Nanobiotechnology and Biosensors

Recently, a novel approach to a highly sensitive and quantitative detection of rare earth element (REE) ions including La3+, Eu3+ and Tb3+, by the polymerase chain reaction (PCR) technique, has been reported. The detection of REE ions is based on the catalytic nature of REE ions targeting the deoxyribonucleic acid (DNA), thus monitoring of the ions can be achieved by reading the level of intact DNA by PCR. Despite of its high sensitivity (at ppb to ppt levels), the conventional PCR-based REE detection protocol requires certain length of time (1-2 hours). In the present study, we modified the PCR-based REE detection protocols by employing the high-speed PCR, and performed the automated and rapid detection of La3+ in small-sized aqueous samples within 5min.

The efficient detection of charged biomolecules by biosensor with appropriate semiconducting nanomaterials and with optimum device geometry has caught tremendous research interest in the present decade. Here, the performance of various label-free electronic biosensors to detect bio-molecules is investigated by simulation technique. Silicon nanowire sensor, nanosphere sensor and double gate field effect transistor (DGFET) sensor with different device parameters are reported here and their performances are compared. For the three types of sensors, radius of the nanowire, radius of the nanosphere and the silicon body thickness for the DGFET are varied to compare their selectivity, sensitivity, settling time etc. The result of adjustment of the flow of the fluid is also investigated by simulation.

In this paper, we propose a new field effect (FE) sensor for fast detection of glycated albumin (GA) based on thiol modified aptamer (TMA). A p-type Si/ (100 nm) SiO 2 wafer was used, where the SiO 2 layer acts as the gate insulator. This gate insulator is then decorated with a layer of randomly oriented ZnO nanorods, coated with 40 nm of Au to act as binding sites for the TMA. We have shown that the addition of GA significantly reduces the conductivity of the p-type Si channel, which can be used to determine the GA concentration in the test solution. The ZnO/Au/TMA/GA layer can induce negative charges in the Si channel underneath the gate insulator, which is followed by the depletion of the positively charged carriers of the Si, decreasing the conductivity. Accordingly, the charge carriers in the Si channel show a steady decline with increasing GA concentration. We have shown that this decrease in conductivity can be further tuned by varying the gate voltage. The sensor presented here can be used as a fast and reliable sensor for determination of GA.

Biosensors are being used for highly sensitive and selective recognition of biological macromolecules. The impedance based biosensor utilizes the electrical impedance measurements between interdigitated electrodes integrated into a microchannel containing the target cells in a suspension medium. The detection is based on measuring the change in impedance caused by the presence of bacteria. In the experimental methods an impedance analyzer was used to measure the electrical impedance. The first impedance measurement was done with the microfluidic system containing the suspension medium alone and is referred to as the control signal. The subsequent impedance measurements were performed with known concentration of Escherichia coli (E. coli) cells added to the same suspension medium. In this paper we describe the simulation of impedance measurements using the electromagnetics module of COMSOL Multiphysics TM , a commercially available modeling package.

This paper reports on the high sensitivity of sub-spherical In 2 O 3-Pt nanoparticles (NPs) for detecting ppb levels of acetone, a biomarker for diabetes. The In 2 O 3-Pt NPs, in the form of monodisperse metal-oxide In 2 O 3 NPs with diameters of 6–8 nm, decorated with 2 wt% Pt metal NPs (2–3 nm) on the surface, were synthesized by a novel non-aqueous sol–gel route. NPs samples were investigated by X-ray powder diffraction (XRPD), using the advanced whole powder pattern modeling (WPPM) method, and high-resolution transmission electron microscopy (HR-TEM). The advantage of this preparative process is that it preserves metallic platinum NPs formed during the synthesis. The highly sensitive acetone sensor based on these NPs, showed a lower detection limit as low as 10 ppb or less, which is the lowest detection limit ever reported for any chemoresistive acetone sensors. This exceptional performance is likely due to the key role played by very small Pt metal NPs uniformly distributed in the In 2 O 3-Pt nanostructure. The developed sensor would be suitable for use as a highly sensitive, practical breath acetone checker for daily diet and diabetes management and diagnosis.

