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Thirabowonkitphithan, P., Žalnėravičius, R., Shafaat, A., Jakubauskas, D., Neilands, J., Laiwattanapaisal, W. & Ruzgas, T. (2024). Electrogenicity of microbial biofilms of medically relevant microorganisms: potentiometric, amperometric and wireless detection.. Biosensors & bioelectronics, 246, Article ID 115892.
Open this publication in new window or tab >>Electrogenicity of microbial biofilms of medically relevant microorganisms: potentiometric, amperometric and wireless detection.
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2024 (English)In: Biosensors & bioelectronics, ISSN 0956-5663, E-ISSN 1873-4235, Vol. 246, article id 115892Article in journal (Refereed) Published
Abstract [en]

Since the progression of biofilm formation is related to the success of infection treatment, detecting microbial biofilms is of great interest. Biofilms of Gram-positive Staphylococcus aureus and Streptococcus gordonii bacteria, Gram-negative Pseudomonas aeruginosa and Escherichia coli bacteria, and Candida albicans yeast were examined using potentiometric, amperometric, and wireless readout modes in this study. As a biofilm formed, the open circuit potential (OCP) of biofilm hosting electrode (bioanode) became increasingly negative. Depending on the microorganism, the OCP ranged from −70 to −250 mV. The co-culture generated the most negative OCP (−300 mV vs Ag/AgCl), while the single-species biofilm formed by E. coli developed the least negative (−70 mV). The OCP of a fungal biofilm formed by C. albicans was −100 mV. The difference in electrode currents generated by biofilms was more pronounced. The current density of the S. aureus biofilm was 0.9‧10−7 A cm−2, while the value of the P. aeruginosa biofilm was 1.3‧10−6 A cm−2. Importantly, a biofilm formed by a co-culture of S. aureus and P. aeruginosa had a slightly higher negative OCP value and current density than the most electrogenic P. aeruginosa single-species biofilm. We present evidence that bacteria can share redox mediators found in multi-species biofilms. This synergy, enabling higher current and OCP values of multi-species biofilm hosting electrodes, could be beneficial for electrochemical detection of infectious biofilms in clinics. We demonstrate that the electrogenic biofilm can provide basis to construct novel wireless, chip-free, and battery-free biofilm detection method.

Place, publisher, year, edition, pages
Elsevier, 2024
Keywords
Biofilm detection, Microbial biosensor, Open circuit potential, Wireless biosensor
National Category
Microbiology
Identifiers
urn:nbn:se:mau:diva-64686 (URN)10.1016/j.bios.2023.115892 (DOI)001135565500001 ()38056343 (PubMedID)2-s2.0-85178667875 (Scopus ID)
Available from: 2023-12-21 Created: 2023-12-21 Last updated: 2024-02-05Bibliographically approved
Shafaat, A., Francisco Gonzalez-Martinez, J., O Silva, W., Lesch, A., Nagar, B., Lopes da Silva, Z., . . . Ruzgas, T. (2023). A Rapidly Responsive Sensor for Wireless Detection of Early and Mature Microbial Biofilms.. Angewandte Chemie International Edition, 62(40), Article ID e202308181.
Open this publication in new window or tab >>A Rapidly Responsive Sensor for Wireless Detection of Early and Mature Microbial Biofilms.
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2023 (English)In: Angewandte Chemie International Edition, ISSN 1433-7851, E-ISSN 1521-3773, Vol. 62, no 40, article id e202308181Article in journal (Refereed) Published
Abstract [en]

