Safety monitoring of precautionary third dose of COVID-19 vaccines in a district in Northern India.

Background: The World Health Organization (WHO) declared Coronavirus disease-19 (COVID-19) caused by Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) a pandemic on March 11, 2020. On 16th January 2021, India began its vaccination programme using two COVID-19 vaccines (Covishield and Covaxin). Precautionary dose (booster shots) was administered to health and front-line workers in the beginning and then to all eligible populations. Material and Methods: This was a descriptive observational study conducted in the COVID-19 vaccination centres of Karnal district and the ADR monitoring centre, KCGMC, Karnal. During the visits to vaccination centres, all beneficiaries of the precautionary third dose of COVID-19 vaccines as well as healthcare workers were sensitized to report in case of any adverse event following vaccination as part of the policy of the vaccination programme run by the government and Pharmacovigilance Programme of India. The data were collected in suspected adverse drug reaction (ADR) reporting form version 1.4, and causality assessment was done as per the WHO-UMC scale. The data were analysed as simple proportions and percentages. Results: The booster dose was administered to 72,853 individuals, while the 1st dose and 2nd dose were given to 13,30,042 and 10,73,050, respectively. Only three ADRs were reported with the booster dose in 34 vaccination centres in the Karnal district. These three ADRs were classified as unlikely on causality assessment and hence not included in the analysis. Conclusion: The booster dose administered for the prevention of COVID-19 has been found to be reasonably safe. The population who received COVID-19 booster doses was significantly less than the populations who received the first and second doses, which suggests a low acceptance rate.

Molecularly imprinted polymers in the analysis of chlorogenic acid: A review.

Chlorogenic acid, a phenolic compound, is prevalent across various plant species and has been known for its pharmacological advantages. Health care experts have identified chlorogenic acid as a potential biomarker for treatment of a wide range of illnesses. Therefore, achieving efficient extraction and analysis of chlorogenic acid from plants and their products has become essential. Molecularly imprinted polymers (MIPs) are highly effective adsorbent for the extraction of chlorogenic acid from complex matrices. Currently, there is a lack of comprehensive review article that consolidate the methods utilized for the purification of chlorogenic acid through molecular imprinting. In this context, we have surveyed the common approaches employed in preparing MIPs specifically designed for the analysis of chlorogenic acid, including both conventional and newly developed. This review discusses the advantages, limitations of polymerization techniques and proposed strategies to produce more efficient MIPs for chlorogenic acid enrichment in complex samples. Additionaly, we present advanced imprinting methods for designing MIPs, which improve the adsorption capacity, sensitivity and selectivity towards chlorogenic acid.

Adverse events following Covaxin administration among adolescents (15-18 years) - A pharmacovigilance study in a district in Northern India.

Introduction: The study was undertaken to observe the adverse event following immunization (AEFI) to the Covaxin vaccine in young adolescents in the age group of 15-18 years in a district in Northern India. The study was conducted to assess the safety profile of the COVAXIN vaccine. Methodology: This was a prospective observational study conducted at rural and urban health centers of a district in Northern India. We included the beneficiaries of the COVAXIN between the age of 15 and 18 years. The administration of the COVAXIN occurred in our district from January 2022. Periodic visits were conducted to the urban and rural health centers of the city to record any suspected adverse drug reaction following immunization in the defined population. The study was conducted for a period of 1 year (January 2022 to December 2022). Results: A total of 72,771 adolescents (15-18 years) received the first dose of Covaxin and 49,046 received the second dose. No adverse drug event following immunization was reported during the study. Conclusion: Thus, it can be concluded that Covaxin was found to be safe in adolescents (15-18 years).

Recent advances in development of electrochemical biosensors for the detection of biogenic amines.