This thesis paper is demonstrated a finite difference time domain (FDTD) analysis of high-performance Ag-graphene fabricated fiber optic surface plasmon resonance (SPR) biosensor for biomedical applications. The proposed SPR Biosensor have a four-layer model which increases the sensitivity is due to the adding graphene layer. The design structure of SPR biosensor can be simulated and monitored by the FDTD method. This sensor can identify the adsorption of samples onto the sensing medium using attenuated total reflection (ATR) technique. The refractive index (RI) is varied owing to the adsorption of different concentration of biomolecules. The FDTD technique is used for detecting biomolecular interactions events by using Lumerical FDTD Software. SPR Biosensor technology has the potential to provide fast and accurate detection, reliable imaging of the electric field. As dielectric prominence of the cancer cells mismatch from the normal cell, for a minor change of RI of the biospecimen taken into regard there will be a shift in the resonant frequency therefore exhibiting a biosensor. The designed sensor can distinguish between normal and cancerous cell. This sensor is capable to identify the DNA sequences of BRCA-1 and BRCA-2 genes which are related to inherited breast cancer. In this study, two specific mutations named 916delTT and 6174delT in the BRCA-1 and BRCA-2 genes are selected for detection of breast cancer. This sensor also can recognize the adsorption of DNA biomolecules onto the sensing medium. The refractive index (RI) is varied owing to the adsorption of different concentration of DNA biomolecules. This sensor is also enabled to detect DNA hybridization along with individual point mutations in BRCA-1 and BRCA-2 gene. In addition, I have identified the hybridization of probe DNA with various concentrations of target DNA corresponding to a mutation of the BRCA-1 and BRCA-2 gene and the analysis of genetic biomarkers (916delTT and 6174delT) for early detection of breast cancer. Momentous metamorphoses were present in the SPR angle and Surface resonance frequency (SRF) curvatures for each of the mutations compared with those of the mutation-type (MR) sequences. This sensor is encouraging diagnostic tool for massive potential, high specificity, massive sensibility and reliable method for identifying mutations and cost-effective at the initial stage breast cancer detection.

Biosensors are favored devices for the fast and cost-effective detection of biological species without the need for laboratories. Microfluidic integration with biosensors has advanced their capabilities in selectivity, sensitivity, controllability, and conducting multiple binding assays simultaneously. Despite all the improvements, their design and fabrication are still challenging and time-consuming. The current study aims to enhance microfluidic-integrated biosensors’ performance. Three different functional designs are presented with both active (with the help of electroosmotic flow) and passive (geometry optimization) methods. For validation and further studies, these solutions are applied to an experimental setup for DNA hybridization. The numerical results for the original case have been validated with the experimental data from previous literature. Convection, diffusion, migration, and hybridization of DNA strands during the hybridization process have been simulated with finit...

Research on the design of enzymatic biosensors through variation of cellulose acetate (CA) membrane composition potentiometricelly has been done.This study aims to obtain cellulose acetate composition that provides optimum performance as a supporting medium immobilization of enzyme acetylcholine esterase (AChE) in the design of biosensors for analysis of pesticide chlorpyrifos and get the level of optimization to test the performance of the biosensor covering %inhibition, Nernst factor (sensitivity), the range of measurement, limit of detection and response time. Biosensor electrode is designed with the immobilization of AChE enzyme on the electrode of gold (Au) which has been coated with a membrane composition variation CA with 5%; 10% and 15% and glutaraldehyde of 25%. The results showed that the biosensor electrode composition CA of 15% and GA of 25% deliver optimum performance in analyzing pesticide chlorpyrifos with the highest sensitivity value that is equal 23.18 mV/decade. Biosensor performance test results for the composition of  SA 5%, 10% and 15% respectively indicate values for% inhibition of 13.61% -51.74%;19.67%-73.01%;13.56% -80.01%. Nersnt factor value (sensitivity) of 11.45 mV/decade; 19 mV/decade and 23.18 mV/decade. Measurement range for all compositions show the same value, namely measurement 1-10-6 ppm. The results also showed a detection limit of the analysis of the same value, namely 10-6 ppm with an average response time to 10 minutes.

