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  • 1
    Online Resource
    Online Resource
    Royal Society of Chemistry (RSC) ; 2022
    In:  RSC Advances Vol. 12, No. 13 ( 2022), p. 7652-7660
    In: RSC Advances, Royal Society of Chemistry (RSC), Vol. 12, No. 13 ( 2022), p. 7652-7660
    Abstract: Monitoring of cells viability is essential in a number of biomedical applications, including cell-based sensors, cell-based microsystems, and cell-based assays. The use of spectroscopic techniques for such purposes is especially advantageous since they are non-invasive, label-free, and non-destructive. However, such an approach must include chemometric analysis of the data to assess the information on cells viability. In the presented article we demonstrate, that excitation–emission matrix (EEM) fluorescence spectroscopy can be applied for reliable determination of cells viability due to the high correlation of EEM fluorescence data with the MTT test data. A375 cells (malignant melanoma) were exposed to UV radiation as a physical stress factor, resulting in a decrease of viability up to ca. 20%, confirmed by the standard MTT test. They were also characterized by means of EEM fluorescence spectroscopy coupled with unfolded partial least squares (UPLS) regression. Statistical evaluation revealed high accordance of the two methods of viability testing in terms of accuracy, precision, and correlation. The presented results are very promising for the development of spectroscopic soft sensors that can be applied for drug screening, biocompatibility testing, tissue engineering, and pharmacodynamic studies.
    Type of Medium: Online Resource
    ISSN: 2046-2069
    Language: English
    Publisher: Royal Society of Chemistry (RSC)
    Publication Date: 2022
    detail.hit.zdb_id: 2623224-8
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  • 2
    Online Resource
    Online Resource
    Elsevier BV ; 2022
    In:  Sensors and Actuators B: Chemical Vol. 351 ( 2022-01), p. 130889-
    In: Sensors and Actuators B: Chemical, Elsevier BV, Vol. 351 ( 2022-01), p. 130889-
    Type of Medium: Online Resource
    ISSN: 0925-4005
    RVK:
    Language: English
    Publisher: Elsevier BV
    Publication Date: 2022
    detail.hit.zdb_id: 1500731-5
    detail.hit.zdb_id: 1021505-0
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  • 3
    In: Analytical Biochemistry, Elsevier BV, Vol. 584 ( 2019-11), p. 113387-
    Type of Medium: Online Resource
    ISSN: 0003-2697
    Language: English
    Publisher: Elsevier BV
    Publication Date: 2019
    detail.hit.zdb_id: 1461105-3
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  • 4
    Online Resource
    Online Resource
    Elsevier BV ; 2022
    In:  Organs-on-a-Chip Vol. 4 ( 2022-12), p. 100014-
    In: Organs-on-a-Chip, Elsevier BV, Vol. 4 ( 2022-12), p. 100014-
    Type of Medium: Online Resource
    ISSN: 2666-1020
    Language: English
    Publisher: Elsevier BV
    Publication Date: 2022
    detail.hit.zdb_id: 3052282-1
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  • 5
    Online Resource
    Online Resource
    The Electrochemical Society ; 2021
    In:  ECS Meeting Abstracts Vol. MA2021-01, No. 60 ( 2021-05-30), p. 1597-1597
    In: ECS Meeting Abstracts, The Electrochemical Society, Vol. MA2021-01, No. 60 ( 2021-05-30), p. 1597-1597
    Abstract: Introduction This presentation will focus on the lab-on-a-chip microsystems for different applications, ranging from cytotoxicity tests to the evaluation of the effectiveness of selected anticancer therapies. When in vitro tests are performed with the use of microsystems, manual activities that are required when seeding cells or administering solutions of tested compounds are eliminated. It allows for greater reproducibility and eliminates some limitations of studies conducted in the macroscale. Moreover, in microsystems it is possible to better reflect in vivo conditions and obtain a homogeneous (same size) population of multicellular