Biogenic amines (BAs) are widely found in food as a consequence of diverse factors including free amino acid availability, microbial production of decarboxylases, and variations in processing and storage conditions. Hence, BAs are considered as an important marker for determining the freshness and quality of food. Owing to the documentation of BAs in different dietary products, their numerous negative impacts on human health have reported to be a serious concern in past few decades. Therefore, the quantification of these chemical species in food becomes crucial as it can immensely contributes toward control of new episodes on food intoxication in humans. In this line, various chromatographic and colorimetric methods have been developed to detect BAs. However, these methods are in use from a longer time, still are limited by high cost, lengthy procedures, huge infrastructure and skilled personnel requirements that hinder their on-field application. In pursuit of a reliable method offering accurate detection of BAs, this review presents the state-of-the-art of electrochemical strategies for BAs sensing in food. The core of the review discusses about the widely employed electrochemical transducers, such as amperometric, potentiometric, impedimetric and conductometric-based BAs biosensors with significant findings of research work conducted previously. The application of electrochemical sensors to analyze BAs in different fields including food systems (fermented and non-fermented types) and smart packaging systems has been reviewed. Moreover, existing challenges and further available prospects for the development of rapid, facile, and sensitive electrochemical strategies for on-site determination of BAs have also been discussed.

Effectiveness of 13-valent pneumococcal conjugate vaccine on radiological primary end-point pneumonia among cases of severe community acquired pneumonia in children: A prospective multi-site hospital-based test-negative study in Northern India.

INTRODUCTION: Community acquired pneumonia (CAP) is a leading cause of under-five mortality in India and Streptococcus pneumoniae is the main bacterial pathogen for it. Pneumococcal Conjugate Vaccine 13 (PCV13) has been introduced in a phased manner, in the national immunization program of India since 2017/2018. The primary objective of this study was to evaluate the effectiveness of PCV13 on chest radiograph (CXR)-confirmed pneumonia, in children hospitalized with WHO-defined severe CAP. METHODS: This prospective, multi-site test-negative study was conducted in a hospital-network situated in three districts of Northern India where PCV13 had been introduced. Children aged 2-23 months, hospitalized with severe CAP and with interpretable CXR were included after parental consent. Clinical data was extracted from hospital records. CXRs were interpreted by a panel of three independent blinded trained radiologists. Exposure to PCV13 was defined as ≥2 doses of PCV13 in children aged ≤ 12 months and ≥ 1 dose(s) in children > 12 months of age. Our outcome measures were CXR finding of primary endpoint pneumonia with or without other infiltrates (PEP±OI); vaccine effectiveness (VE) and hospital mortality. RESULTS: From 1st June 2017-30th April 2021, among 2711 children included, 678 (25.0%) were exposed to PCV1. CXR positive for PEP±OI on CXR was found in 579 (21.4%), of which 103 (17.8%) were exposed to PCV. Adjusted odds ratio (AOR) for PEP±OI among the exposed group was 0.69 (95% CI, 0.54-0.89, p = 0.004). Adjusted VE was 31.0% (95% CI: 11.0-44.0) for PEP±OI. AOR for hospital mortality with PEP±OI was 2.65 (95% CI: 1.27-5.53, p = 0.01). CONCLUSION: In severe CAP, children exposed to PCV13 had significantly reduced odds of having PEP±OI. Since PEP±OI had increased odds of hospital mortality due to CAP, countrywide coverage with PCV13 is an essential priority.

Molecularly Imprinted Polymer-Based Electrochemical Sensor for Rapid and Selective Detection of Hypoxanthine.

In this paper, we report on the coupling of an electrochemical transducer with a specifically designed biomimetic and synthetic polymeric layer that serves as a recognition surface that demonstrates the molecular memory necessary to facilitate the stable and selective identification of the meat-freshness indicator hypoxanthine. Consumer preferences and the food safety of meat products are largely influenced by their freshness, so it is crucial to monitor it so as to quickly identify when it deteriorates. The sensor consists of a glassy-carbon electrode, which can be regenerated in situ continuously, functionalized with molecularly imprinted polymers (MIPs) and a nanocomposite of curcumin-coated iron oxide magnetic nanospheres (C-IO-MNSs) and multiwalled carbon nanotubes (MWCNTs) that enhance the surface area as well as the electroactive characteristics. The electrochemical behavior of the fabricated sensor was analyzed by both cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). Differential pulse voltammetric studies revealed the rapid response of the proposed sol-gel-MIP/MWCNT/C-IO-MNS/GCE sensor to hypoxanthine in a concentration range of 2-50 µg/mL with a lower limit of detection at 0.165 µg/mL. Application of the newly fabricated sensor demonstrated acceptable recoveries and satisfactory accuracy when used to measure hypoxanthine in different meat samples.

Cell-free arsenic biosensors with applied nanomaterials: critical analysis.

