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1.
JAMA Netw Open ; 7(4): e246565, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38619840

RESUMO

Importance: Timely tests are warranted to assess the association between generative artificial intelligence (GenAI) use and physicians' work efforts. Objective: To investigate the association between GenAI-drafted replies for patient messages and physician time spent on answering messages and the length of replies. Design, Setting, and Participants: Randomized waiting list quality improvement (QI) study from June to August 2023 in an academic health system. Primary care physicians were randomized to an immediate activation group and a delayed activation group. Data were analyzed from August to November 2023. Exposure: Access to GenAI-drafted replies for patient messages. Main Outcomes and Measures: Time spent (1) reading messages, (2) replying to messages, (3) length of replies, and (4) physician likelihood to recommend GenAI drafts. The a priori hypothesis was that GenAI drafts would be associated with less physician time spent reading and replying to messages. A mixed-effects model was used. Results: Fifty-two physicians participated in this QI study, with 25 randomized to the immediate activation group and 27 randomized to the delayed activation group. A contemporary control group included 70 physicians. There were 18 female participants (72.0%) in the immediate group and 17 female participants (63.0%) in the delayed group; the median age range was 35-44 years in the immediate group and 45-54 years in the delayed group. The median (IQR) time spent reading messages in the immediate group was 26 (11-69) seconds at baseline, 31 (15-70) seconds 3 weeks after entry to the intervention, and 31 (14-70) seconds 6 weeks after entry. The delayed group's median (IQR) read time was 25 (10-67) seconds at baseline, 29 (11-77) seconds during the 3-week waiting period, and 32 (15-72) seconds 3 weeks after entry to the intervention. The contemporary control group's median (IQR) read times were 21 (9-54), 22 (9-63), and 23 (9-60) seconds in corresponding periods. The estimated association of GenAI was a 21.8% increase in read time (95% CI, 5.2% to 41.0%; P = .008), a -5.9% change in reply time (95% CI, -16.6% to 6.2%; P = .33), and a 17.9% increase in reply length (95% CI, 10.1% to 26.2%; P < .001). Participants recognized GenAI's value and suggested areas for improvement. Conclusions and Relevance: In this QI study, GenAI-drafted replies were associated with significantly increased read time, no change in reply time, significantly increased reply length, and some perceived benefits. Rigorous empirical tests are necessary to further examine GenAI's performance. Future studies should examine patient experience and compare multiple GenAIs, including those with medical training.


Assuntos
Inteligência Artificial , Médicos , Adulto , Feminino , Humanos , Comunicação , Eletrônica , Sistemas Computadorizados de Registros Médicos , Masculino , Pessoa de Meia-Idade
2.
J Dent Hyg ; 98(2): 21-29, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38649292

RESUMO

Purpose Social media can be an effective tool in health care education. The purpose of this study was to explore dental hygiene educators' familiarity and use of social media platforms and to examine how social media was implemented in dental hygiene education.Methods A 25-item questionnaire was designed to investigate the use of social media by dental hygiene educators. The instrument included demographic data and items addressing personal, professional, and educational use of twelve common social media sites and the respondents' beliefs about social media using a 4-point Likert scale. The electronic questionnaire was distributed by email to 379 dental hygiene program directors in the United States and Canada. Descriptive statistics were used to analyze the data.Results A total of 120 responses were received. While Facebook was the most utilized site for personal use (78.3%), LinkedIn was the most frequently accessed site for professional use (57.5%), and YouTube for educational use (68.3%). There was strong agreement that the interactive nature of online technologies create better learning environments (84.1%). There was also strong agreement that social media use in the classroom invites student participation (77.5%). More than half of the respondents (64.2%) indicated that social media can be an effective method for content delivery.Conclusion Social media is highly utilized for personal use by dental hygiene educators, but less frequently for engagement purposes in the classroom.