Keywords: Biosensor, potentiometric, chlorpyrifos, cellulose acetate, glutaraldehyde, AChE enzyme.

While developing an effective vaccine can take months up to years, detection of infected patients seems like one of the best ideas for controlling the situation. The role of biosensors in containing highly pathogenic viruses, saving lives and economy is evident. A new competitive numerical platform specifically for designing microfluidic-integrated biosensors is developed and presented in this work. Properties of the biosensor, sample, buffer fluid and even the microfluidic channel can be modified in this model. This feature provides the scientific community with the ability to design a specific biosensor for requested point-of-care (POC) applications. First, the validation of the presented numerical platform against experimental data and then results and discussion, highlighting the important role of the design parameters on the performance of the biosensor is presented. For the latter, the baseline case has been set on the previous studies on the biosensors suitable for SARS-CoV, which has the highest similarity to the 2019 nCoV. Subsequently, the effects of concentration of the targeted molecules in the sample, installation position and properties of the biosensor on its performance were investigated in 11 case studies. The presented numerical framework provides an insight into understanding of the virus reaction in the design process of the biosensor and enhances our preparation for any future outbreaks. Furthermore, the integration of biosensors with different devices for accelerating the process of defeating the pandemic is proposed.

Biosensors are favored devices for the fast and cost-effective detection of biological species without the need for laboratories. Microfluidic integration with biosensors has advanced their capabilities in selectivity, sensitivity, controllability, and conducting multiple binding assays simultaneously. Despite all the improvements, their design and fabrication are still challenging and time-consuming. The current study aims to enhance microfluidic-integrated biosensors’ performance. Three different functional designs are presented with both active (with the help of electroosmotic flow) and passive (geometry optimization) methods. For validation and further studies, these solutions are applied to an experimental setup for DNA hybridization. The numerical results for the original case have been validated with the experimental data from previous literature. Convection, diffusion, migration, and hybridization of DNA strands during the hybridization process have been simulated with finite element method (FEM) in 3D. Based on the results, increasing the velocity on top of the functionalized surface, by reducing the thickness of the microchamber in that area, would increase the speed of surface coverage by up to 62%. An active flow control with the help of electric field would increase this speed by 32%. In addition, other essential parameters in the fabrication of the microchamber, such as changes in pressure and bulk concentration, have been studied. The suggested designs are simple, applicable and cost-effective, and would not add extra challenges to the fabrication process. Overall, the effect of the geometry of the microchamber on the time and effectiveness of biosensors is inevitable. More studies on the geometry optimization of the microchamber and position of the electrodes using machine learning methods would be beneficial in future works.

Nanopartikel Fe3O4 dari pasir besi memiliki sifat-sifat fisika dan kimia yang menarik dan memiliki potensi untuk diaplikasikan dalam berbagai bidang. Sifat-sifat fisika nanopartikel Fe3O4 meliputi struktur  kristal, sifat mekanik, optik, akustik, termodinamik, elektromagnetik, listrik, dan vibrasi. Sementara itu, sifat-sifat kimia Fe3O4 meliputi laju reaksi, ikatan kimia, dan stabilitas dalam reaksi kimia. Lebih lanjut, nanopartikel Fe3O4
juga mampu menunjukkan sifat biokompatibel ketika difungsionalisasi dengan polimer yang biokompatibel. Sifat-sifat fisika maupun kimia nanopartikel Fe3O4 tersebut dipengaruhi oleh beberapa faktor, yaitu teknik sintesis, parameter sintesis, fungsionalisasi, dan perlakuan tambahan post sintesis. Dalam paper ini, kami menyajikan review
tentang sintesis, karakterisasi, dan fungsionalisasi nanopartikel Fe3O4
dari pasir besi. Aplikasi nanopartikel Fe3O4 dalam berbagai nanoteknologi  maju  juga dikaji secara detail baik mekanisme
maupun proses fisikanya.