Biofilm-associated infections, which are able to resist antibiotics, pose a significant challenge in clinical treatments. Such infections have been linked to various medical conditions, including chronic wounds and implant-associated infections, making them a major public-health concern. Early-detection of biofilm formation offers significant advantages in mitigating adverse effects caused by biofilms. In this work, we aim to explore the feasibility of employing a novel wireless sensor for tracking both early-stage and matured-biofilms formed by the medically relevant bacteria Staphylococcus aureus and Pseudomonas aeruginosa. The sensor utilizes electrochemical reduction of an AgCl layer bridging two silver legs made by inkjet-printing, forming a part of near-field-communication tag antenna. The antenna is interfaced with a carbon cloth designed to promote the growth of microorganisms, thereby serving as an electron source for reduction of the resistive AgCl into a highly-conductive Ag bridge. The AgCl-Ag transformation significantly alters the impedance of the antenna, facilitating wireless identification of an endpoint caused by microbial growth. To the best of our knowledge, this study for the first time presents the evidence showcasing that electrons released through the actions of bacteria can be harnessed to convert AgCl to Ag, thus enabling the wireless, battery-less, and chip-less early-detection of biofilm formation.

Place, publisher, year, edition, pages
John Wiley & Sons, 2023
Keywords
Microbial biofilm, chip-less wireless sensing, inkjet printing, mediated electron transfer, near field communication
National Category
Microbiology
Identifiers
urn:nbn:se:mau:diva-62039 (URN)10.1002/anie.202308181 (DOI)001090146000021 ()37490019 (PubMedID)2-s2.0-85168699269 (Scopus ID)
Available from: 2023-08-22 Created: 2023-08-22 Last updated: 2023-12-13Bibliographically approved
Szczepanczyk, M., Paul, L., Ruzgas, T. & Björklund, S. (2023). Comparison of Oxygen Electrode Chronoamperometry and Spectrophotometry for Determination of Catalase Activity. Oxygen, 3(1), 77-89
Open this publication in new window or tab >>Comparison of Oxygen Electrode Chronoamperometry and Spectrophotometry for Determination of Catalase Activity
2023 (English)In: Oxygen, E-ISSN 2673-9801, Vol. 3, no 1, p. 77-89Article in journal (Refereed) Published
Abstract [en]

Catalase is a key antioxidative enzyme, and a deficiency or malfunction of catalase is hypothesized to be related to various diseases. To investigate catalase activity, it is important to use reliable methods and experimental protocols enabling consistent fallouts. One major problem, however, is that the activity values obtained with different techniques and procedures can vary to a large extent. The aim of this work was to identify experimental conditions that provide similar catalase activity values with two different methods based on either spectrophotometry or chronoam- perometry. The investigated parameters include the concentration of catalase and its substrate (H2O2), as well as the effect of deoxygenation of the catalase medium by nitrogen (N2). Within the frame of investigated conditions, we show that spectrophotometry is strongly affected by the catalase concen- tration, whereas chronoamperometry is shown to be more dependent on the substrate concentration. Deoxygenation leads to elevated catalase activity values in the case of chronoamperometry, whereas it shows no influence on the results obtained with spectrophotometry. In particular, in the case of low substrate concentrations (i.e., low catalase reaction rates), higher and more accurate results are obtained with deoxygenation in the case of chronoamperometry measurements due to minimized oxygen escape. The effect of deoxygenation, giving rise to elevated catalase activity values, however, is not statistically significant at high substrate concentrations, implying that the protocol can be sim- plified by excluding this step as long as the other parameters are optimized. Finally, by comparing the two methods at different experimental conditions, we identified protocols resulting in similar results, i.e., 10 mM H2O2 and catalase activity of 4–5 U/mL. Based on this work, improved consistency of catalase activity data obtained with different methodologies and in different labs is expected.

Place, publisher, year, edition, pages
MDPI, 2023
National Category
Chemical Sciences
Identifiers
urn:nbn:se:mau:diva-58452 (URN)10.3390/oxygen3010006 (DOI)
Available from: 2023-03-01 Created: 2023-03-01 Last updated: 2023-09-27Bibliographically approved
Morin, M., Runnsjö, A., Ruzgas, T., Engblom, J. & Björklund, S. (2023). Effects of storage conditions on permeability and electrical impedance properties of the skin barrier.. International Journal of Pharmaceutics, 637, 122891, Article ID 122891.
Open this publication in new window or tab >>Effects of storage conditions on permeability and electrical impedance properties of the skin barrier.
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2023 (English)In: International Journal of Pharmaceutics, ISSN 0378-5173, E-ISSN 1873-3476, Vol. 637, p. 122891-, article id 122891Article in journal (Refereed) Published
Abstract [en]

