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Plant Disease Dec 2023Ginger (Zingiber officinale) is an important commercial crop that has been widely cultivated in China for more than 2500 years. One variety, Tongling white ginger, has...
Ginger (Zingiber officinale) is an important commercial crop that has been widely cultivated in China for more than 2500 years. One variety, Tongling white ginger, has been grown in the Yi'an District of Tongling city, Anhui province (30°45 N, 117°43 E), China. In August 2022, symptoms of yellowing and wilting were observed on ginger plants, with a disease incidence rate exceeding 20% in the field. The stem base of the diseased plants became soft, brown and water-soaked. Additionally, the rhizomes displayed symptoms of browning and water-soaked rot, resembling those caused by Ralstonia solanacearum and Enterobacter cloacae (Yu et al. 2003; Nishijima et al. 2004; Liu et al. 2021). Consequently, ginger bacterial wilt disease may potentially emerge from a combination of infections by diverse pathogenic bacteria. To identify novel pathogens causing the wilt disease, stem tissues of the diseased plants from different locations were sterilized with 1% sodium hypochlorite (NaOCl) for 10 min, followed by at least three time rinses with sterile water. The sterilized samples were then ground with 0.9% saline solution and left at room temperature for 30 min. A 20 μL aliquot of the suspension was serially diluted and cultured on Luria-Bertani (LB) medium at 28°C. A total of 217 isolates was picked and purified for taxonomic identification by 16S rRNA gene analyses with the primer 27F/1492R (Weisburg et al. 1991). Among these isolates, 23 single colony isolates were identified as A. xylosoxidans through NCBI BLASTn analyses. Furthermore, three single isolates from different locations were randomly selected for further experiments. The growing colonies appeared opaque white and round. Microscopic evaluation revealed that cells were rod-shaped with an average length of 1.95 µm and average width of 0.46 µm. The three isolates shared identical 16S rRNA sequences, displayed 99.72% identity with the sequence from A. xylosoxidans strain SeqID2 (GenBank accession NO. MH266081.1). The glutamate synthase (gltB), GTP-binding membrane protein (lepA), NADH:ubiquinone oxidoreductase subunit L (nuoL), RNA polymerase beta-subunit (rpoB), and the enolase (eno) genes of the three isolates were amplified by PCR using primer pairs gltB-F/gltB-R, lepA-F/lepA-R, nuoL-F/nuoL-R, rpoB-F/rpoB-R and eno-F/eno-R, respectively (Spilker et al. 2012; Vandamme et al. 2016). The gene sequences of 16S rRNA (OQ711945, OQ740153 and OR230037), gltB (OR242732, OQ737692 and OR262112), lepA (OR233727, OQ737693 and OR262113), nuoL (OR233726, OQ737694 and OR262114), ropB (OR233725, OQ737695 and OR262115) and eno (OR242733, OQ737696 and OR262116) for the isolates ZOR02, ZOR05 and ZOR12 were deposited in GenBank database. The gltB, lepA, nuoL, rpoB and eno sequences of the isolates ZOR02, ZOR05 and ZOR12 showed 98.66-99.16%, 98.9-100%, 96.28%-97.34%, 98.47-99.44% and 99.27-99.82% similarity to A. xylosoxidans strain AX27, respectively. Phylogenetic trees were constructed based on the 16S rRNA and gltB-lepA-nuoL-rpoB-eno multilocus using the Neighbor-Joining (NJ) method with 1000 bootstrap replicates in MEGA11.0 software (Álvarez et al. 2018). For pathogenicity tests, bacterial suspensions were initially prepared in sterile water at a final concentration of 108 CFU mL-1. Subsequently, 10 μL of bacterial suspensions was injected into the stem base of two-month-old ginger plants, while sterile water was used as a control (Wang et al. 2022). These plants were then incubated at 28°C and 70% relative humidity. There were three replicates for each treatment, and each replicate contained five plants. After six days of inoculation, the ginger plants injected with bacterial suspensions alone exhibited severe wilting symptoms similar to those observed in the field. However, water-soaked symptoms were not observed on rhizome tissues from the pathogen-infected plants. Bacterial pathogens were re-isolated from the diseased plants and identified using the morphological and molecular methods to meet Koch's hypothetical tests. To our knowledge, this is the first report of A. xylosoxidans causing wilt disease of ginger in China. In 2022, the average yield loss due to wilt disease in the Yi'an District of Tongling exceeded 20%, posing a major threat to local ginger cultivation. Effective disease management strategies are needed to develop for the control and prevention of the disease.
