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Glibitskiy D, Gorobchenko O, Nikolov O, Cheipesh T, Dzhimieva T, Zaitseva I, Roshal A, Semenov M, Glibitskiy G. Influence of aluminum and iron chlorides on the parameters of zigzag patterns on films dried from BSA solutions. Sci Rep 2023; 13:9426. [PMID: 37296212 DOI: 10.1038/s41598-023-36515-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2023] [Accepted: 06/05/2023] [Indexed: 06/12/2023] Open
Abstract
The relationships between the structural and aggregational state of bovine serum albumin (BSA) and the specific length and total number of zigzag pattern segments of the film textures formed upon drying biopolymer solutions with aluminum and iron chlorides have been shown. To obtain films, saline solutions of BSA were dried in a glass cuvette under thermostatically controlled conditions. It is shown that the formation of zigzag structures is sensitive to the influence of aluminum chlorides Al3+ and iron chlorides Fe3+ and depend on the concentration of AlCl3 and FeCl3. This may be due to a change in the charge and size of BSA particles and due to a change in conformation or a violation of the structure of BSA. These factors, in turn, affect the hydration of the solution components and the structural state of free water in solution, which presumably also affects the formation of zigzag structures. It is established that the analysis of the specific length and the number of segments of zigzag patterns makes it possible to evaluate changes in the state of biopolymers in the initial solution during structural changes and aggregation.
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Affiliation(s)
- Dmitriy Glibitskiy
- O. Ya. Usikov Institute for Radiophysics and Electronics, National Academy of Sciences of Ukraine, 12 Academician Proskura Str., Kharkiv, 61085, Ukraine.
| | - Olga Gorobchenko
- V. N. Karazin Kharkiv National University, 4 Svobody Sq., Kharkiv, 61022, Ukraine
| | - Oleg Nikolov
- V. N. Karazin Kharkiv National University, 4 Svobody Sq., Kharkiv, 61022, Ukraine
| | - Tatyana Cheipesh
- V. N. Karazin Kharkiv National University, 4 Svobody Sq., Kharkiv, 61022, Ukraine
| | - Tatyana Dzhimieva
- V. N. Karazin Kharkiv National University, 4 Svobody Sq., Kharkiv, 61022, Ukraine
| | - Inna Zaitseva
- V. N. Karazin Kharkiv National University, 4 Svobody Sq., Kharkiv, 61022, Ukraine
- O. M. Beketov National University of Urban Economy in Kharkiv, 17 Marshal Bazhanov Str., Kharkiv, 61002, Ukraine
| | - Alexander Roshal
- Institute for Chemistry, V. N. Karazin Kharkiv National University, 4 Svobody Sq., Kharkiv, 61022, Ukraine
| | - Mihail Semenov
- O. Ya. Usikov Institute for Radiophysics and Electronics, National Academy of Sciences of Ukraine, 12 Academician Proskura Str., Kharkiv, 61085, Ukraine
| | - Gennadiy Glibitskiy
- O. Ya. Usikov Institute for Radiophysics and Electronics, National Academy of Sciences of Ukraine, 12 Academician Proskura Str., Kharkiv, 61085, Ukraine
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Efstratiou M, Christy JRE, Bonn D, Sefiane K. Transition from Dendritic to Cell-like Crystalline Structures in Drying Droplets of Fetal Bovine Serum under the Influence of Temperature. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2022; 38:4321-4331. [PMID: 35357835 PMCID: PMC9009182 DOI: 10.1021/acs.langmuir.2c00019] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/04/2022] [Revised: 03/11/2022] [Indexed: 06/14/2023]
Abstract
