Geographical variation in perceptions, attitudes and barriers to mental health care-seeking across the UK: a cross-sectional study.

OBJECTIVES: To examine the relative importance of the drivers of mental health care-seeking intention and how these, along with intention itself, are geographically distributed across integrated care systems (ICS) and health boards (HBs) in the UK. Also, to examine the degree of acceptance of virtual modes of care. DESIGN: Community-based cross-sectional survey. PARTICIPANTS AND SETTING: A national online survey of 17 309 adults between August and September 2021 recruited via a research technology company, Lucid. Sample size quotas were set to ensure coverage across the UK and match population distributions for gender, age and ethnicity. After exclusions, 16 835 participants remained (54% female, 89% white). MAIN OUTCOME MEASURES: Care-seeking intention, using a continuous measure of likelihood and a categorical measure of estimated time to seek professional help for a future mental health difficulty. RESULTS: 20.5% (95% CI 19.8% to 21.2%) reported that they would significantly delay or never seek mental healthcare, ranging from 8.3% to 25.7% across ICS/HBs. Multilevel regression analysis showed mental health knowledge was the most predictive of care-seeking intention, followed by attitudes towards others with mental illness and a combination of stigma, negative attitudes to treatment and instrumental barriers to accessing care. The model explained 17% of the variance. There was substantial geographical variation in prevalence of preclinical symptoms of depression and anxiety, attitudes to mental health, and barriers to care, leading to complex ICS/HB profiles. Remote and self-guided therapies did not pose as a major barrier to care with more than half of respondents likely or very likely to use them. CONCLUSIONS: Our locally relevant and actionable findings suggest possible interventions that may improve care-seeking intention and indicate which of these interventions need to be geographically tailored to have maximal effect.

Freeze casting to engineer gradient porosity in hydroxyapatite-boron nitride nanotube composite scaffold for improved compressive strength and osteogenic potential.

Graded porosity plays a crucial role in scaffolds for bone tissue engineering as it facilitates vital processes such as nutrient diffusion, cellular infiltration, and tissue integration. This paper explores the utilization of freeze casting (FC) as a technique to generate composite scaffolds comprising hydroxyapatite (HA) reinforced with 1D-boron nitride nanotubes (BNNTs) featuring graded porosity and improved compressive strength. Comparative studies were conducted using FC at room and sub-zero temperatures to assess the influence of temperature gradient and heat transfer rate on the production of gradient and aligned porosity in HA-BNNT composites. The FC process with a prolonged thermal gradient facilitated the creation of aligned pores in the HA-BNNT, exhibiting a wide distribution of 60% porosity ranging from 1 to 30 µm. Adding high strength 1 vol% BNNT reinforcement resulted in a remarkable 50% enhancement in compressive strength compared to the control sample. Osteoblasts seeded on the HA-BNNT substrate exhibited significantly higher alkaline phosphate activity, indicating accelerated mineralization compared to the control sample. Gradient porosity and wide pore distribution in the HA-BNNT scaffolds promoted osteogenic activities. Overall, the demonstrated FC processing technique and BNNT addition hold great potential for developing functional and biomimetic scaffolds that can effectively promote tissue regeneration, leading to improved clinical outcomes in bone tissue engineering applications.

Electrically and Thermally Triggered Three-Dimensional Graphene-Foam-Reinforced Shape Memory Epoxy Composites.