spheroids (3D cell model) relatively easily [1]. This way, the results obtained in microfluidic systems can allow to better predict the response of an organism to the tested compounds/nanomaterials or applied anticancer treatment. Microsystems for in vitro studies The first stage in the development of a microsystems for in vitro studies is usually based on a selection of appropriate materials for their fabrication. Because non-toxic materials must be applied for this aim, glass and chosen polymers are among the most often used ones. In addition, the application of transparent materials enables observation of cell cultures during testing. The introduction of cells to microchambers, obtaining specific models of cell culture (monolayer or spheroids culture) as well as nutrient delivery to the cells is achieved thanks to the appropriate geometry of the microchannels and microchambers. In the framework of presented studies, microsystems u obtained by bonding several layers of PDMS or glass and PDMS will be discussed. Methods The cytotoxicity of selected nanomaterials (such as quantum dots or gold nanoparticles) was evaluated with the use of microsystems [2,3]. The research was carried out on two cell culture models (monolayer and spheroids) and the examination of cell viability was based on the fluorescence staining of live and dead cells or Alamar blue test. Additionally, the change in cell morphology during the conducted research was observed. Two types of therapeutic procedures were performed with the use of microsystems. These were photothermal therapy (PTT) [4] and electrochemotherapy (ECT). In the case of PTT, after 24 hours from the introduction of cells, a photoactive agent was introduced into the microsystem (gold nanoparticle solutions were used) and incubated for another 24 hours. After this time, the cell medium was passed through the microsystem to wash away the excess of nanoparticles that did not penetrate or bind to the cell membranes, then a laser irradiation was applied. The ECT procedure was carried out in a microsystem equipped with specially designed electrodes. The electrodes were arranged parallelly to each other and tangent to the culture microcells. After introducing the cytostatic compound into the microsystem, the cells were subjected to electric impulse. In this way, drugs were actively introduced into the cells. Results and Conclusions The conducted experiments allowed to evaluate the cytotoxicity of quantum dots for normal and tumor cell lines. As the tests were carried out for both 2D and 3D models, the obtained results were compared. The effectiveness of the PTT procedure carried out in a microsystem with the use of aptamer-modified nanoparticles was assessed. The procedure was found to be more effective in the case of breast cancer cells than for lung cancer cells. A microsystem for ECT was developed and the effectiveness of this method was compared to chemotherapy, which was also carried out in the microsystem. For drugs that poorly penetrate the membranes by endocytosis, the use of electrical impulses increases the amount of drug introduced into the cells. References [1] Cui P., Wang S., “Application of microfluidic chip technology in pharmaceutical analysis: A review”, Journal of Pharmaceutical Analysis, 2019, 9, 238-247. [2] Grabowska-Jadach I., Haczyk M., Drozd M., Fischer A., Pietrzak M., Malinowska E., Brzózka Z., "Evaluation of biological activity of quantum dots in a microsystem", Electrophoresis, 2016, 35, 165-177. [3] Grabowska-Jadach I., Zuchowska A., Olesik M., Drozd M., Pietrzak M., Malinowska E., Brzózka Z., “Cytotoxicity studies of selected cadmium-based quantum dots on 2D: Vs. 3D cell cultures”, New Journal of Chemistry, 2018, 42, 12787-12795. [4] Kalinowska D., Grabowska-Jadach I., Liwinska M., Drozd M., Pietrzak M., Dybko A., Brzozka Z., “Studies on effectiveness of PTT on 3D tumor model under microfluidic conditions using aptamer-modified nanoshells”, Biosensors and Bioelectronics, 2019, 126, 214-221.