The desiccation of biofluid droplets leads to the formation of complex deposits which are morphologically affected by the environmental conditions, such as temperature. In this work, we examine the effect of substrate temperatures between 20 and 40 °C on the desiccation deposits of fetal bovine serum (FBS) droplets. The final dried deposits consist of different zones: a peripheral protein ring, a zone of protein structures, a protein gel, and a central crystalline zone. We focus on the crystalline zone showing that its morphological and topographical characteristics vary with substrate temperature. The area of the crystalline zone is found to shrink with increasing substrate temperature. Additionally, the morphology of the crystalline structures changes from dendritic at 20 °C to cell-like for substrate temperatures between 25 and 40 °C. Calculation of the thermal and solutal Bénard-Marangoni numbers shows that while thermal effects are negligible when drying takes place at 20 °C, for higher substrate temperatures (25-40 °C), both thermal and solutal convective effects manifest within the drying drops. Thermal effects dominate earlier in the evaporation process leading, we believe, to the development of instabilities and, in turn, to the formation of convective cells in the drying drops. Solutal effects, on the other hand, are dominant toward the end of drying, maintaining circulation within the cells and leading to crystallization of salts in the formed cells. The cell-like structures are considered to form because of the interplay between thermal and solutal convection during drying. Dendritic growth is associated with a thicker fluid layer in the crystalline zone compared to cell-like growth with thinner layers. For cell-like structures, we show that the number of cells increases and the area occupied by each cell decreases with temperature. The average distance between cells decreases linearly with substrate temperature.
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Affiliation(s)
- Marina Efstratiou
- Division
of Pharmacy and Optometry, Faculty of Biology, Medicine and Health, The University of Manchester, Stopford Building, Oxford Road, Manchester M13 9PL, U.K.
- Institute
of Multiscale Thermofluids, School of Engineering, The University of Edinburgh, King’s Buildings, James Clerk Maxwell Building, Peter Guthrie
Tait Road, King’s Buildings, Edinburgh EH9 3FD, U.K.
| | - John R. E. Christy
- Institute
of Multiscale Thermofluids, School of Engineering, The University of Edinburgh, King’s Buildings, James Clerk Maxwell Building, Peter Guthrie
Tait Road, King’s Buildings, Edinburgh EH9 3FD, U.K.
| | - Daniel Bonn
- Institute
of Physics, University of Amsterdam, Science Park 904, 1098XH Amsterdam, The Netherlands
| | - Khellil Sefiane
- Institute
of Multiscale Thermofluids, School of Engineering, The University of Edinburgh, King’s Buildings, James Clerk Maxwell Building, Peter Guthrie
Tait Road, King’s Buildings, Edinburgh EH9 3FD, U.K.
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3
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The Effect of Substrate Temperature on the Evaporative Behaviour and Desiccation Patterns of Foetal Bovine Serum Drops. COLLOIDS AND INTERFACES 2021. [DOI: 10.3390/colloids5040043] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The drying of bio-fluid drops results in the formation of complex patterns, which are morphologically and topographically affected by environmental conditions including temperature. We examine the effect of substrate temperatures between 20 °C and 40 °C, on the evaporative dynamics and dried deposits of foetal bovine serum (FBS) drops. The deposits consist of four zones: a peripheral protein ring, a zone of protein structures, a protein gel, and a central crystalline zone. We investigate the link between the evaporative behaviour, final deposit volume, and cracking. Drops dried at higher substrate temperatures in the range of 20 °C to 35 °C produce deposits of lower final volume. We attribute this to a lower water content and a more brittle gel in the deposits formed at higher temperatures. However, the average deposit volume is higher for drops dried at 40 °C compared to drops dried at 35 °C, indicating protein denaturation. Focusing on the protein ring, we show that the ring volume decreases with increasing temperature from 20 °C to 35 °C, whereas the number of cracks increases due to faster water evaporation. Interestingly, for deposits of drops dried at 40 °C, the ring volume increases, but the number of cracks also increases, suggesting an interplay between water evaporation and increasing strain in the deposits due to protein denaturation.
