Portable Monitoring Research Articles

Efficacy of portable sleep monitoring device in diagnosing central sleep apnea in patients with congestive heart failure.

Central sleep apnea (CSA) is a common and serious comorbidity mainly occurring in patients with heart failure (HF), which tends to be underdiagnosed and has not been widely studied. Overnight polysomnography (PSG) is the gold standard for diagnosing CSA; however, the time and expense of the procedure limit its applicability. Portable monitoring (PM) devices are convenient and easy to use; however, they have not been widely studied as to their effectiveness in detecting CSA in patients with HF. In the current study, we examined the diagnostic value of PM as a screening tool to identify instances of CSA among patients with HF. A total of 22 patients under stable heart failure conditions with an ejection fraction of <50% were enrolled. All patients underwent PM and overnight PSG within a narrow time frame. The measurements of the apnea-hypopnea index (AHI), hypopnea index (HI), central apnea index (CAI), and obstructive apnea index (OAI) obtained from PSG, automatic scoring, and manual scoring of PM were recorded. The results obtained from PSG and those from PM (automatic and manual scoring) were compared to assess the accuracy of PM. Among the patients, CSA in 11 patients was found by PSG. The AHI measurements performed using manual scoring of PM showed a significant correlation with those performed using PSG (r = 0.69; P = 0.01). Nonetheless, mean AHI measurements showed statistically significant differences between PSG and automatic scoring of PM (40.0 vs. 23.7 events/hour, respectively; P < 0.001), as well as between automatic and manual scoring of PM (23.7 vs. 29.5 events/hour; P < 0.001). Central sleep apnea was detected by PM; however, the results were easily misread as obstructive apnea, particularly in automatic scoring. PM devices could be used to identify instances of central sleep apnea among patients with HF. The results from PM were well-correlated with standard PSG results, and manual scoring was preferable to automated scoring.

PORTABLE SMART MINI PATIENT MONITOR FOR IMPROVED HEALTHCARE OUTCOMES: PATIENT-BASED CARE DEVICE

&#x0D; &#x0D; &#x0D; &#x0D; &#x0D; This study aims to present the prototype for Portable Smart Mini Patient Monitor for improved healthcare outcomes and patient-based care that records and displays the vital physiological signs including heartbeats, body temperature, ECG, and SPO2. The device has designed with multiple sensors connected with Arduino UNO and interfaced with an LCD display that provide real-time acquisition of the patient’s data. The recent era of medical advancement and digitization has embarked on the need for efficient and innovative medical devices that provide better admittance to competent and dynamic patient care like the smart mini patient monitor to facilitate substantial diagnosis and treatment of patients’ medical diseases by accurately identifying the pattern and effect of the ailment along with the improved patient experience and healthcare outcomes. The research aims to provide better healthcare opportunities to the patients on daily bases and improve the overall healthcare delivery system and make it work simultaneously with the increased population yearning for medical attention. The smart mini patient monitor was used for the detection of vital signs for five human subjects. The acquired results were then calibrated with a thermometer and BIOPAC device. The main idea of the study dwells upon the incorporation of multiple sensors into one portable device that yields multiple physiological signals at one time with utmost precision and can be easily tracked, stored, and&#x0D; &#x0D; &#x0D; &#x0D; &#x0D; &#x0D; &#x0D; used for medical diagnosis.&#x0D; &#x0D; &#x0D; &#x0D; &#x0D;

Facile design of flexible Pd nanoclusters sensitized reduced graphene oxide paper film towards hydrogen sensing

Developing flexible gas sensors based on reduced graphene oxide (rGO) are highly promising for practical application, however, it is still challenging due to the sacrificed solution-processibility and mechanical properties after reduction. To address this issue, we here introduce solution-processed rGO and designed a flexible hydrogen (H2) film sensor by coupling with Pd nanoclusters as the activators via direct colloids mixing and subsequent vacuum filtration. The rGO/Pd nanocluster film features with structural compactness, surface homogeneity, excellent mechanical flexibility, high-efficiency output, and simplification of compositing method. In addition, the film sensor exhibited high response value, fast behavior and stable sensing behavior towards high-concentration H2 compared with bare rGO film owing to the significant activation role of Pd nanoclusters with ultrasmall sizes (average size: 3.3 nm). Conclusively, this work provides an ingenious and effective way for the design of rGO-based flexible sensor, and shows promise for efficient portable and cost-effective monitoring of environmentally H2 gases leaks.