The aim of this study was to investigate the effect of various skin preservation protocols on in vitro drug permeation, epidermal-dermal drug distribution, and electrical impedance properties of skin membranes. Acyclovir (AC) and methyl salicylate (MS) were selected as model drugs due to their different physicochemical properties and skin metabolic profiles. In particular, AC is relatively hydrophilic (logP -1.8) and not expected to be affected by skin metabolism, while MS is relatively lipophilic (logP 2.5) and susceptible to metabolism, being a substrate for esterase residing in skin. Skin from pig ears was used and freshly excised into split-thickness membranes, which were divided and immediately stored at five different storage conditions: a) 4 °C overnight (fresh control), b) 4 °C for 4 days, c) and d) -20 °C for 6 weeks and one year, respectively, and e) -80 °C for 6 weeks. Based on the combined results, general trends are observed showing that fresh skin is associated with lower permeation of both model drugs and higher skin membrane electrical resistance, as compared to the other storage conditions. Interestingly, in the case of fresh skin, significantly lower amounts of MS are detected in the epidermis and dermis compartments, implying higher levels of ester hydrolysis of MS (i.e., higher esterase activity). In line with this, the concentration of salicylic acid (SA) extracted from the dermis is significantly higher for fresh skin, as compared to the other storage conditions. Nevertheless, for all storage conditions, substantial amounts of SA are detected in the receptor medium, as well as in the epidermis and dermis, implying that esterase activity is maintained to some extent in all cases. For AC, which is not expected to be affected by skin metabolism, freeze storage (protocols c-e) is observed to result in higher accumulation of AC in the epidermis, as compared to the case of fresh skin, while the AC concentration in dermis is unaffected. These observations can be rationalized primarily by the observed lower permeability of fresh skin towards this hydrophilic substance. Finally, a strong correlation between AC permeation and electrical skin resistance is shown for individual skin membranes irrespective of storage condition, while the corresponding correlation for MS is inferior. On the other hand, a strong correlation is shown for individual membranes between MS permeation and electrical skin capacitance, while a similar correlation for AC is lower. The observed correlations between drug permeability and electrical impedance open up for standardizing in vitro data for improved analysis and comparisons between permeability results obtained with skin stored at different conditions.

Place, publisher, year, edition, pages
Elsevier, 2023
National Category
Dermatology and Venereal Diseases
Identifiers
urn:nbn:se:mau:diva-59303 (URN)10.1016/j.ijpharm.2023.122891 (DOI)000970186500001 ()36997077 (PubMedID)2-s2.0-85151485213 (Scopus ID)
Available from: 2023-04-20 Created: 2023-04-20 Last updated: 2023-07-04Bibliographically approved
Riaz, A., Gidvall, S., Prgomet, Z., Hernandez, A. R., Ruzgas, T., Nilsson, E. J., . . . Valetti, S. (2023). Three-Dimensional Oral Mucosal Equivalents as Models for Transmucosal Drug Permeation Studies. Pharmaceutics, 15(5), 1513-1513
Open this publication in new window or tab >>Three-Dimensional Oral Mucosal Equivalents as Models for Transmucosal Drug Permeation Studies
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2023 (English)In: Pharmaceutics, ISSN 1999-4923, E-ISSN 1999-4923, Vol. 15, no 5, p. 1513-1513Article in journal (Refereed) Published
Abstract [en]