Assuntos
Higienistas Dentários , Mídias Sociais , Humanos , Higienistas Dentários/educação , Inquéritos e Questionários , Estados Unidos , Canadá , Masculino , Feminino , Adulto , Pessoa de Meia-Idade
3.
Pediatr Dent ; 46(1): 63-67, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38449038

RESUMO

Purpose: To describe triazolam in pediatric dental mild to moderate sedation and report changes to overall visit behavior for permanent first molar extraction. Methods: This retrospective chart review from 2018 to 2022 analyzed demographic, procedural, and behavioral data for children eight years and older receiving triazolam for a permanent first molar extraction. The outcomes included adverse events measured by deviations in heart rate and oxygen saturation and changes to overall visit-level Frankl scores from the referral to sedation visit. Descriptive statistics and non-parametric statistical analyses were conducted. Results: The study population (n equals 82) was predominantly female (61 percent), English-speaking (85 percent), and White (41 percent) or Black (39 percent). The most common indication for mild to moderate sedation was dental anxiety (28 percent). There were zero instances of adverse events requiring emergency intervention or the use of reversal medication. The change in visit-level Frankl scores was significantly positive (P<0.001). Conclusion: Triazolam is likely a safe choice for mild to moderate sedation, leading to improved overall visit behavior in children undergoing a permanent first molar extraction.


Assuntos
Triazolam , Humanos , Criança , Feminino , Masculino , Estudos Retrospectivos , Triazolam/efeitos adversos , Frequência Cardíaca , Dente Molar , Encaminhamento e Consulta
4.
J Am Med Inform Assoc ; 30(10): 1665-1672, 2023 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-37475168

RESUMO

OBJECTIVE: Physicians of all specialties experienced unprecedented stressors during the COVID-19 pandemic, exacerbating preexisting burnout. We examine burnout's association with perceived and actionable electronic health record (EHR) workload factors and personal, professional, and organizational characteristics with the goal of identifying levers that can be targeted to address burnout. MATERIALS AND METHODS: Survey of physicians of all specialties in an academic health center, using a standard measure of burnout, self-reported EHR work stress, and EHR-based work assessed by the number of messages regarding prescription reauthorization and use of a staff pool to triage messages. Descriptive and multivariable regression analyses examined the relationship among burnout, perceived EHR work stress, and actionable EHR work factors. RESULTS: Of 1038 eligible physicians, 627 responded (60% response rate), 49.8% reported burnout symptoms. Logistic regression analysis suggests that higher odds of burnout are associated with physicians feeling higher level of EHR stress (odds ratio [OR], 1.15; 95% confidence interval [CI], 1.07-1.25), having more prescription reauthorization messages (OR, 1.23; 95% CI, 1.04-1.47), not feeling valued (OR, 3.38; 95% CI, 1.69-7.22) or aligned in values with clinic leaders (OR, 2.81; 95% CI, 1.87-4.27), in medical practice for ≤15 years (OR, 2.57; 95% CI, 1.63-4.12), and sleeping for <6 h/night (OR, 1.73; 95% CI, 1.12-2.67). DISCUSSION: Perceived EHR stress and prescription reauthorization messages are significantly associated with burnout, as are non-EHR factors such as not feeling valued or aligned in values with clinic leaders. Younger physicians need more support. CONCLUSION: A multipronged approach targeting actionable levers and supporting young physicians is needed to implement sustainable improvements in physician well-being.


Assuntos
Esgotamento Profissional , COVID-19 , Estresse Ocupacional , Médicos , Humanos , Registros Eletrônicos de Saúde , Pandemias , Esgotamento Profissional/epidemiologia
5.
J Med Imaging Radiat Sci ; 53(4S): S100-S106, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36114126

RESUMO

The impact of the COVID-19 pandemic on healthcare providers is well documented and has resulted in significant pressures from a health human resources perspective with many point-of-care providers taking extended leave or moreover, leaving the healthcare sector altogether. As part of a larger Health Human Resources (HHR) strategy at Sunnybrook Health Sciences Centre (Sunnybrook) in Toronto, Canada, a time-limited interprofessional working group titled Supporting Team Sunnybrook (STS) was created. The working group was created to focus on staff retention to respond to ongoing concerns by leaders with regard to staff leaving the organization at an increased rate as documented by our organization's decision support team. Anecdotally, many staff cited their decision to leave the organization as a consequence of the pandemic. As no staff retention committee had been formally created at our organization, STS was established to engage all staff members while addressing and resolving current feedback, concerns, suggestions and issues. The objective of our working group was to review published literature, establish themes from this review, and align these themes to priority themes brought forward by staff through a number of data capture activities. Data capture activities included reviewing existing survey data, new survey data and meetings with staff members. Analysis of the data resulted in the identification of five key consensus areas (priority themes): Staff recognition, wellbeing, grow at Sunnybrook, leaderful leaders, and communication. Our team created five corresponding working groups with the aim to create short- and long-term goals, as well as time sensitive and sustainable operational activities that would contribute to improved staff retention at our organization. Outcomes from our work provided two key learnings to leaders on their ongoing work to retain staff which were the importance of: (1) engagement across all roles, professions including non-clinical team members and support staff and (2) broad communication on the outcomes of our working group to demonstrate that that their feedback was taken seriously and acted upon.


