1
|
Nguyen MD, Nguyen KN, Malo S, Banerjee I, Wu D, Du-Thumm L, Dauphin-Ducharme P. Electrochemical Aptamer-Based Biosensors for Measurements in Undiluted Human Saliva. ACS Sens 2023; 8:4625-4635. [PMID: 37992319 DOI: 10.1021/acssensors.3c01624] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2023]
Abstract
Although blood remains a gold standard diagnostic fluid for most health exams, it involves an unpleasant and relatively invasive sampling procedure (finger pricking or venous draw). Saliva contains many relevant and useful biomarkers for diagnostic purposes, and its collection, in contrast, is noninvasive and can be obtained with minimal effort. Current saliva analyses are, however, achieved using chromatography or lateral flow assays, which, despite their high accuracy and sensitivity, can demand expensive laboratory-based instruments operated by trained personnel or offer only semiquantitative results. In response, we investigated electrochemical aptamer-based (E-AB) biosensors, a reagentless sensing platform, to allow for continuous and real-time measurements directly in undiluted, unstimulated human whole saliva. As a proof-of-concept study, we developed E-AB biosensors capable of detecting low-molecular-weight analytes (glucose and adenosine monophosphate (AMP)). To our knowledge, we report the first E-AB sensor for glucose, an approach that is inherently independent of its chemical reactivity in contrast to home glucometers. For these three sensors, we evaluated their figures of merits, stability, and reusability over short- and long-term exposure directly in saliva. In doing so, we found that E-AB sensors allow rapid and convenient molecular measurements in whole saliva with unprecedented sensitivities in the pico- to nanomolar regime and could be regenerated and reused up to 7 days when washed and stored in phosphate-buffered saline at room temperature. We envision that salivary molecular measurements using E-AB sensors are a promising alternative to invasive techniques and can be used for improved point-of-care clinical diagnosis and at-home measurements.
Collapse
Affiliation(s)
- Minh-Dat Nguyen
- Département de chimie, Université de Sherbrooke, Sherbrooke, Québec J1K 2R1, Canada
| | - Khoa-Nam Nguyen
- Département de chimie, Université de Sherbrooke, Sherbrooke, Québec J1K 2R1, Canada
| | - Samuel Malo
- Département de chimie, Université de Sherbrooke, Sherbrooke, Québec J1K 2R1, Canada
| | - Indrani Banerjee
- Colgate, Research and Development Center, Piscataway, New Jersey 08854, United States
| | - Donghui Wu
- Colgate, Research and Development Center, Piscataway, New Jersey 08854, United States
| | - Laurence Du-Thumm
- Colgate, Research and Development Center, Piscataway, New Jersey 08854, United States
| | | |
Collapse
|
2
|
Weston A, Vladescu SC, Reddyhoff T, Griffiths A, Crouzier T, Fielden M, Garnett JA, Carpenter GH. The influence of ions on the lubricative abilities of mucin and the role of sialic acids. Colloids Surf B Biointerfaces 2023; 227:113327. [PMID: 37172419 DOI: 10.1016/j.colsurfb.2023.113327] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Revised: 04/17/2023] [Accepted: 04/25/2023] [Indexed: 05/15/2023]
Abstract
Mucus reduces friction between epithelial surfaces by providing lubrication in the boundary and mixed regime. Mucins, the main macromolecule, are heavily glycosylated proteins that polymerise and retain water molecules, resulting in a hydrated biogel. It is assumed that positively charged ions can influence mucin film structure by screening the electrostatic repulsions between the negatively charged glycans on mucin moieties and draw in water molecules via hydration shells. The ionic concentration can vary significantly in different mucus systems and here we show that increasing the ionic concentration in mucin films leads to an increase in lubrication between two polydimethylsiloxane surfaces at sliding contact in a compliant oral mimic. Mucins were found to bind sodium ions in a concentration-dependent manner and increased ionic concentration appears to cause mucin films to swell when assessed by Quartz Crystal hiMicrobalance with Dissipation (QCM-D) analysis. Furthermore, we determined that the removal of negatively charged sialic acid moieties by sialidase digestion resulted in reduced adsorption to hydrophilic surfaces but did not affect the swelling of mucin films with increasing ionic concentrations. Moreover, the coefficient of friction was increased with sialic acid removal, but lubrication was still increased with increasing ionic concentrations. Taken together this suggests that sialic acids are important for lubrication and may exert this through the sacrificial layer mechanism. Ionic concentration appears to influence mucin films and their lubrication, and sialic acids, at least partly, may be important for ion binding.
Collapse
Affiliation(s)
- Abby Weston
- Centre for Host Microbiome Interactions, Salivary Research, Faculty of Dentistry, Oral and Craniofacial Science, King's College London, London, UK.
| | - Sorin-Cristian Vladescu
- Department of Mechanical Engineering, Imperial College London, South Kensington Campus, London, UK
| | - Tom Reddyhoff
- Department of Mechanical Engineering, Imperial College London, South Kensington Campus, London, UK
| | - Alex Griffiths
- London Metallomics Facility, King's College London, Waterloo Campus, London, UK
| | - Thomas Crouzier
- Division of Glycoscience, KTH Royal Institute of Technology, Albanova Unversity Centre, Stockholm, Sweden
| | - Matthew Fielden
- Division of Surface and Corrosion Science, KTH Royal Institute of Technology, Albanova University Centre, Stockholm, Sweden
| | - James A Garnett
- Centre for Host Microbiome Interactions, Salivary Research, Faculty of Dentistry, Oral and Craniofacial Science, King's College London, London, UK
| | - Guy H Carpenter
- Centre for Host Microbiome Interactions, Salivary Research, Faculty of Dentistry, Oral and Craniofacial Science, King's College London, London, UK
| |
Collapse
|
3
|
d'Amone L, Sahoo JK, Ostrovsky-Snider N, Kaplan DL, Omenetto FG. Boronic Acid-Tethered Silk Fibroin for pH-Dependent Mucoadhesion. Biomacromolecules 2023; 24:1310-1317. [PMID: 36763594 DOI: 10.1021/acs.biomac.2c01349] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Abstract
Mucus lines all surfaces of the human body not covered by skin and provides lubrication, hydration, and protection. The properties of mucus are influenced by changes in pH that may occur due to physiological conditions and pathological circumstances. Reinforcing the mucus barrier with biopolymers that can adhere to mucus in different conditions can be a useful strategy for protecting the underlying mucosae from damage. In this work, regenerated silk fibroin (silk) was chemically modified with phenyl boronic acid to form reversible covalent complexes with the 1,2- or 1,3-diols. The silk modified with boronic acid pendant groups has an increased affinity for mucins, whose carbohydrate component is rich in diols. These results offer new applications of silk in mucoadhesion, and the ability to bind diols to the silk lays the foundation for the development of silk-based sugar-sensing platforms.
