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1.
J Family Community Med ; 31(2): 99-106, 2024.
Article in English | MEDLINE | ID: mdl-38800794

ABSTRACT

BACKGROUND: Cognitive decline affects the quality of life, and dementia affects independence in daily life activities. Multimorbidity in older adults is associated with a higher risk of cognitive impairment. This research aims to study the relationship between cognitive decline and multimorbidity in the elderly population in the Eastern Province, Saudi Arabia. MATERIALS AND METHODS: This cross-sectional research was conducted from July to October 2022 among adults over 60 years. All patients with two or more comorbidities were contacted for a face-to-face interview and cognitive testing to estimate cognitive function by trained family physicians using St. Louis University Mental State Examination. ANOVA and Chi-square test were used to test for statistical significance. Binary logistic regression was used to show the odds of having cognitive impairment and multimorbidity. All tests were performed at 5% level of significance. RESULTS: The study involved 343 individuals; majority (74.1%) aged 60-75 years and were males (67.9%). Hypertension, diabetes, and chronic pain were reported by 56%, 48%, and 44% participants, respectively. Thirty percent participants had 3 or more comorbidities. About 36% had mild neurocognitive disorder and 31.2% had dementia. The results showed that age, gender (female), diabetes, stroke, chronic pain, and multimorbidity were significantly associated with cognitive impairment. In our study, hypertension, coronary artery diseases, depression, and anxiety were not significantly associated with risk of cognitive decline. CONCLUSION: Our study found that multimorbidity is significantly associated with cognitive decline. Controlling comorbidities and preventing risk factors in midlife could help in delaying the progression of the disease.

2.
Front Comput Neurosci ; 18: 1307305, 2024.
Article in English | MEDLINE | ID: mdl-38444404

ABSTRACT

Introduction: Dementia is one of the major global health issues among the aging population, characterized clinically by a progressive decline in higher cognitive functions. This paper aims to apply various artificial intelligence (AI) approaches to detect patients with mild cognitive impairment (MCI) or dementia accurately. Methods: Quantitative research was conducted to address the objective of this study using randomly selected 343 Saudi patients. The Chi-square test was conducted to determine the association of the patient's cognitive function with various features, including demographical and medical history. Two widely used AI algorithms, logistic regression and support vector machine (SVM), were used for detecting cognitive decline. This study also assessed patients' cognitive function based on gender and developed the predicting models for males and females separately. Results: Fifty four percent of patients have normal cognitive function, 34% have MCI, and 12% have dementia. The prediction accuracies for all the developed models are greater than 71%, indicating good prediction capability. However, the developed SVM models performed the best, with an accuracy of 93.3% for all patients, 94.4% for males only, and 95.5% for females only. The top 10 significant predictors based on the developed SVM model are education, bedtime, taking pills for chronic pain, diabetes, stroke, gender, chronic pains, coronary artery diseases, and wake-up time. Conclusion: The results of this study emphasize the higher accuracy and reliability of the proposed methods in cognitive decline prediction that health practitioners can use for the early detection of dementia. This research can also stipulate substantial direction and supportive intuitions for scholars to enhance their understanding of crucial research, emerging trends, and new developments in future cognitive decline studies.

3.
Med Arch ; 78(1): 51-54, 2024.
Article in English | MEDLINE | ID: mdl-38481585

ABSTRACT

Background: The association between obstructive sleep apnea (OSA) and cognitive decline among older adults is a still a topic of debate. Objective: The aim of this study was to determine the association between risk of OSA and cognitive function among Saudi older adults. Methods: This was a cross-sectional community-based study conducted between July and October 2022. Participants were recruited from gathering areas where older adults are likely attending such as district centers, waiting areas of shopping malls, and mosques. Questionnaires were completed using face-to-face interviews. The questionnaire included questions of sociodemographics, sleep pattern and health status. A validated Arabic version of Athens insomnia scale, STOP-BANG questionnaire, and St. Louis University mental status (SLUMS) questionnaire were used. A multi-Linear regression model was used to determine the association between cognitive functions and OSA. Results: A total of 343 participants were recruited in this study, of which 86% were male. The mean age was 65±9 years. 65% of participants with high risk of sleep apnea were diagnosed with either dementia or mild cognitive impairment (MCI). Most of the participants who were illiterate (83%) had dementia, while only 4% of participants with higher education had dementia. Conclusion: Dementia and mild cognitive impairment is prevalent among Saudi older adults with high risk of OSA. Clinicians and patients should be aware of the risk of developing dementia in patients with OSA, especially if remain untreated.