A High-Sensitivity Bowel Sound Electronic Monitor Based on Piezoelectric Micromachined Ultrasonic Transducers.

Bowel sounds contain some important human physiological parameters which can reflect information about intestinal function. In this work, in order to realize real-time monitoring of bowel sounds, a portable and wearable bowel sound electronic monitor based on piezoelectric micromachined ultrasonic transducers (PMUTs) is proposed. This prototype consists of a sensing module to collect bowel sounds and a GUI (graphical user interface) based on LabVIEW to display real-time bowel sound signals. The sensing module is composed of four PMUTs connected in parallel and a signal conditioning circuit. The sensitivity, noise resolution, and non-linearity of the bowel sound monitor are measured in this work. The result indicates that the designed prototype has high sensitivity (-142.69 dB), high noise resolution (50 dB at 100 Hz), and small non-linearity. To demonstrate the characteristic of the designed electronic monitor, continuous bowel sound monitoring is performed using the electronic monitor and a stethoscope on a healthy human before and after a meal. Through comparing the experimental results and analyzing the signals in the time domain and frequency domain, this bowel sound monitor is demonstrated to record bowel sounds from the human intestine. This work displays the potential of the sensor for the daily monitoring of bowel sounds.

Machine learning-assisted Te–CdS@Mn3O4 nano-enzyme induced self-enhanced molecularly imprinted ratiometric electrochemiluminescence sensor with smartphone for portable and visual monitoring of 2,4-D

Here, a novel and portable machine learning-assisted smartphone-based visual molecularly imprinted ratiometric electrochemiluminescence (MIRECL) sensing platform was constructed for highly selective sensitive detection of 2,4-Dichlorophenoxyacetic acid (2,4-D) for the first time. Te doped CdS-coated Mn3O4 (Te–CdS@Mn3O4) with catalase-like activity served as cathode-emitter, while luminol as anode luminophore accompanied H2O2 as co-reactant, and Te–CdS@Mn3O4 decorated molecularly imprinted polymers (MIPs) as recognition unit, respectively. Molecular models were constructed and MIP band and binding energies were calculated to elucidate the luminescence mechanism and select the best functional monomers. The peroxidase activity and the large specific surface area of Mn3O4 and the electrochemical effect can significantly improve the ECL intensity and analytical sensitivity of Te–CdS@Mn3O4. 2,4-D-MIPs were fabricated by in-situ electrochemical polymerization, and the rebinding of 2,4-D inhibits the binding of H2O2 to the anode emitter, and with the increase of the cathode impedance, the ECL response of Te–CdS@Mn3O4 decreases significantly. However, the blocked reaction of luminol on the anode surface also reduces the ECL response. Thus, a double-reduced MIRECL sensing system was designed and exhibited remarkable performance in sensitivity and selectivity due to the specific recognition of MIPs and the inherent ratio correction effect. Wider linear range in the range of 1 nM–100 μM with a detection limit of 0.63 nM for 2,4-D detection. Interestingly, a portable and visual smartphone-based MIRECL analysis system was established based on the capture of luminescence images by smartphones, classification and recognition by convolutional neural networks, and color analysis by self-developed software. Therefore, the developed MIRECL sensor is suitable for integration with portable devices for intelligent, convenient, and fast detection of 2,4-D in real samples.