Collapse
Affiliation(s)
- Luciana d'Amone
- Department of Biomedical Engineering, Tufts University, Medford, Massachusetts 02153, United States
| | - Jugal Kishore Sahoo
- Department of Biomedical Engineering, Tufts University, Medford, Massachusetts 02153, United States
| | | | - David L Kaplan
- Department of Biomedical Engineering, Tufts University, Medford, Massachusetts 02153, United States
| | - Fiorenzo G Omenetto
- Department of Biomedical Engineering, Tufts University, Medford, Massachusetts 02153, United States
- Department of Electrical and Computer Engineering, Tufts University, Medford, Massachusetts 02153, United States
- Department of Physics, Tufts University, Medford, Massachusetts 02153, United States
- Laboratory for Living Devices, Tufts University, Medford, Massachusetts 02153, United States
| |
Collapse
|
4
|
Duanis-Assaf T, Hu T, Lavie M, Zhang Z, Reches M. Understanding the Adhesion Mechanism of Hydroxyapatite-Binding Peptide. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2022; 38:968-978. [PMID: 34995466 PMCID: PMC8793143 DOI: 10.1021/acs.langmuir.1c02293] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2021] [Revised: 12/21/2021] [Indexed: 05/31/2023]
Abstract
Understanding the interactions between the protein collagen and hydroxyapatite is of high importance for understanding biomineralization and bone formation. Here, we undertook a reductionist approach and studied the interactions between a short peptide and hydroxyapatite. The peptide was selected from a phage-display library for its high affinity to hydroxyapatite. To study its interactions with hydroxyapatite, we performed an alanine scan to determine the contribution of each residue. The interactions of the different peptide derivatives were studied using a quartz crystal microbalance with dissipation monitoring and with single-molecule force spectroscopy by atomic force microscopy. Our results suggest that the peptide binds via electrostatic interactions between cationic moieties of the peptide and the negatively charged groups on the crystal surface. Furthermore, our findings show that cationic residues have a crucial role in binding. Using molecular dynamics simulations, we show that the peptide structure is a contributing factor to the adhesion mechanism. These results suggest that even small conformational changes can have a significant effect on peptide adhesion. We suggest that a bent structure of the peptide allows it to strongly bind hydroxyapatite. The results presented in this study improve our understanding of peptide adhesion to hydroxyapatite. On top of physical interactions between the peptide and the surface, peptide structure contributes to adhesion. Unveiling these processes contributes to our understanding of more complex biological systems. Furthermore, it may help in the design of de novo peptides to be used as functional groups for modifying the surface of hydroxyapatite.
Collapse
Affiliation(s)
- Tal Duanis-Assaf
- Institute
of Chemistry and The Center for Nanoscience and Nanotechnology, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Tan Hu
- Institute
of Chemistry and The Center for Nanoscience and Nanotechnology, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
- College
of Food Science and Technology, Huazhong
Agricultural University, Wuhan, Hubei 430070, People’s Republic of China
- Key
Laboratory of Environment Correlative Dietology, Huazhong Agricultural
University, Ministry of Education, Wuhan, Hubei 430070, People’s Republic of China
| | - Maayan Lavie
- Institute
of Chemistry and The Center for Nanoscience and Nanotechnology, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Zhuo Zhang
- College
of Food Science and Technology, Huazhong
Agricultural University, Wuhan, Hubei 430070, People’s Republic of China
- Key
Laboratory of Environment Correlative Dietology, Huazhong Agricultural
University, Ministry of Education, Wuhan, Hubei 430070, People’s Republic of China
| | - Meital Reches
- Institute
of Chemistry and The Center for Nanoscience and Nanotechnology, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| |
Collapse
|
5
|
Marczynski M, Kimna C, Lieleg O. Purified mucins in drug delivery research. Adv Drug Deliv Rev 2021; 178:113845. [PMID: 34166760 DOI: 10.1016/j.addr.2021.113845] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Revised: 06/02/2021] [Accepted: 06/16/2021] [Indexed: 12/20/2022]
Abstract
One of the main challenges in the field of drug delivery remains the development of strategies to efficiently transport pharmaceuticals across mucus barriers, which regulate the passage and retention of molecules and particles in all luminal spaces of the body. A thorough understanding of the molecular mechanisms, which govern such selective permeability, is key for achieving efficient translocation of drugs and drug carriers. For this purpose, model systems based on purified mucins can contribute valuable information. In this review, we summarize advances that were made in the field of drug delivery research with such mucin-based model systems: First, we give an overview of mucin purification procedures and discuss the suitability of model systems reconstituted from purified mucins to mimic native mucus. Then, we summarize techniques to study mucin binding. Finally, we highlight approaches that made use of mucins as building blocks for drug delivery platforms or employ mucins as active compounds.