PubMed: 38100672
DOI: 10.1094/PDIS-05-23-0891-PDN -
Annals of Laboratory Medicine Sep 2023Sterility and safety assurance of hematopoietic stem cell (HSC) products is critical in transplantation. Microbial contamination can lead to product disposal and...
BACKGROUND
Sterility and safety assurance of hematopoietic stem cell (HSC) products is critical in transplantation. Microbial contamination can lead to product disposal and increases the risk of unsuccessful clinical outcomes. Therefore, it is important to implement and maintain good practice guidelines and regulations for the HSC collection and processing unit in each hospital. We aimed to share our experiences and suggest strategies to improve the quality assurance of HSC processing.
METHODS
We retrospectively analyzed microbial culture results of 11,743 HSC products processed over a 25-year period (January 1996 to May 2021). Because of reorganization of the HSC management system in 2008, the 25-year period was divided into periods 1 (January 1996 to December 2007) and 2 (January 2008 to May 2021). We reviewed all culture results of the HSC products and stored aliquot samples and collected culture results for peripheral blood and catheter samples.
RESULTS
Of the 11,743 products in total, 35 (0.3%) were contaminated by microorganisms, including 19 (0.5%) of 3,861 products during period 1 and 16 (0.2%) of 7,882 products during period 2. was the most commonly identified microorganism (15.8%) during period 1 and coagulase-negative was the most commonly identified (31.3%) during period 2. HSC product contamination occurred most often during HSC collection and processing.
CONCLUSIONS
The contamination rate decreased significantly during period 2, when the HSC management system was reorganized. Our results imply that handling HSC products by trained personnel and adopting established protocols, including quality assurance programs, aid in decreasing the contamination risk.
Topics: Humans; Hematopoietic Stem Cell Transplantation; Hematopoietic Stem Cells; Retrospective Studies; Quality Improvement; Staphylococcus
PubMed: 37080749
DOI: 10.3343/alm.2023.43.5.477 -
Plant Disease Jul 2023Wasabi (Eutrema japonicum) is a root vegetable that is cultivated at large scales in southwestern China. In November 2021, approximately 40% of plants in a forested...
Wasabi (Eutrema japonicum) is a root vegetable that is cultivated at large scales in southwestern China. In November 2021, approximately 40% of plants in a forested plantation in Dadishui, Yunnan Province, China (25.47°N, 103.22°E), showed leaf spot symptoms. The early symptoms were small black spots that gradually expanded into irregular brown to black lesions (0.5-1.5 cm), which were restricted by leaf veins. Yellow halos were observed at the outer edges of necrotic lesions. To identify the causal agent, we collected 20 diseased leaves and obtained fungal isolates from symptomatic leaf tissues. Following surface sterilization with 75% ethanol for 30 s, the tissues were cultured on potato dextrose agar (PDA) plates and incubated at 25°C under a 12 h light/12 h dark light cycle. After 7 days of incubation, a total of 12 isolates were obtained through single-spore culture. All isolates had similar colony morphology, and produced fluffy white mycelia and yellow pigment after 1 week of PDA culture at 25°C, and blackish- brown mycelium, tan pigment, and conidia after 2 weeks. The conidia were hyaline and cylindrical, with an average size of 4.6 μm × 2.2 μm. These morphological characteristics similar to the description of Leptosphaeria biglobosa (Shoemaker et. al, 2001) and Leptosphaeria maculans (Vincenot et al. 2008). Genomic DNA was extracted from mycelium of isolate SK-1, which was harvested from 10-day-old PDA culture using a FAST plant genomic DNA Extraction Kit (Biomed, China), following the manufacturer's instructions. The species-specific primers LbigF, LmacF, and LmacR (Liu et al. 2006) were used for identification via polymerase chain reaction (PCR). A 444-bp fragment characteristic of L. biglobosa 'brassicae' (Lbb), and a 330-bp of L. maculans 'brassicae' (Lmb) were amplified, respectively. Internal transcribed spacer (ITS) sequences (592 bp), part of the 5' end of beta-tubulin (968 bp), and actin (899 bp) were also amplified using the primers ITS1/ITS4, BT1/BT2, and ACTF/ACTR (Vincenot et al. 2008), respectively. PCR was performed in a