[This corrects the article DOI: 10.7759/cureus.44145.].
PURPOSE: To study the outcomes of diode laser transscleral cyclophotocoagulation (TSCPC) with trans-corneal transillumination using a novel low-cost torchlight method in refractory glaucoma. METHODS AND ANALYSIS: This prospective interventional study included patients with refractory glaucoma who underwent TSCPC with trans-corneal transillumination (TSCPC-TI) using a novel low-cost torchlight method. Patients completing a minimum 6-month follow-up were analyzed. They were compared to a historical control group of patients who underwent TSCPC without transillumination (TSCPC-No TI) at 6-month follow-up period. We analyzed the mean laser energy delivered, post-laser intraocular pressure (IOP) reduction, number of antiglaucoma medications (AGM), the requirement of retreatment and complications of the procedure in both groups. RESULTS: 32 eyes of 29 patients comprised the TSCPC-TI group and were compared with 39 eyes of 37 patients in the TSCPC-No TI group. The TSCPC-TI group required lower energy than the TSCPC-No TI group (46.15 ± 22.8 Vs 80.65 ± 56.1 J p < 0.001). At 6-month follow-up, the TSCPC-TI group required lesser AGM for IOP control (2.33 ± 1.02 vs 3.02 ± 1.32 p = 0.01). There was a significantly reduced dependence of oral acetazolamide in the TSCPC-TI group at 6 months follow-up (15.6% vs 41% p = 0.03%). The success and response rates were 71.8% Vs 23.1%; p < 0.0001 and 87.5% Vs 51.2%; p = 0.001 significantly high in the TSCPC-TI group. The TSCPC-No TI group had a significantly high failure rate (12.5% Vs 48.2% p = 0.001). Hypotony (n = 1) and phthisis (n = 2) were noted TSCPC-No TI group. CONCLUSIONS: TSCPC with transillumination with a low-cost torchlight resulted in a more efficient and effective cycloablation than TSCPC without transillumination.
PURPOSE: To study the ophthalmologic manifestations of systemic sclerosis (SSc) and its correlation with autoantibody profile. METHODS: A cross-sectional study on 200 eyes of 100 consecutive adult patients diagnosed with SSc was performed at a tertiary care center in Northern India. The examination of ocular adnexa, anterior segment, and posterior segment with slit-lamp biomicroscopy, tear film break-up time (TBUT), Schirmer's II test, and choroidal thickness measurement by swept-source ocular coherence tomography was done. Autoantibody profile was available for 85 patients, and its statistical association with the ocular examination findings was analyzed. RESULTS: In total, 100 patients (93 females and 7 males) were included. The mean age was 45.11 ± 11.68 years, and the mean disease duration was 6.93 ± 3.68 years. Meibomian gland disease was more commonly found in patients with the diffuse subtype of SSc (P = 0.037). Choroidal thickness was increased in 34% and decreased in 7% (reference range = 307 ± 79 mm) patients. Reduced TBUT, meibomian gland dysfunction, and eyelid stiffness had a statistically significant association with the presence of anti-Scl-70 antibody (P = 0.003, <0.0001, and 0.004, respectively). These patients had ocular fatigue, foreign body sensation, and burning sensation. No significant association was noted with the presence of SS-A/Ro and SS-B/La antibodies. CONCLUSION: This study highlights the need for an active comprehensive ophthalmic evaluation. Approximately 75% of the patients in our cohort had ocular involvement to varying extent. An isolated presence of anti-Scl70 antibody was also found to have a positive association with dry eye disease.
Organophosphates pesticide (OP) toxicity through water resources is a large concern globally among all the emerging pollutants. Detection of OPs is a challenge which needs to be addressed considering the hazardous effects on the health of human beings. In the current research thin film biosensors of recombinant, Organophosphorus acid anhydrolase (OPAA) enzyme along with carbon quantum dots (CQDs) immobilized in thin films were developed. OPAA-CQDs thin film biosensors were used for the specific detection of two OPs Ethyl Paraoxon (EP) and Methyl Parathion (MP) in river water and household water supply. Recombinant OPAA enzyme was expressed in E. Coli, purified and immobilized on the CQD containing chitosan thin films. The CQDs used for this purpose were developed by a one-pot hydrothermal method from phthalic acid and Tri ethylene diamine. The properties of CQDs, OPAA and thin films were characterized using techniques like XPS, TEM, XRD, enzyme activity and CLSM measurements. Biosensing studies of EP and MP were performed by taking fluorescence measurements using a fiber optic spectrometer. The analytical parameters of biosensing were compared against an estimation carried out using the HPLC method. The biosensing performance indicates that the OPAA-CQDs thin film-based biosensors were able to detect both EP and MP in a range of 0-100 µM having a detection limit of 0.18 ppm/0.69 ppm for EP/MP, respectively with a response time of 5 min. The accuracy of estimation of EP/MP when spiked in water resources lie in the range of â¼100-102% which clearly indicates the OPAA-CQD based thin film biosensors can function as a point-of-use method for the detection of OP pesticides in complex water resources.