Ambulance Path Clearance System With Health Monitoring Using Internet of Things

Countless people’s lives are jeopardized in India’s crowded metropolitan metropolises due to ambulances stuck in traffic. Most of the time, commuters are unable to move in these traffic jams to make way for approaching ambulances which has become one of the most pressing issues in India. The main reason in the back of that is growing population which ends up in multiplied number of cars, due to which emergency provider like ambulance gets affected. This paper proposes a solution to make such offerings effortlessly available to those in need. It includes a software application referred to as Ambulance service through which the user can book the ambulance with one faucet and track the ambulance by using Google map on his device, we also use microcontroller-based hardware module to provide an easy flow for ambulance to attain the preferred destination This is achieved by using imposing RF technology which might automatically control the visitors alerts within the course of ambulance accordingly minimizing the time required to reach the destination. Besides this, a portable health monitoring device will be placed in the ambulance which will measure patient’s body temperature, blood pressure which will be displayed in the hospital’s webpage.

Safety and efficacy of using portable coagulation monitor for INR examination after left-sided mechanical prosthetic valve replacement

BackgroundTime in therapeutic range (TTR) is an index to assess the effectiveness of anticoagulation and is important to predict the risk of bleeding and thrombosis in patients taking warfarin. In recent years, the portable coagulation monitor, a point-of-care testing device for patients to perform self-management international normalized ratio (INR) examination, has provided an opportunity to improve the quality of oral warfarin treatment. In this study, we applied TTR to evaluate the safety and efficacy of the portable coagulation monitor for patients with oral anticoagulant warfarin after left-sided mechanical prosthetic valve (MPV) replacement.MethodsIt is a single-centre cohort study. From September 2019 to June 2021, a total of 243 patients who returned to our institution for outpatient clinic revisit at 3 months after left-sided MPV replacement, met the inclusion criteria and agreed to be followed up were included. Self-management group used portable coagulation monitor for INR examination, and patients in the conventional group had their INR monitored in routine outpatient visits. Clinical data of the patients would be recorded for the next 12 months, and results were compared between the two groups to assess the effect of the coagulation monitor on TTR and complications related to bleeding and thrombosis in patients with left-sided MPV replacement.ResultsA total of 212 individuals provided complete and validated INR data spanning of 1 year. Those who applied the portable coagulation monitor had higher TTR values and larger number of tests for INR. No significant differences were seen between the two groups in postoperative bleeding and thromboembolic complications, but portable coagulation monitor showed a trend toward fewer bleeding events.ConclusionPortable devices for coagulation monitoring are safe and can achieve a higher TTR. Patients who use the portable coagulation monitor for home INR self-management can achieve a safe and effective warfarin therapy.

Dynamic performance verification of the Rędziński Bridge using portable camera-based vibration monitoring systems

The assessment of dynamic performance of large-scale bridges typically relies on the deployment of wired instrumentation systems requiring direct contact with the tested structures. This can obstruct their operation and create unnecessary risks to the involved personnel and equipment. These problems can be readily avoided by using non-contact instrumentation systems. However, the cost of off-the-shelf commercial products often prevents their wide adoption in engineering practice. To this end, the dynamic performance of the biggest one-pylon cable-stayed bridge in Poland is investigated based on data from a consumer-grade digital camera and open access image-processing algorithms. The quality of these data is benchmarked against data obtained from conventional wired accelerometers and a high-end commercial optical motion capture system. Operational modal analysis is conducted to extract modal damping, which has a potential to serve as an indicator of structural health. The dynamic properties of the bridge are evaluated against the results obtained during a proof loading exercise undertaken prior to the bridge opening. It is shown that a vibration monitoring system based on consumer-grade digital camera can indeed provide an economically viable alternative to monitoring the complex time-evolving dynamic behaviour patterns of large-scale bridges.