Subject(s)
Cognitive Dysfunction , Dementia , Sleep Apnea, Obstructive , Humans , Male , Aged , Middle Aged , Female , Cross-Sectional Studies , Saudi Arabia/epidemiology , Surveys and Questionnaires , Cognition , Cognitive Dysfunction/epidemiology , Cognitive Dysfunction/etiology , Sleep Apnea, Obstructive/complications , Sleep Apnea, Obstructive/epidemiology
4.
Nat Sci Sleep ; 16: 53-62, 2024.
Article in English | MEDLINE | ID: mdl-38322016

ABSTRACT

Introduction: Sleepy driving is associated with Motor Vehicles Accidents (MVAs). In Saudi Arabia, previous studies have addressed this association among men only. Therefore, the aim of this study was to compare the prevalence of sleepy driving and associated factors between genders. Methods: In a cross-sectional study design, we offered a self-administered online questionnaire to 3272 participants from different regions of Saudi Arabia. The questionnaire included 46 questions covering sociodemographics, driving habits, sleeping habits, Epworth Sleepiness Scale, and Berlin questionnaire to assess the risk of sleep apnea. Univariable and multivariable logistic regression analyses were used to determine the significant factors associated with self-reported sleepy driving, defined as operating a motor vehicle while feeling sleepy in the preceding six months. Results: Of the 3272 invitees, 2958 (90%) completed the questionnaire, of which 1414 (48%) were women. The prevalence of sleepy driving in the preceding six months was 42% (men: 50% and women 32%, p<0.001). Specifically, participants reported the following: 12% had had to stop their vehicle due to sleepiness (men: 16.2% and women 7%, p<0.001), 12.4% reported near-miss accidents (men: 16.2% and women: 8.2%, p<0.001) and 4.2% reported an accident due to sleepiness (men: 4.3% and women: 4%, p=0.645). In multivariable analysis, being male, younger age, use of any type of medications, shift working, working more than 12 hours per day, driving duration of 3-5 hours per day, driving experience of more than 2 years, excessive daytime sleepiness and risk of having obstructive sleep apnea were all associated with increased likelihood of falling asleep while driving in the preceding 6 months. Conclusion: Sleepy driving and MVA are prevalent in both gender but was higher in men. Future public health initiatives should particularly focus on men, since men reported a greater likelihood of both sleep-related MVA and "near miss" events.

5.
J Med Life ; 16(1): 101-109, 2023 Jan.
Article in English | MEDLINE | ID: mdl-36873126

ABSTRACT

This study aimed to measure the level of vaccine hesitancy among the Saudi population using the WHO Vaccine Hesitancy Scale (VHS). A cross-sectional study using a modified vaccine hesitancy scale (VHS) was conducted among Saudi Arabian residents between April 4 and May 24, 2021. The relationship between participants' willingness to uptake COVID-19 vaccines and their demographics, awareness of COVID-19, and health status was evaluated. The chi-square test was employed to compare categorical variables and logistic regression for the associations of demographical characteristics with acceptance of the vaccine. We received a total of 1657 completed responses. 1,126 participants (68%) were vaccinated, of which 19% were vaccinated with one dose only, and 49% were fully vaccinated (with two doses). Safety concerns and worries about side effects were higher among the hesitant group (p<0.001). 96% of the participants from the willing group were not hesitant to have the vaccine, whereas in the same group, 70% thought they had good health and the vaccine was not needed. Logistic regression analysis revealed that participants with chronic diseases had lower odds of being willing to be vaccinated (OR=0.583, p-value 0.04). The study findings suggest key factors associated with COVID-19 vaccine hesitancy in the Saudi population and can help public health authorities plan strategies to minimize vaccine hesitancy and improve awareness about vaccine acceptance.