Biosensing Techniques , Methyl Parathion , Parathion , Pesticides , Quantum Dots , Humans , Paraoxon , Aryldialkylphosphatase , Carbon , Water Resources , Escherichia coli , Pesticides/analysis , Biosensing Techniques/methods
PRCIS: Trans-corneal transillumination (TI) aided transscleral cyclophotocoagulation (TSCPC) for intraocular pressure control of refractory pediatric glaucoma was found to be effective at 1 year. PURPOSE: To study 1-year outcomes of diode laser TSCPC with trans-corneal TI using a novel low-cost torchlight method in refractory pediatric glaucoma. METHODS: This prospective interventional study included children with refractory glaucoma who underwent TSCPC with the Oculight laser system (IRIS Medical Instruments) with trans-corneal TI (TSCPC-TI) using a novel low-cost torchlight method. Children completing a minimum 1-year follow-up were analyzed. They were compared with a historical control group of children who underwent TSCPC without TI (TSCPC-No-TI) at the 1-year follow-up period. We analyzed the mean laser energy delivered, post-laser intraocular pressure reduction, number of antiglaucoma medications (AGM), the requirement of retreatment and complications of the procedure in both groups. RESULTS: Forty-two eyes of 35 patients comprised the TSCPC-TI group and were compared with 31 eyes of 21 patients in the TSCPC-No-TI group. The TSCPC-TI group required lower energy than the TSCPC-No-TI group (24.7±7.8 J vs. 47.2±10.9 J, P <0.0001). Mean topical antiglaucoma drug requirement decreased from 2.9±0.08 before treatment to 0.66±0.8 at the end of 1 year in TSCPC-TI and from 2.6±1.0 before treatment to 0.6±0.77 in the TSCPC-No-TI groups, respectively ( P =0.15). There was a significantly reduced dependence of oral acetazolamide in the TSCPC-TI group at 1-year follow-up [5.7% vs. 61.9%, respectively ( P <0.001%)]. No adverse event of hypotony or choroidal detachment was noted in any group. CONCLUSIONS: TSCPC aided by TI with a low-cost torchlight for pediatric refractory glaucoma was found to be effective at 1 year in reducing intraocular pressure and the burden of medication.
Glaucoma , Intraocular Pressure , Child , Humans , Laser Coagulation/methods , Lasers, Semiconductor/therapeutic use , Prospective Studies , Transillumination/adverse effects , Glaucoma/diagnosis , Glaucoma/surgery , Glaucoma/etiology , Ciliary Body/surgery , Treatment Outcome , Retrospective Studies
BACKGROUND: Autonomic nervous system (ANS) imbalance has been reported in a number of psychiatric disorders such as depression, schizophrenia, panic disorder, etc. Autonomic dysfunction in schizophrenia has been associated with the symptoms and manifestation of psychosis. Heart rate variability (HRV) as a tool has been widely used to assess ANS activity and the effect of disease on the sympathovagal balance. Therefore, in the present study, HRV derived from electrocardiogram (ECG) lead II at rest was investigated in order to understand the changes in frequency domain measures in patients with schizophrenia and their first-degree relatives compared to healthy controls. METHODS: Twenty-five patients with schizophrenia, 24 first-degree relatives of patients, and 24 healthy controls (Diagnostic and Statistical Manual of Mental Disorders (DSM)-5; 18-45 years) were included in the study. HRV of the subjects was measured after five minutes of rest. ECG lead II was recorded for five minutes and HRV was analysed in the frequency domain: low frequency (LF), high frequency (HF), total power, and LF/HF ratio. HRV parameters and heart rate were statistically analysed for group comparisons using general linear model multivariate analysis. RESULTS: Patients had significantly higher minimum heart rate and lower HF (normalized units (nu)) compared to their first-degree relatives. A trend was observed in HF (nu) with the lowest in patients followed by healthy controls and first-degree relatives and LF/HF ratio was the highest in patients followed by healthy controls and first-degree relatives, although not statistically significant. No significant difference was found between first-degree relatives and healthy controls. CONCLUSION: The alteration of HRV in schizophrenia could be attributed to reduction in vagal tone and sympathetic dominance, which in turn could serve as state markers of schizophrenia.