The state-of-the-art in wearable flexible sensors (WFSs) for sweat analyte detection was investigated. Recent advances show the development of inte- grated, mechanically flexible and multiplexed sensor systems with on-site circuitry for signal processing and wireless data transmission. When compared with single-analyte sensors, such devices provide an opportunity to more accurately analyse analytes that are dependent on other parameters (such as sweat rate and pH) by improving calibration from in situ real-time analysis, while maintaining a lightweight and wearable design. Important health conditions can be monitored and on-demand regulating drugs can be delivered using integrated wearable systems but require correlation verification​ between sweat and blood measurements using in vivo validation tests before any clinical application can be considered. Improvements are necessary for device sensitivity, accuracy and repeatability to provide more reliable and personalized continuous measurements. With rapid recent development, it can be concluded that non-invasive WFSs for sweat analysis have only skimmed the surface of their health monitoring potential and further significant advancement is sure to be made in the medical field.

Abstract:  Nanomaterial-modified detection systems represent a chief driver towards the adoption of electrochemical methods, since nanomaterials enable functional tunability, ability to self-assemble, and novel electrical, optical and catalytic properties that emerge at this scale. This results in tremendous gains in terms of sensitivity, selectivity and versatility. We review the electrochemical methods and mechanisms that may be applied in the detection of neurological drugs. We focus on understanding how specific nano-sized modifiers may be applied to influence the electron transfer event to result in gains in sensitivity, selectivity and versatility of the detection system. Specific sections are dedicated to electrodes based on the carbon materials, supporting electrolytes, and on electrochemical detection paradigms for neurological drugs and neurotransmitters. We finally discuss emerging trends and future challenges such as the development of strategies for simultaneous detection of multiple targets with high spatial and temporal resolutions, the integration of microfluidic strategies for analyte preconcentration, the real-time monitoring of neurotransmitter secretions from active cell cultures under electro- and chemotactic cues, aptamer-based biosensors, and the miniaturization of the sensing system for detection in small sample volumes andfor enabling cost savings due to manufacturing scale-up. The Supp. Information includes a list of the key properties of the analytes, viz. pKa values, half-life of drugs and their electro-chemical mechanisms. It also defines analytical figures of merit of the drugs and neurotransmitters. The review contains 198 references in the main manuscript and 207 references in the Supp. Information.

In recent years, gold (Au) and silver (Ag) nanoparticles (NPs) have been the centerstage of improving cancer treatments and therapies, substantially attributed to their size and shape tuneable chemical, optical and photonic properties. Owing to such specialties, diverse shapes of Au and Ag NPs have enabled an efficient cellular uptake along with remarkable improvements in early stage diagnosis of tumors. Robust synthesis methods employing several reducing agents have been the backbone of such enormous strides of Au and Ag NPs, allowing the delivery of much lower drug volumes to minimize the patient sensitization. Probes based on Au and Ag NPs functionalization with biocompatible chemical molecules have substantially improved their in vivo tracking and mediating a site-specific binding leading to improved cancer treatment with minimal risks to normal cells. With a better drug delivery potential of non-spherical shapes, the cylindrical (rod shaped) geometries have recently been investigated to possess higher cellular uptake. The rod shaped surface morphology enables a larger area for drug binding with enhanced possibility to make use of photothermal attributes. The interplay of size and shape dependent biologic activities is regulated by physicochemical changes in the tumor microenvironment, where stable drug-carrier binding is facilitated by surface modification of NPs, through moderate interactive forces ensuring minimal changes in native drug structure. The energy savvy greener methods, like microwave and microemulsions have enabled much better control on the synthesized nanoparticle shapes and geometries, through a regulation of precursor to reducing agent stoichiometries. With this viewpoint, this article focuses on most common synthesis methods of Au and Ag NPs alongside their application in more effective treatment of lung and breast cancers.