Collapse
|
6
|
Lopes-de-Campos D, Pinto RM, Lima SAC, Santos T, Sarmento B, Nunes C, Reis S. Delivering amoxicillin at the infection site - a rational design through lipid nanoparticles. Int J Nanomedicine 2019; 14:2781-2795. [PMID: 31114195 PMCID: PMC6488159 DOI: 10.2147/ijn.s193992] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Purpose Amoxicillin is a commonly used antibiotic, although degraded by the acidic pH of the stomach. This is an important limitation for the treatment of Helicobacter pylori infections. The purpose of this work was to encapsulate amoxicillin in lipid nanoparticles, increasing the retention time at the site of infection (gastric mucosa), while protecting the drug from the harsh conditions of the stomach lumen. Materials and methods The nanoparticles were produced by the double emulsion technique and optimized by a three-level Box-Behnken design. Tween 80 and linolenic acid were used as potential therapeutic adjuvants and dioleoylphosphatidylethanolamine as a targeting agent to Helicobacter pylori. Nanoparticles were characterized regarding their physico-chemical features, their storage stability, and their usability for oral administration (assessment of in vitro release, in vitro cell viability, permeability, and interaction with mucins). Results The nanoparticles were stable for at least 6 months at 4°C. In vitro release studies revealed a high resistance to harsh conditions, including acidic pH and physiologic temperature. The nanoparticles have a low cytotoxicity effect in both fibroblasts and gastric cell lines, and they have the potential to be retained at the gastric mucosa. Conclusion Overall, the designed formulations present suitable physico-chemical features for being henceforward used by oral administration to treat Helicobacter pylori infections.
Collapse
Affiliation(s)
- Daniela Lopes-de-Campos
- LAQV, REQUIMTE, Departamento de Ciências Químicas, Faculdade de Farmácia, Universidade do Porto, Porto, Portugal,
| | - Rita M Pinto
- LAQV, REQUIMTE, Departamento de Ciências Químicas, Faculdade de Farmácia, Universidade do Porto, Porto, Portugal,
| | - Sofia A Costa Lima
- LAQV, REQUIMTE, Departamento de Ciências Químicas, Faculdade de Farmácia, Universidade do Porto, Porto, Portugal,
| | - Tiago Santos
- INEB - Instituto de Engenharia Biomédica, Universidade do Porto, Porto, Portugal.,i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
| | - Bruno Sarmento
- INEB - Instituto de Engenharia Biomédica, Universidade do Porto, Porto, Portugal.,i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal.,IINFACTS, Instituto de Investigação e Formação Avançada em Ciências e Tecnologias da Saúde, Instituto Universitário de Ciências da Saúde, Gandra, Portugal
| | - Cláudia Nunes
- LAQV, REQUIMTE, Departamento de Ciências Químicas, Faculdade de Farmácia, Universidade do Porto, Porto, Portugal,
| | - Salette Reis
- LAQV, REQUIMTE, Departamento de Ciências Químicas, Faculdade de Farmácia, Universidade do Porto, Porto, Portugal,
| |
Collapse
|
7
|
QCM-D characterization of time-dependence of bacterial adhesion. ACTA ACUST UNITED AC 2019; 5:100024. [PMID: 32743140 PMCID: PMC7389184 DOI: 10.1016/j.tcsw.2019.100024] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Revised: 01/29/2019] [Accepted: 03/29/2019] [Indexed: 12/22/2022]
Abstract
Quartz crystal microbalance with dissipation monitoring (QCM-D) is becoming an increasingly popular technique that can be employed as part of experimental and modeling investigations of bacterial adhesion. The usefulness of QCM-D derives from this technique's ability to probe binding and interactions under dynamic conditions, in real time. Bacterial adhesion is an important first step in the formation of biofilms, the control of which is relevant to industries that include shipping, water purification, packaging, and biomedical devices. However, many questions remain unanswered in the bacterial adhesion process, despite extensive research in this area. With QCM-D, multiple variables affecting bacterial adhesion can be studied, including the roles of substrate composition, chemical modification, solution ionic strength, environmental temperature, shear conditions, and time. Recent studies demonstrate the utility of QCM-D in developing new bacterial adhesion models and studying different stages of biofilm formation. We provide a review of how QCM-D has been used to study bacterial adhesion at stages ranging from the first step of bacterial adhesion to mature biofilms, and how QCM-D studies are being used to promote the development of solutions to biofilm formation.
Collapse
|
8
|
Wan F, Nylander T, Foged C, Yang M, Baldursdottir SG, Nielsen HM. Qualitative and quantitative analysis of the biophysical interaction of inhaled nanoparticles with pulmonary surfactant by using quartz crystal microbalance with dissipation monitoring. J Colloid Interface Sci 2019; 545:162-171. [PMID: 30877998 DOI: 10.1016/j.jcis.2019.02.088] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2018] [Revised: 02/25/2019] [Accepted: 02/26/2019] [Indexed: 11/28/2022]
Abstract
Understanding the interaction between inhaled nanoparticles and pulmonary surfactant is a prerequisite for predicting the fate of inhaled nanoparticles. Here, we introduce a quartz crystal microbalance with dissipation monitoring (QCM-D)-based methodology to reveal the extent and nature of the biophysical interactions of polymer- and lipid-based nanoparticles with pulmonary surfactant. By fitting the QCM-D data to the Langmuir adsorption equation, we determined the kinetics and equilibrium parameters [i.e., maximal adsorption (Δmmax), equilibrium constant (Ka), adsorption rate constant (ka) and desorption rate constant (kd)] of polymeric nanoparticles adsorption onto the pulmonary surfactant (e.g., an artificial lipid mixture and an extract of porcine lung surfactant). Furthermore, our results revealed that the nature of the interactions between lipid-based nanoparticles (e.g., liposomes) and pulmonary surfactant was governed by the liposomal composition, i.e., incorporation of cholesterol and PEGylated phospholipid (DSPE-PEG2000) into DOPC-based liposomes led to the adsorption of intact liposomes onto the pulmonary surfactant layer and the mass exchange between the liposomes and pulmonary surfactant layer, respectively. In conclusion, we demonstrate the applicability of the QCM-D technique for qualitative and quantitative analysis of the biophysical interaction of inhaled nanoparticles with pulmonary surfactant, which is vital for rational design and optimization of inhalable nanomedicines.