The short term adaptation of the autonomic nervous systems (ANS) by type of urban environment and ethnicity

BackgroundPrevious studies examined the effects of urban environments on the Autonomic Nervous System (ANS). These studies measured the effects of environments on Heart Rate Variability (HRV) averaging different time intervals to one value. Yet, the dynamics of change, reflecting the functions and their derivatives that describe the adaptation to the new environments remain unknown. In addition, ethnic differences in the ANS adaptation were not investigated.Method: Forty-eight Arab and 24 Jewish women ages 20–35 years, all healthy, non-smokers were recruited by a snowball sample. Both groups were of a similar socioeconomic status and BMI distributions. Using a portable monitor, the HRV response was continuously analyzed for 35 min of sedentary sitting in each of the three environments: a park, a city center and a residential area. LF/HF polynomial function was adapted to describe the dynamic change in each environment for each ethnic group. ResultsGreen area exposure was associated with 90% immediate change while in built-up areas, the change in HRV is about 40% adaptive (changing gradually). The adaptive process of HRV may stabilize after 15 min in the city center yet not even after 35 min in the residential environment. The total change (immediate + adaptive) reached 24% in city centers and 10% in residential areas. Changes in HRV rates in the park and the city center environments were higher among Arab women as compared to Jewish women but similar between the two groups in the residential area. The distributions of LF/HF in each time cohort were normal, meaning that shifting the focus to analyze functions of change in HRV, opens the possibility to employ analytic methods that assume the normal distribution. ConclusionsChanging the focus from average levels of HRV to functions of change and their derivatives brings new insight into the understanding of the ANS response to environmental challenges. ANS short term adaptation to different environments is gradual and spans differently both in magnitude of response and latencies between different environments. Importantly, in green areas, the response is immediate unlike the adaptation to urban environments that is significantly more gradual. The ethnic differences in ANS adaptation is also noteworthy. In addition, adaptation proceeesses are normaly distributed in each time cohort suggesting a possible novel ANS index.

Application of VCSEL in Bio-Sensing Atomic Magnetometers.

Recent years have seen rapid development of chip-scale atomic devices due to their great potential in the field of biomedical imaging, namely chip-scale atomic magnetometers that enable high resolution magnetocardiography (MCG) and magnetoencephalography (MEG). For atomic devices of this kind, vertical cavity surface emitting lasers (VCSELs) have become the most crucial components as integrated pumping sources, which are attracting growing interest. In this paper, the application of VCSELs in chip-scale atomic devices are reviewed, where VCSELs are integrated in various atomic bio-sensing devices with different operating environments. Secondly, the mode and polarization control of VCSELs in the specific applications are reviewed with their pros and cons discussed. In addition, various packaging of VCSEL based on different atomic devices in pursuit of miniaturization and precision measurement are reviewed and discussed. Finally, the VCSEL-based chip-scale atomic magnetometers utilized for cardiac and brain magnetometry are reviewed in detail. Nowadays, biosensors with chip integration, low power consumption, and high sensitivity are undergoing rapid industrialization, due to the growing market of medical instrumentation and portable health monitoring. It is promising that VCSEL-integrated chip-scale atomic biosensors as featured applications of this kind may experience extensive development in the near future.

Sleep Disordered Breathing in Children

Sleep disordered breathing (SDB) is a disease characterized by repeated hypopnea and apnea during sleep due to complete or partial obstruction of upper airway. The prevalence of pediatric SDB is approximately 12 - 15%, and the most common age group is preschool children aged 3 - 5 years. Children show more varied presentations, from snoring and frequent arousals to enuresis and hyperactivity. The main cause of pediatric SDB is obstruction of the upper airway related to enlarged tonsils and adenoids. If SDB is left untreated, it can cause complications such as learning difficulties, cognitive impairment, behavioral problems, cardiovascular disease, metabolic syndrome, and poor growth. Pediatric dentists are in a special position to identify children at risk for SDB. Pediatric dentists recognize clinical features related to SDB, and they should screen for SDB by using the pediatric sleep questionnaire (PSQ), lateral cephalometry radiograph, and portable sleep monitoring test and refer to sleep specialists. As a therapeutic approach, maxillary arch expansion treatment, mandible advancement device, and lingual frenectomy can be performed. Pediatric dentists should recognize that prolonged mouth breathing, lower tongue posture, and ankyloglossia can cause abnormal facial skeletal growth patterns and sleep problems. Pediatric dentists should be able to prevent these problems through early intervention.