Assuntos
COVID-19 , Liderança , Humanos , Pandemias , Hospitais , Pessoal de Saúde
6.
Sensors (Basel) ; 22(18)2022 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-36146357

RESUMO

Biogenic amines are an important and widely studied class of molecules due to their link to the physiological processes of food-related illnesses and histamine poisoning. Electrochemiluminescent (ECL) detection offers an inexpensive and portable analytical method of detection for biogenic amines when coupled with recent advancements in low-cost carbon-based electrodes and a smartphone camera. In this work, a mobile phone camera was evaluated against a piece of conventional instrumentation, the charge-coupled device, for the detection of ECL from the reaction of biogenic amines with the luminescent compound tris(2,2'-bipyridyl)ruthenium(II). Assisted by a 3D-printed light-tight housing, the mobile phone achieved limits of detection of 127, 425 and 421 µM for spermidine, putrescine, and histamine, respectively. The mobile phone's analytical figures of merit were lesser than the CCD camera but were still within the range to detect contamination. In an exploration of real-world samples, the mobile phone was able to determine the contents of amines in skim milk on par with that of a CCD camera.


Assuntos
Telefone Celular , Compostos Organometálicos , Aminas Biogênicas , Carbono , Histamina , Medições Luminescentes/métodos , Putrescina , Espermidina
7.
JAMA ; 327(18): 1817-1818, 2022 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-35435945
9.
ChemElectroChem ; 7(15): 3244-3252, 2020 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-33542892

RESUMO

Micromolded carbon paste electrodes are easily fabricated, disposable, and can be integrated into microfluidic devices to fabricate inexpensive sensors and biosensors. In this work, carbon paste microelectrodes were fabricated in poly(dimethylsiloxane) using micromolding techniques and were coupled to a microfluidic channel to fabricate electrogenerated chemiluminescent (ECL) sensors. ECL was generated using both the tris(2,2'-bipyridyl)ruthenium(II)-tripropylamine system and the hydrogen peroxide and luminol system. For each of these ECL systems, the sensor fabrication method was optimized, along with key experimental parameters (applied voltage, solution flow rate, buffer species and luminol concentration). The limit of detection (S/N = 3) for TPrA was ~2.4 µM with a linear range of 10-100µM. For hydrogen peroxide the LOD was ~11 µM and the electrodes gave a linear response between 30 µM and 200 µM hydrogen peroxide. Electrodes containing glucose oxidase were fabricated using this new method, demonstrating that glucose could be indirectly detected via generation of hydrogen peroxide by the enzymatic reaction at the micromolded biosensor.

10.
Dent Clin North Am ; 62(2): 235-244, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29478455

RESUMO

Infant oral health (IOH) is a preventive service advocated by major medical and dental organizations. IOH aims to prevent early childhood caries (ECC) and impart health strategies to families for continued oral health and prevention of future caries. IOH reaches across disciplines, is low cost, and is covered by Medicaid and many private dental payers. Increasing evidence points to immediate and long-term positive oral health outcomes of reduced disease, reduction in costly care, and reduction in ECC-associated morbidities.


Assuntos
Saúde Bucal , Odontologia em Saúde Pública , Assistência Odontológica para Crianças , Financiamento da Assistência à Saúde , Humanos , Lactente , Odontologia em Saúde Pública/economia , Estados Unidos
11.
Biochem Biophys Res Commun ; 479(4): 841-846, 2016 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-27687547

RESUMO

Although most cancer drugs target the proliferation of cancer cells, it is metastasis, the complex process by which cancer cells spread from the primary tumor to other tissues and organs of the body where they form new tumors, that leads to over 90% of all cancer deaths. Thus, there is an urgent need for anti-metastasis therapy. Surprisingly, emerging evidence suggests that certain anti-cancer drugs such as paclitaxel and doxorubicin can actually promote metastasis, but the mechanism(s) behind their pro-metastatic effects are still unclear. Here, we use a microfluidic microcirculation mimetic (MMM) platform which mimics the capillary constrictions of the pulmonary and peripheral microcirculation, to determine if in-vivo-like mechanical stimuli can evoke different responses from cells subjected to various cancer drugs. In particular, we show that leukemic cancer cells treated with doxorubicin and daunorubicin, commonly used anti-cancer drugs, have over 100% longer transit times through the device, compared to untreated leukemic cells. Such delays in the microcirculation are known to promote extravasation of cells, a key step in the metastatic cascade. Furthermore, we report a significant (p < 0.01) increase in the chemotactic migration of the doxorubicin treated leukemic cells. Both enhanced retention in the microcirculation and enhanced migration following chemotherapy, are pro-metastatic effects which can serve as new targets for anti-metastatic drugs.