Oral transmucosal administration, where drugs are absorbed directly through the non-keratinized, lining mucosa of the mouth, represents a solution to drug delivery with several advantages. Oral mucosal equivalents (OME) developed as 3D in vitro models are of great interest since they express the correct cell differentiation and tissue architecture, simulating the in vivo conditions better than monolayer cultures or animal tissues. The aim of this work was to develop OME to be used as a membrane for drug permeation studies. We developed both full-thickness (i.e., connective plus epithelial tissue) and split-thickness (i.e., only epithelial tissue) OME using non-tumor-derived human keratinocytes OKF6 TERT-2 obtained from the floor of the mouth. All the OME developed here presented similar transepithelial electrical resistance (TEER) values, comparable to the commercial EpiOral™. Using eletriptan hydrobromide as a model drug, we found that the full-thickness OME had similar drug flux to EpiOral™ (28.8 vs. 29.6 µg/cm2/h), suggesting that the model had the same permeation barrier properties. Furthermore, full-thickness OME showed an increase in ceramide content together with a decrease in phospholipids in comparison to the monolayer culture, indicating that lipid differentiation occurred due to the tissue-engineering protocols. The split-thickness mucosal model resulted in 4–5 cell layers with basal cells still undergoing mitosis. The optimum period at the air–liquid interface for this model was twenty-one days; after longer times, signs of apoptosis appeared. Following the 3R principles, we found that the addition of Ca2+, retinoic acid, linoleic acid, epidermal growth factor and bovine pituitary extract was important but not sufficient to fully replace the fetal bovine serum. Finally, the OME models presented here offer a longer shelf-life than the pre-existing models, which paves the way for the further investigation of broader pharmaceutical applications (i.e., long-term drug exposure, effect on the keratinocytes’ differentiation and inflammatory conditions, etc.).

Place, publisher, year, edition, pages
MDPI, 2023
Keywords
oral transmucosal delivery, oral mucosal equivalents, drug permeation, 3R principles, 3D in vitro models
National Category
Pharmaceutical Sciences
Identifiers
urn:nbn:se:mau:diva-61046 (URN)10.3390/pharmaceutics15051513 (DOI)000997495400001 ()37242755 (PubMedID)2-s2.0-85160448981 (Scopus ID)
Funder
The Crafoord Foundation, 20210937Knowledge Foundation, 20190010
Available from: 2023-06-19 Created: 2023-06-19 Last updated: 2023-08-15Bibliographically approved
Shafaat, A., Žalnėravičius, R., Ratautas, D., Dagys, M., Meškys, R., Rutkienė, R., . . . Ruzgas, T. (2022). Glucose-to-Resistor Transduction Integrated into a Radio-Frequency Antenna for Chip-less and Battery-less Wireless Sensing. ACS Sensors , 7(4), 1222-1234
Open this publication in new window or tab >>Glucose-to-Resistor Transduction Integrated into a Radio-Frequency Antenna for Chip-less and Battery-less Wireless Sensing
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2022 (English)In: ACS Sensors , E-ISSN 2379-3694, Vol. 7, no 4, p. 1222-1234Article in journal (Refereed) Published
Abstract [en]

To maximize the potential of 5G infrastructure in healthcare, simple integration of biosensors with wireless tag antennas would be beneficial. This work introduces novel glucose-to-resistor transduction, which enables simple, wireless biosensor design. The biosensor was realized on a near-field communication tag antenna, where a sensing bioanode generated electrical current and electroreduced a nonconducting antenna material into an excellent conductor. For this, a part of the antenna was replaced by a Ag nanoparticle layer oxidized to high-resistance AgCl. The bioanode was based on Au nanoparticle-wired glucose dehydrogenase (GDH). The exposure of the cathode-bioanode to glucose solution resulted in GDH-catalyzed oxidation of glucose at the bioanode with a concomitant reduction of AgCl to highly conducting Ag on the cathode. The AgCl-to-Ag conversion strongly affected the impedance of the antenna circuit, allowing wireless detection of glucose. Mimicking the final application, the proposed wireless biosensor was ultimately evaluated through the measurement of glucose in whole blood, showing good agreement with the values obtained with a commercially available glucometer. This work, for the first time, demonstrates that making a part of the antenna from the AgCl layer allows achieving simple, chip-less, and battery-less wireless sensing of enzyme-catalyzed reduction reaction. 