Arsenic is a ubiquitously found metalloid in our ecosystem because of natural and anthropogenic activities. People exposed to a higher level of arsenic become susceptible to several disorders, including cancer. According to current statistics, the population chronically exposed to arsenic has surpassed 200 million. Therefore, its detection in our environment is of great importance. There are many analytical techniques for the assessment of arsenic in different kinds of environmental samples. Among these techniques, the biosensor is considered a convenient platform and a widely applied analytical device for rapid qualitative and quantitative analysis in the field of environmental monitoring, food safety, and disease diagnosis. Today, there is a trend of including nanomaterials in sensors and biosensors because it empowers researchers to explore new arsenic detection methods and to enhance their analytical capabilities. In this review article, we summarized the latest developments in arsenic biosensors in particular with emphasis on the works based on cell-free approaches that are protein/enzyme-based, DNA-based, and aptamer-based utilizing various transduction platforms. In the meantime, we compared the capabilities that were related to these cell-free arsenic biosensors. This review article also highlights the development and application of novel nanomaterials for arsenic detection.

Review on recent advances in fabrication of enzymatic and chemical sensors for hypoxanthine.

Hypoxanthine is an important product of the nucleotide degradation pathway. It has been considered as a potential marker for assessing meat freshness and clinical diagnosis. In the review, we focus on advancement made in the fabrication of hypoxanthine sensors. Several traditional methods are being utilized for the detection of hypoxanthine, but these methods are expensive, complex, require pretreatment of the sample which is time-consuming and trained persons to operate. Sensors have emerged as simple, rapid, economic, disposable, and portable tools for hypoxanthine detection in biological samples. In particular, the review describes the significant role of hypoxanthine in clinical and food applications. Classification of sensors into enzymatic and non-enzymatic sensors along with the different methods used for xanthine oxidase immobilization and type of transducers used for hypoxanthine detection are briefly explained.

Epidemiology of Hypoxic Community-Acquired Pneumonia in Children Under 5 Years of Age: An Observational Study in Northern India.

BACKGROUND: Community-acquired pneumonia (CAP) is the leading cause of under-five mortality in India. An increased risk of mortality has been reported in cases of hypoxic pneumonia. METHODS: The primary objective of this study was to assess the proportion of children aged 2-59 months, hospitalized with hypoxic CAP, as well as socio-demographic, clinical, and radiological features associated with it. The secondary objective was to determine the risk of mortality among hospitalized cases of hypoxic CAP. This prospective, observational study was conducted in four districts of Northern India, between January 2015 and April 2021. A hospital-based surveillance network was established. Inclusion criteria were as follows: (a) child between 2 and 59 months, (b) hospitalization with symptoms of WHO-defined CAP, (c) resident of project district, (d) illness of <14 days, and (e) child had neither been hospitalized for this illness nor recruited previously. Children whose chest x-rays (CXRs) were either unavailable/un-interpretable and those that received any dose of pneumococcal conjugate vaccine-13 were excluded. Hypoxic pneumonia was defined as oxygen saturation <90% on pulse oximetry or requiring oxygen supplementation during hospital stay. RESULTS: During the study period, 71.9% (7,196/10,006) children of severe pneumonia were eligible for inclusion, of whom 35.9% (2,580/7,196) were having hypoxic pneumonia. Female gender and use of biomass fuel for cooking increased the odds of hypoxic CAP. Clinical factors like wheezing, pallor, tachypnea, low pulse volume, presence of comorbidity, general danger signs, severe malnutrition, and radiological finding of primary end-point pneumonia ± other infiltrates (PEP±OI) also increased the odds of hypoxic CAP in a conditional logistic regression model. Adjusted odds ratio for mortality with hypoxia was 2.36 (95% CI: 1.42-3.92). CONCLUSION: Almost one-third of cases hospitalized with severe CAP had hypoxia, which increased chances of mortality. Besides known danger signs, certain newer clinical signs such as pallor and wheezing as well as PEP+OI were associated with hypoxic CAP. Therefore, objective assessment of oxygen saturation must be done by pulse oximetry in all cases of CAP at the time of diagnosis.

Reusable Enzymatic Strip for Detection of Arsenic

HIGHLIGHTS Arsenic is considered as one of the highly hazardous elements in the environment and a serious carcinogen for the human health. An enzymatic method has been described by using arsenite oxidase for arsenic detection. Residual activity of the immobilized enzyme was 43% of the initial activity after being recycled 10 times.