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Pal A, Gope A, Iannacchione G. Temperature and Concentration Dependence of Human Whole Blood and Protein Drying Droplets. Biomolecules 2021; 11:231. [PMID: 33562850 PMCID: PMC7915023 DOI: 10.3390/biom11020231] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2020] [Revised: 01/24/2021] [Accepted: 02/01/2021] [Indexed: 12/31/2022] Open
Abstract
The drying of bio-colloidal droplets can be used in many medical and forensic applications. The whole human blood is the most complex bio-colloid system, whereas bovine serum albumin (BSA) is the simplest. This paper focuses on the drying characteristics and the final morphology of these two bio-colloids. The experiments were conducted by varying their initial concentrations, and the solutions were dried under various controlled substrate temperatures using optical and scanning electron microscopy. The droplet parameters (the contact angle, the fluid front, and the first-order image statistics) reveal the drying process's unique features. Interestingly, both BSA and blood drying droplets' contact angle measurements show evidence of a concentration-driven transition as the behavior changes from non-monotonic to monotonic decrease. This result indicates that this transition behavior is not limited to multi-component bio-colloid (blood) only, but may be a phenomenon of a bio-colloidal solution containing a large number of interacting components. The high dilution of blood behaves like the BSA solution. The ring-like deposition, the crack morphology, and the microstructures suggest that the components have enough time to segregate and deposit onto the substrate under ambient conditions. However, there is insufficient time for evaporative-driven segregation to occur at elevated temperatures, as expected.
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Affiliation(s)
- Anusuya Pal
- Order-Disorder Phenomena Laboratory, Department of Physics, Worcester Polytechnic Institute, Worcester, MA 01609, USA;
| | - Amalesh Gope
- Department of English, Tezpur University, Tezpur 784028, Assam, India;
| | - Germano Iannacchione
- Order-Disorder Phenomena Laboratory, Department of Physics, Worcester Polytechnic Institute, Worcester, MA 01609, USA;
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Pathak B, Christy J, Sefiane K, Gozuacik D. Complex Pattern Formation in Solutions of Protein and Mixed Salts Using Dehydrating Sessile Droplets. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2020; 36:9728-9737. [PMID: 32787115 DOI: 10.1021/acs.langmuir.0c01122] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
A sessile droplet of a complex fluid exhibits several stages of drying leading to the formation of a final pattern on the substrate. We report such pattern formation in dehydrating droplets of protein (BSA) and salts (MgCl2 and KCl) at various concentrations of the two components (protein and salts) as part of a parametric study for the understanding of complex patterns of dehydrating biofluid droplets (blood and urine), which will eventually be used for diagnosis of bladder cancer. The exact analysis of the biofluid patterns will require a rigorous parametric study; however, the current work provides an initial understanding of the effect of the basic components present in a biofluid droplet. Arrangement of the protein and the salts, due to evaporation, leads to the formation of some very distinctive final structures at the end of the droplet lifetime. Furthermore, these structures can be manipulated by varying the initial ratio of the two components in the solution. MgCl2 forms chains of crystals beyond a threshold initial concentration of protein (>3 wt %). However, the formation of such a crystal is also limited by the maximum concentration of the salt initially present in the droplet (≤1 wt %). On the other hand, KCl forms dendritic and rectangular crystals in the presence of BSA. The formation of these crystals also depends on the relative concentration of salt and protein in the droplet. We also investigated the dried-out patterns in dehydrating droplets of mixed salts (MgCl2 + KCl) and protein. The patterns can be tuned from a continuous dendritic structure to a snow-flake type structure just by altering the initial ratio of the two salts in the mixture, keeping all other parameters constant.