Heavy metal pollution and toxicity from water resources have remained a great concern for the entire population. This research demonstrates the capability of carbon quantum dots (CQDs) for fluorescence-based heavy metal detection in different water resources using a fibre-optic spectrometer device. Two different types of CQDs phthalic acid and triethylenediamine (PT CQDs) and Folic acid (FCQDs) were synthesized using microwave irradiation and hydrothermal method, respectively. CQDs were characterized using several techniques such as TEM, EDX, XPS and FTIR. PTCQD and FCQDs both were tested for sensing capability in water reservoirs like household and river water. The results indicate that both CQDs were able to detect all six heavy metal ions (Pb2+, Co2+, Mn3+, Hg2+, Ni2+, Cr3+) tested in the study in the range of 0-100â µM. It was found that FCQDs show a three-fold higher sensitivity and greater resolution than PTCQDs for all the heavy metals samples. The CQDs' sensing capability shows that they can achieve a limit of detection in the range of 0.15-3â µM along with 100% accuracy in terms of recovery with minimal error, these results indicate that both CQDs have a tremendous potential to be used as a sensor for the detection of heavy metals even in complex water matrices. FCQDs show more sensitivity for all metals compared to PTCQDs and used in future as a sensing tool for heavy metal detection with better sensitivity and accuracy with less response time.
In recent decades, fate studies of pesticides have been a topic of interest worldwide due to human health concerns tomato, contain abundant nutritional phytochemicals and lycopene which is known for antioxidant. Tomato is susceptible to many pest, so to overcome from these pests many insecticides are used, leaving residual effects on the crop. So to find out the persistence, the present study was carried out to investigate the residual levels and dissipation behaviour of novaluron 9.45% + lambda-cyhalothrin 1.9% ZC in tomato crop during Rabi session of 2017-18 in randomized block design. The first spray of insecticide was done at fruit formation stage and second spray at 10-day interval at recommended dose @43.31 g a.i. ha-1 and double of recommended dose @86.62 g a.i. ha-1. The residue of novaluron determined by HPLC (high-performance liquid chromatography) on 0 day (two hours after spraying) was 0.154 ppm at lower dose and 0.234 ppm at higher dose. The residue of lambda-cyhalothrin determined by GC ECD (gas chromatography electron capture detector) at 0 day (two hours after spraying) was 0.451 ppm at lower dose and 0.849 ppm at higher dose. The deposition of novaluron 9.45% + lambda-cyhalothrin 1.9% ZC was gradually decreased with increasing days after spraying (DAS). The mean initial deposition of the pesticide novaluron and lambda-cyhalothrin was recorded as 0.154 mg/kg, 0.451 mg/kg, respectively, at the recommended dose @43.31 g a.i. ha-1 while at double of recommended dose @86.62 g a.i. ha-1 novaluron and lambda-cyhalothrin, the mean initial deposition of 0.234 mg/kg and 0.849 mg/kg was recorded, respectively. The residue of the novaluron and lambda-cyhalothrin was at BDL (below determination level) (0.01 and 0.05 ppm) on 5th and 7th day, respectively, at lower dose (x), whereas at higher dose (2x) it was below determination level on 7th and 10th day, respectively. In soil samples, the residue levels were at below the determination level (0.01 mg/kg) for novaluron and (0.05 mg/kg) for lambda-cyhalothrin at both doses. The half-life DT50 of novaluron and lambda-cyhalothrin in the tomato fruit was found to be 2 days at recommended dose (X) @43.31 g a.i. ha-1 for both the pesticide and at double of the recommended dose @86.62 g a.i. ha-1 it was 3 and 2 days, respectively.
