory analyzers have a range of 0–30 mg/dL, skin test devices could be used up to 11.7 mg/dL, and nonchemical photometric devices could be evaluated as reliable up to 14.6 mg/dL. The low limit range of the bilirubin detection is between 0.099 mg/dL and 0.146 mg/dL for some special commercial bilirubin measurement devices. Nevertheless, this study presents measurements with a high sensitivity and includes the advantage of reusability by using cheaper materials. To prove albumin immobilization and the bilirubin–albumin interaction atomic force microscopy (AFM) was used, and a good correlation was achieved from AFM images. In conclusion, considering the cost-effectiveness side of the proposed method, a low cost and more sensitive bilirubin measurement device which is effective and reusable was developed instead of the current commercial products.

19

Oligonukleotydy DNA jako warstwy receptorowe sensorów elektrochemicznych

Górski Ł., Ziółkowski R., Bala A., Jarczewska M., Malinowska E.

Wiadomości Chemiczne

|

2015

|

[Z] 69, 5-6

325--336

EN

The need for elaboration of analytical devices of small dimensions and the accessibility of novel nanomaterials caused the increase in the number of publications referring to the development of biosensors. DNA-based biosensors are of special interest and they were primarily used for the determination of a specific sequence which is crucial in the detection of cancer, genetic mutations, pathogens, as well as analysis of modified food. Interestingly, they could be also applied for the detection of other analytes including heavy metal ions, especially in connection with electrochemical techniques. It should be noted that the design of DNA biosensor concerns not only the development of transducer, but also careful preparation of sensing layer and the choice of the method of analytical signal generation. Selectivity is one of the essential parameter of the biosensor that determines its utility, particularly in real samples of complex matrices. In case of DNA sensors dedicated for the detection of complementary sequence, high selectivity is provided by the hybridization process. A pronounced specificity of sensing layer-analyte interaction can be also achieved with the use of functional nucleic acids - aptamers, which change their conformation upon binding an analyte. Herein, DNA-modified electrodes were firstly used for the detection of uranyl ions, as they exhibit high affinity towards phosphate moieties of nuclec acids. It was shown that UO2 2+ interacts with sensing layer independently from the chosen oligonucleotide sequence. Moreover, the influence of Pb2+ was reduced by elimination of adenine, which strongly interacts with lead ions. Another oligonucleotide-based sensor was developed for detection of mercury ions. The results indicate that Hg2+ concentration can be determined only with the use of sequence containing 100% thymine residues. Oligonucleotide-based sensor with receptor layer containing aptamers was elaborated for the detection of Pb2+ ions. In the presence of lead cations, an aptamer probe forms a G-quadruplex structure, a proposed biosensor could be characterized with selectivity towards Pb2+ The performance of DNA-based sensors for UO2 2+, Hg2+ and Pb2+ ions was optimized and addressed the choice of the manner of analytical signal generation, the influence of electrode modification with blocking agent, sensitivity dependence on the oligonucleotide sequence and the possibility of regeneration of sensing layer. Finally, the utility of proposed DNA sensors was tested by analysis in real samples.

20

Biosensory

Kłos-Witkowska A.

Pomiary Automatyka Robotyka

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2015

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R. 19, nr 3

37--40

PL

W prezentowanej pracy została opisana budowa i zasada działania biosensorów. Podano przykłady analitów oraz substancji biologicznych stosowanych w warstwach receptorowych. Przedstawiono zastosowanie biosensorów w medycynie, przemyśle spożywczym, ochronie środowiska, przemyśle obronnym oraz w badaniach biofarmaceutycznych. Opisano trendy i perspektywy rozwoju tego typu urządzeń.

EN

This paper describes design and operation of biosensors. The examples of analytes and biological substances used in bioreceptor layer have been given. Biosensors application in medicine, food, environmental and defence industry as well as in biopharmaceutical research have been presented. Trends and prospects of the development this type of sensors have been shown.