Abstract Arsenic is considered as one of the highly hazardous elements in the environment and a serious carcinogen for the human health. More attention has taken towards the arsenic due to its presence in ground water in India, China, Bangladesh, Inner Mongolia and several other regions of the world. It's been a challenge to remove arsenic due to the lack of its efficient detection approach in the complicated environmental matrix. The proposed method describes an enzymatic method for arsenic determination using arsenite oxidase, which catalyzes the oxidation of arsenite to arsenate. Hence, a colorimetric PVC strip with immobilized arsenite oxidase has been developed to detect the arsenic concentration and also having potential for the field-testing. The influence of the optimal conditions i.e. pH, temperature, storage stability, and reusability of free and immobilized enzyme were evaluated and compared. The results have shown that the stabilities were significantly enhanced compared with free counterpart. Residual activity of the immobilized enzyme was 43% of the initial activity after being recycled 10 times. We approve that this novel low cost immobilized carrier presents a new approach in large scale applications and expected to act as a model for establishment of indigenous arsenic sensor in miniature form.

Biosensors for penicillin quantification: a comprehensive review.

Penicillins represent most commonly prescribed and salient part of antibacterial armamentarium. Due to lack of proper guidance and regulations, especially in developing countries they are indiscriminately applied in agricultural sectors (livestock farming, aquaculture and plants). Major concerns related to remaining residues of penicillins in food or environment are allergy, development of antibacterial resistance, environmental pollution, economical losses to food industries, consumers and food safety. Researchers of different disciplines are developing reliable detection methods for penicillins in various samples. Among them biosensors are attracting considerable attention primarily for their instant detection, convenience in application, on-site monitoring and portability. Nowadays, they are becoming more sophisticated with the help of modern approaches such as nanotechnology. This review article summarizes the research literature on advancements and recent trends in the field of biosensors for penicillins quantification till date. Different domains of biosensors (electrochemical, optical, mass-sensitive and thermal) are discussed for penicillins along with their applicability.

Novel approach using activated cellulose film for efficient immobilization of purified diamine oxidase to enhance enzyme performance and stability.

The presence of various contaminants in foodstuffs has led to serious public health concerns. Diamine oxidase (DAO) has attracted tremendous attention for guarding food safety as well as clinical and environmental industries. In this study, DAO from Pisum sativum (Pea) seedlings was extracted and purified by dialysis and gel filtration. Purified DAO was covalently immobilized onto the surface of nitrocellulose membrane using glutaraldehyde. The obtained bioaffinity support has efficiently shown high yield immobilization of DAO from pea seedlings. The optimal conditions of free and immobilized DAO activity were evaluated against the substrate, Putrescine dihydrochloride. The influence of pH, temperature, storage stability, and reusability of immobilized enzyme with comparison to the free enzyme was studied and the results showed that the stabilities were significantly enhanced compared with free counterpart. Residual activity of the immobilized enzyme was 59% of the initial activity after being recycled 10 times. We approve that this novel low cost immobilized DAO carrier presents a new approach in large scale applications.

A novel spectrophotometric method for simultaneous estimation of dibenzothiophene and 2-hydroxybiphenyl in their mixed spectrum and its application in screening of specific biodesulfurizing microbes.

The desulfurization of fuel is currently enforced to meet environmental legislation and prevent pollution. The use of specific biodesulfurizing microbes with a unique 4S pathway allows the desulfurization without compromising the quality of fuel. These specific microbes can be screened by the detection of 2-hydroxybiphenol (2-HBP) in desulfurizing mixture of dibenzothiophene (DBT). At present, colorimetric Gibb's assay is the most commonly employed screening method which requires a specific reagent, i.e., 2,6-dichloroquninone-4-chloramide. In the present study, a novel and simple spectrophotometric method was developed for the detection of 2-HBP for screening purpose based on dual wavelength method. The developed method facilitates the simultaneous analysis of DBT desulfurization and 2-HBP production in a sample by merely measuring the absorbance differences at two specified wavelengths, i.e., ΔA (λ 320-λ 247) for DBT and ΔA (λ 286-λ 324) for 2-HBP. The developed method was used to screen 57 microbes and two specific desulfurizing microbes Bacillus flexus MS-5 and Bacillus cereus BR-31 were selected based on 2-HBP production. The outcomes of developed method were validated by HPLC analysis. The strains MS-5 and BR-31 were employed in biodesulfurization and resulted in 54.88 ± 1.12% and 55.72 ± 1.32% desulfurization of 1.0 mM DBT, respectively. The developed method for screening of specific desulfurizing microbes does not require any specific reagent or sophisticated instrument in spite of being quick and reliable. The microbes selected by developed method exhibited excellent potential for biodesulfurization of fuel.