volume of 25 μL containing 12.5 μL 2 × T5 Super PCR Mix (Tsingke Biotech, Beijing, China), 1 μL 10 μM primer (Tsingke Biotech), 1 μL DNA template, and an aliquot of sterile water to attain the total volume. The thermal cycler settings were 5 min at 98°C; 35 cycles of 10 s at 98°C, 10 s at 58°C, and 30 s at 72°C; and extension for 2 min at 72°C. The ITS sequence of isolate SK-1 (GenBank accession no. OQ216838), the partial β-tubulin gene sequence (OQ241183), and the actin gene sequence (OQ241184) indicated 100% query cover and 100% identity with L. biglobosa (DQ458906), Lbb strain B3.6 (AY748995), and Lbb strain 2379-4 (AY748949), respectively. Phylogenetic analysis (King et al. 2022) also identified of isolate SK-1 as Lbb. To determinate its pathogenicity, isolate SK-1 was grown on PDA incubated at 28°C for 2 weeks, and conidial suspensions were prepared at a concentration of 106 conidia/mL. Then, 15 leaves of 4-month-old E. japonicum seedlings were needle-wounded on the front and inoculated by syringe injection of 10 μL of the appropriate conidial suspension. We used 10 μL of the sterilized distilled water as the control under forest growth conditions. All inoculation sites were covered with cotton strips and moistened with 1.0 mL sterile water to maintain humidity. After 12 days of incubation, the leaves developed symptoms similar to those observed in the field, and the fungus was reisolated from diseased leaves, whereas the controls remained healthy. Based on these results, we identified L. biglobosa 'brassicae' as the causal agent of leaf spot on E. japonicum in China. This fungus has been reported to cause blackleg in many Brassica crops in China such as Brassica napus (Fitt et al. 2006), Brassica oleracea (Zhou et al. 2019), B. juncea var. tumida (Deng et al. 2020), Brassica rapa subsp. pekinensis (Yu et al. 2021). To the best of our knowledge, this is the first report of L. biglobosa causing leaf spots in E. japonicum in China. Our data provide a basis for disease management in E. japonicum production in China.
PubMed: 37498637
DOI: 10.1094/PDIS-06-23-1182-PDN -
The International Journal of... Aug 2023Tertiary level hospital in Lusaka, Zambia. To measure concordance between Xpert MTB/RIF Ultra (Ultra) results of stool with and without transport media, and compare...
Tertiary level hospital in Lusaka, Zambia. To measure concordance between Xpert MTB/RIF Ultra (Ultra) results of stool with and without transport media, and compare Ultra results from the two stool processing methods to Ultra and culture results using gastric aspirates (GA). This was a cross-sectional study collecting stool and GA from children 0-5 years presenting with signs and symptoms of TB. Stool was processed for Ultra testing by two methods: the Simple-One-Step (SOS) on an aliquot of stool and PrimeStore MTM Molecular Transport Medium (PS-MTM) using a stool swab. A total of 114 children (median age: 17 months, IQR 7-30) provided both a stool and a GA sample. Stool Ultra results processed using the PS-MTM method showed high concordance with stool Ultra results processed by the SOS method, with only 1/114 discordant results. Concordance with GA Ultra was high as well, as 9/13 (MTB) cases detected were identified by all three methods. Ultra results from stool swabs collected using PS-MTM were equivalent to results from stool using the SOS method and GA. Given that PS-MTM inactivates MTB and stabilises DNA without cold chain, using it for stool has the potential to increase access to a TB diagnosis for children in underserved areas.
Topics: Humans; Child; Infant; Tuberculosis, Pulmonary; Cross-Sectional Studies; Sensitivity and Specificity; Zambia; Sputum; Mycobacterium tuberculosis
PubMed: 37491746
DOI: 10.5588/ijtld.22.0530 -
BMJ Open Jun 2024Postoperative complications increase mortality, disability and costs. Advanced understanding of the risk factors for postoperative complications is needed to improve...
PURPOSE
Postoperative complications increase mortality, disability and costs. Advanced understanding of the risk factors for postoperative complications is needed to improve surgical outcomes. This paper discusses the rationale and profile of the BIGPROMISE (biomarkers to guide perioperative management and improve outcome in high-risk surgery) cohort, that aims to investigate risk factors, pathophysiology and outcomes related to postoperative complications.