Insecticides , Pesticide Residues , Solanum lycopersicum , Humans , Insecticides/analysis , Pesticide Residues/analysis
A supervised field trial was designed in Rajasthan Agricultural Research Institute, Durgapura, Jaipur, Rajasthan, to assess the dissipation and persistence of spiromesifen in chili fruits. Spiromesifen (22.9% suspension concentrate) was sprayed two times at an interval of 10 days at the recommended dose (96 g. a.i. ha-1 ) and double the recommended dose (192 g. a.i. ha-1 ) with four replications. Sampling was done according to the planned interval of days after the second spray. Extraction and cleanup were performed using the modified QuEChERS (quick, easy, cheap, effective, rugged, and safe) method and the spiromesifen residue was analyzed by GC-electron capture detector and confirmation performed using GC-MS. The average initial deposit of spiromesifen was 1.207 mg kg-1 and 1.948 mg kg-1 at the recommended and double the recommended dose, respectively. The half-life values of spiromesifen ranged between 2.7 and 3.2 days at the recommended and double the recommended dose. The safe waiting period was calculated for the respective doses and it was concluded that an average of 7 days is safe for picking. The FSSAI (Food Safety and Standards Authority of India) have set the maximum residue limit of 0.1 mg kg-1 for spiromesifen in green chili. The theoretical maximum residue contribution value of spiromesifen was lower than the maximum permissible intake at both the applications on the 0th day. Hence, there will be no adverse effects on human health after consumption of green chilies.
Insecticides , Pesticide Residues , Humans , Fruit/chemistry , Insecticides/analysis , Half-Life , Electrons , Pesticide Residues/analysis , Environmental Monitoring/methods , India , Kinetics , Chromatography, Gas , Risk Assessment
Iatrogenic Cushing's syndrome is a life-threatening condition which requires an early diagnosis multidisciplinary approach. Despite reports of iatrogenic Cushing's syndrome following nasal or inhaled steroids, its development after topical betamethasone eye drops for a short duration is a less frequently reported or anticipated condition. We describe a 6-week-old infant who developed exogenous Cushing's syndrome following topical steroids after bilateral goniotomy for newborn glaucoma. The child was kept under observation and managed with a physiological dose of hydrocortisone. Parental counselling regarding the proper method of eye drop instillation and signs of steroid toxicity is of vital importance in all cases of pediatric ocular surgeries, especially where bilateral surgeries are undertaken.
Cushing Syndrome , Glaucoma , Trabeculectomy , Infant , Infant, Newborn , Humans , Child , Cushing Syndrome/chemically induced , Cushing Syndrome/diagnosis , Cushing Syndrome/surgery , Glucocorticoids/adverse effects , Intraocular Pressure , Steroids/adverse effects , Iatrogenic Disease
Childhood glaucoma is a treatable cause of blindness, provided it is recognized, diagnosed, and treated in time. WHO has estimated that it is responsible for Blind Years second only to cataracts. The fundamental pathophysiology of all childhood glaucoma is impaired outflow through the trabecular meshwork. Anterior segment Dysgeneses (ASD) are a group of non-acquired ocular anomalies associated with glaucoma, characterized by developmental abnormalities of the tissues of the anterior segment. The cause is multifactorial, and many genes are involved in the development of the anterior segment. Over the last decade, molecular and developmental genetic research has transformed our understanding of the molecular basis of ASD and the developmental mechanisms underlying these conditions. Identifying the genetic changes underlying ASD has gradually led to the recognition that some of these conditions may be parts of a disease spectrum. The characterization of genes responsible for glaucoma is the critical first step toward developing diagnostic and screening tests, which could identify individuals at risk for disease before irreversible optic nerve damage occurs. It is also crucial for genetic counseling and risk stratification of later pregnancies. It also aids pre-natal testing by various methods allowing for effective genetic counseling. This review will summarize the known genetic variants associated with phenotypes of ASD and the possible significance and utility of genetic testing in the clinic.
Eye Abnormalities , Glaucoma , Hydrophthalmos , Anterior Eye Segment/pathology , Female , Glaucoma/diagnosis , Glaucoma/genetics , Humans , Mutation , Pregnancy
PURPOSE: To report underlying genetic variants of recently described distinct phenotype of newborn glaucoma: neonatal-onset congenital ectropion uveae (NO-CEU). DESIGN: Prospective cohort study. METHODS: Setting: tertiary care teaching institute. SUBJECTS: Thirteen children with clinical diagnosis of NO-CEU who had completed 1-year follow-up after glaucoma surgery and had undergone clinical exome sequencing (CES) by selective capture and sequencing of the protein-coding regions of the genes including 19 candidate genes for NO-CEU were assessed. The same criteria were applied for evaluating pathogenicity of variants to all the candidate genes. OUTCOME MEASURES: primary-genetic variants found on CES keeping in view the clinical indication of congenital glaucoma; secondary-corneal clarity and intraocular pressure (IOP) at baseline and 1-year follow-up, interventions required to control IOP, and postoperative visual acuity. The genetic variants were correlated with the outcome. RESULTS: All 13 patients diagnosed with NO-CEU had onset of glaucoma at birth and severe bilateral disease. Twelve of 13 (92.3%) patients harbored CYP1B1 variants. Nine of these 12 patients (83.3%) were homozygous for [c.1169G>A(p.Arg390His)] in exon-3 of CYP1B, with 5 common homozygous single-nucleotide polymorphisms flanking the pathogenic variant. They had intractable glaucoma and required multiple surgeries. Six patients had persistent corneal opacities, necessitating optical iridectomies. Three patients were compound heterozygous for CYP1B1 variants, showing [c.1169G>A(p.Arg390His)] along with [c.1103G>A(p.Arg368His)], [c.1103G>A (p.Arg368His)] along with [c.1403_1429dup(p.Arg468_Ser476dup)], and [(c.1063C>T(p.Arg355Ter)] along with [c.1325del(p.Pro442GlnfsTer15)]. These patients had better visual outcomes. CONCLUSIONS: NO-CEU appears to be a phenotypic marker for specific CYP1B1 genotypes, one of which is [c.1169G>A(p.Arg390His)] in our study population. Phenotype recognition is helpful to characterize the underlying genetic variants.