Assuntos
Antineoplásicos/efeitos adversos , Leucemia Promielocítica Aguda/tratamento farmacológico , Microcirculação/efeitos dos fármacos , Fenômenos Biomecânicos , Materiais Biomiméticos , Morte Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Movimento Celular/fisiologia , Daunorrubicina/efeitos adversos , Doxorrubicina/efeitos adversos , Células HL-60 , Humanos , Técnicas In Vitro , Dispositivos Lab-On-A-Chip , Leucemia Promielocítica Aguda/patologia , Leucemia Promielocítica Aguda/fisiopatologia , Metástase Neoplásica
12.
Bioanalysis ; 8(19): 2071-89, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27611228

RESUMO

Electrogenerated chemiluminescence (ECL) is the production of light via electron transfer reactions between electrochemically produced reagents. ECL-based biosensors use specific biological interactions to recognize an analyte and produce a luminescent signal. Biosensors fabricated with novel biorecognition species have increased the number of analytes detected. Some of these analytes include peptides, cells, enzymes and nucleic acids. ECL biosensors are selective, simple, sensitive and have low detection limits. Traditional methods use ruthenium complexes or luminol to generate ECL. Nanomaterials can be incorporated into ECL biosensors to improve efficiency, but also represent a new class of ECL emitters. This article reviews the application of ruthenium complex, luminol and nanomaterial-based ECL biosensors to making measurements in biological matrices over the past 4 years.


Assuntos
Técnicas Biossensoriais , Complexos de Coordenação/química , Medições Luminescentes , Aptâmeros de Nucleotídeos/química , Biomarcadores Tumorais/análise , Biomarcadores Tumorais/sangue , Imunoensaio , Luminol/química , Nanoestruturas/química , Rutênio/química
13.
J Dent Educ ; 79(8): 934-9, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26246532

RESUMO

The aim of this study was to investigate the contribution of a tiered predoctoral pediatric dentistry clinical education model to competency achievement by dental students over a two-year clinical education. Retrospective data were obtained for academic years 2012-13 and 2013-14 from three sources: a campus-based, dental school-housed clinic; division-directed clinics in community-based pediatric and special needs clinics (DDC); and clinics affiliated with the dental college's community-based dental education (CBDE) program, the OHIO Project (OP). A fourth dataset was obtained for the same two-year period from a biannual clinic event held at the college in conjunction with Give Kids a Smile Day (GKAS). Procedures considered essential to the care of children were sorted by 12 dental codes from all services for patients 18 years of age and younger. The dental school clinic provided 11,060 procedures; the DDC, 28,462; the OP, 17,863; and GKAS, 2,028. The two-year total was 59,433 procedures. Numbers of diagnostic and preventive procedures were 19,441, restorative procedures were 13,958, and pulp and surgical procedures were 7,392. Site contribution ranged from 52.2 to 144.9 procedures per attending student, with the DDC yielding the highest per student average for each year (126.4 and 144.9) and the dental school clinic the lowest (52.2 and 53.1). This study found that a combination of school-based, community-based, and philanthropic pediatric dental experiences offered a large number of essential pediatric dentistry experiences for predoctoral dental students, with CBDE opportunities offering the largest contribution.


Assuntos
Assistência Odontológica para Crianças , Educação em Odontologia , Odontopediatria/educação , Preceptoria , Faculdades de Odontologia , Cuidados de Saúde não Remunerados , Adolescente , Criança , Odontologia Comunitária/educação , Centros Comunitários de Saúde/estatística & dados numéricos , Assistência Odontológica para Crianças/estatística & dados numéricos , Assistência Odontológica para a Pessoa com Deficiência/estatística & dados numéricos , Clínicas Odontológicas/estatística & dados numéricos , Humanos , Unidades Móveis de Saúde/estatística & dados numéricos , Ohio , Estudos Retrospectivos , Cuidados de Saúde não Remunerados/estatística & dados numéricos
14.
Bioanalysis ; 5(2): 131-3, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23330555

RESUMO

American Chemical Society Regional Meetings are a convenient and economical route for students, faculty and industry representatives to come together and communicate scientific findings and ideas. This year the 47th American Chemical Society Midwest Regional Meeting was held in Omaha (NE, USA) and included a special symposium on 'New frontiers in bioanalysis'.