Collapse
Affiliation(s)
- Feng Wan
- Department of Pharmacy, University of Copenhagen, Universitetsparken 2, 2100 Copenhagen Ø, Denmark
| | - Tommy Nylander
- Department of Physical Chemistry, Lund University, SE-221 00 Lund, Sweden
| | - Camilla Foged
- Department of Pharmacy, University of Copenhagen, Universitetsparken 2, 2100 Copenhagen Ø, Denmark
| | - Mingshi Yang
- Department of Pharmacy, University of Copenhagen, Universitetsparken 2, 2100 Copenhagen Ø, Denmark
| | - Stefania G Baldursdottir
- Department of Pharmacy, University of Copenhagen, Universitetsparken 2, 2100 Copenhagen Ø, Denmark
| | - Hanne M Nielsen
- Department of Pharmacy, University of Copenhagen, Universitetsparken 2, 2100 Copenhagen Ø, Denmark.
| |
Collapse
|
9
|
Jia W, Tian J, Bai P, Li S, Zeng H, Zhang W, Tian Y. A novel comb-typed poly(oligo(ethylene glycol) methylether acrylate) as an excellent aqueous lubricant. J Colloid Interface Sci 2018; 539:342-350. [PMID: 30594009 DOI: 10.1016/j.jcis.2018.12.085] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Revised: 12/22/2018] [Accepted: 12/22/2018] [Indexed: 11/16/2022]
Abstract
HYPOTHESIS Aqueous lubricants exhibit versatile advantages over oil-based lubricants. However, it still remains a challenge for the aqueous solutions to obtain excellent lubrication properties with high contact pressure on macroscale. EXPERIMENTS In this work, a comb-typed poly(oligo(ethylene glycol) methylether acrylate) (P(OEGMA)) was successfully synthesized via RAFT polymerization. Rheological, morphological and tribological properties of prepared P(OEGMA) aqueous solutions were characterized via a rheometer, cryo-SEM and ball-on-disk tribometer, respectively. FINDINGS The synthesized P(OEGMA) exhibited a uniformly smaller size than that of the commercial linear polyethylene glycol (PEG), leading to reduced viscosities in aqueous solutions. The obtained P(OEGMA) aqueous solutions achieved outstandingly ultralow friction coefficients (μ < 0.01) and a good wear-resistance under high pressure (>300 MPa, two-fold increase than reported in the previous literature). The desirable lubricating performances can be attributed to the well-established running-in period, a good interfacial adsorption property between polymer molecules and solid surfaces, the hydration effect as well as the hydrodynamic effect. The current finding reveals the excellent aqueous lubrication properties possessed by the synthesized comb-typed P(OEGMA), which can broaden the development of aqueous lubricants in practical engineering fields.
Collapse
Affiliation(s)
- Wenpeng Jia
- State Key Laboratory of Tribology, Department of Mechanical Engineering, Tsinghua University, Beijing 100084, China
| | - Jinmi Tian
- College of Materials Science and Engineering, Qingdao University, Qingdao 266071, China
| | - Pengpeng Bai
- State Key Laboratory of Tribology, Department of Mechanical Engineering, Tsinghua University, Beijing 100084, China
| | - Shaowei Li
- State Key Laboratory of Tribology, Department of Mechanical Engineering, Tsinghua University, Beijing 100084, China
| | - Hongbo Zeng
- Department of Chemical and Materials Engineering, University of Alberta, Edmonton, Alberta T6G 1H9, Canada
| | - Wenling Zhang
- Department of Chemical and Materials Engineering, University of Alberta, Edmonton, Alberta T6G 1H9, Canada.
| | - Yu Tian
- State Key Laboratory of Tribology, Department of Mechanical Engineering, Tsinghua University, Beijing 100084, China.
| |
Collapse
|
10
|
Modified Protein Misfolding Cyclic Amplification Overcomes Real-Time Quaking-Induced Conversion Assay Inhibitors in Deer Saliva To Detect Chronic Wasting Disease Prions. J Clin Microbiol 2018; 56:JCM.00947-18. [PMID: 29950332 DOI: 10.1128/jcm.00947-18] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2018] [Accepted: 06/18/2018] [Indexed: 01/19/2023] Open
Abstract
Chronic wasting disease (CWD), a fatal neurodegenerative prion disease of cervids, has spread across North America and has been detected in The Republic of Korea, Finland, and Norway. CWD appears to spread by horizontal transmission, and prions shed in saliva, feces, and urine are thought to contribute. However, studies investigating the rapid spread of CWD have been hampered by assay inhibitors and a lack of consistent and sensitive means to detect the relatively low levels of prions in these samples. Here we show that saliva frequently contains an inhibitor of the real-time quaking-induced conversion assay (RT-QuIC) and that the inhibitor is a member of the mucin family. To circumvent the inhibitor, we developed a modified protein misfolding cyclic amplification (PMCA) method to amplify CWD prions in saliva that were undetectable or ambiguous by RT-QuIC. Our results reinforce the impact of saliva in horizontal CWD transmission and highlight the importance of detection optimization.
Collapse
|
11
|
Wordofa DN, Ramnani P, Tran TT, Mulchandani A. An oligonucleotide-functionalized carbon nanotube chemiresistor for sensitive detection of mercury in saliva. Analyst 2018; 141:2756-60. [PMID: 26902487 DOI: 10.1039/c6an00018e] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Divalent mercuric (Hg(2+)) ion and monomethyl mercury (CH3Hg(+)) are two forms of mercury that are known to be highly toxic to humans. In this work, we present a highly selective, sensitive and label-free chemiresistive biosensor for the detection of both, Hg(2+) and CH3Hg(+) ions using DNA-functionalized single-walled carbon nanotubes (SWNTs). The SWNTs were functionalized with the capture oligonucleotide, polyT, using a linker molecule. The polyT was hybridized with polyA to form a polyT:polyA duplex. Upon exposure to mercury ions, the polyT:polyA duplex dehybridizes and a T-Hg(2+)-T duplex is formed. This structure switch leads to the release of polyA from the SWNT surface and correspondingly a change in the resistance of the chemiresistive biosensor is observed, which is used to quantify the mercury ion concentration. The biosensor showed a wide dynamic range of 0.5 to 100 nM for the detection of CH3Hg(+) ions in buffer solution with a sensitivity of 28.34% per log (nM) of CH3Hg(+). Finally, real world application of the biosensor was demonstrated by the detection of Hg(2+) and CH3Hg(+) ions in simulated saliva samples spiked with a known concentration of mercury ions.