Subject(s)
COVID-19 Vaccines , COVID-19 , Humans , Saudi Arabia , Cross-Sectional Studies , Health Status
6.
Acta Biomed ; 93(5): e2022245, 2022 10 26.
Article in English | MEDLINE | ID: mdl-36300232

ABSTRACT

BACKGROUND AND AIM: Highly competitive and demanding environments in educational institutions led to reduced sleep time for both students and faculty globally. The primary objective of this study was to determine the duration and quality of sleep among students and faculty of Imam Abdulrahman Bin Faisal University (IAU). The secondary objective was to explore the relationship between depression and sleep duration and quality among students and faculty. METHODS: The study was conducted during 2021 in Dammam, Saudi Arabia. An online survey was disseminated among the university students. The survey form included: demographic data, Patient Health Questionnaire (PHQ9), Pittsburg Sleep Quality Index (PSQI) and Epworth Sleepiness scale (ESS). The responses were analyzed using bivariate and multivariate analysis. RESULTS: A total of 509 responses satisfying the inclusion criteria were included (323 student and 186 faculty). The average sleep duration for the entire cohort was 6.21 ± 1.32 hours, with 6.5% sleeping less than 5 hours per night. The mean PSQI score was 7.61 ± 3.09, with 73.1% falling in the poor sleep quality category (PSQI score >5). The mean PHQ9 score was 8.86 ± 6.20, with 63.9% falling in the  mild depression category. The mean ESS score was 6.59 ± 4.02, with 11% having a score >10 (corresponding to excessive daytime sleepiness). CONCLUSIONS: A significant proportion of surveyed students and faculty IAU suffer from sleep insufficiency, poor sleep quality, and mild degree of depression. Initiatives to tackle the issue of poor sleep quality and quantity among university students and faculty are required.


Subject(s)
Depression , Sleep , Humans , Universities , Depression/epidemiology , Students , Surveys and Questionnaires , Faculty
7.
Front Neurosci ; 16: 917987, 2022.
Article in English | MEDLINE | ID: mdl-35720687

ABSTRACT

Purpose: Current evidence of whether napping promotes or declines cognitive functions among older adults is contradictory. The aim of this study was to determine the association between nap duration and cognitive functions among Saudi older adults. Methods: Old adults (> 60 years) were identified from the Covid-19 vaccine center at Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia between May and August 2021. Face-to-face interviews were conducted by a geriatrician or family physicians. Data collected for each participant included sociodemographic, sleep patterns, health status and cognitive functions. St. Louis University mental status (SLUMS) was used to assess the cognitive functions. A multi-Linear regression model was used to determine the association between cognitive functions and nap duration. Results: Two-hundred participants (58 females) aged 66 ± 5 years were recruited. Participants were categorized according to their nap duration into non-nappers (0 min), short nappers (> 0- ≤ 30 min), moderate nappers (> 30-≤ 90 min), and extended nappers (> 90 min). The mean duration of the nap was 49.1 ± 58.4 min. The mean SLUMS score was 24.1 ± 4.7 units. Using the multi-linear regression model, the mean total SLUMS score for extended nappers was, on average, significantly lower than non-nappers [-2.16 units; 95% CI (-3.66, -0.66), p = < 0.01] after controlling for the covariates (age, sex, education level, sleep hours, diabetes mellitus, hypertension, pain). Conclusions: Extended napping was associated with deterioration in cognitive function among Saudi older adults.

8.
Biosensors (Basel) ; 12(1)2022 Jan 13.
Article in English | MEDLINE | ID: mdl-35049668

ABSTRACT

Measuring pH has become a major key for determining health conditions, and food safety. The traditional pH assessment approaches are costly and offer low sensitivity. Here, a novel pH sensor based on a pH-responsive hydrogel has been developed. A Fresnel lens pattern was replicated on the surface of the pH-responsive hydrogel using the replica mould method. The pH sensors were tested in a pH range of 4-7. Introducing various pH solutions to the pH sensor led to volumetric shifts as the hydrogel swelled with pH. Consequently, the dimensions of the replicated Fresnel lens changed, modifying the focal length and the focus efficiency of the optical sensor. As a result, the measured optical power at a fixed distance from the sensor changed with pH. The optical sensor showed the best performance in the acidic region when pH changed from 4.5 to 5.5, in which the recorded power increased by 13%. The sensor exhibited high sensitivity to pH changes with a short respond time in a reversible manner. The developed pH optical sensor may have applications in medical point-of-care diagnostics and wearable continuous pH detection devices.