Assuntos
Química Farmacêutica/métodos , Imagem Molecular/métodos , Humanos
15.
PLoS One ; 7(10): e47722, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23091642

RESUMO

Dental caries in very young children may be severe, result in serious infection, and require general anesthesia for treatment. Dental caries results from a shift within the biofilm community specific to the tooth surface, and acidogenic species are responsible for caries. Streptococcus mutans, the most common acid producer in caries, is not always present and occurs as part of a complex microbial community. Understanding the degree to which multiple acidogenic species provide functional redundancy and resilience to caries-associated communities will be important for developing biologic interventions. In addition, microbial community interactions in health and caries pathogenesis are not well understood. The purpose of this study was to investigate bacterial community profiles associated with the onset of caries in the primary dentition. In a combination cross-sectional and longitudinal design, bacterial community profiles at progressive stages of caries and over time were examined and compared to those of health. 16S rRNA gene sequencing was used for bacterial community analysis. Streptococcus mutans was the dominant species in many, but not all, subjects with caries. Elevated levels of S. salivarius, S. sobrinus, and S. parasanguinis were also associated with caries, especially in subjects with no or low levels of S. mutans, suggesting these species are alternative pathogens, and that multiple species may need to be targeted for interventions. Veillonella, which metabolizes lactate, was associated with caries and was highly correlated with total acid producing species. Among children without previous history of caries, Veillonella, but not S. mutans or other acid-producing species, predicted future caries. Bacterial community diversity was reduced in caries as compared to health, as many species appeared to occur at lower levels or be lost as caries advanced, including the Streptococcus mitis group, Neisseria, and Streptococcus sanguinis. This may have implications for bacterial community resilience and the restoration of oral health.


Assuntos
Cárie Dentária/microbiologia , RNA Ribossômico 16S/genética , Streptococcus mutans/genética , Bactérias/genética , Bactérias/isolamento & purificação , Biodiversidade , Estudos de Casos e Controles , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Filogenia , Streptococcus mutans/classificação , Streptococcus mutans/isolamento & purificação
16.
PLoS One ; 6(4): e19051, 2011 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-21544197

RESUMO

Comparing bacterial 16S rDNA sequences to GenBank and other large public databases via BLAST often provides results of little use for identification and taxonomic assignment of the organisms of interest. The human microbiome, and in particular the oral microbiome, includes many taxa, and accurate identification of sequence data is essential for studies of these communities. For this purpose, a phylogenetically curated 16S rDNA database of the core oral microbiome, CORE, was developed. The goal was to include a comprehensive and minimally redundant representation of the bacteria that regularly reside in the human oral cavity with computationally robust classification at the level of species and genus. Clades of cultivated and uncultivated taxa were formed based on sequence analyses using multiple criteria, including maximum-likelihood-based topology and bootstrap support, genetic distance, and previous naming. A number of classification inconsistencies for previously named species, especially at the level of genus, were resolved. The performance of the CORE database for identifying clinical sequences was compared to that of three publicly available databases, GenBank nr/nt, RDP and HOMD, using a set of sequencing reads that had not been used in creation of the database. CORE offered improved performance compared to other public databases for identification of human oral bacterial 16S sequences by a number of criteria. In addition, the CORE database and phylogenetic tree provide a framework for measures of community divergence, and the focused size of the database offers advantages of efficiency for BLAST searching of large datasets. The CORE database is available as a searchable interface and for download at http://microbiome.osu.edu.


Assuntos
DNA Ribossômico/genética , Metagenoma/genética , Boca/microbiologia , Humanos , Filogenia
18.
J Clin Microbiol ; 48(11): 4121-8, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20826648