Collapse
Affiliation(s)
- Dawit N Wordofa
- Department of Chemical and Environmental Engineering, University of California, Riverside, California 92521, USA.
| | - Pankaj Ramnani
- Department of Chemical and Environmental Engineering, University of California, Riverside, California 92521, USA.
| | - Thien-Toan Tran
- Department of Bioengineering, University of California, Riverside, California 92521, USA
| | - Ashok Mulchandani
- Department of Chemical and Environmental Engineering, University of California, Riverside, California 92521, USA. and Material Science and Engineering Program, University of California, Riverside, California 92521, USA
| |
Collapse
|
12
|
Elzoghby AO, El-Lakany SA, Helmy MW, Abu-Serie MM, Elgindy NA. Shell-crosslinked zein nanocapsules for oral codelivery of exemestane and resveratrol in breast cancer therapy. Nanomedicine (Lond) 2017; 12:2785-2805. [DOI: 10.2217/nnm-2017-0247] [Citation(s) in RCA: 62] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Aim: Oral administration of exemestane (EXM) and resveratrol (RES) for breast cancer therapy has been limited by their poor solubility and low permeability. Methods: In this study, these issues were tackled using zein nanocapsules (ZNCs) for oral EXM/RES codelivery combining drug solubilization within oily core and resistance to digestion via hydrophobic protein shell. Furthermore, higher oral stability and sustained release could be enabled by glutaraldehyde crosslinking of zein shell. Results & conclusion: EXM/RES-ZNCs showed enhanced cytotoxicity against MCF-7 and 4T1 breast cancer cells compared with free drug combination with higher selectivity to cancer cells rather than normal fibroblasts. In vivo, crosslinked EXM/RES-ZNCs markedly reduced the percentage increase of Ehrlich ascites mammary tumor volume in mice by 2.4-fold compared with free drug combination.
Collapse
Affiliation(s)
- Ahmed O Elzoghby
- Cancer Nanotechnology Research Laboratory (CNRL), Faculty of Pharmacy, Alexandria University, Alexandria 21521, Egypt
- Department of Industrial Pharmacy, Faculty of Pharmacy, Alexandria University, Alexandria 21521, Egypt
| | - Sarah A El-Lakany
- Department of Industrial Pharmacy, Faculty of Pharmacy, Alexandria University, Alexandria 21521, Egypt
| | - Maged W Helmy
- Cancer Nanotechnology Research Laboratory (CNRL), Faculty of Pharmacy, Alexandria University, Alexandria 21521, Egypt
- Department of Pharmacology & Toxicology, Faculty of Pharmacy, Damanhour University, Damanhour, Egypt
| | - Marwa M Abu-Serie
- Medical Biotechnology Department, Genetic Engineering & Biotechnology Research Institute, City of Scientific Research & Technological Applications, New-Borg El-Arab City, Alexandria 21934, Egypt
| | - Nazik A Elgindy
- Department of Industrial Pharmacy, Faculty of Pharmacy, Alexandria University, Alexandria 21521, Egypt
| |
Collapse
|
13
|
Madsen JB, Pakkanen KI, Duelund L, Svensson B, Hachem MA, Lee S. A simplified chromatographic approach to purify commercially available bovine submaxillary mucins (BSM). Prep Biochem Biotechnol 2015; 45:84-99. [PMID: 24547990 DOI: 10.1080/10826068.2014.887583] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
In this study, a simple purification protocol is developed to reduce the bovine serum albumin (BSA) content in commercially available bovine submaxillary mucin (BSM). This involved purification of the BSM by one-column anion-exchange chromatography protocol resulting in BSM with greatly reduced BSA content and homogeneously distributed size, and in a high yield of ∼43% from BSM as received from the manufacturer. The purity and composition of commercially acquired BSM were assessed by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and mass spectrometry, which verified that BSA is the most abundant nonmucinous protein component. The purification effect was evident from a significantly altered circular dichroism (CD) spectrum of BSM after anion-exchange chromatography.