PARTICIPANTS
Adult patients undergoing major surgery in two tertiary teaching hospitals. Clinical data and blood samples are collected before surgery, at the end of surgery and on the first, second and third postoperative day. At each time point a panel of cardiovascular, inflammatory, renal, haematological and metabolic biomarkers is assessed. Aliquots of plasma, serum and whole blood of each time point are frozen and stored. Data on severe complications are prospectively collected during 30 days after surgery. Functional status is assessed before surgery and after 120 days using the WHO Disability Assessment Schedule (WHODAS) 2.0. Mortality is followed up until 2 years after surgery.
FINDINGS TO DATE
The first patient was enrolled on 8 October 2021. Currently (1 January 2024) 3086 patients were screened for eligibility, of whom 1750 (57%) provided informed consent for study participation. Median age was 66 years (60; 73), 28% were female, and 68% of all patients were American Society of Anaesthesiologists (ASA) physical status class 3. Most common types of major surgery were cardiac (49%) and gastro-intestinal procedures (26%). The overall incidence of 30-day severe postoperative complications was 16%.
FUTURE PLANS
By the end of the recruitment phase, expected in 2026, approximately 3000 patients with major surgery will have been enrolled. This cohort allows us to investigate the role of pathophysiological perioperative processes in the cause of postoperative complications, and to discover and develop new biomarkers to improve risk stratification for adverse postoperative outcomes.
TRIAL REGISTRATION NUMBER
NCT05199025.
Topics: Humans; Female; Male; Postoperative Complications; Aged; Middle Aged; Biomarkers; Risk Factors; Biological Specimen Banks; Prospective Studies; Surgical Procedures, Operative
PubMed: 38862228
DOI: 10.1136/bmjopen-2023-078307 -
Frontiers in Microbiology 2024Acute febrile illnesses (AFI) in developing tropical and sub-tropical nations are challenging to diagnose due to the numerous causes and non-specific symptoms. The...
INTRODUCTION
Acute febrile illnesses (AFI) in developing tropical and sub-tropical nations are challenging to diagnose due to the numerous causes and non-specific symptoms. The proliferation of rapid diagnostic testing and successful control campaigns against malaria have revealed that non- pathogens still contribute significantly to AFI burden. Thus, a more complete understanding of local trends and potential causes is important for selecting the correct treatment course, which in turn will reduce morbidity and mortality. Next-generation sequencing (NGS) in a laboratory setting can be used to identify known and novel pathogens in individuals with AFI.
METHODS
In this study, plasma was collected from 228 febrile patients tested negative for malaria at clinics across Senegal from 2020-2022. Total nucleic acids were extracted and converted to metagenomic NGS libraries. To identify viral pathogens, especially those present at low concentration, an aliquot of each library was processed with a viral enrichment panel and sequenced. Corresponding metagenomic libraries were also sequenced to identify non-viral pathogens.
RESULTS AND DISCUSSION
Sequencing reads for pathogens with a possible link to febrile illness were identified in 51/228 specimens, including (but not limited to): (N = 7), West Nile virus (N = 3), (N = 2), (N = 1), human herpesvirus 8 (N = 1), and Saffold virus (N = 1). Reads corresponding to were detected in 19 specimens, though their presence in the cohort was likely due to user error of rapid diagnostic testing or incorrect specimen segregation at the clinics. Mosquito-borne pathogens were typically detected just after the conclusion of the rainy season, while tick-borne pathogens were mostly detected before the rainy season. The three West Nile virus strains were phylogenetically characterized and shown to be related to both European and North American clades. Surveys such as this will increase the understanding of the potential causes of non-malarial AFI, which may help inform diagnostic and treatment options for clinicians who provide care to patients in Senegal.
PubMed: 38655084
DOI: 10.3389/fmicb.2024.1362714 -
PloS One 2024Fresh-frozen stool banks intended for humans with gastrointestinal and metabolic disorders have been recently established and there are ongoing efforts to establish the...