Subject(s)
Hydrogels , Wearable Electronic Devices , Hydrogen-Ion Concentration
9.
F1000Res ; 11: 24, 2022.
Article in English | MEDLINE | ID: mdl-37360937

ABSTRACT

BACKGROUND: The coronavirus disease 2019 (COVID-19) pandemic is a major public health crisis worldwide. In less than 12 months since the World Health Organization declared the outbreak, several different COVID-19 vaccines have been approved and deployed mostly in developed countries since January 2021. However, hesitancy to accept the newly developed vaccines is a well-known public health challenge that needs to be addressed. The aim of this study was to measure willingness and hesitancy toward COVID-19 vaccines among health care practitioners' (HCPs) in Saudi Arabia.   Methods: A cross-sectional study using an online self-reported survey was conducted among HCPs in Saudi Arabia between April 4th to April 25th 2021 using snowball sampling. Multivariate logistic regression was employed to identify the possible factors affecting HCPs' willingness and hesitancy to receive COVID-19 vaccines.   Results: Out of 776 participants who started the survey, 505 (65%) completed it and were included in the results. Among all HCPs, 47 (9.3%) either said "no" to receive the vaccine [20 (4%)] or were hesitant to receive it [27 (5.3%)]. Of the total number of the HCPs, 376 (74.5%) already received the COVID-19 vaccine, and 48 (9.50%) were registered to receive it. The main reason of agreement to receive the COVID-19 vaccine was "wanting to protect self and others from getting the infection" (24%).   Conclusion: Our findings have shown that hesitancy toward receiving COVID-19 vaccines among HCPs in Saudi Arabia is limited and therefore may not be a serious issue. The outcomes of this study may help to understand factors that lead to vaccine hesitancy in Saudi Arabia and help public health authorities to design targeted health education interventions aiming to increase uptake of these vaccines.


Subject(s)
COVID-19 Vaccines , COVID-19 , Humans , COVID-19 Vaccines/therapeutic use , Cross-Sectional Studies , Saudi Arabia/epidemiology , COVID-19/epidemiology , COVID-19/prevention & control , Self Report
10.
Front Endocrinol (Lausanne) ; 13: 1020617, 2022.
Article in English | MEDLINE | ID: mdl-36743921

ABSTRACT

Background: Obstructive sleep apnea (OSA) is a prevalent disease that is associated with an increased incidence of type II diabetes mellitus (DM) if left untreated. We aimed to determine the association between glycosylated hemoglobin (HbA1c) levels and both nocturnal hypoxemia and apnea-hypopnea index (AHI) among a Saudi patients with OSA. Methods: A cross-sectional study that enrolled 103 adult patients diagnosed with DM and confirmed to have OSA by full night attended polysomnography between 2018 and 2021. Those who presented with acute illness, chronic obstructive pulmonary disease (COPD)/restrictive lung diseases causing sleep-related hypoxemia, or no available HbA1c level within 6 months before polysomnography were excluded from the study. Univariate and multivariate linear regression analyses between HbA1c levels and parameters of interest were tested. Results: Sixty-seven (65%) of the studied population had uncontrolled DM (HbA1c ≥7%). In univariate regression analysis, there was a significant positive association between HbA1c, and sleep time spent with an oxygen saturation below 90% (T90), female gender, and body mass index (BMI) (p<0.05) but not AHI, or associated comorbidities (p>0.05). In the multivariate analysis, HbA1c was positively associated with increasing T90 (p<0.05), and ODI (p<0.05), but not with AHI (p>0.05). Conclusion: Nocturnal hypoxemia could be an important factor affecting glycemic control in patients with OSA suffering from DM irrespective of the severity of both diseases.


Subject(s)
Diabetes Mellitus, Type 2 , Sleep Apnea, Obstructive , Adult , Humans , Female , Diabetes Mellitus, Type 2/complications , Diabetes Mellitus, Type 2/epidemiology , Glycated Hemoglobin , Cross-Sectional Studies , Glycemic Control , Saudi Arabia/epidemiology , Sleep Apnea, Obstructive/complications , Sleep Apnea, Obstructive/epidemiology , Sleep Apnea, Obstructive/therapy , Hypoxia/etiology
11.
Ann Thorac Med ; 16(2): 141-147, 2021.
Article in English | MEDLINE | ID: mdl-34012480