The various nanoparticles have been used for positive effect on human health. A large number of the medical projects are under emergent stage. Nanotechnology-based nanomedicine means tools and device are technically designed in such a way which can interact at the molecular level and enhance the therapeutic index of drugs with no side effect. It poses a broad range of application in drug delivery, protein detection, robotics, cancer and cardiac therapy, etc. which are described in detail. Treatment and diagnosis of cancer have been restricted due to their poor sensitivity and specificity respectively. Nanotechnology-based cancer treatment is being developed used for diagnostic purpose. Cancer chemotherapeutic drug is possessed high toxic potential cause adverse effect to the body. For example-hair loss, weight loss and reduce urine and sugar formation. By using nanotechnology, enhance the therapeutic index of cancer chemotherapeutic drug, their tolerability, and efficacy and suppress their toxic effect. It also enhances pharmacokinetics, pharmacodynamics as well as bioavailability and provides better safety profile. In this review, other modalities of different aspects are being discussed such as potential hazards of nanoparticle in addition to microbivores and nanosome, etc. Urothelial cancer is cancer occur in the urinary bladder. Various kinds of nanoparticle are being used in diagnosis and treatment of urothelial cancer. In this review, discuss the types of course of treatment and nanoparticle used in the treatment of various kinds of disease. It is based on the stage of urothelial cancer. In this reviewed we have summarized the pharmaceutical application of Chitosan-based nanoparticle. Chitosan is derived from chitin are used as the pharmaceutical carrier for many drugs and vaccines. Being already observed the benefit of nanomedicine-based products. Hence, in this review, we have discussed the fundamental characteristic of nanomedicine and its clinical application in the field of medicine.

«Aspectos éticos de la nanotecnología en la atención a la salud es un recorrido desde el surgimiento y características de las nanotecnologías a su aplicación en el campo de la salud y medicina, pasando por las implicaciones éticas, y lo que se considera la ética de las nanotecnologías. El texto está abrumadoramente referenciado, lo cual facilita al lector interesado perseguir caminos de pensamiento o temáticas paralelas. Álvarez Díaz enfoca las disyuntivas éticas de la nanomedicina desde la filosofía deliberativa del médico y filósofo Diego Gracia Guillén, donde el juicio prudente y la deliberación constituyen la guía; e intuye las dificultades de una democracia deliberativa en la sociedad actual, pero al mismo tiempo su alternativa.»
Del Prólogo, por Guillermo Foladori

La primera versión de este trabajo consiguió el accésit al “Premio del Colegio Oficial de Médicos de Valladolid” 2012, otorgado por la Real Academia de Medicina y Cirugía de Valladolid, España, de la cual el autor es Académico Correspondiente. El haber sometido el texto a la revisión de un Comité Editorial y a la dictaminación por pares académicos ha tenido aportes importantes. Con todo ello ha ganado no solamente el texto final, sino también el lector.
El autor

While developing an effective vaccine can take months up to years, detection of infected patients seems like one of the best ideas for controlling the situation. The role of biosensors in containing highly pathogenic viruses, saving lives and economy is evident. A new competitive numerical platform specifically for designing microfluidic-integrated biosensors is developed and presented in this work. Properties of the biosensor, sample, buffer fluid and even the microfluidic channel can be modified in this model. This feature provides the scientific community with the ability to design a specific biosensor for requested point-of-care (POC) applications. First, the validation of the presented numerical platform against experimental data and then results and discussion, highlighting the important role of the design parameters on the performance of the biosensor is presented. For the latter, the baseline case has been set on the previous studies on the biosensors suitable for SARS-CoV, ...