Shape memory polymer (SMP) epoxy composites have attracted significant attention due to their easy processing, lightweight nature, and ability to recover strain. However, their limited recovery rate and inferior mechanical properties have hindered their functional applications. This research explores the potential of three-dimensional (3D) graphene foam (GrF) as a highly efficient reinforcement for SMP epoxy composites. We demonstrated that the incorporation of a mere 0.13 wt.% GrF into mold-cast SMP epoxy leads to a 19% increase in the glass transition temperature (Tg). To elucidate the reinforcing mechanism, we fabricated and extensively analyzed composites with varying weight percentages of GrF. The GrF-based SMP epoxy composite exhibits a 57% increase in thermal conductivity, measuring 0.296 W mK-1 at 70 °C, due to the interconnected 3D graphene network within the matrix. Notably, this composite also demonstrates remarkable electrical conductivity, making it suitable for dual-triggering applications. The GrF-SMP epoxy composite achieves a maximum shape recovery ratio and a significant 23% improvement in the recovery rate, effectively addressing the issue of slow recovery associated with SMPs. We investigated the effect of switching temperatures on the shape recovery rate. We identified the optimal triggering temperature to initiate shape recovery for epoxy SMP and GrF-epoxy SMP as thermal energy equivalent to Tg + 20 °C. Additionally, we fabricated a bird-shaped composite using GrF reinforcement, which showcases self-healing capabilities through the crack opening and closure and serves as a tangible demonstration of the transformative potential of the composite. These GrF-epoxy SMP composites, responsive to stimuli, hold immense promise for diverse applications, such as mechanical systems, wearable sensors, morphing wings, foldable robots, and antennas.

On-chip mixing of cancer cells and drug using LED enabled 2D opto-wetting droplet platforms.

Droplets of microliter size serve as miniaturized reaction chambers for practical lab on a chip (LoC) applications. The transportation and coalescence of droplets are indispensable for realizing microfluidic mixing. Light can be used as an effective tool for droplet manipulation. We report a novel platform for LED-based transport and mixing of cell-encapsulated microdroplets for evaluating dose response of cancer drugs. Microcontroller enabled LEDs (Light-emitting diodes) were used to actuate droplet movement on Azobenzene coated planar silicon substrates. Droplet transport was initiated by the spatial gradient in solid-liquid interfacial tension developed through LED triggered photoisomerization of Azobenzene substrate. Detailed UV-Visible characterization of Azobenzene molecule was performed for different LED light intensities and wavelengths. A complete standalone opto-wetting toolbox was developed by integrating various components such as a microcontroller, UV LED (385 nm), blue LED (465 nm), and Azobenzene coated photoresponsive substrate. 2D transport of DI water droplets (10-30µl) along simple trajectories was demonstrated using this device. Subsequently, the proposed opto-wetting platform was used for performing drug evaluation through on-chip mixing of droplets containing cancer cells (A549-Lung cancer cells) and cancer drug (paclitaxel). Separate cell viability analysis was performed using MTT assays, where the cytocompatibility of Azobenzene and UV light (385 nm) on A549 cells were studied. The dosage response of paclitaxel drug was studied using both MTT (3-(4,5-Dimethylthiazolyl-2)-2,5-diphenyltetrazolium bromide) and live-dead cell assays. The results obtained indicate the potential use of our device as a cost-effective, reliable opto-wetting microfluidic platform for drug screening experiments.

Corrosion Behavior of 1D and 2D Polymorphs of Boron Nitride Ceramic.

This study reports a fundamental electrochemical study to understand the corrosion behavior of 1D bulk, free-standing 1D boron nanotube (BNNT) buckypaper and compare it with a sintered 2D hBN nanoplatelet (BNNP) pellet. Tafel analysis indicates that 1D BNNT has superior corrosion resistance with a lower corrosion rate of 0.0026 mils per year (mpy). 2D BNNP, although having similar chemistry to 1D BNNT, resulted in an increased (40 times) corrosion rate of 0.107 mpy. The higher surface area and aspect ratio of BNNT drastically influenced the corrosion kinetics. The scientific outcomes will enable the better design of novel hBN-based corrosion-resistant materials.

Comorbidities in Obsessive-Compulsive Disorder Across the Lifespan: A Systematic Review and Meta-Analysis.