RESUMO

Previous studies have confirmed the association of the acid producers Streptococcus mutans and Lactobacillus spp. with childhood caries, but they also suggested these microorganisms are not sufficient to explain all cases of caries. In addition, health-associated bacterial community profiles are not well understood, including the importance of base production and acid catabolism in pH homeostasis. The bacterial community composition in health and in severe caries of the young permanent dentition was compared using Sanger sequencing of the ribosomal 16S rRNA genes. Lactobacillus species were dominant in severe caries, and levels rose significantly as caries progressed from initial to deep lesions. S. mutans was often observed at high levels in the early stages of caries but also in some healthy subjects and was not statistically significantly associated with caries progression in the overall model. Lactobacillus or S. mutans was found either at low levels or not present in several samples. Other potential acid producers observed at high levels in these subjects included strains of Selenomonas, Neisseria, and Streptococcus mitis. Propionibacterium FMA5 was significantly associated with caries progression but was not found at high levels. An overall loss of community diversity occurred as caries progressed, and species that significantly decreased included the Streptococcus mitis-S. pneumoniae-S. infantis group, Corynebacterium matruchotii, Streptococcus gordonii, Streptococcus cristatus, Capnocytophaga gingivalis, Eubacterium IR009, Campylobacter rectus, and Lachnospiraceae sp. C1. The relationship of acid-base metabolism to 16S rRNA gene-based species assignments appears to be complex, and metagenomic approaches that would allow functional profiling of entire genomes will be helpful in elucidating the microbial pathogenesis of caries.


Assuntos
Bactérias/classificação , Bactérias/genética , Biodiversidade , Cárie Dentária/microbiologia , Metagenoma , Dente/microbiologia , Adolescente , Bactérias/metabolismo , Ácidos Carboxílicos/metabolismo , Criança , Análise por Conglomerados , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Feminino , Humanos , Masculino , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
19.
Bioanalysis ; 1(1): 31-6, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21083185

RESUMO

Microfluidic devices allow for fast detection with little reagent consumption. They also offer portability and the ability to mimic biological systems. Currently, many microfluidic devices are a hybrid of the microchip components, such as flow channels and wells, and larger instrumentation. There is a need to develop miniaturized detectors for lab-on-a-chip applications. Electrochemical detection methods have the advantage of ease of miniaturization. The electrochemical method, electrochemiluminescence, has the potential to be miniaturized and incorporated into a lab-on-a-chip device. As in other electrochemical methods, electrochemiluminescence is straightforward to miniaturize, but also possesses the sensitivity of a fluorescence detection method. In our laboratory, we have been developing carbon ink microelectrodes as the working electrode for a miniaturized electrochemiluminescence system. Since the signal is proportional to the electrode area, the challenge has been to maximize the signal-to-noise ratio and maintain low detection limits as the electrode size decreases.


Assuntos
Técnicas Eletroquímicas , Luminescência , Microeletrodos , Técnicas Analíticas Microfluídicas/instrumentação , Técnicas Analíticas Microfluídicas/métodos , Miniaturização , Técnicas Eletroquímicas/instrumentação , Técnicas Eletroquímicas/métodos , Desenho de Equipamento , Fluorescência , Limite de Detecção , Procedimentos Analíticos em Microchip
20.
Anal Chim Acta ; 613(2): 152-62, 2008 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-18395054

RESUMO

The cyclic voltammetry and electrogenerated chemiluminescent (ECL) reactions of a series of quinolone and fluoroquinolone antibiotics were investigated in a flow injection analysis (FIA) system. 7-Piperazinyl fluoroquinolone antibiotics were found to participate as a coreactant in an oxidative-reductive ECL mechanism with tris(2,2'-bipyridyl)ruthenium(II) (Ru(bpy)(3)(2+)) as the luminescent reagent. The reaction mechanism was investigated in order to understand and optimize the processes leading to light emission. The optimal conditions included a solution pH approximately 7 at a flow rate of 3.0 mL min(-1) with no added organic modifier and application of 1.2V vs. a Pt quasi-reference electrode (QRE). Fluoroquinolones containing a tertiary distal nitrogen on the piperazine ring, such as enrofloxacin and ofloxacin, reacted to produce more intense ECL than those with a secondary nitrogen, such as ciprofloxacin and norfloxacin. The method linear range, precision, detection limits, and sensitivity for the detection of enrofloxacin and ciprofloxacin were compared to that of tripropylamine. The method was applied to the determination of the ciprofloxacin content in a pharmaceutical preparation. The assay is discussed in terms of its analytical figures of merit, ease of use, speed, accuracy and application to pharmaceutical samples.


Assuntos
2,2'-Dipiridil/análogos & derivados , Antibacterianos/química , Quinolonas/química , 2,2'-Dipiridil/química , Complexos de Coordenação , Concentração de Íons de Hidrogênio , Luminescência , Oxirredução , Oxigênio/química , Reprodutibilidade dos Testes
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