Amperometric glucose biosensor was fabricated by immobilizing glucose oxidase (GOx) onto chitosannanoparticles (CSNPs) in gold electrode. The chitosan nanoparticles were synthesized from gladiusof squid, Uroteuthis duvauceli by ionic gelation process. The morphology and functional groups ofCSNPs were characterized using transmission electron microscopy (TEM) and Fourier transform infraredspectroscopy (FTIR) respectively. The electrochemical glucose sensing properties of CSNPs based elec-trode (Au/CSNPs/GOx) was analyzed relatively with commercial chitosan particles utilized electrode(Au/CS/GOx). The surface morphology of bare Au, Au/CSNPs and Au/CS electrodes were observed usingscanning electron microscopy (SEM). The cyclic voltammetry measurements revealed that both the elec-trodes exhibit high electrocatalytic ability towards glucose detection in the presence of oxygen. Thedeveloped biosensors possessed good amperometric response towards glucose with linear detectionrange from 0.001 to 1 mM with ≤2 s response time. The Au/CSNPs/GOx biosensor showed high sensitivityof 156.27 A mM−1cm−2with low detection limit of 1.1 M. The Michaelis–Menten kinetics evaluated forthe electrodes displayed low value (Kappm= 0.625 mM) representing an excellent substrate affinity towardsthe enzyme. Moreover, this biosensor demonstrated better repeatability, reproducibility and stability.

Since the dissolution of polyolefins is a chronic problem, melt processing has been tacitly accepted as an obligation. In this work, polypropylene (PP) was modified on molecular level incorporating poly(ethylene glycol) (PEG) as graft segment (PP-g-PEG) in a range of 6 to 9 mol%. Gold nanoparticles were nucleated in the presence of the copolymer chains via redox reaction. The dissolution of the amphiphilic comb-type graft copolymers containing gold nanoparticles (80 nm in diameter) was achieved in toluene and successfully electrospun from its solution. The diameter of composite fibers was in the range from 0.3 to 2.5 µm. The design of the structurally organized copolymer fiber mats provided a support medium for the nanoparticles enhancing the active surface area for the catalytic applications. The resulting composite fibers exhibited rapid catalytic reduction of methylene blue (MB) dye in the presence of sodium borohydride (NaBH 4) compared to corresponding composite cast film.

This study is carried out on Wistar rats to evaluate the hepatoprotective activity of Argemone
mexicana L aerial part extracts against CCL4 induced acute liver damages. The areal part of the plant was
extracted by methanol and water using soxhlet, rotary evaporator and freeze drying apparatus. Hepatic injury
was achieved by injecting 3 mL/kg s.c. of CCL4 in equal volume proportion with olive oil. The aqueous and
methanol extracts of Argemone mexicana areal part were given at different doses, 100, 200, 400 mg/kg/day
Methanol extract, and 400 mg/kg/day orally of aqueous extract for 5 days under CCL4 induction at 3rd day. The
significance of differences between means was compared among the groups using Independent-sample T-test
with probability value. The methanol extract at 100 mg/kg offered significant hepatoprotective activity (p<0.05)
by reducing the serum marker enzyme, like Serum Glutamate Oxaloacetate Transaminase (SGOT), Serum
Glutamate Pyrovate Transaminase (SGPT) and Alkaline Phosphatase (ALP). Histopathlogical studies further
confirmed the hepatoprotective activity of 100 mg/kg methanol extract. Argemone mexicana L. at dose 100
mg/kg indeed has a reasonable potential in healing liver parenchyma and regeneration of liver cells hence it
may acts as a potent liver tonic. The results obtained were compared with silymarin (70 mg/kg.oral), the
standard drug, which shown recovery toward normalization almost like that of silymarin, therefore, we
recommend for further studies to isolate the pure component and the mechanism that displayed the
hepatoprotective activity for making standard drug.