Outpatient long-term video EEG as new diagnostic approach in Germany: results of a feasibility study

In Germany, long-term video EEG as the gold standard for the diagnostics of epilepsy and other seizure disorders, is currently only available for inpatient monitoring in alimited number of specialized centers. These limited monitoring capacities and the large amount of associated time and work resources lead to asignificant waiting time for this important diagnostic procedure nationwide. New portable sensor technology and automated data analysis methods are creating opportunities for gold standard long-term video EEG assessments in outpatient settings, which may help to resolve this barrier. Here, we report the results of asingle-center feasibility study by implementing outpatient long-term video EEG (ALVEEG) as adiagnostic pathway in Germany. In the new diagnostic pathway, the use of innovative, portable video EEG monitoring systems along with artificial intelligence-assisted data analysis are intended to provide those patients affected by seizure disorders with amore rapid, efficient, and cross-sectoral access to gold standard diagnostics in the home environment. The diagnostics were well accepted by patients and clinicians and may represent acomplementary option to inpatient monitoring to eliminate current bottlenecks in diagnostics and care.

Trichromatic ratiometric fluorescent sensor based on machine learning and smartphone for visual and portable monitoring of tetracycline antibiotics

In this work, a tri-color ratiometric fluorescent optical device integrated with machine learning-assisted smartphones is designed for the visual monitoring of tetracycline antibiotics. The trichromatic sensing probe consists of blue emitting carbon dots (BCDs) at 420 nm, and red-emitting bovine serum albumin-protected copper nanoclusters (BSA-Cu NCs) at 635 nm, as well as an emission peak at 520 nm, rises in the presence of tetracycline antibiotics (TCs), therefore, a three emission system is formed. BCDs/BSA-Cu NCs present three emission responses to TCs, which are based on the internal filtering effect (IFE) and the sensitization mechanisms with BSA. The reaction mechanism was verified by density functional theory (DFT) and a series of characterizations, such as infrared spectrum, ultraviolet absorption spectrum, and fluorescence lifetime. Interestingly, the fluorescence intensity of BCDs was quenched by TCs, and due to the sensitization between BSA and TCs, a green fluorescence rose at 520 nm, while the peak of BSA-Cu NCs remained stable, resulting in a significant color shift from red to cyan. Therefore, the ratiometric fluorescence intensity of I(635+520)/I420 can be used to determine TCs, and the colors change can be used to identify the quantitative analysis. In addition, the deep learning of the YOLO v3 algorithm assists the integrated tri-color portable optical device of smartphones, which can realize the visual detection of TCs. In general, the sensing system has many advantages, such as good stability, specificity, and rich color changes, which provide help for the visual detection of tetracycline residues.

Advances in Biosignal Sensing and Signal Processing Methods with Wearable Devices

AbstractWearable devices have received significant attention recently for their ability to monitor critical physiological signals noninvasively, such as electrocardiography, electroencephalography, electromyography, and photoplethysmography. These bio‐integrated wearable systems can potentially fill gaps in conventional clinical practice by providing highly cost‐effective health characterization and portable continuous health monitoring. Further, the physiological signals measured by wearables require post‐processing to derive meaningful values, such as heart rate or blood oxygen saturation. This requirement, in conjunction with the smaller form factor and limited sensor count of the miniaturized systems, often necessitates robust signal processing and data analysis to approach the stringent performance specifications of conventional medical devices, and machine learning techniques have found success in filling this analytical role for their ability to learn complex functional relationships. Thus, this review outlines a systematic summary of the latest research on various wearable devices and their biosignal sensing and signal processing methods, emphasizing machine learning. We also discuss the developmental challenges and advantages of current machine‐learning methods, while suggesting research directions for future studies.