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Affiliation(s)
- Binita Pathak
- Department of Mechanical Engineering, Indian Institute of Technology, BHU, Varanasi 221005, India
| | - John Christy
- School of Engineering, The University of Edinburgh, Kings Buildings, Edinburgh EH9 3JL, United Kingdom
| | - Khellil Sefiane
- School of Engineering, The University of Edinburgh, Kings Buildings, Edinburgh EH9 3JL, United Kingdom
- Tianjin Key Lab of Refrigeration Technology, Tianjin University of Commerce, Tianjin City 300134, PR China
| | - Devrim Gozuacik
- Koç University, School of Medicine, KUTTAM Research Center for Translational Medicine, Topkapı-Zeytinburnu, 34010 Istanbul, Turkey
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Basu N, Mukherjee R. Morphology modulation in evaporative drying mediated crystallization of sodium chloride solution droplet with surfactant. SOFT MATTER 2018; 14:7883-7893. [PMID: 30229795 DOI: 10.1039/c8sm01370e] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
We report the evaporative drying of an aqueous droplet containing a dilute solution of sodium chloride (NaCl) on a hydrophobic substrate made of cross-linked poly-dimethyl siloxane (PDMS). The salt concentration Cn was varied between 0.08 molar (M) and 2.0 M. The contact line of the evaporating droplets shows significant initial retraction for all Cn, before they get pinned. While the final morphology comprises a few small NaCl crystals deposited around the pinned contact line, in droplets with a low Cn (<0.5 M), it transforms to a single large salt crystal when Cn > 0.7 M with no peripheral deposition. We further show that the deposition morphology drastically changes when an anionic surfactant, sodium dodecyl sulfate (SDS), is added into the salt-solutions. Even in the surfactant-laden droplets, the final deposition morphology changes significantly as a function of Cn. It transforms from a thick SDS ring surrounding a fractal-like deposit of NaCl crystallites at lower Cn to a peripheral deposit of NaCl crystals at higher Cn due to competition between micelle formation and crystallization. However, the crystallographic orientation of the deposited NaCl crystals remains unaltered irrespective of the presence of surfactant.
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Affiliation(s)
- Nandita Basu
- Instability and Soft Patterning Laboratory, Department of Chemical Engineering, Indian Institute of Technology Kharagpur, Pin 721 302, West Bengal, India.
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7
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Chen R, Zhang L, Zang D, Shen W. Blood drop patterns: Formation and applications. Adv Colloid Interface Sci 2016; 231:1-14. [PMID: 26988066 DOI: 10.1016/j.cis.2016.01.008] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2015] [Revised: 01/01/2016] [Accepted: 01/27/2016] [Indexed: 01/25/2023]
Abstract
The drying of a drop of blood or plasma on a solid substrate leads to the formation of interesting and complex patterns. Inter- and intra-cellular and macromolecular interactions in the drying plasma or blood drop are responsible for the final morphologies of the dried patterns. Changes in these cellular and macromolecular components in blood caused by diseases have been suspected to cause changes in the dried drop patterns of plasma and whole blood, which could be used as simple diagnostic tools to identify the health of humans and livestock. However, complex physicochemical driving forces involved in the pattern formation are not fully understood. This review focuses on the scientific development in microscopic observations and pattern interpretation of dried plasma and whole blood samples, as well as the diagnostic applications of pattern analysis. Dried drop patterns of plasma consist of intricate visible cracks in the outer region and fine structures in the central region, which are mainly influenced by the presence and concentration of inorganic salts and proteins during drying. The shrinkage of macromolecular gel and its adhesion to the substrate surface have been thought to be responsible for the formation of the cracks. Dried drop patterns of whole blood have three characteristic zones; their formation as functions of drying time has been reported in the literature. Some research works have applied engineering treatment to the evaporation process of whole blood samples. The sensitivities of the resultant patterns to the relative humidity of the environment, the wettability of the substrates, and the size of the drop have been reported. These research works shed light on the mechanisms of spreading, evaporation, gelation, and crack formation of the blood drops on solid substrates, as well as on the potential applications of dried drop patterns of plasma and whole blood in diagnosis.