Place, publisher, year, edition, pages
American Chemical Society (ACS), 2022
Keywords
Internet of Things, wireless detection of glucose, direct electron transfer, glucose dehydrogenase, chip-less wireless sensing
National Category
Analytical Chemistry
Identifiers
urn:nbn:se:mau:diva-51019 (URN)10.1021/acssensors.2c00394 (DOI)000794994500032 ()35392657 (PubMedID)2-s2.0-85128799436 (Scopus ID)
Funder
Swedish Research Council, 2018-04320Knowledge Foundation, 20170058Knowledge Foundation, 20190010
Available from: 2022-04-08 Created: 2022-04-08 Last updated: 2024-02-05Bibliographically approved
Morin, M., Jankovskaja, S., Ruzgas, T., Henricson, J., Anderson, C. D., Brinte, A., . . . Björklund, S. (2022). Hydrogels and Cubic Liquid Crystals for Non-Invasive Sampling of Low-Molecular-Weight Biomarkers-An Explorative In Vivo Study. Pharmaceutics, 14(2), Article ID 313.
Open this publication in new window or tab >>Hydrogels and Cubic Liquid Crystals for Non-Invasive Sampling of Low-Molecular-Weight Biomarkers-An Explorative In Vivo Study
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2022 (English)In: Pharmaceutics, ISSN 1999-4923, E-ISSN 1999-4923, Vol. 14, no 2, article id 313Article in journal (Refereed) Published
Abstract [en]

The molecular composition of human skin is altered due to diseases, which can be utilized for non-invasive sampling of biomarkers and disease diagnostics. For this to succeed, it is crucial to identify a sampling formulation with high extraction efficiency and reproducibility. Highly hydrated skin is expected to be optimal for increased diffusion of low-molecular-weight biomarkers, enabling efficient extraction as well as enhanced reproducibility as full hydration represents a well-defined endpoint. Here, the aim was to explore water-based formulations with high water activities, ensuring satisfactory skin hydration, for non-invasive sampling of four analytes that may serve as potential biomarkers, namely tryptophan, tyrosine, phenylalanine, and kynurenine. The included formulations consisted of two hydrogels (chitosan and agarose) and two different liquid crystalline cubic phases based on the polar lipid glycerol monooleate, which were all topically applied for 2 h on 35 healthy subjects in vivo. The skin status of all sampling sites was assessed by electrical impedance spectroscopy and transepidermal water loss, enabling explorative correlations between biophysical properties and analyte abundancies. Taken together, all formulations resulted in the successful and reproducible collection of the investigated biomarkers. Still, the cubic phases had an extraction capacity that was approximately two times higher compared to the hydrogels.

Place, publisher, year, edition, pages
MDPI, 2022
Keywords
low-molecular-weight biomarker, tryptophan, kynurenine, tyrosine, phenylalanine, tryptophan-to-kynurenine ratio, skin barrier integrity, stratum corneum, natural moisturizing factor, electrical impedance spectroscopy, transepidermal water loss
National Category
Cancer and Oncology
Identifiers
urn:nbn:se:mau:diva-50952 (URN)10.3390/pharmaceutics14020313 (DOI)000765124800001 ()35214046 (PubMedID)2-s2.0-85124460011 (Scopus ID)
Available from: 2022-04-06 Created: 2022-04-06 Last updated: 2024-02-05Bibliographically approved
Jankovskaja, S., Morin, M., Gustafsson, A., Anderson, C. D., Lehoczki, B., Engblom, J., . . . Ruzgas, T. (2022). Non-Invasive, Topical Sampling of Potential, Low-Molecular Weight, Skin Cancer Biomarkers: A Study on Healthy Volunteers.. Analytical Chemistry, 94(15), 5856-5865
Open this publication in new window or tab >>Non-Invasive, Topical Sampling of Potential, Low-Molecular Weight, Skin Cancer Biomarkers: A Study on Healthy Volunteers.
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2022 (English)In: Analytical Chemistry, ISSN 0003-2700, E-ISSN 1520-6882, Vol. 94, no 15, p. 5856-5865Article in journal (Refereed) Published
Abstract [en]