Comorbidities are seen with obsessive-compulsive disorder (OCD) across the lifespan. Neurodevelopmental comorbidities are common in young children, followed by mood, anxiety, and obsessive-compulsive related disorders (OCRDs) in children, adolescents and adults, and neurological and degenerative disorders in the elderly. Understanding comorbidity prevalence and patterns has clinical and research implications. We conducted a systematic review and meta-analysis on comorbidities in OCD across the lifespan, with the objective to, first, estimate age-wise pattern and prevalence of comorbidities with OCD and, second, to examine associations of demographic (age at assessment, gender distribution) and clinical characteristics (age of onset, illness severity) with comorbidities. Four electronic databases (PubMed, EMBASE, SCOPUS, and PsycINFO) were searched using predefined search terms for articles published between 1979 and 2020. Eligible studies, across age, reported original findings on comorbidities and had an OCD sample size of ≥100. We excluded studies that did not use standardised diagnostic assessments, or that excluded patients on the basis of comorbidity. We adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The review protocol has been registered on the International Prospective Register of Systematic Reviews. A comorbidity rate of 69% was found in a pooled sample of more than 15,000 individuals. Mood disorders (major depressive disorder), anxiety disorders (generalised anxiety disorder), neurodevelopmental disorders (NDDs) and OCRDs were the commonest comorbidities. Anxiety disorders prevailed in children, mood disorders in adults, whereas NDDs were similarly prevalent. Higher comorbidity with any psychiatric illness, NDDs, and severe mental disorders was seen in males, vs. females. Illness severity was inversely associated with rates for panic disorder, tic disorders, OCRDs, obsessive compulsive personality disorder, and anorexia nervosa. This systematic review and meta-analysis provides base rates for comorbidities in OCD across the lifespan. This has implications for comprehensive clinical evaluation and management planning. The high variability in comorbidity rates suggests the need for quality, multi-centric, large studies, using prospective designs. Systematic Review Registration: Unique Identifier: CRD42020215904.

ß-hydroxybutyric acid attenuates oxidative stress and improves markers of mitochondrial function in the HT-22 hippocampal cell line.

Ketone bodies have been the topic of research for their possible therapeutic neurotropic effects in various neurological diseases such as Parkinson's disease, dementia, and seizures. However, continuing research on ketone bodies as a prophylactic agent for decreasing the risk for various neurodegenerative diseases is currently required. In this paper, hippocampal HT-22 cells were treated with ß-hydroxybutyric acid at different doses to elucidate the neurotropic effects. In addition, markers of oxidative stress, mitochondrial function, and apoptosis were investigated. As a result, the ketone body (ß-hydroxybutyric acid) showed a significant increase in hippocampal neuronal viability at a moderate dose. Results show that ß-hydroxybutyric acid exhibited antioxidant effect by decreasing prooxidant oxidative stress markers such as reactive oxygen species, nitrite content, and increasing glutathione content leading to decreased lipid peroxidation. Results show that ß-hydroxybutyric acid improved mitochondrial functions by increasing Complex-I and Complex-IV activities and showing that ß-hydroxybutyric acid significantly reduces caspase-1 and caspase-3 activities. Finally, using computational pharmacokinetics and molecular modeling software, we validated the pharmacokinetic effects and pharmacodynamic (N-Methyl-D-aspartic acid and acetylcholinesterase) interactions of ß-hydroxybutyric acid. The computational studies demonstrate that ß-hydroxybutyric acid can interact with N-Methyl-D-aspartic acid receptor and cholinesterase enzyme (the prime pharmacodynamic targets for cognitive impairment) and further validates its oral absorption, distribution into the central nervous system. Therefore, this work highlights the neuroprotective potential of ketone bodies in cognitive-related neurodegenerative diseases.

A Facile and Scalable Approach in the Fabrication of Tailored 3D Graphene Foam via Freeze Drying.