Collapse
Affiliation(s)
- Jan Busk Madsen
- a Department of Mechanical Engineering , Technical University of Denmark , Kgs. Lyngby , Denmark
| | | | | | | | | | | |
Collapse
|
14
|
Ahn J, Crouzier T, Ribbeck K, Rubner MF, Cohen RE. Tuning the Properties of Mucin via Layer-by-Layer Assembly. Biomacromolecules 2014; 16:228-35. [DOI: 10.1021/bm5014475] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Jiyoung Ahn
- Department of Chemical Engineering, ‡Department of Biological Engineering, and §Department of
Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Thomas Crouzier
- Department of Chemical Engineering, ‡Department of Biological Engineering, and §Department of
Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Katharina Ribbeck
- Department of Chemical Engineering, ‡Department of Biological Engineering, and §Department of
Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Michael F. Rubner
- Department of Chemical Engineering, ‡Department of Biological Engineering, and §Department of
Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Robert E. Cohen
- Department of Chemical Engineering, ‡Department of Biological Engineering, and §Department of
Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| |
Collapse
|
15
|
Visnevskij C, Ciuta G, Ketleriute S, Savickaite M, Makuska R. ISARA ATRP of methacrylic acid neutralized by simple amines yielding linear polymers and anionic molecular brushes. Eur Polym J 2014. [DOI: 10.1016/j.eurpolymj.2014.03.031] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
|
16
|
Patterned monomolecular films from polymerizable and fluorinated lipids for the presentation of glycosylated lipids. Colloid Polym Sci 2014. [DOI: 10.1007/s00396-014-3237-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
|
17
|
An J, Dėdinaitė A, Nilsson A, Holgersson J, Claesson PM. Comparison of a Brush-with-Anchor and a Train-of-Brushes Mucin on Poly(methyl methacrylate) Surfaces: Adsorption, Surface Forces, and Friction. Biomacromolecules 2014; 15:1515-25. [DOI: 10.1021/bm500173s] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Junxue An
- School
of Chemical Science and Engineering, Department of Chemistry, Division
of Surface and Corrosion Science, KTH Royal Institute of Technology, Drottning Kristinas väg 51, SE-100 44 Stockholm, Sweden
| | - Andra Dėdinaitė
- School
of Chemical Science and Engineering, Department of Chemistry, Division
of Surface and Corrosion Science, KTH Royal Institute of Technology, Drottning Kristinas väg 51, SE-100 44 Stockholm, Sweden
- Chemistry,
Materials and Surfaces, SP Technical Research Institute of Sweden, P. O. Box 5607, SE-114 86 Stockholm, Sweden
| | - Anki Nilsson
- Recopharma
AB, Arvid Wallgrens backe 20, 413 46 Gothenburg, Sweden
| | - Jan Holgersson
- Department
of Clinical Chemistry and Transfusion Medicine, The Sahlgrenska Academy, University of Gothenburg and Sahlgrenska University Hospital, Vita stråket
13, SE-413 45 Gothenburg, Sweden
| | - Per M. Claesson
- School
of Chemical Science and Engineering, Department of Chemistry, Division
of Surface and Corrosion Science, KTH Royal Institute of Technology, Drottning Kristinas väg 51, SE-100 44 Stockholm, Sweden
- Chemistry,
Materials and Surfaces, SP Technical Research Institute of Sweden, P. O. Box 5607, SE-114 86 Stockholm, Sweden
| |
Collapse
|
18
|
|
19
|
Crouzier T, Jang H, Ahn J, Stocker R, Ribbeck K. Cell patterning with mucin biopolymers. Biomacromolecules 2013; 14:3010-6. [PMID: 23980712 DOI: 10.1021/bm400447z] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The precise spatial control of cell adhesion to surfaces is an endeavor that has enabled discoveries in cell biology and new possibilities in tissue engineering. The generation of cell-repellent surfaces currently requires advanced chemistry techniques and could be simplified. Here we show that mucins, glycoproteins of high structural and chemical complexity, spontaneously adsorb on hydrophobic substrates to form coatings that prevent the surface adhesion of mammalian epithelial cells, fibroblasts, and myoblasts. These mucin coatings can be patterned with micrometer precision using a microfluidic device, and are stable enough to support myoblast differentiation over seven days. Moreover, our data indicate that the cell-repellent effect is dependent on mucin-associated glycans because their removal results in a loss of effective cell-repulsion. Last, we show that a critical surface density of mucins, which is required to achieve cell-repulsion, is efficiently obtained on hydrophobic surfaces, but not on hydrophilic glass surfaces. However, this limitation can be overcome by coating glass with hydrophobic fluorosilane. We conclude that mucin biopolymers are attractive candidates to control cell adhesion on surfaces.
Collapse
Affiliation(s)
- T Crouzier
- Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | | | | | | | | |
Collapse
|
20
|
Krivosheeva O, Sababi M, Dedinaite A, Claesson PM. Nanostructured composite layers of mussel adhesive protein and ceria nanoparticles. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2013; 29:9551-9561. [PMID: 23815752 DOI: 10.1021/la401693x] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Mussel adhesive proteins are known for their high affinity to a range of different surfaces, and they therefore appear as ideal candidates for producing thin inorganic-organic composite films with high robustness. In this work we explore the possibility of making cohesive films utilizing layer-by-layer deposition of the highly positively charged mussel adhesive protein, Mefp-1, and negatively charged ceria nanoparticles. This particular material combination was chosen due to recent findings that such films provide good corrosion protection. Quartz crystal microbalance with dissipation monitoring (QCM-D) was used for following the film formation process in situ on silica surfaces. A close to linear growth of the film with number of deposited layers was found for up to 18 deposition steps, the highest number of depositions investigated in this work. The Mefp-1 concentration during film deposition affected the film properties, where a higher protein concentration resulted in a stiffer film. It was also found that the added mass could be amplified by using a Mefp-1 solution containing small aggregates. The surface nanomechanical properties of dried multilayer films were investigated using peak force QNM (quantitative nanomechanical mapping) in air. Homogeneous surface coverage was found under all conditions explored, and the Young's modulus of the outer region of the coating increased when a higher Mefp-1 concentration was used during film deposition. The nature of the outermost surface layer was found to significantly affect the surface nanomechanical properties. The abrasion resistance of the coating was measured by using controlled-force contact mode AFM.