Ectropion , Glaucoma , Hydrophthalmos , Cytochrome P-450 CYP1B1/genetics , DNA Mutational Analysis , Ectropion/congenital , Ectropion/genetics , Glaucoma/diagnosis , Glaucoma/genetics , Glaucoma/surgery , Humans , Hydrophthalmos/diagnosis , Hydrophthalmos/genetics , Hydrophthalmos/surgery , Infant, Newborn , Intraocular Pressure , Mutation , Prospective Studies
AIMS: Hematopoietic acute radiation syndrome (H-ARS) can cause lethality, and therefore, the necessity of a safe radioprotector. The present study was focused on investigating the role of melatonin in granulocytes colony-stimulating factor (G-CSF) and related mechanisms underlying the reduction of DNA damage in hematopoietic system of irradiated mice. MAIN METHODS: C57BL/6 male mice were exposed to 2, 5, and 7.5Gy of whole-body irradiation (WBI), 30 min after intra-peritoneal administration of melatonin with different doses. Mice were sacrificed at different time intervals after WBI, and bone marrow, splenocytes, and peripheral blood lymphocytes were isolated for studying various parameters including micronuclei (MN), cell cycle, comet, γ-H2AX, gene expression, amino acid profiling, and hematology. KEY FINDINGS: Melatonin100mg/kg ameliorated radiation (7.5Gy and 5Gy) induced MN frequency and cell death in bone marrow without mortality. At 24 h of post-WBI (2Gy), the frequency of micronucleated polychromatic erythrocytes (mnPCE) with different melatonin doses revealed 20 mg/kg as optimal i.p. dose for protecting the hematopoietic system against radiation injury. In comet assay, a significant reduction in radiation-induced % DNA tail (p ≤ 0.05) was observed at this dose. Melatonin reduced γ-H2AX foci/cell and eventually reached to the control level. Melatonin also decreased blood arginine levels in mice after 24 h of WBI. The gene expression of G-CSF, Bcl-2-associated X protein (BAX), and Bcl2 indicated the role of melatonin in G-CSF regulation and downstream pro-survival pathways along with anti-apoptotic activity. SIGNIFICANCE: The results revealed that melatonin recovers the hematopoietic system of irradiated mice by inducing G-CSF mediated radioprotection.