One of the challenges in the processing of advanced composite materials with 2D reinforcement is their extensive agglomeration in the matrix. 3D architecture of 2D graphene sheets into a Graphene Foam (GrF) assembly has emerged as an effective way to overcome agglomeration. The highly reticulated network of branches and nodes of GrF offers a seamless pathway for photon and electron conduction in the matrix along with improved mechanical properties. 3D GrF nano-filler is often fabricated by chemical vapor deposition (CVD) technique, which demands high energy, slow deposition rate, and restricting production to small scale. This work highlights freeze-drying (FD) technique to produce 3D graphene nanoplatelets (GNP) foam with a similar hierarchical structure to the CVD GrF. The FD technique using water as the main chemical in 3D GNP foam production is an added advantage. The flexibility of the FD in producing GNP foams of various pore size and morphology is elucidated. The simplicity with which one can engineer thermodynamic conditions to tailor the pore shape and morphology is presented here by altering the GNP solid loading and mold geometry. The FD 3D GNP foam is mechanically superior to CVD GrF as it exhibited 1280 times higher elastic modulus. However, thermal diffusivity of the FD GNP foam is almost 0.5 times the thermal diffusivity of the CVD GrF due to the defects in GNP particles and pore architecture. The versatility in GNP foam scalability and compatibility to form foam of other 1D and 2D material systems (e.g., carbon nanotubes, boron nitride nanotubes, and boron nitride nanoplatelets) brings a unique dimensionality to FD as an advanced engineering foam development process.

Diminished distractor exclusion for magnocellular features near the hand.

The modulated visual pathway (MVP) hypothesis attempts to explain a range of differences observed in the processing of objects in the proximal as compared to the distal region of the hand. However, there has been no account of how 'hand proximity' interacts with task relevance within the MVP framework. In the present study, we used a visual search task to test whether the task relevance of a unique feature (motion in Expt. 1, and color in Expt. 2) influences its processing with respect to the hand. The feature was either relevant (Expt. 1a and 2a) or irrelevant (Expt. 1b and 2b) to the search task. The hand proximity effect was observed only in the experiments in which the unique feature was task irrelevant. However, the effect of hand proximity was overridden when the unique feature was predictive of the target location. We propose that it is difficult to accomplish active distractor rejection of magnocellular features near the hand. Similarly, there is improved active distractor rejection of parvocellular features in the distal region of the hand. Overall, the results suggest that processes involving active distractor rejection may drive the attentional effect of hand proximity.

Extrusion 3D Printing of Porous Silicone Architectures for Engineering Human Cardiomyocyte-Infused Patches Mimicking Adult Heart Stiffness.

Cardiac patches, three-dimensional (3D) constructs of polymer scaffold and heart muscle cells, have received widespread attention for regenerative therapy to repair damaged heart tissue. The implanted patches should mimic the micromechanical environment of native myocardium for effective integration and optimum mechanical function. In this study, we engineered compliant silicone scaffolds infused with cardiomyocytes (CMs) differentiated from human-induced pluripotent stem cells. Porous scaffolds are fabricated by extrusion 3D printing of room-temperature-vulcanized (RTV) silicone rubber. The stiffness and strength of scaffolds are tailored by designing a polymer strand arrangement during 3D printing. Single-strand scaffold design is found to display a tensile Young's modulus of ∼280 kPa, which is optimum for supporting CMs without impairing their contractility. Uniform distribution of cells in the scaffold is observed, ascribed to 3D migration facilitated by interconnected porous architecture. The patches demonstrated synchronized contraction 10 days after seeding scaffolds with CMs. Indentation measurements reveal that the contracting cell-scaffold patches display local moduli varying from ∼270 to 530 kPa, which covers the upper spectrum of the stiffness range displayed by the human heart. This study demonstrates the effectiveness of a porous 3D scaffold composed of flexible silicone rubber for CMs percolation, supporting a contractile activity, and mimicking native heart stiffness.

Vocational challenges in severe mental illness: A qualitative study in persons with professional degrees.