Enzymatic biosensors for the quantification of biogenic amines: a literature update.

The present review emphasizes on the quantification of biogenic amines (BAs) which are regarded as a quality indicator of food freshness or spoilage and for evaluating microbial action while food processing. BAs have various potential adverse effects on human health and they are widely found in varying concentrations in different food stuffs. In the quest for a reliable method for their precise detection, BA biosensors have emerged as an efficient tool which enables rapid and accurate assessment in miniature form. Various combinations of amine oxidase enzymes have been used for the fabrication of biosensors in order to enhance specific biorecognition and signal transduction. This article also summarizes the widely employed components used in the construction of a pertinent biosensor and the research results conducted previously. The meticulous description regarding the choice of transducers and the significant role of mediators in a high response biosensor has been reviewed. Moreover, it also encompasses the utilization of highly attractive electrolytic characteristics of nanoparticles to enhance the specificity and accuracy of BA biosensors.

Optimization of rhamnolipid production from Pseudomonas aeruginosa PBS towards application for microbial enhanced oil recovery.

The present work reveals the potential of biosurfactant producing P. aeruginosa PBS for microbial enhanced oil recovery (MEOR). The biosurfactant production medium and culture conditions were optimized using response surface methodology. The optimization of media components and process parameters was consecutively executed in two sets of experimental runs designed by central composite rotatable design (CCRD). The maximum biosurfactant yield was attained with 2% fresh inoculum of P. aeruginosa PBS in minimal salt medium (pH 7), possessing 2.17% sodium citrate as C-source and 0.5% yeast extract as N-source, after 48 h upon incubation at 30 °C/150 rpm. Under optimum conditions, biosurfactant yield was increased more than threefold and turned out to be 2.65 g/L as compared to 0.82 g/L under previous conditions. The biosurfactant was characterized as a glycolipid comprising of four rhamnolipid homologs (RhaRhaC10C10, RhaRhaC8C10, RhaRhaC12C10/RhaRhaC10C12, RhaC10C10) by thin layer chromatography, fourier transform infrared spectroscopy, nuclear magnetic resonance and mass spectrometry. The produced biosurfactant was highly efficient for oil recovery application showing extreme reduction in surface tension of medium (71.80 to 23.76 mN/m), immense hydrocarbons emulsification capacity (50-60%) and greater stability at wide range of temperature (4-100 °C) and pH (4-10) along with an excellent (56.18 ± 1.59%) additional oil recovery in sand-pack column lab test.

L-arginine biosensors: A comprehensive review.

Arginine has been considered as the most potent nutraceutics discovered ever, due to its powerful healing property, and it's been known to scientists as the Miracle Molecule. Arginine detection in fermented food products is necessary because, high level of arginine in foods forms ethyl carbamate (EC) during the fermentation process. Therefore, L-arginine detection in fermented food products is very important as a control measure for quality of fermented foods, food supplements and beverages including wine. In clinical analysis arginine detection is important due to their enormous inherent versatility in various metabolic pathways, topmost in the synthesis of Nitric oxide (NO) and tumor growth. A number of methods are being used for arginine detection, but biosensors technique holds prime position due to rapid response, high sensitivity and high specificity. However, there are many problems still to be addressed, including selectivity, real time analysis and interference of urea presence in the sample. In the present review we aim to emphasize the significant role of arginine in human physiology and foods. A small attempt has been made to discuss the various techniques used for development of arginine biosensor and how these techniques affect their performance. The choice of transducers for arginine biosensor ranges from optical, pH sensing, ammonia gas sensing, ammonium ion-selective, conductometric and amperometric electrodes because ammonia is formed as a final product.

Diagnostic accuracy of fine-needle aspiration cytology of thyroid gland lesions: A study of 200 cases in Himalayan belt.