We report on the preparation of a nanoporous flat electrode by drop casting a nanocomposite consisting of re- duced graphene oxide (rGO) and chitosan onto a polyester substrate. An underlying conductive surface is not required. The nanocomposite was characterized by scanning electron mi- croscopy and electrochemical impedance spectroscopy. The 3D network of the composite was used as a scaffold for the immo- bilization of glucose oxidase (GOx). A well-defined signal re- lated to direct GOx electrochemistry was registered and used to monitor levels of glucose. The resulting biosensor displays a linear response to glucose with a detection limit of 5 μM (at an S/N ratio of 3) and a sensitivity of 41.7 μA⋅mM−1 cm−2. The sensor was applied to the determination of glucose in artificial saliva.

The characterization of the generic processing steps for biosensor devices based on self assembled monolayers SAMs are reviewed from the initial step of examining the surface of an as-received silicon wafer followed by characterisation of layers of organic molecules with biorecognition quality immobilized on the wafer. To investigate these properties various characterisation techniques are considered. An analytical methodology to examine the specific and/or non-specific binding of avidin on biotinylated surfaces is outlined. A wide variety of techniques can be used to interrogate thin films including electrochemical and spectroscopic methods. The principles of operation of techniques are reviewed for each specific characterisation task, eg., AFM for thickness measure, XPS for high resolution structure and mapping contamination of wafer, ToF SIMS for recognition of biomolecules, Raman Spectroscopy and FTIR for identification of compounds, and Surface Plasmon Resonance imaging SPRi for quantification of binding profiles and monitoring affinity interactions in real time. The best approach is combination of techniques such as side by side measurements by mass spectrometry NanoSIMS with AFM that provide complementary topographical information, mapping and distinguish compositional variations. Further development of biosensors relies on combining nanotechnology and molecular biology in reproducibility of patterns of biomolecules on sensing surface of a compact device for ever smaller sample and faster analytical response. Developments of biosensor integrative devices require continuous advances in surface immobilization chemistry, kinetic binding information, improvement of data analysis, and establishment of new standards and methodologies for testing.

Medical devices based on microelectro-mechanical systems (MEMS) platforms are currently being proposed for a wide variety of implantable applications. However, biocompatibility data for typical MEMS materials of construction and processing, obtained from standard tests currently recognized by regulatory agencies, has not been published. Likewise, the effects of common sterilization techniques on MEMS material properties have not been reported. Medical device regulatory requirements dictate that materials that are biocompatibility tested be processed and sterilized in a manner equivalent to the final production device. Material, processing, and sterilization method can impact the final result.

An effective enzymatic glucose biosensorwas developed by immobilizing glucose oxidase on chitosan submicron
particles synthesized from the gladius of Todarodes pacificus (GCSP). The chemically synthesized chitosan from
gladius was pulverized to submicron particles by ball milling technique, which was further characterized and
compared with the standard chitosan (SCS). The degree of deacetylation of GCSP was determined using FTIR
spectroscopy which was comparable to the value of standard chitosan. The glucose oxidase (GOx) was
immobilized over GCSP on porous zinc oxide/platinum nanoparticle (ZnO/Pt) based electrode. The morphological
and structural properties of the electrodes were analyzed using scanning electron microscopy and X-ray diffraction
analysis. The glucose sensing behavior of electrode was estimated using electrochemical analysis and
showed an excellent analytical performance. The electrode ZnO/Pt/GCSP conjugated with GOx displayed high
sensitivity (88.76 μA mM−1 cm−2) with low detection limit in short response time. In addition, the very low
value ofMichaelis–Menten constant for GCSP based electrode contributes a better affinity of the electrode surface
towards glucose oxidase.