BACKGROUND: Employment is a significant stepping stone towards recovery for persons with severe mental illness. In the last two decades there has been increasing focus on obtaining professional courses and degrees for employment in India. AIM: To understand the challenges faced by persons with severe mental illness with professional degrees in obtaining and maintaining employment. METHODS: We interviewed 31 individuals with severe mental illness, who had professional degrees, using qualitative interviews. These interviews explored factors that facilitated as well as those that hindered the process of obtaining and sustaining jobs. RESULTS: Factors that were identified as facilitators for obtaining and maintaining employment included personal strengths, social support, accommodative work environment, disclosure, support from mental health professionals and services. Factors that were identified as hindering for obtaining and maintaining employment included symptoms of the illness, side effects of medications, stigma, poor social support, academic underachievement, disjointed work history, poor workplace environment and specific cultural, gender issues. CONCLUSION: Factors such as workplace accommodations, creating an environment that is permissive of disclosure, using family support and support from mental health professionals will facilitate employment. Addressing factors that hinder such as stigma, academic under-achievement, improving workplace environments, social support will also be important in vocational recovery.

Slower attentional disengagement but faster perceptual processing near the hand.

Many recent studies have reported altered visual processing near the hands. However, there is no definitive agreement about the mechanisms responsible for this effect. One viewpoint is that the effect is predominantly attentional while others argue for the role of pre-attentive perceptual differences in the manifestation of the hand-proximity effect. However, in most of the studies pre-attentional and attentional effects have been conflated. We argue that it is important to dissociate the effect of hand proximity on perception and attention to better theorize and understand how visual processing is altered near the hands. We report two experiments using a visual search task where participants completed a visual search task with their hands either on the monitor or on their lap. When on the monitor, the target could appear near the hand or farther away. In experiment 1, a letter search task showed steeper search slope near the hand suggesting slower attentional disengagement. However, the intercept was smaller in the near hand condition suggesting faster perceptual processing. These results were also replicated in experiment 2 with a conjunction search task with target present and absent conditions and 4 set sizes. The results suggest that there are dissociable effects of hand proximity on perception and attention. Importantly, the pre-attentive advantage of hand proximity does not translate to attentional benefit, but a processing cost. The results of experiment 2 additionally indicate that the steeper slope does not arise from any spatial biases in how search proceeds, but an indicator of slower attentional processing near the hands. The results also suggest that the effect of hand proximity on attention is not spatially graded whereas its effect on perceptuo-motor processes seems to be.

Performance in noise: Impact of reduced speech intelligibility on Sailor performance in a Navy command and control environment.

Noise, hearing loss, and electronic signal distortion, which are common problems in military environments, can impair speech intelligibility and thereby jeopardize mission success. The current study investigated the impact that impaired communication has on operational performance in a command and control environment by parametrically degrading speech intelligibility in a simulated shipborne Combat Information Center. Experienced U.S. Navy personnel served as the study participants and were required to monitor information from multiple sources and respond appropriately to communications initiated by investigators playing the roles of other personnel involved in a realistic Naval scenario. In each block of the scenario, an adaptive intelligibility modification system employing automatic gain control was used to adjust the signal-to-noise ratio to achieve one of four speech intelligibility levels on a Modified Rhyme Test: No Loss, 80%, 60%, or 40%. Objective and subjective measures of operational performance suggested that performance systematically degraded with decreasing speech intelligibility, with the largest drop occurring between 80% and 60%. These results confirm the importance of noise reduction, good communication design, and effective hearing conservation programs to maximize the operational effectiveness of military personnel.

Economic impact of early intervention in psychosis services: results from a longitudinal retrospective controlled study in England.