Collapse
Affiliation(s)
- Olga Krivosheeva
- Division of Surface and Corrosion Science, Department of Chemistry, School of Chemical Sciences, Royal Institute of Technology, SE-100 44 Stockholm, Sweden
| | | | | | | |
Collapse
|
21
|
Bravo-Osuna I, Noiray M, Briand E, Woodward AM, Argüeso P, Molina Martínez IT, Herrero-Vanrell R, Ponchel G. Interfacial interaction between transmembrane ocular mucins and adhesive polymers and dendrimers analyzed by surface plasmon resonance. Pharm Res 2012; 29:2329-40. [PMID: 22565639 DOI: 10.1007/s11095-012-0761-1] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2011] [Accepted: 04/17/2012] [Indexed: 11/27/2022]
Abstract
PURPOSE Development of the first in vitro method based on biosensor chip technology designed for probing the interfacial interaction phenomena between transmembrane ocular mucins and adhesive polymers and dendrimers intended for ophthalmic administration. METHODS The surface plasmon resonance (SPR) technique was used. A transmembrane ocular mucin surface was prepared on the chip surface and characterized by QCM-D (Quartz Crystal Microbalance with Dissipation) and XPS (X-ray photoelectron spectroscopy). The mucoadhesive molecules tested were: hyaluronic acid (HA), carboxymethyl cellulose (CMC), hydroxypropylmethyl cellulose (HPMC), chitosan (Ch) and polyamidoamine dendrimers (PAMAM). RESULTS While Ch originated interfacial interaction with ocular transmembrane mucins, for HA, CMC and HPMC, chain interdiffusion seemed to be mandatory for bioadherence at the concentrations used in ophthalmic clinical practise. Interestingly, PAMAM dendrimers developed permanent interfacial interactions with transmembrane ocular mucins whatever their surface chemical groups, showing a relevant importance of co-operative effect of these multivalent systems. Polymers developed interfacial interactions with ocular membrane-associated mucins in the following order: Ch(1 %) > G4PAMAM-NH(2)(2 %) = G4PAMAM-OH(2 %) > G3.5PAMAM-COOH(2 %)>> CMC(0.5 %) = HA(0.2 %) = HPMC(0.3 %). CONCLUSIONS The method proposed is useful to discern between the mucin-polymer chemical interactions at molecular scale. Results reinforce the usefulness of chitosan and dendrimers as polymers able to increase the retention time of drugs on the ocular surface and hence their bioavailability.
Collapse
Affiliation(s)
- I Bravo-Osuna
- Department of Pharmacy & Pharmaceutical Technology, School of Pharmacy, University Complutense of Madrid (UCM), Madrid, Spain.
| | | | | | | | | | | | | | | |
Collapse
|
22
|
Wang B, Liu Z, Xu Y, Li Y, An T, Su Z, Peng B, Lin Y, Wang Q. Construction of glycoprotein multilayers using the layer-by-layer assembly technique. ACTA ACUST UNITED AC 2012. [DOI: 10.1039/c2jm33070a] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
|
23
|
Becker B, Cooper MA. A survey of the 2006-2009 quartz crystal microbalance biosensor literature. J Mol Recognit 2011; 24:754-87. [DOI: 10.1002/jmr.1117] [Citation(s) in RCA: 138] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
|
24
|
Baldrich E, Muñoz FX, García-Aljaro C. Electrochemical Detection of Quorum Sensing Signaling Molecules by Dual Signal Confirmation at Microelectrode Arrays. Anal Chem 2011; 83:2097-103. [DOI: 10.1021/ac1028243] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Eva Baldrich
- Institut de Microelectrònica de Barcelona (IMB-CNM), CSIC, Campus UAB, 08193 Bellaterra, Barcelona, Spain
| | - Francesc Xavier Muñoz
- Institut de Microelectrònica de Barcelona (IMB-CNM), CSIC, Campus UAB, 08193 Bellaterra, Barcelona, Spain
| | - Cristina García-Aljaro
- Departament de Microbiologia, Facultat de Biologia, Universitat de Barcelona, Av. Diagonal, 645, Barcelona 08028, Spain
| |
Collapse
|
25
|
Svensson O, Arnebrant T. Mucin layers and multilayers — Physicochemical properties and applications. Curr Opin Colloid Interface Sci 2010. [DOI: 10.1016/j.cocis.2010.05.015] [Citation(s) in RCA: 73] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
26
|
Coles JM, Chang DP, Zauscher S. Molecular mechanisms of aqueous boundary lubrication by mucinous glycoproteins. Curr Opin Colloid Interface Sci 2010. [DOI: 10.1016/j.cocis.2010.07.002] [Citation(s) in RCA: 113] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
|
27
|
Tlili C, Cella LN, Myung NV, Shetty V, Mulchandani A. Single-walled carbon nanotube chemoresistive label-free immunosensor for salivary stress biomarkers. Analyst 2010; 135:2637-42. [PMID: 20694207 DOI: 10.1039/c0an00332h] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
The present work is focused on the development, analytical characterization and evaluation of selective and sensitive SWNT-chemiresistor immunosensor for the label-free detection of salivary α-amylase (SAA). SWNTs were aligned to bridge lithographically patterned gold microelectrodes using AC dielectrophoresis followed by functionalization with anti-SAA antibodies. The nano-immunosensors exhibited excellent sensitivity over the clinically relevant range (19 to 308 U ml(-1)) with a limit of detection (LOD) of 6 µg ml(-1) (0.6 U ml(-1)) and 7.8 µg ml(-1) (0.78 U ml(-1)) in phosphate buffer and artificial saliva, respectively, and no interference from other components of saliva. This label-free nano-immunosensor technology has potential application in clinical diagnosis for stress biomarkers expressed in human saliva at the point-of-care.
Collapse
Affiliation(s)
- Chaker Tlili
- Department of Chemical and Environmental Engineering, University of California, Riverside, California 92521, USA
| | | | | | | | | |
Collapse
|
28
|
Halthur TJ, Arnebrant T, Macakova L, Feiler A. Sequential adsorption of bovine mucin and lactoperoxidase to various substrates studied with quartz crystal microbalance with dissipation. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2010; 26:4901-4908. [PMID: 20184356 DOI: 10.1021/la902267c] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Mucin and lactoperoxidase are both natively present in the human saliva. Mucin provides lubricating and antiadhesive function, while lactoperoxidase has antimicrobial activity. We propose that combined films of the two proteins can be used as a strategy for surface modification in biomedical applications such as implants or biosensors. In order to design and ultilize mixed protein films, it is necessary to understand the variation in adsorption behavior of the proteins onto different surfaces and how it affects their interaction. The quartz crystal microbalance with dissipation (QCM-D) technique has been used to extract information of the adsorption properties of bovine mucin (BSM) and lactoperoxidase (LPO) to gold, silica, and hydrophobized silica surfaces. The information has further been used to retrieve information of the viscoelastic properties of the adsorbed film. The adsorption and compaction of BSM were found to vary depending on the nature of the underlying bare surface, adsorbing as a thick highly hydrated film with loops and tails extending out in the bulk on gold and as a thinner film with much lower adsorbed amount on silica; and on hydrophobic surfaces, BSM adsorbs as a flat and much more compact layer. On gold and silica, the highly hydrated BSM film is cross-linked and compacted by the addition of LPO, whereas the compaction is not as pronounced on the already more compact film formed on hydrophobic surfaces. The adsorption of LPO to bare surfaces also varied depending on the type of surface. The adsorption profile of BSM onto LPO-coated surfaces mimicked the adsorption to the underlying surface, implying little interaction between the LPO and BSM. The interaction between the protein layers was interpreted as a combination of electrostatic and hydrophobic interactions, which was in turn influenced by the interaction of the proteins with the different substrates.