Monitoring of low-molecular weight cancer biomarkers, such as tryptophan (Trp) and its derivative kynurenine (Kyn), might be advantageous to non-invasive skin cancer detection. Thus, we assessed several approaches of topical sampling of Trp and Kyn, in relation to phenylalanine (Phe) and tyrosine (Tyr), on the volar forearm of six healthy volunteers. The sampling was performed with three hydrogels (made of agarose or/and chitosan), hydrated starch films, cotton swabs, and tape stripping. The biomarkers were successfully sampled by all approaches, but the amount of collected Kyn was low, 20 ± 10 pmol/cm2. Kyn quantification was below LOQ, and thus, it was detected only in 20% of topical samples. To mitigate variability problems of absolute amounts of sampled amino acids, Tyr/Trp, Phe/Trp, and Phe/Tyr ratios were assessed, proving reduced inter-individual variation from 79 to 45% and intra-individual variation from 42 to 21%. Strong positive correlation was found between Phe and Trp, pointing to the Phe/Trp ratio (being in the 1.0–2.0 range, at 95% confidence) being least dependent on sampling materials, approaches, and sweating. This study leads to conclusion that due to the difficulty in quantifying less abundant Kyn, and thus the Trp/Kyn ratio, the Phe/Trp ratio might be a possible, alternative biomarker for detecting skin cancers.

Place, publisher, year, edition, pages
American Chemical Society (ACS), 2022
National Category
Cancer and Oncology
Identifiers
urn:nbn:se:mau:diva-51301 (URN)10.1021/acs.analchem.1c05470 (DOI)000792814500018 ()35394278 (PubMedID)2-s2.0-85128387453 (Scopus ID)
Available from: 2022-05-04 Created: 2022-05-04 Last updated: 2023-11-29Bibliographically approved
Kumlien, C., Acosta, S., Björklund, S., Lavant, E., Lazer, V., Engblom, J., . . . Gershater, M. (2022). Research priorities to prevent and treat diabetic foot ulcers-A digital James Lind Alliance Priority Setting Partnership. Diabetic Medicine, 39(11), Article ID e14947.
Open this publication in new window or tab >>Research priorities to prevent and treat diabetic foot ulcers-A digital James Lind Alliance Priority Setting Partnership
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2022 (English)In: Diabetic Medicine, ISSN 0742-3071, E-ISSN 1464-5491, Vol. 39, no 11, article id e14947Article in journal (Refereed) Published
Abstract [en]

Aim To establish outcomes of a priority setting partnership between participants with diabetes mellitus and clinicians to identify the top 10 research priorities for preventing and treating diabetic foot ulcers (DFUs). Methods Due to the COVID-19 pandemic, the James Lind Alliance Priority Setting Partnership process was adapted into a digital format which involved a pilot survey to identify understandable uncertainties with high relevance for participants tested by calculating the content validity index; a main survey answered by 53 participants living with diabetes and 49 clinicians; and a final digital workshop to process and prioritise the final top 10 research priorities. Results The content validity index was satisfactory for 20 out of 25 uncertainties followed by minor changes and one additional uncertainty. After we processed the 26 uncertainties from the main survey and seven current guidelines, a list of 28 research uncertainties remained for review and discussion in the digital workshop. The final top 10 research priorities included the organisation of diabetes care; screening of diabetes, impaired blood circulation, neuropathy, and skin properties; vascular surgical treatment; importance of self-care; help from significant others; pressure relief; and prevention of infection. Conclusion The top 10 research priorities for preventing and treating DFUs represent consensus areas from persons living with diabetes and clinicians to guide future research. These research priorities can justify and inform strategic allocation of research funding. The digitalisation of James Lind Alliance methodology was feasible.