OBJECTIVES: To demonstrate the costs, outcomes and economic impact of early intervention in psychosis (EIP) services. DESIGN: Longitudinal retrospective observational study of service usage and outcome data from mental health and acute care services for all those with a diagnosis of psychosis in contact with mental health services over a 3-year period (April 2010-March 2013). SETTING: Thames Valley and South Midlands region in England (region covered by Oxford Academic Health Science Network). PARTICIPANTS: 3674 people with psychosis, aged 16-35 years. INTERVENTIONS: EIP team or other community mental health teams. MAIN OUTCOME MEASURES: Change in housing status, change in employment status and improvement on each of the four domains of the Health of the Nation Outcome Scale (HONOS) questionnaire. Costs of mental and acute health inpatient, outpatient and community service use were also included in the study. RESULTS: Patients in EIP services were 116% more likely (95% CI 1.263 to 3.708) to gain employment, 52% more likely to become accommodated in a mainstream house (95% CI 0.988 to 2.326) and 17% more likely to have an improvement in the emotional well-being domain of the HONOS questionnaire (95% CI 1.067 to 1.285), as compared to those in non-EIP services. Annual National Health Service (NHS) costs were also significantly lower for patients using EIP services compared to non-users. The mean annual NHS cost savings associated with EIP were £4031 (95% CI £1281 to £6780). These mostly came from lower mental health inpatient costs (£4075, 95% CI £1164 to £6986), lower acute hospital outpatient costs (£59, 95% CI £9 to £109), lower accident and emergency costs (£31, 95% CI £12 to £51), and higher mental health community costs (£648, 95% CI £122 to £1175). If all people with a first-episode psychosis across England were to be treated by EIP services, the savings in societal costs would be an estimated £63.3 million per year, of which £33.5 million would be in NHS costs. CONCLUSIONS: Treatment within an EIP service is associated with better health and social outcomes, and reduced costs.

The effect on the flexural strength, flexural modulus and compressive strength of fibre reinforced acrylic with that of plain unfilled acrylic resin - an in vitro study.

AIM: The aim of this in vitro study was to compare the flexural strength, the flexural modulus and compressive strength of the acrylic polymer reinforced with glass, carbon, polyethylene and Kevlar fibres with that of plain unfilled resin. MATERIALS AND METHODS: A total of 50 specimens were prepared and divided into 10 specimens each under 5 groups namely group 1- control group without any fibres, group 2 - carbon fibres, group 3- glass fibres, group 4 - polyethylene, group 5- Kevlar. Universal testing machine (Tinius olsen, USA) was used for the testing of these specimens. Out of each group, 5 specimens were randomly selected and testing was done for flexural strength using a three point deflection test and three point bending test for compressive strength and the modulus was plotted using a graphical method. Statistical analysis was done using statistical software. RESULTS: The respective mean values for samples in regard to their flexural strength for PMMA plain, PMMA+ glass fibre, PMMA+ carbon, PMMA+ polyethylene and PMMA+ Kevlar were 90.64, 100.79, 102.58, 94.13 and 96.43 respectively. Scheffes post hoc test clearly indicated that only mean flexural strength values of PMMA + Carbon, has the highest mean value. One-way ANOVA revealed a non-significant difference among the groups in regard to their compressive strength. CONCLUSION: The study concludes that carbon fibre reinforced samples has the greatest flexural strength and greatest flexural modulus, however the compressive strength remains unchanged.

Pristine multi-walled carbon nanotubes/SDS modified carbon paste electrode as an amperometric sensor for epinephrine.