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Affiliation(s)
- Ruoyang Chen
- Department of Chemical Engineering, Monash University, Wellington Road, Clayton Campus, Victoria 3800, Australia
| | - Liyuan Zhang
- Department of Chemical Engineering, Monash University, Wellington Road, Clayton Campus, Victoria 3800, Australia
| | - Duyang Zang
- Functional Soft Matter and Materials Group (FS2M), Key Laboratory of Space Applied Physics and Chemistry of Ministry of Education, School of Science, Northwestern Polytechnical University, Shaanxi 710129, China
| | - Wei Shen
- Department of Chemical Engineering, Monash University, Wellington Road, Clayton Campus, Victoria 3800, Australia.
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Glibitskiy G, Glibitskiy D, Gorobchenko O, Nikolov O, Roshal A, Semenov M, Gasan A. Textures on the surface of BSA films with different concentrations of sodium halides and water state in solution. NANOSCALE RESEARCH LETTERS 2015; 10:155. [PMID: 25897305 PMCID: PMC4395624 DOI: 10.1186/s11671-015-0860-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/31/2014] [Accepted: 03/11/2015] [Indexed: 06/04/2023]
Abstract
The formation of the textures on the surface of the films from the solutions of bovine serum albumin (BSA) with sodium halides (NaF, NaCl, and NaBr) of various concentrations was studied. The formation of symmetric zigzag textures on the surface of BSA films (Cryst Eng 3:173-194, 2000) in the presence of sodium halides depends on the conformational state of the protein globule. Thermal denaturation of BSA also did not allow to form zigzag textures on the surface of the films.
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Affiliation(s)
- Gennadiy Glibitskiy
- />A.Ya. Usikov Institute for Radiophysics and Electronics, National Academy of Sciences of Ukraine, 12, Academician Proskura Str, Kharkiv, 61085 Ukraine
| | - Dmitriy Glibitskiy
- />A.Ya. Usikov Institute for Radiophysics and Electronics, National Academy of Sciences of Ukraine, 12, Academician Proskura Str, Kharkiv, 61085 Ukraine
| | - Olga Gorobchenko
- />Department of Molecular and Medical Biophysics, School of Radiophysics, V.N. Karazin Kharkiv National University, 4 Svobody Sq, Kharkiv, 61022 Ukraine
| | - Oleg Nikolov
- />Department of Molecular and Medical Biophysics, School of Radiophysics, V.N. Karazin Kharkiv National University, 4 Svobody Sq, Kharkiv, 61022 Ukraine
| | - Alexander Roshal
- />Institute for Chemistry, V.N. Karazin Kharkiv National University, 4 Svobody Sq, Kharkiv, 61022 Ukraine
| | - Mikhail Semenov
- />A.Ya. Usikov Institute for Radiophysics and Electronics, National Academy of Sciences of Ukraine, 12, Academician Proskura Str, Kharkiv, 61085 Ukraine
| | - Anatoliy Gasan
- />A.Ya. Usikov Institute for Radiophysics and Electronics, National Academy of Sciences of Ukraine, 12, Academician Proskura Str, Kharkiv, 61085 Ukraine
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Dutta T, Giri A, Choudhury MD, Tarafdar S. Experiment and simulation of multifractal growth of crystalline NaCl aggregates in aqueous gelatin medium. Colloids Surf A Physicochem Eng Asp 2013. [DOI: 10.1016/j.colsurfa.2013.04.040] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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10
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Tarasevich Y, Vodolazskaya I, Bondarenko O. Modeling of spatial–temporal distribution of the components in the drying sessile droplet of biological fluid. Colloids Surf A Physicochem Eng Asp 2013. [DOI: 10.1016/j.colsurfa.2013.04.069] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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11
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Pattern formation in droplets of starch gels containing NaCl dried on different surfaces. Colloids Surf A Physicochem Eng Asp 2013. [DOI: 10.1016/j.colsurfa.2013.04.064] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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12
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Gorr HM, Zueger JM, McAdams DR, Barnard JA. Salt-induced pattern formation in evaporating droplets of lysozyme solutions. Colloids Surf B Biointerfaces 2012. [PMID: 23201720 DOI: 10.1016/j.colsurfb.2012.09.043] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Solute self-organization during evaporation of colloidal sessile droplets has attracted the attention of researchers over the past few decades due to a variety of technological applications. Recently, pattern formation during evaporation of various biofluids has been studied due to potential applications in screening and diagnosis. The complex morphological patterns in the deposit are unique to various disorders and are influenced by various physical mechanisms occurring during evaporation. These complex patterns can be better understood by studying evaporation of model solutions of biological relevance. Here, we examine the general features of pattern formation during sessile droplet evaporation of aqueous lysozyme solutions with varying concentrations of NaCl. Lysozyme is a globular protein found in biological fluids such as tears and saliva. The morphological evolution of the droplet is studied by time-lapse video during evaporation via reflection optical microscopy. The final deposits exhibit an amorphous peripheral ring and interior regions containing crystallites and dendritic forms, dependent on NaCl concentration. Scanning electron microscopy (SEM) images demonstrate the multi-scale hierarchical nature of these structures.