ABSTRACT

MOTIVATION: Studies have shown poor clinical effectiveness of the Epworth Sleepiness Scale (ESS) due to its ambiguity of items and cultural applicability. This study aimed to investigate the efficacy of a Visual Analog Scale (VAS) to assess sleepiness, compared to ESS. METHODS: Thirty-two obstructive sleep apnea (OSA) patients and 32 healthy participants completed two visits, 1 month apart, during which they completed both ESS and VAS. Patients diagnosed with OSA were treated with Continuous positive airway pressure (CPAP) between visits. The agreement between the ESS and VAS scores in both patients with OSA and healthy participants was investigated using Pearson correlation and Area Under the receiver operating characteristics. RESULTS: The (mean ± standard deviation) Oxygen Desaturation Index for patients with OSA was 18.5 ± 5.7 events/hour and 1.7 ± 1.0 events/hour in the healthy participants. A reduction in sleepiness, following CPAP treatment occurred in patients with OSA, using the ESS (11.2 ± 5.5-4.7 ± 5.0 points, P < 0.001) and the VAS (50.2 ± 3.0-21.9 ± 26.5 mm, P < 0.001). There was no significant change in sleepiness, in healthy participants using the ESS (3.91 ± 3.14-3.34 ± 3.27 points (P < 0.48) or the VAS (15.58 ± 21.21-12.05 ± 14.75 mm, (P < 0.44). A Likert scale showed that the VAS was easier to use compared to ESS in visit 1 (VAS: 8.7 ± 1.9 points, ESS: 7.7 ± 2.6 points, (P < 0.001), and visit 2 (VAS: 9.5 ± 1.4 points, ESS: 8.6 ± 1.5 points, P < 0.001). CONCLUSION: These preliminary results suggest that the VAS can detect a change in sleepiness after CPAP treatment in patients with OSA and that the VAS was also easier to use compared to ESS.

12.
Nat Sci Sleep ; 12: 661-669, 2020.
Article in English | MEDLINE | ID: mdl-33061723

ABSTRACT

BACKGROUND AND OBJECTIVES: Changes in autonomic cardiac activity during night sleep are well documented. However, there is limited information regarding changes in the autonomic cardiac profile during daytime naps. Heart rate variability (HRV) and baroreflex sensitivity (BRS) are reliable measures of autonomic cardiac activity. The purpose of this study was to determine the changes in HRV and BRS during daytime naps in healthy men. METHODS: This was a cross-sectional study of 25 healthy men. Polysomnographic recording with electrocardiogram monitoring was conducted for all volunteers during a 50-80 min nap between 3.30 pm and 5.30 pm. Five-minute segments during pre-nap wakefulness, non-rapid eye movement (NREM) sleep stages (N1, N2, and N3), rapid eye movement (REM) sleep stage, and post-nap wakefulness were used to measure changes in the variation in HRV parameters, including inter-beat interval (RR-interval), total spectral power (TP), high-frequency power (HF), low-frequency power (LF), and low frequency/high-frequency ratio (LF/HF). BRS was also measured for 10 min during pre- and post-nap wakefulness using finger arterial pressure measurement (Finometer Pro ®). RESULTS: HRV increased significantly during NREM sleep compared with that during pre-nap wakefulness (p < 0.05), as reflected by RR-interval prolongation, higher HF, and increased HFnu (normalized units). Furthermore, there was a parallel reduction in TP, LF, and LF/HF ratio during NREM sleep, indicating parasympathetic predominance over cardiac autonomic activity. HF and HFnu were significantly reduced during REM sleep compared with that during NREM sleep (p < 0.05). BRS did not show significant differences between pre- and post-nap wakefulness. CONCLUSION: We observed a progressive increase in parasympathetic activity during daytime sleep as NREM sleep deepened compared with that during wakefulness and REM sleep. Daytime nap may have a favorable cardiovascular impact.

13.
IEEE Trans Biomed Eng ; 67(1): 203-212, 2020 01.
Article in English | MEDLINE | ID: mdl-31021747

ABSTRACT

OBJECTIVE: Advances in sensor miniaturization and computational power have served as enabling technologies for monitoring human physiological conditions in real-world scenarios. Sleep disruption may impact neural function, and can be a symptom of both physical and mental disorders. This study proposes wearable in-ear electroencephalography (ear-EEG) for overnight sleep monitoring as a 24/7 continuous and unobtrusive technology for sleep quality assessment in the community. METHODS: A total of 22 healthy participants took part in overnight sleep monitoring with simultaneous ear-EEG and conventional full polysomnography recordings. The ear-EEG data were analyzed in the both structural complexity and spectral domains. The extracted features were used for automatic sleep stage prediction through supervized machine learning, whereby the PSG data were manually scored by a sleep clinician. RESULTS: The agreement between automatic sleep stage prediction based on ear-EEG from a single in-ear sensor and the hypnogram based on the full PSG was 74.1% in the accuracy over five sleep stage classification. This is supported by a substantial agreement in the kappa metric (0.61). CONCLUSION: The in-ear sensor is feasible for monitoring overnight sleep outside the sleep laboratory and also mitigates technical difficulties associated with PSG. It, therefore, represents a 24/7 continuously wearable alternative to conventional cumbersome and expensive sleep monitoring. SIGNIFICANCE: The "standardized" one-size-fits-all viscoelastic in-ear sensor is a next generation solution to monitor sleep-this technology promises to be a viable method for readily wearable sleep monitoring in the community, a key to affordable healthcare and future eHealth.