    Type of Medium: Online Resource
    ISSN: 2151-2043
    Language: Unknown
    Publisher: The Electrochemical Society
    Publication Date: 2021
    detail.hit.zdb_id: 2438749-6
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  • 6
    Online Resource
    Online Resource
    The Electrochemical Society ; 2020
    In:  ECS Meeting Abstracts Vol. MA2020-01, No. 27 ( 2020-05-01), p. 1953-1953
    In: ECS Meeting Abstracts, The Electrochemical Society, Vol. MA2020-01, No. 27 ( 2020-05-01), p. 1953-1953
    Abstract: Introduction Lab-on-a-Chip systems are innovative tools which can be used in the field of life sciences. They find applications e.g. in single cell analysis or cytotoxicity tests [1]. Despite the growing popularity of the use of microsystems in biological research, there is a lack of microsystems that may be used in the electrochemotherapy (ECT) studies. ECT is a antitumor therapy, based on an application of electroporation (EP) during standard chemotherapy (CT). EP uses external electric field to form hydrophilic pores in the cells membrane. Electropores are additional migration pathway for molecules which enhanced their delivery into cells [2] . ECT allows to use lower concentration of drug and reduces side effects in comparison to standard chemotherapy [3]. We develop a Lab-on-a-Chip microsystem for cell electroporation that could be used to examine the effectiveness of chemotherapy as well as for evaluation the effectiveness of electrochemotherapy. Microsystem fabrication The microsystem is made of polydimethylsiloxane (PDMS) and glass. Casting method was used to obtained the microchannels and microchambers in PDMS layer. Pairs of gold electrodes were arranged parallelly along the microchannel with microchambers at the distance of 2 mm. The microsystem allows simultaneous culturing of normal and tumor cells. There are four rows of microchambers for each cell line: I - cells not exposed to compound or electric field (control), II - electroporated cells not exposed to compound (control for EP), III – cells electroporated with compound (simulating condition of ECT), IV - cells incubated with compound (simulating condition of CT). In this way, it is possible to evaluate and compare the effectiveness of two types of therapeutic procedures. Method The microchip was sterilized using 70% ethanol and UV radiation. After that, the cell suspension was introduced using a peristaltic pump at a speed of 3.5 µl/min. After 24 h of incubation, the cells medium (control) and the solution of the test compound were respectively introduced into the microsystem, nextly the cells were electroporated. Cell observations were performed using an inverted fluorescence microscope. In addition, fluorescence intensity measurements of the introduced molecules were carried out using a multi-well plate reader. The AlamarBlue test was performed to determine cell viability. For this purpose, a 10% AlamarBlue solution was introduced into the microsystem, than fluorescence intensity was measured at λex=558 nm and λem= 585 nm. Results and Conclusions To determine the optimal electroporation parameters (pulse length, their number, voltage) preliminary experiments were led using propidium iodide (PI). Tests were carried out for two skin cell lines: normal HaCaT and tumor A375. Two sets of parameters were examined: 1 pulse 10 ms and 8 pulses 0.1 ms, each in three voltage variants: 150, 180 and 200V. Cell viability after electroporation was determined. It was found that there were no significant changes in the cell viability after electroporation with the voltage lower than 200V. The efficiency of PI delivery into cells was confirmed by microscopic observation as well as determined by fluorescence intensity measurements. Significantly lower PI level inside cells (at the level of 30%) using 8 pulses 0.1 ms for both cell lines was observed. The best efficiency of PI delivery (about 90%) was observed when 1 pulse of 180V lasting 10 ms was applied. In addition, cell morphology was observed and cells parameters such as: shape factor, sphericity, convexity and elongation were determined. It was confirmed that the electroporation of cells does not change their morphology. Based on the obtained results it was concluded that the optimal electroporation conditions for HaCaT and A375 cell lines are: 1 pulse 10 ms 180V. References [1] Grabowska-Jadach I., Haczyk M., Drozd M., Fischer A., Pietrzak M., Malinowska E., Brzózka Z., "Evaluation of biological activity of quantum dots in a microsystem", Electrophoresis, 2016, 35, 165-177. https://doi.org/10.1002/elps.201500294 [2] Yarmush M. L., Golberg A., Sersa G., Kotnik T., Miklavcic D., “Electroporation-based Technologies for Medicine:Principles, Applications and Challenges”, Annual Review of Biomedical Engineering, 2014, 16, 295-320. https://doi.org/10.1146/annurev-bioeng-071813-104622 [3] Calvet Ch. Y., L. Mir M., "The promising allianceof anti-cancerelectrochemotherapywithimmunotherapy", Cancer Metastasis Review, 2016, 35, 165-177. https://doi.org/10.1007/s10555-016-9615-3 This work was realized with the frame of project Preludium no 2018/31/N/ST4/02922.