An amperometric sensor for the determination of epinephrine (EP) was fabricated by modifying the carbon paste electrode (CPE) with pristine multi-walled carbon nanotubes (pMWCNTs) using bulk modification followed by drop casting of sodium dodecyl sulfate (SDS) onto the surface for its optimal potential application. The modified electrode showed an excellent electrocatalytic activity towards EP by decreasing the overpotential and greatly enhancing the current sensitivity. FE-SEM images confirmed the dispersion of pMWCNTs in the CPE matrix. EDX analysis ensured the surface coverage of SDS. A comparative study of pMWCNTs with those of oxidized MWCNTs (MWCNTsOX) modified electrodes reveals that the former is the best base material for the construction of the sensor with advantages of lower oxidation overpotential and the least background current. The performance of the modified electrode was impressive in terms of the least charge transfer resistance (Rct), highest values for diffusion coefficient (DEP) and standard heterogeneous electron transfer rate constant (k°). Analytical characterization of the modified electrode exhibited two linear dynamic ranges from 1.0×10(-7) to 1.0×10(-6)M and 1.0×10(-6) to 1.0×10(-4)M with a detection limit of (4.5±0.18)×10(-8)M. A 100-fold excess of serotonin, acetaminophen, folic acid, uric acid, tryptophan, tyrosine and cysteine, 10-fold excess of ascorbic acid and twofold excess of dopamine do not interfere in the quantification of EP at this electrode. The analytical applications of the modified electrode were demonstrated by determining EP in spiked blood serum and adrenaline tartrate injection. The modified electrode involves a simple fabrication procedure, minimum usage of the modifier, quick response, excellent stability, reproducibility and anti-fouling effects.

Multi-walled carbon nanotube/poly(glycine) modified carbon paste electrode for the determination of dopamine in biological fluids and pharmaceuticals.

A modified carbon paste electrode (CPE) for the selective detection of dopamine (DA) in presence of large excess of ascorbic acid (AA) and uric acid (UA) at physiological pH has been fabricated by bulk modification of CPE with multi-walled carbon nanotubes (MWCNTs) followed by electropolymerization of glycine (Gly). The surface morphology is compared using SEM images. The presence of nitrogen was confirmed by the energy dispersion X-ray spectroscopy (EDS) indicating the polymerization of Gly on the surface of the modified electrode. The impedance study indicates a better charge transfer kinetics for DA at CPE modified with MWCNT/polyglycine electrode. The presence of MWCNTs in carbon paste matrix triggers the extent of electropolymerization of Gly and imparts more selectivity towards DA by electrochemically not sensing AA below a concentration of 3.1×10(-4)M. Due to the exclusion of the signal for AA, the interference of AA in the determination of DA is totally ruled out by DPV method which is used for its detection at lower concentrations. Large peak separation, good sensitivity, reproducibility and stability allow this modified electrode to analyze DA individually and simultaneously along with AA and UA. Detection limit of DA was determined from differential pulse voltammetric (DPV) study and found to be 1.2×10(-8)M with a linear dynamic range of 5.0×10(-7)M to 4.0×10(-5)M. The practical analytical application of this electrode was demonstrated by measurement of DA content in dopamine hydrochloride injection and human blood serum.

Multi-walled carbon nanotube modified carbon paste electrode as an electrochemical sensor for the determination of epinephrine in the presence of ascorbic acid and uric acid.

A biocompatible electrochemical sensor for selective detection of epinephrine (EP) in the presence of 1000-fold excess of ascorbic acid (AA) and uric acid (UA) was fabricated by modifying the carbon paste electrode (CPE) with multi-walled carbon nanotubes (MWCNTs) using a casting method. The electro-catalytic activity of the modified electrode for the oxidation of EP was investigated. The current sensitivity of EP was enhanced to about five times upon modification. A very minimum amount of modifier was used for modification. The voltammetric response of EP was well resolved from the responses of AA and UA. The electrochemical impedance spectroscopic (EIS) studies reveal the least charge transfer resistance for the modified electrode. The AA peak that is completely resolved from that of EP at higher concentrations of AA and the inability of the sensor to give an electrochemical response for AA below a concentration of 3.0×10(-4)M makes it a unique electrochemical sensor for the detection of EP which is 100% free from the interference of AA. Two linear dynamic ranges of 1.0×10(-4)-1.0×10(-5) and 1.0×10(-5)-5.0×10(-7)M with a detection limit of 2.9×10(-8)M were observed for EP at modified electrode. The practical utility of this modified electrode was demonstrated by detecting EP in spiked human blood serum and EP injection. The modified electrode is highly reproducible and stable with anti fouling effects.