Subject(s)
Electroencephalography/instrumentation , Electroencephalography/methods , Polysomnography/methods , Wearable Electronic Devices , Adult , Ear/physiology , Electrodes , Equipment Design , Humans , Signal Processing, Computer-Assisted , Sleep Stages/physiology , Young Adult
14.
Nat Sci Sleep ; 10: 385-396, 2018.
Article in English | MEDLINE | ID: mdl-30538591

ABSTRACT

OBJECTIVES: Detecting sleep latency during the Multiple Sleep Latency Test (MSLT) using electroencephalogram (scalp-EEG) is time-consuming. The aim of this study was to evaluate the efficacy of a novel in-ear sensor (in-ear EEG) to detect the sleep latency, compared to scalp-EEG, during MSLT in healthy adults, with and without sleep restriction. METHODS: We recruited 25 healthy adults (28.5±5.3 years) who participated in two MSLTs with simultaneous recording of scalp and in-ear EEG. Each test followed a randomly assigned sleep restriction (≤5 hours sleep) or usual night sleep (≥7 hours sleep). Reaction time and Stroop test were used to assess the functional impact of the sleep restriction. The EEGs were scored blind to the mode of measurement and study conditions, using American Academy of Sleep Medicine 2012 criteria. The Agreement between the scalp and in-ear EEG was assessed using Bland-Altman analysis. RESULTS: Technically acceptable data were obtained from 23 adults during 69 out of 92 naps in the sleep restriction condition and 25 adults during 85 out of 100 naps in the usual night sleep. Meaningful sleep restrictions were confirmed by an increase in the reaction time (mean ± SD: 238±30 ms vs 228±27 ms; P=0.045). In the sleep restriction condition, the in-ear EEG exhibited a sensitivity of 0.93 and specificity of 0.80 for detecting sleep latency, with a substantial agreement (κ=0.71), whereas after the usual night's sleep, the in-ear EEG exhibited a sensitivity of 0.91 and specificity of 0.89, again with a substantial agreement (κ=0.79). CONCLUSION: The in-ear sensor was able to detect reduced sleep latency following sleep restriction, which was sufficient to impair both the reaction time and cognitive function. Substantial agreement was observed between the scalp and in-ear EEG when measuring sleep latency. This new in-ear EEG technology is shown to have a significant value as a convenient measure for sleep latency.

15.
RSC Adv ; 7(85): 53916-53924, 2017 Nov 25.
Article in English | MEDLINE | ID: mdl-29308195

ABSTRACT

Continuous glucose monitoring aims to achieve accurate control of blood glucose concentration to prevent hypo/hyperglycaemia in diabetic patients. Hydrogel-based systems have emerged as a reusable sensing platform to quantify biomarkers in high-risk patients at clinical and point-of-care settings. The capability to integrate hydrogel-based systems with optical transducers will provide quantitative and colorimetric measurements via spectrophotometric analyses of biomarkers. Here, we created an imprinting method to rapidly produce 2.5D photonic concavities in phenylboronic acid functionalized hydrogel films. Our method exploited diffraction properties of hexagonally-packed 2.5D photonic microscale concavities having a lattice spacing of 3.3 µm. Illumination of the 2.5D hexagonally-packed structure with a monochromatic light source in transmission mode allowed reversible and quantitative measurements of variation in the glucose concentration based on first order lattice interspace tracking. Reversible covalent phenylboronic acid coupling with cis-diols of glucose molecules expanded the hydrogel matrix by ∼2% and 34% in the presence of glucose concentrations of 1 mM and 200 mM, respectively. A Donnan osmotic pressure induced volumetric expansion of the hydrogel matrix due to increasing glucose concentrations (1-200 mM), resulted in a nanoscale modulation of the lattice interspace, and shifted the diffraction angle (∼45° to 36°) as well as the interspacing between the 1st order diffraction spots (∼8 to 3 mm). The sensor exhibited a maximum lattice spacing diffraction shift within a response time of 15 min in a reversible manner. The developed 2.5D photonic sensors may have application in medical point-of-care diagnostics, implantable chips, and wearable continuous glucose monitoring devices.

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