Estimation of radon in groundwater and analysis of radon and thoron exhalation rates of the soil in Mokokchung district, Nagaland, India

The present study of the analysis of radon in groundwater and its exhalation rates in soil was carried out in 19 selected locations in Mokokchung district, Nagaland, India. The survey was carried out by employing a portable scintillation-based smart RnDuo monitor. The radon (222Rn) mass exhalation rates of the soil were found to vary from 27 mBqKg−1h−1 to 40 mBqKg−1h−1 with an average of 31 ± 0.8 mBqKg−1h−1. While the thoron (220Rn) surface exhalation rate of the soil was found to vary from 714.6 Bqm−2h−1 to 2166.6 Bqm−2h−1 with an average of 1009.9 ± 77.1 Bqm−2h−1. The radon (222Rn) in drinking water was found to vary from 1.48 BqL−1 to 2.22 BqL−1 with an average of 1.82 ± 0.04 BqL−1 and is below the world average values as set by USEPA (1991), WHO (2004) and UNSCEAR (2008). Furthermore, the total effective dose range is below the WHO (2003) recommendation.

P061 RAPID-OSA Study: Remote ApneaLink Providing Immediate Diagnosis of Obstructive Sleep Apnoea

Abstract Introduction In-laboratory polysomnography (PSG) is the gold standard for diagnosis of obstructive sleep apnea. However, studies showed portable sleep monitoring devices can reliably substitute PSG in patients with a high pre-test probability of moderate-to-severe OSA. In this prospective study, we assessed utility of ApneaLink for diagnosis of OSA in patients living in rural and remote QLD. Method Thirty-five patients, living in rural and remote QLD were included in the study. ApneaLink device with clear instructions was sent to patients via registered post for being worn for a single typical night. Results were analysed and patients were reviewed post study. Progress to date The study population included thirty five patients (58.8%) male with a mean age of 53.2 years old and median body mass index of 36 kg/m2. The mean time between receiving referral to concluding ApneaLink study was 56 days. This is statistically significant compared to our previous experience in 2017 with mean wait time of 153 days for in-laboratory sleep study (p-value 0.0001). There was significant reduction in expenses in patients underwent level three sleep study compared to PSG. Total postage cost of our study was 1107 Aud with each AL device price of 350$ while in-laboratory study costs 2338$ per night. Conclusion AL has shown substantial cost effectiveness in diagnosis of OSA in patients with uncomplicated moderate to high pre-test probability by eliminating travel cost and reducing in-laboratory sleep study requirement. Full results to follow.

O040 Associations between Sleep Irregularity and Hypertension: Sleep Sensor Data from Over Two Million Nights

Abstract Introduction Irregular sleep has been associated with worse cardio-metabolic health compared to regular sleep, but prior studies are limited in sample size and have assessed sleep irregularity over short assessment periods (7-14 days). This study investigated associations between sleep irregularity and hypertension in a large, global sample over multiple months. Methods Data from 12,300 participants (Mean ± SD; 50 ± 12 years, 12% females) who used an under-mattress sleep device and a portable blood pressure monitor between July 2020 and March 2021 were included. Each participant had ~180 nights of recordings and ~70 blood pressure entries. Sleep duration regularity was assessed as the standard deviation of device-assessed total sleep time. Sleep timing regularity was assessed as the standard deviation of sleep onset time and sleep midpoint. Logistic regressions were conducted, controlling for age, sex, BMI, and mean total sleep time. Results Across total sleep time quartiles, sleep duration irregularity was consistently associated with a 9-15% increase in hypertension risk. A 38-minute increase in sleep midpoint irregularity was associated with an 11% (1.11 [1.03, 1.20]) increase in hypertension risk, independent of mean total sleep time and mean sleep midpoint. Similarly, a ~31-minute increase in sleep onset time irregularity was associated with a 29% increased risk of hypertension (1.29 [1.18, 1.42]). Conclusions Irregular sleep, regardless of average total sleep time, was associated with increased hypertension risk. Further assessment of day-to-day fluctuations in sleep duration and timing for potential effects on next-day blood pressure and cardiovascular health outcomes is warranted.