    Type of Medium: Online Resource
    ISSN: 2151-2043
    Language: Unknown
    Publisher: The Electrochemical Society
    Publication Date: 2020
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  • 7
    Online Resource
    Online Resource
    The Electrochemical Society ; 2020
    In:  ECS Meeting Abstracts Vol. MA2020-01, No. 32 ( 2020-05-01), p. 2346-2346
    In: ECS Meeting Abstracts, The Electrochemical Society, Vol. MA2020-01, No. 32 ( 2020-05-01), p. 2346-2346
    Abstract: Introduction Nanomaterials due to their physicochemical properties arouse interest of researchers representing various fields of science, including chemical, biological and clinical analysis. Research in these areas has led to a foundation of nanomedicine, in case of which, both diagnosis and therapy of various diseases are based on nanoparticles (e.g. treatment of infectious or cardiovascular diseases and cancer) [1-3]. Nanoparticles made of biodegradable polymers and lipids, gold- and silver-based nanoparticles, carbon nanotubes, semiconductor-based nanoparticles and many others allow the delivery of therapeutic compounds directly to diseased/altered cells. Lab-on-a-chips for cell cultures studies Lab-on-a-chip microsystems are valuable analytical tools that can be used during both in vitro tests of nanomaterials and development of new therapeutic procedures [4]. Lab-on-a-chip systems enable to precisely control the cells’ microenvironment and overcome the limitations of traditional cell culture methods. In microfluidic systems, a transport of necessary substances (oxygen and nutrients) in appropriate concentrations is ensured. In addition, a flow of a culture medium generates shear stresses, the presence of which affects the functioning of cells and can significantly change the diffusion kinetics and interactions of nanomaterials with a cell membrane. By using the microchannel system, it is possible to obtain concentration gradients of the tested compounds, which better mimic conditions found in living organisms. In such systems, the channels and chambers are characterized by a high surface area to volume (SAV) ratio, which reflects the in vivo conditions (gas diffusion, nutrient transport). The consequence of all the mentioned parameters of microsystems is that we can observe phenomena, which do not occur in the macroscale. Method The microsystems that we used during in vitro studies were made of polymer or polymer and glass. The application of biocompatible and transparent materials for microsystems fabrication allows microscopic observation during tests. Microchambers and microchanels in polydimethylsiloxane (PDMS) were obtained using photolithography and molding method. Both elements (PDMS/PDMS or PDMS/glass) of microsystems were permanently bonded after the use of oxygen plasma. Cell culture in the form of a monolayer (2D model) was obtained when a hybrid system was used, while spherical aggregates (3D model) were obtained using a system made of PDMS. Results and Conclusions In our studies, microsystems were used to assess the cytotoxicity of nanomaterials and test the effectiveness of therapeutic procedures. Biological activity of quantum dots was evaluated and their accumulation inside the cells was monitored. It should be underlined, that the application of microsystems made possible to perform and evaluate the effectiveness of two different therapeutic procedures: electrochemotherapy (ECT) and photothermal therapy (PTT). ECT studies were conducted on a cell monolayer (the most commonly used model in biological studies) in a microsystem with integrated electrodes whereas, the PTT studies were conducted on spheroids (model of the early stage of an avascular tumor). References [1] K. Savitsky, X. Yu, Combined strategies for tumor immunotherapy with nanoparticles, Clin Transl Oncol 21 (2019) 1441-1449. doi.org/10.1007/s12094-019-02081-3 [2] J. Xu, W. Han, T. Jia, S. Dong, H. Bi, D. Yang, F. He, Y. Dai, S. Gai, P. Yang, Bioresponsive upconversion nanostructure for combinatorial bioimaging and chemo-photothermal synergistic therapy, Chemical Engineering Journal 342 (2018) 446-457. doi.org/10.1016/j.cej.2018.02.109 [3] C.K.W. Chan, L. Zhang, C.K Cheng, H. Yang, Y. Huang, X.Y. Tian, C.H.J. Choi, Recent Advances in Managing Atherosclerosis via Nanomedicine, Small 14 (2018) 1702793. doi: 0.1002/smll.201702793 [4] D. Kalinowska, I. Grabowska-Jadach, M. Liwińska, M. Drozd, M. Pietrzak, A. Dybko, Z. Brzózka, Studies on effectiveness of PTT on 3D tumor model under microfluidic conditions using aptamer-modified nanoshells, Biosens Bioelectron 126 (2018) 214-221. doi.org/10.1016/j.bios.2018.10.069