Fresh-frozen stool banks intended for humans with gastrointestinal and metabolic disorders have been recently established and there are ongoing efforts to establish the first veterinary fresh-frozen stool bank. Fresh frozen stored feces provide an advantage of increased availability and accessibility to high-quality optimal donor fecal material. The stability of frozen canine feces regarding fecal microbiome composition and diversity has not been reported in dogs, providing the basis for this study. We hypothesized that fecal microbial composition and diversity of healthy dogs would remain stable when stored at -20°C and -80°C for up to 12 months compared to baseline samples evaluated before freezing. Stool samples were collected from 20 apparently healthy dogs, manually homogenized, cryopreserved in 20% glycerol and aliquoted, frozen in liquid nitrogen and stored at -20°C or -80°C for 3, 6, 9, and 12 months. At baseline and after period of storage, aliquots were thawed and treated with propidium monoazide before fecal DNA extraction. Following long-read 16S-rRNA amplicon sequencing, bacterial community composition and diversity were compared among treatment groups. We demonstrated that fresh-frozen canine stools collected from 20 apparently healthy dogs could be stored for up to 12 months at -80°C with minimal change in microbial community composition and diversity and that storage at -80°C is superior to storage at -20°C. We also found that differences between dogs had the largest effect on community composition and diversity. Relative abundances of certain bacterial taxa, including those known to be short-chain fatty acid producers, varied significantly with specific storage temperatures and duration. Further work is required to ascertain whether fecal donor material that differs in bacterial community composition and diversity across storage conditions and duration could lead to differences in clinical efficacy for specific clinical indications of fecal microbiota transplantation.
Topics: Humans; Dogs; Animals; Specimen Handling; Feces; Microbiota; Cryopreservation; Gastrointestinal Tract; Bacteria; RNA, Ribosomal, 16S
PubMed: 38324560
DOI: 10.1371/journal.pone.0294730 -
Plant Disease Nov 2023Ceylon ironwood (Mesua ferrea Linn.) or Penaga lilin is one of Asia's most popular tropical herbal plants, including Malaysia (Sharma et al., 2017). The trees are...
Ceylon ironwood (Mesua ferrea Linn.) or Penaga lilin is one of Asia's most popular tropical herbal plants, including Malaysia (Sharma et al., 2017). The trees are cultivated for their aesthetic value and pharmacological properties, especially as traditional remedies for asthma, dermatopathy, inflammation, and rheumatic conditions (Adib et al., 2019). In August 2022, a disease survey was conducted on Ceylon ironwood trees ranging from 5 to 12 years old in Botanical Park, Putrajaya, Malaysia, with 80% exhibiting shoot dieback disease of the 15 trees exhibiting shoot dieback disease. Symptoms include irregular, water-soaked with brown lesions on young leaves and shoots, where the small lesion coalesced and formed broad necrotic regions, subsequently causing dieback and gradual defoliation. Three infected shoots were collected from each tree, excised into small pieces (10 to 20 mm), immersed with 75% ethanol for 3 min, washed with 2% NaOCl solution for 1 min, and rinsed twice for 1 min in sterilized distilled water. A 10 µl aliquot of the sample suspension was streaked onto nutrient agar (NA) and incubated for 24 h to 48 h at 35 °C. A total of 15 isolates with similar morphology were obtained, and each isolate was re-streaked three times to obtain pure colonies that were round, smooth, with irregular edges, and produced yellow pigment in culture. All isolates were Gram-negative, negative for indole production, and utilized glucose, maltose, trehalose, sucrose, D-lactose, and pectin. Three representative isolates (C001, C002, and C003) with similar morphology were selected for further characterization. The total genomic DNA of all isolates was extracted from overnight cultures using Geneaid™ DNA Isolation Kit (Geneaid Biotech Ltd., Taiwan). PCR amplification of 16S rDNA (Zhou et al., 2015) and species-specific infB (Brady et al., 2008) genes was performed, and each of the ~1500 bp and ~900 bp amplicons were sequenced. BLASTn and phylogenetic analyses revealed all isolates were 100% identical to Pantoea anthophila (P. anthophila) LGM 2558 strains (Accession Nos. NR_116749 and NR_116113) for the 16S rDNA gene. They were 99% identical to P. anthophila CL1 strain (Accession Number CP110473) for infB gene. These sequences were later deposited in the GenBank (Accession Nos. OQ772233, OQ772234, and OQ772235 for 16S rDNA gene, and OQ803527, OQ803528, and OQ803529 for infB gene). For the pathogenicity test, healthy Ceylon ironwood seedlings' shoots were inoculated with 10 mL of each isolate suspension (1 x 108 CFU/ml) by spraying the inoculum on the young shoots using a sterilized spray bottle. Control seedlings were inoculated with sterile water. The inoculated shoots were covered with a sealed plastic bag to maintain the moisture and were kept in the greenhouse with temperatures ranging from 26 to 35 °C. The experiments were repeated twice, with three replicates for each treatment. Inoculated shoots showed dieback symptoms like natural infection, including irregular, water-soaked, and brown lesions on leaves and young shoots at 10 days post-inoculation. Control seedlings remained asymptomatic. The pathogen was re-isolated and identified via sequencing of the 16S rDNA and infB genes, thus fulfilling Koch's postulates. Previously, P. anthophila has been reported to cause soft rot in wampee plants in China (Zhou et al., 2015) and leaf blight of cotton in Pakistan (Tufail et al., 2020). To our knowledge, this is the first report of P. anthophila causing shoot dieback disease of Ceylon ironwood trees in Malaysia. Plant disease management strategies need to be established to reduce losses due to P. anthophila infection since the pathogen could limit Ceylon ironwood tree production in Malaysia.