The COVID-19 pandemic continues to afflict millions of people without respite. The relentless surge in infections is due to insufficient supplies of appropriate vaccines, the long incubation period and high prevalence of SARS-CoV-2, and the lack of widespread detection and diagnosis. The development of low-cost rapid detection and sensing platforms will prove vital in the race to efficiently detect and diagnose COVID-19. Nanomaterial-based biosensors and detectors are particularly promising in this regard, with the potential to play a significant role in inhibiting the spread of COVID-19 by early detection. In this review, various schemes for the detection and diagnosis of COVID-19 are elaborated, with special emphasis on the unique advantages of nanomaterials for these niche applications. Moreover, smart nanomaterials, i.e., nanomaterials that respond to external stimuli by changing their physicochemical properties, are reviewed and evaluated for novel applications related to COVID-19 detection and diagnosis. The prospects of the reviewed materials and systems are discussed in detail, and a roadmap for future research and development is proposed.

A novel ferrocene-functionalized reduced graphene oxide (rGO)-based electrode is proposed. It was fabricated by the drop casting of ferrocene-functionalized graphene onto polyester substrate as the working electrode integrated within screen-printed reference and counter electrodes. The ferrocene- functionalized rGO has been fully characterized using FTIR, XPS, contact angle measurements, SEM and TEM microscopy, and cyclic voltammetry. The XPS and EDX analysis showed the presence of Fe element related to the introduced ferrocene groups, which is confirmed by a clear CV signal at ca. 0.25 V vs. Ag/ AgCl (0.1 KCl). Mediated redox catalysis of H2O2 and bio-functionalization with glucose oxidase for glucose detection were achieved by the bioelectrode providing a proof for potential biosensing applications.

A new unsymmetrical zinc(II) phthalocyanine (ZnPc2) bearing one EDOT group was efficiently
synthesized as a monomer through the statistical condensation reaction. The other products of mixed
cyclotetramerization ZnPc1, ZnPc3 and ZnPc4 were also isolated. Obtained ZnPc2 is a good precursor
for the synthesis of new functional linear electropolymers. This was approved by the successful
electrochemical copolymerization reaction between ZnPc2 and SNS type monomer HKCN in which the
amino group was desired for the enzyme immobilization. The electrochromic and glucose sensing
properties of copolymer P(ZnPc2-co-HKCN) obtained by electrochemical oxidative polymerization
were investigated. Based on spectroelectrochemical studies, the P(ZnPc2-co-HKCN) copolymer
showed a greenish yellow colour in the reduced state and a dark blue colour in the oxidized state as a
film. An optical contrast ratio of 44% at 471 nm was achieved with a fast switching time (2.5 s).
Meanwhile, the novel biosensor constructed from P(ZnPc2-co-HKCN) showed a linear amperometric
response to glucose within a concentration range of 0.1 mM to 1.5 mM (LOD: 0.049 mM). These data
illustrate the possible use of the P(ZnPc2-co-HKCN) modified electrode as an amperometric glucose
sensor

In this study, a disposable screen-printed gold electrode
(SPGE) utilized of silicon nanowires (SiNWs) and gold nanoparticles as
sensing material was fabricated for detection of DNA oligomers related
to dengue virus. Firstly, SiNWs/AuNPs-SPGE was developed by the
dispersion of SiNWs in 3-Aminopropyltriethoxysilane (APTES, 0.5 %)
onto bare SPGE. Secondly, the AuNPs decoration on SiNWs-SPGE
surface was functionalized using dithiopropionic acid (DTPA) through a
self-assembly monolayer (SAM) technique. The electrochemical response
of methylene blue (MB) as a redox indicator towards synthetic DNA
oligomer after hybridization on SiNWs/AuNPs-SPGE was recorded by
cyclic voltammetry (CV) and differential pulse voltammetry (DPV)
techniques. The results demonstrated that the reduction peak current of
MB was significantly decreased after DNA hybridization process. In
addition, the developed biosensor showed a good storage stability and
could achieve a linear range of 1.0 × 10-11-1.0 × 10-7 M (R= 0.98) with the
detection limit of 1.63× 10-12 M.