Acute Radiation Syndrome/metabolism , Gamma Rays/adverse effects , Granulocyte Colony-Stimulating Factor/metabolism , Hematopoiesis , Melatonin/pharmacology , Radiation Injuries, Experimental/metabolism , Animals , Hematopoiesis/drug effects , Hematopoiesis/radiation effects , Male , Mice , Radiation Injuries, Experimental/drug therapy , Radiation Injuries, Experimental/pathology
PURPOSE: To study the frequency of intrauterine rubella infection in a cohort of neonatal-onset glaucoma (NOG) and its effect on the treatment outcomes. DESIGN: Prospective cohort study. PARTICIPANTS: Infants with NOG presenting to the pediatric glaucoma service at a tertiary care center in northern India at Chandigarh between January 1, and September 30, 2018, with a minimum postoperative follow-up of 1 year were included in this study. METHODS: Rubella immunoglobulin-M (IgM) antibodies were tested in all patients. Surgery for intraocular pressure (IOP) control comprised combined trabeculotomy with trabeculectomy or goniotomy. Presenting features and treatment outcomes at 1 year were compared among infants with and without rubella-IgM antibodies. RESULTS: Of 27 eligible infants, 7 (25.9%) were rubella-IgM positive, and all had bilateral glaucoma. One eye in a rubella-positive baby was an unsightly blind eye and required a prosthesis. A total of 13 eyes of 7 patients were compared with 34 eyes of 20 rubella-negative patients. There was no significant difference in mean age and IOP at presentation. Rubella-positive infants had significantly more opaque corneas (P < 0.001), shorter eyes (P < 0.001), and smaller corneal diameters (P = 0.007) at presentation. Two patients in the rubella group had bilateral cataracts, 3 patients had heart disease, and 1 patient had sensorineural deafness. Salt-and-pepper retinopathy was noted in both rubella-positive infants where fundus evaluation was possible. Despite comparable IOP control (P = 0.51), the corneal clarity remained significantly worse in the rubella-positive patients (P = 0.02). CONCLUSIONS: Twenty-five percent of those with newborn glaucoma had underlying intrauterine rubella infection, thus making them susceptible for development of congenital rubella syndrome (CRS). Neonatal-onset glaucoma is an important component of CRS, which may present without buphthalmos and persistent corneal clouding despite good IOP control.
Glaucoma , Hydrophthalmos , Rubella Syndrome, Congenital , Child , Glaucoma/surgery , Humans , Immunoglobulin M , Infant , Infant, Newborn , Prospective Studies , Retrospective Studies , Rubella Syndrome, Congenital/complications , Rubella Syndrome, Congenital/diagnosis
INTRODUCTION: Deep Learning (DL) and Artificial Intelligence (AI) have become widespread due to the advanced technologies and availability of digital data. Supervised learning algorithms have shown human-level performance or even better and are better feature extractor-quantifier than unsupervised learning algorithms. To get huge dataset with good quality control, there is a need of an annotation tool with a customizable feature set. This paper evaluates the viability of having an in house annotation tool which works on a smartphone and can be used in a healthcare setting. METHODS: We developed a smartphone-based grading system to help researchers in grading multiple retinal fundi. The process consisted of designing the flow of user interface (UI) keeping in view feedback from experts. Quantitative and qualitative analysis of change in speed of a grader over time and feature usage statistics was done. The dataset size was approximately 16,000 images with adjudicated labels by a minimum of 2 doctors. Results for an AI model trained on the images graded using this tool and its validation over some public datasets were prepared. RESULTS: We created a DL model and analysed its performance for a binary referrable DR Classification task, whether a retinal image has Referrable DR or not. A total of 32 doctors used the tool for minimum of 20 images each. Data analytics suggested significant portability and flexibility of the tool. Grader variability for images was in favour of agreement on images annotated. Number of images used to assess agreement is 550. Mean of 75.9% was seen in agreement. CONCLUSION: Our aim was to make Annotation of Medical imaging easier and to minimize time taken for annotations without quality degradation. The user feedback and feature usage statistics confirm our hypotheses of incorporation of brightness and contrast variations, green channels and zooming add-ons in correlation to certain disease types. Simulation of multiple review cycles and establishing quality control can boost the accuracy of AI models even further. Although our study aims at developing an annotation tool for diagnosing and classifying diabetic retinopathy fundus images but same concept can be used for fundus images of other ocular diseases as well as other streams of medical science such as radiology where image-based diagnostic applications are utilised.
Fluorescent pH biosensors have gained importance owing to their low cost utilization in real time monitoring of biological and food samples in comparison to conventional pH meters. The research reports a novel method of ultrasonic atomization for developing a fluorescent pH sensor for real-time analysis made of Fluorescein isothiocyanate (FITC)-dextran/FITC-dextran-Tris (2, 2'-bipyridyl) dichlororuthenium (II) hexahydrate as indicator and reference fluorophores, respectively. The process of ultrasonic atomization ensures formation of monodisperse dye immobilized alginate microspheres ensuring efficient pH sensing. The developed biosensor was tested on milk samples, which has a short life span and shows a significant fall in pH with time due to microbial spoilage. The proposed biosensor showed a linear range of pH 4-8 (R2 between 0.96-0.99 for different single/dual fluorophore biosensors) which suitably cover the pH of milk during the entire storage period and spoilage. The % recovery for predicted pH falls between 90-110% compared against standard pH meter, indicating a good accuracy of estimation and low turnaround time (10 min). Thus, real-time monitoring using fluorescent pH biosensor for milk samples may profoundly improve the economics of losses occurring in processing and storage with capability of in-package continuous quality assessment.