Ceria and gold co-decorated porous MoS2@graphene nanocomposite electrochemical electrode integrated with smartphone-controlled microstation for simultaneous dual metal ions detection

Continuous increase in release of toxic metals into ecosystem posed a threat to public ecology, leading to demand for the portable monitoring system to control contamination source and monitor disease progression. Herein, ceria and gold co-decorated porous MoS2@graphene nanocomposite was synthesized to construct electrochemical chip and integrate with smartphone-controlled hand-held microstation for simultaneous detecting Zn(II) and Cu(II). Concretely, MoS2 nanosheets coated polyimide were firstly laser-induced into 3D frame-structured MoS2/graphene with abundant oxygen-containing groups and active breaking edges, thereby accelerating the electron transfer and improving the absorptivity and reductive affinity for divalent ions. Double electro-deposition of ceria and gold provide vast oxygen vacancies for sensing, and Ce(III)/Ce(IV) cycle inhibit the recombination of electrons and holes, prolonging the life of carriers to enhance its electro-conductibility. The hydroxylation of ceria under acidic conditions is favorable for ions adsorption. Benefitting from synergetic effect among materials, the smartphone-controlled sensing system exhibits high sensitivity and low detection limit for Cu(II) of 2.8 ppt and Zn(II) of 103.6 ppt. Low energy barrier of target plating/stripping kinetics were also substantiated via calculating activation energy upon composite using Arrhenius formula. Furthermore, its outstanding flexibility, reusability, and anti-interference performance was verified, indicating the potential implementation possibilities in complex environment.

Surface-enhanced Raman scattering as a potential strategy for wearable flexible sensing and point-of-care testing non-invasive medical diagnosis.

As a powerful and effective analytical tool, surface-enhanced Raman scattering (SERS) has attracted considerable research interest in the fields of wearable flexible sensing and non-invasive point-of-care testing (POCT) medical diagnosis. In this mini-review, we briefly summarize the design strategy, the development progress of wearable SERS sensors and its applications in this field. We present SERS substrate analysis of material design requirements for wearable sensors and highlight the benefits of novel plasmonic particle-in-cavity (PIC)-based nanostructures for flexible SERS sensors, as well as the unique interfacial adhesion effect and excellent mechanical properties of natural silk fibroin (SF) derived from natural cocoons, indicating promising futures for applications in the field of flexible electronic, optical, and electrical sensors. Additionally, SERS wearable sensors have shown great potential in the fields of different disease markers as well as in the diagnosis testing for COVID-19. Finally, the current challenges in this field are pointed out, as well as the promising prospects of combining SERS wearable sensors with other portable health monitoring systems for POCT medical diagnosis in the future.

A benzothiazole-based fluorescent probe for sensing Zn2+ and its application

A novel probe L based on benzothiazole was synthesized and characterized. The sensing performance was investigated by fluorescence spectrometry. The results showed that probe L had a single selective recognition towards Zn2+ with a low detection limit (0.678 μM) in DMSO/Tris-HCl buffer solution. The binding ratios between L and Zn2+ were 1: 1. The pH test showed that L had a wide detection range of 7–10 for Zn2+. Probe L responds very fast to Zn2+ about 30 s. The recognition mechanism was studied by 1H NMR, mass spectrum analysis and theoretical calculations. The test strips and fluorescence film experiments of the probe show that probe L can detect liquid and solid zinc salts, revealing that the probe is expected to be used for portable visual real-time monitoring of liquid and solid zinc salts. Notably, probe L was successfully applied in different water samples and living Hela cells for the determination and imaging of Zn2+ respectively.