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Affiliation(s)
- Heather Meloy Gorr
- Department of Mechanical Engineering and Materials Science, University of Pittsburgh, Pittsburgh, PA, USA.
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Abstract
This review treats the biological properties of the various anionic calix[n]arenes, both as soluble forms and in the colloidal state. The complexation of these molecules with amino-acids, peptides and proteins is discussed, as is their interaction with model membranes. The complexations with various Active Pharmaceutical Ingredients as complexes, for tamoxifen as solid state and colloidal structures, are treated in depth. Two sections deal with the direct biological action of the calix[n]arenes and their use as biosensors. A final section deals with the toxicity, in reality the lack of toxicity of the calix[n]arenes.
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Affiliation(s)
- Florent Perret
- ICBMS, UMR 5246, Univ Lyon 1, Villeurbanne, F69622, France.
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Tay L, Rowell NL, Poitras D, Fraser JW, Lockwood DJ, Boukherroub R. Bovine serum albumin adsorption on passivated porous silicon layers. CAN J CHEM 2004. [DOI: 10.1139/v04-129] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Hydrogen-terminated porous silicon (pSi-H) films were fabricated through electrochemical anodization of crystalline silicon in hydrofluoric-acid-based solutions. The pSi-H surface was chemically functionalized by thermal reaction with undecylenic acid to produce an organic monolayer covalently attached to the silicon surface through SiC bonds and bearing an acid terminal group. Bovine serum albumin (BSA) was adsorbed onto such surface-modified pSi structures. The resulting surfaces were characterized using scanning electron microscopy (SEM), reflection FT-IR spectroscopy, and ellipsometry. SEM showed that the porous films were damaged and partially lifted off the silicon substrate after a prolonged BSA adsorption. Ellipsometry analysis revealed that the BSA penetrated ∼1.3 µm into the porous structure. The film damage is likely a result of BSA anchoring itself tightly through strong electrostatic interaction with the acid-covered Si sidewalls. A change in surface tension during BSA film formation then causes the pSi layer to buckle and lift off the underlying Si substrate. FT-IR results from the undecylenic-acid-modified pSi surfaces before and after BSA adsorption showed the presence of strong characteristic amide I, II, and III vibrational bands after BSA adsorption. The surface properties of the pSi matrix and its interactions with BSA are examined in this study.Key words: ellipsometry, porous silicon, protein adsorption, surface passivation.
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15
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Tarasevich YY. Mechanisms and models of the dehydration self-organization in biological fluids. ACTA ACUST UNITED AC 2004. [DOI: 10.3367/ufnr.0174.200407f.0779] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022]
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Lazar AN, Shahgaldian P, Coleman AW. Anion recognition effects in the structuring of bovine serum albumin films. ACTA ACUST UNITED AC 2001. [DOI: 10.1016/s1472-7862(02)00017-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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