AIMS: The study is undertaken to correlate the fine-needle aspiration cytology (FNAC) findings with histopathology in a spectrum of thyroid lesions and to find the diagnostic accuracy of fine-needle aspiration (FNA) so that unnecessary thyroidectomies can be avoided in benign lesions. MATERIALS AND METHODS: This study was carried out over the period of 1-year (May 1, 2012-April, 30 2013). FNA specimens obtained from 200 patients were analyzed. Of these, only 40 patients underwent surgery and their thyroid specimens were subjected to histopathological examination. RESULTS: The age of the patients ranged from 9 to 82 years with mean age being 43 years. There was female preponderance, with male to female ratio being 1:7. On cytology out of 200 cases, 148 (74%) were benign, 25 (12.5%) were malignant, 16 (8%) were indeterminate, and 11 (5.5%) were nondiagnostic. Only 40 patients underwent surgery. On histopathology, 21 (52.5%) cases were benign and 19 (47.5%) were malignant. The statistical analysis of cytohistological correlation for both benign and malignant lesions revealed sensitivity, specificity, and diagnostic accuracy of 84%, 100% and 90%, respectively. CONCLUSION: FNAC is a minimally invasive, highly accurate and cost-effective procedure for the assessment of patients with thyroid lesions and has high -sensitivity and specificity. It acts as a good screening test and avoids unnecessary thyroidectomies.

Bioremediation of Toxic Heavy Metals: A Patent Review.

BACKGROUND: The global industrialization is fulfilling the demands of modern population at the cost of environmental exposure to various contaminants including heavy metals. These heavy metals affect water and soil quality. Moreover, these enter into the food chain and exhibit their lethal effects on the human health even when present at slightly higher concentration than required for normal metabolism. To the worst of their part, the heavy metals may become carcinogenic. Henceforth, the efficient removal of heavy metals is the demand of sustainable development. Remedy: Bioremediation is the 'green' imperative technique for the heavy metal removal without creating secondary metabolites in the ecosystem. The metabolic potential of several bacterial, algal, fungal as well as plant species has the efficiency to exterminate the heavy metals from the contaminated sites. Different strategies like bioaccumulation, biosorption, biotransformation, rhizofilteration, bioextraction and volatilization are employed for removal of heavy metals by the biological species. Bioremediation approach is presenting a splendid alternate for conventional expensive and inefficient methods for the heavy metal removal. CONCLUSION: The patents granted on the bioremediation of toxic heavy metals are summarized in the present manuscript which supported the applicability of bioremediation technique at commercial scale. However, the implementation of the present information and advanced research are mandatory to further explore the concealed potential of biological species to resume the originality of the environment.

Cytology of plasma cell rich effusion in cases of plasma cell neoplasm.

BACKGROUND: Multiple myeloma or plasmacytoma resulting in malignant effusion is rarely described in literature. AIMS: In this paper, we have studied the seven rare cases of plasma cell infiltration in effusion fluid. MATERIALS AND METHODS: We studied six cases of pleural fluid and one case of ascetic fluid. Detailed cytological features, clinical history, bone marrow examinations, serum electrophoresis, and immunofixation data were analyzed. RESULT: There were two cases of plasmacytoma, four cases of multiple myeloma, and one case of plasmablastic lymphoma. On cytology, all the cases showed excess plasma cells along with mesothelial cells and lymphocytes on effusion cytology smear. CONCLUSION: Plasma cell rich effusion in cases of plasma cell tumor is rare. However, on cytology these cases do not pose much problem if relevant history is known.

Zinc finger peptide based optic sensor for detection of zinc ions.

In the present work, polyacrylamide gel has been used as a matrix for the immobilization of zinc finger peptide and fluorescent dye acrydine orange on the micro well plate to fabricate the fluorescence based biosensor for the detection of zinc ions in milk samples. The fluorescent dye moves in the hydrophobic groove formed after folding of the peptide in the presence of zinc ions. Under optimized conditions, linear range was observed between 0.001µg/l to 10µg/l of Zinc ions, with a lowest detection limit of 0.001µg/l and response time of 5min. Presented biosensor has shown 20% decrease in fluorescent intensity values after 5 regenerations and stable for more than one month, stored at 4°C. Interference study with other metal ions like lead, cadmium and copper showed a negligible change in fluorescence intensity in comparison to zinc ions. Developed bio sensing system was found to be novel, quick, reliable, miniaturized, stable, reproducible and repeatable and specific for zinc ion, which has been applied to various milk samples.