    Type of Medium: Online Resource
    ISSN: 2151-2043
    Language: Unknown
    Publisher: The Electrochemical Society
    Publication Date: 2020
    detail.hit.zdb_id: 2438749-6
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  • 8
    Online Resource
    Online Resource
    Elsevier BV ; 2019
    In:  Bioelectrochemistry Vol. 126 ( 2019-04), p. 86-91
    In: Bioelectrochemistry, Elsevier BV, Vol. 126 ( 2019-04), p. 86-91
    Type of Medium: Online Resource
    ISSN: 1567-5394
    Language: English
    Publisher: Elsevier BV
    Publication Date: 2019
    detail.hit.zdb_id: 1496503-3
    SSG: 12
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  • 9
    Online Resource
    Online Resource
    IOP Publishing ; 2021
    In:  Nanotechnology Vol. 32, No. 5 ( 2021-01-29), p. 055704-
    In: Nanotechnology, IOP Publishing, Vol. 32, No. 5 ( 2021-01-29), p. 055704-
    Abstract: Reactive oxygen species (ROS) play an important role in various physiological processes of living organisms. However, their increased concentration is usually considered as a threat for our health. Plants, invertebrates, and vertebrates including humans have various enzymatic and non-enzymatic defence systems against ROS. Unfortunately, both bad condition of surrounding environment and unhealthy lifestyle can interfere with an activity of enzymes responsible for a regulation of ROS levels. Therefore, it is important to look for alternative ROS scavengers, which could be administrated to chosen tissues to prevent pathological processes such as distortion of DNA or RNA structures and oxidation of proteins and lipids. One of the most recently proposed solutions is the application of nanozymes, which could mimic the activity of essential enzymes and prevent excessive activity of ROS. In this work, nanoparticles of Au, Pt, Pd, Ru and Rh were synthesized and studied in this regard. Peroxidase-, catalase (CAT)- and superoxide dismutase (SOD)-like activity of obtained nanoparticles were tested and compared using different methods. The influence of bovine and human albumins on CAT- and peroxidase-like activity was examined. Moreover, in the case of CAT-like activity, an influence of pH and temperature was examined and compared. Determination of SOD-like activity using the methods described for the examination of the activity of native enzyme was not fully successful. Moreover, cytotoxicity of chosen nanoparticles was studied on both regular and tumor cells.
    Type of Medium: Online Resource
    ISSN: 0957-4484 , 1361-6528
    Language: Unknown
    Publisher: IOP Publishing
    Publication Date: 2021
    detail.hit.zdb_id: 1362365-5
    SSG: 11
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  • 10
    Online Resource
    Online Resource
    Wiley ; 1989
    In:  American Journal of Botany Vol. 76, No. 12 ( 1989-12), p. 1759-1768
    In: American Journal of Botany, Wiley, Vol. 76, No. 12 ( 1989-12), p. 1759-1768
    Abstract: Light microscopic observations were made on 22 ovules from fertile plants and 108 ovules from sterile plants of the cv. KS synaptic mutant, a highly male‐sterile, female‐sterile line of soybean [ Glycine max (L.) Merr.] (2 n = 2 x = 40). Ovules of fertile siblings contained normal embryo sacs and embryos. Ovules from sterile plants contained various irregularities. The most consistent abnormality was the failure of the embryo sac to attain normal size. Small megasporocytes of irregular shape were seen; only one megasporocyte of normal shape and size was noted. No linear tetrads were found. However, two ovules contained nonlinear triads. A range from zero to 28 cells and nuclei, of various sizes, were identifiable in small megagametophytes and embryo sacs. Degeneration of these nuclei and cells was noted as early as the four‐nucleate gametophyte stage. Other ovules contained degenerated nucellar centers without embryo sacs. Two ovules appeared to be normal. Late postpollination stages were marked by shrunken nucellus and integuments. The presence of pollen tube traces, endosperm, and aborting embryos in ovules of hand‐pollinated flowers from sterile plants suggested that no incompatibility was involved. Degeneration of the gametophyte and embryo sac contents at many developmental stages indicated a wide array of effects, possibly resulting from meiotic irregularities similar to those seen in microsporogenesis of this mutant.
    Type of Medium: Online Resource
    ISSN: 0002-9122 , 1537-2197
    URL: Issue
    RVK:
    Language: English
    Publisher: Wiley
    Publication Date: 1989
    detail.hit.zdb_id: 2053581-8
    SSG: 12
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