PubMed: 37938907
DOI: 10.1094/PDIS-07-23-1278-PDN -
Spinal Cord Mar 2024To describe the concept, establishment and the operationalization of the biobank of the Swiss Spinal Cord Injury Cohort Study (SwiSCI), the available biosamples, and...
OBJECTIVES
To describe the concept, establishment and the operationalization of the biobank of the Swiss Spinal Cord Injury Cohort Study (SwiSCI), the available biosamples, and demographic and clinical characteristics of study participants.
SETTING
The SwiSCI biobank is a platform for research within SwiSCI. It collects and processes serum, plasma, PBMCs, RNA, DNA, and urine from three rehabilitation centers. Samples are collected at admission to first rehabilitation and at discharge. Additionly, the biobank provides services to projects nested in SwiSCI or otherclinical trials among Spinal Cord Injury population.
METHODS
Descriptive statistics were used for an overview of available biosamples, study participant characteristics, and comparison of the participating centers.
RESULTS
Between the SwiSCI biobank establishment on June 27th, 2016, and October 19th, 2023, the SwiSCI Study has obtained informed consent from 524 individuals. Of these, 315 (60.1%) have agreed to donate biospecimens to the biobank. The average age of the contributors was 54 years (range: 38-65), with the majority being male (80%). Most participants suffered from traumatic injuries (66%) and were classified as paraplegic (64%). Approximately 80% presented with motor and sensory-incomplete SCI. The median Spinal Cord Independence Measure (SCIM) score was 31 (Interquartile Range: 19-58). The proportion of individuals providing paired biosamples at two distinct time points ranged from 63% (for RNA) to 65% (for urine and urine sediment).
CONCLUSIONS
The SwiSCI biobank is a unique platform designed to serve as a basis for collaborative SCI research, including multi-omics approaches. The longitudinal collection of biospecimens and cryopreservation of multiple aliquots for each participant are fundamental for scrutinizing the temporal associations, ensuring research reproducibility, and achieving an adequate sample size for future investigations.
Topics: Humans; Male; Adult; Middle Aged; Aged; Female; Spinal Cord Injuries; Cohort Studies; Switzerland; Reproducibility of Results; Biological Specimen Banks; RNA
PubMed: 38287141
DOI: 10.1038/s41393-024-00958-x -
Nanomaterials (Basel, Switzerland) Aug 2023A novel voltammetric sensor based on a self-assembled composite formed by native DNA and electropolymerized N-phenyl-3-(phenylimino)-3H-phenothiazin-7-amine has been...
A novel voltammetric sensor based on a self-assembled composite formed by native DNA and electropolymerized N-phenyl-3-(phenylimino)-3H-phenothiazin-7-amine has been developed and applied for sensitive determination of doxorubicin, an anthracycline drug applied for cancer therapy. For this purpose, a monomeric phenothiazine derivative has been deposited on the glassy carbon electrode from the 0.4 M HSO-acetone mixture (1:1 /) by multiple potential cycling. The DNA aliquot was either on the electrode modified with electropolymerized film or added to the reaction medium prior to electropolymerization. The DNA entrapment and its influence on the redox behavior of the underlying layer were studied by scanning electron microscopy and electrochemical impedance spectroscopy. The DNA-doxorubicin interactions affected the charge distribution in the surface layer and, hence, altered the redox equilibrium of the polyphenothiazine coating. The voltametric signal was successfully applied for the determination of doxorubicin in the concentration range from 10 pM to 0.2 mM (limit of detection 5 pM). The DNA sensor was tested on spiked artificial plasma samples and two commercial medications (recovery of 90-95%). After further testing on real clinical samples, the electrochemical DNA sensor developed can find application in monitoring drug release and screening new antitumor drugs able to intercalate DNA.
PubMed: 37630955
DOI: 10.3390/nano13162369