Collapse
Affiliation(s)
- Tobias J Halthur
- Biomedical Laboratory Science and Technology, Faculty of Health and Society, Malmö University, SE-205 06 Malmö, Sweden.
| | | | | | | |
Collapse
|
29
|
Macakova L, Yakubov GE, Plunkett MA, Stokes JR. Influence of ionic strength changes on the structure of pre-adsorbed salivary films. A response of a natural multi-component layer. Colloids Surf B Biointerfaces 2010; 77:31-9. [PMID: 20133111 DOI: 10.1016/j.colsurfb.2009.12.022] [Citation(s) in RCA: 74] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2009] [Revised: 10/28/2009] [Accepted: 12/30/2009] [Indexed: 10/20/2022]
Abstract
Salivary films coating oral surfaces are critically important for oral health. This study focuses on determining the underlying nature of this adsorbed film and how it responds to departures from physiological conditions due to changes in ionic strength. Under physiological conditions, it is found that pre-adsorbed in vitro salivary film on hydrophobic surfaces is present as a highly hydrated viscoelastic layer. We follow the evolution of this film in terms of its effective thickness, hydration and viscoelastic properties, as well as adsorbed mass of proteins, using complementary surface characterisation methods: a Surface Plasmon Resonance (SPR) and a Quartz Crystal Microbalance with Dissipation Monitoring (QCM-D). Our results support a heterogeneous model for the structure of the salivary film with an inner dense anchoring layer and an outer highly extended hydrated layer. Further swelling of the film was observed upon decreasing the salt concentration down to 1mM NaCl. However, upon exposure to deionised water, a collapse of the film occurs that was associated with the loss of water contained within the adsorbed layer. We suggest that the collapse in deionised water is driven by an onset of electrostatic attraction between different parts of the multi-component salivary film. It is anticipated that such changes could also occur when the oral cavity is exposed to food, beverage, oral care and pharmaceutical formulations where drastic changes to the structural integrity of the film is likely to have implications on oral health, sensory perception and product performance.
Collapse
Affiliation(s)
- Lubica Macakova
- Unilever Discover, Colworth Science Park, Sharnbrook, Bedfordshire, United Kingdom.
| | | | | | | |
Collapse
|
30
|
|
31
|
Henricus MM, Fath KR, Menzenski MZ, Banerjee IA. Morphology Controlled Growth of Chitosan-Bound Microtubes and a Study of their Biocompatibility and Antibacterial Activity. Macromol Biosci 2009; 9:317-25. [DOI: 10.1002/mabi.200800220] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
32
|
Lundin M, Sandberg T, Caldwell KD, Blomberg E. Comparison of the adsorption kinetics and surface arrangement of "as received" and purified bovine submaxillary gland mucin (BSM) on hydrophilic surfaces. J Colloid Interface Sci 2009; 336:30-9. [PMID: 19442984 DOI: 10.1016/j.jcis.2009.03.061] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2009] [Revised: 03/26/2009] [Accepted: 03/26/2009] [Indexed: 11/18/2022]
Abstract
The effect of bovine serum albumin (BSA) as impurity in a commercial bovine submaxillary gland mucin preparation (BSM; Sigma M3895) on the adsorption of BSM to hydrophilic surfaces (mica and silica) has been studied in terms of adsorption kinetics, amount and structure of the formed adlayer. The Surface Force Apparatus (SFA) was used to gain information about the extended and compressed structure of adsorbed "as received" BSM, purified BSM, BSA extracted from the "as received" BSM and mixtures of the latter purified proteins. The adsorbed amount was estimated using a combination of X-ray Photoelectron Spectroscopy (XPS), Enzyme-Linked Immuno Sorbent Assay (ELISA), Enzyme-Linked Lectin Assay (ELLA), Dual Polarization Interferometry (DPI) and Quartz Crystal Microbalance (QCM-D) measurements. Under the used conditions, purified BSM showed very low affinity for silica and only small amounts were found to adsorb on mica. Initially, the BSM molecules adopted an extended conformation on the mica surface with tails extending into the bulk phase. These tails were irreversibly compressed into a very thin (10A) layer upon applying a high load. "As received" BSM formed considerably thicker compressed layers (35A); however, the extended layer structure was qualitatively the same. When mixtures of purified BSM and BSA were coadsorbed on mica, a 9wt-% albumin content gave a comparable layer thickness as the "as received" BSM and from XPS data we draw the conclusion that the albumin content in the layer adsorbed from "as received" BSM was approximately 5wt-%. Adsorption from an equal amount of BSM and BSA revealed that even though the amount of BSM is scarce in the mixed layer, the few BSM molecules have a drastic effect on the adsorbed thickness and structure. Clearly, this study shows the importance of characterizing the mucin used since differences in purity give rise to different adsorption behaviours in terms of both adsorbed amount and layer structure.
Collapse
Affiliation(s)
- Maria Lundin
- Surface and Corrosion Science, Department of Chemistry, Royal Institute of Technology, Drottning Kristinas väg 51, SE-10044 Stockholm, Sweden.
| | | | | | | |
Collapse
|