Place, publisher, year, edition, pages
John Wiley & Sons, 2022
Keywords
diabetic foot ulcer, digital platform, James Lind Alliance, prevention, priority setting partnership
National Category
Endocrinology and Diabetes
Identifiers
urn:nbn:se:mau:diva-55061 (URN)10.1111/dme.14947 (DOI)000852819200001 ()36054410 (PubMedID)2-s2.0-85137434899 (Scopus ID)
Available from: 2022-09-22 Created: 2022-09-22 Last updated: 2024-02-05Bibliographically approved
Morin, M., Björklund, S., Jankovskaja, S., Moore, K., Delgado-Charro, M. B., Ruzgas, T., . . . Engblom, J. (2022). Reverse Iontophoretic Extraction of Skin Cancer-Related Biomarkers. Pharmaceutics, 14(1), Article ID 79.
Open this publication in new window or tab >>Reverse Iontophoretic Extraction of Skin Cancer-Related Biomarkers
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2022 (English)In: Pharmaceutics, ISSN 1999-4923, E-ISSN 1999-4923, Vol. 14, no 1, article id 79Article in journal (Refereed) Published
Abstract [en]

Non-invasive methods for early diagnosis of skin cancer are highly valued. One possible approach is to monitor relevant biomarkers such as tryptophan (Trp) and kynurenine (Kyn), on the skin surface. The primary aim of this in vitro investigation was, therefore, to examine whether reverse iontophoresis (RI) can enhance the extraction of Trp and Kyn, and to demonstrate how the Trp/Kyn ratio acquired from the skin surface reflects that in the epidermal tissue. The study also explored whether the pH of the receiver medium impacted on extraction efficiency, and assessed the suitability of a bicontinuous cubic liquid crystal as an alternative to a simple buffer solution for this purpose. RI substantially enhanced the extraction of Trp and Kyn, in particular towards the cathode. The Trp/Kyn ratio obtained on the surface matched that in the viable skin. Increasing the receiver solution pH from 4 to 9 improved extraction of both analytes, but did not significantly change the Trp/Kyn ratio. RI extraction of Trp and Kyn into the cubic liquid crystal was comparable to that achieved with simple aqueous receiver solutions. We conclude that RI offers a potential for non-invasive sampling of low-molecular weight biomarkers and further investigations in vivo are therefore warranted.

Place, publisher, year, edition, pages
MDPI, 2022
Keywords
tryptophan, kynurenine, tryptophan-to-kynurenine ratio, cancer-related biomarkers, non-invasive extraction, bicontinuous cubic liquid crystals
National Category
Pharmaceutical Chemistry
Identifiers
urn:nbn:se:mau:diva-50524 (URN)10.3390/pharmaceutics14010079 (DOI)000758502900001 ()35056976 (PubMedID)2-s2.0-85122161916 (Scopus ID)
Available from: 2022-03-09 Created: 2022-03-09 Last updated: 2024-02-05Bibliographically approved
Projects
Pickering emulsions on skin: Effects of ethanol prior to, during and after application at different ambient conditions; Malmö UniversityNano and micro scale characterization of coatings in relation to their functional properties; Malmö UniversityDetection of tumor biomarkers based on MIP-antibody proximity ligation assays and fluorescent synthetic nanoprobes; Malmö University, Faculty of Health and Society (HS), Department of Biomedical Science (BMV)Non-invasive monitoring of skin disorders progression and healing – a low molecular weight biomarker approach; Malmö UniversityLipidnanopartikel – proteininteraktioner: Formuleringsoptimering för bättre terapeutisk effekt; Malmö University, Biofilms Research Center for BiointerfacesWireless biosensors based on oxidation and reduction of nanoparticlesWound healing: Importance of endogenous LMW compounds for skin recovery and their use as biomarkers for diagnostic purpose; Malmö UniversityLow-cost wireless sensors for early detection of wound infection; Malmö University, Biofilms Research Center for BiointerfacesBiomimetic surfaces and sensors for detection and inhibition of Covid-19 virus and antibodies; Malmö University
Organisations
Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0003-0304-7528

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