Interdigitated Electrode Biosensor Based on Plasma-Deposited TiO2 Nanoparticles for Detecting DNA

The Role of Interdigitated Electrodes in Printed and Flexible Electronics

Flexible electronics, also referred to as printable electronics, represent an interesting technology for implementing electronic circuits via depositing electronic devices onto flexible substrates, boosting their possible applications. Among all flexible electronics, interdigitated electrodes (IDEs) are currently being used for different sensor applications since they offer significant benefits beyond their functionality as capacitors, like the generation of high output voltage, fewer fabrication steps, convenience of application of sensitive coatings, material imaging capability and a potential of spectroscopy measurements via electrical excitation frequency variation. This review examines the role of IDEs in printed and flexible electronics since they are progressively being incorporated into a myriad of applications, envisaging that the growth pattern will continue in the next generations of flexible circuits to come.

Conductometric immunosensor for specific Escherichia coli O157:H7 detection on chemically funcationalizaed interdigitated aptasensor

Escherichia coli O157:H7 is a strain of Escherichia coli known for causing foodborne illness through the consumption of contaminated or raw food. To detect this pathogen, a conductometric immunosensor was developed using a conductometric sensing approach. The sensor was constructed on an interdigitated electrode and modified with a monoclonal anti-Escherichia coli O157:H7 aptamer. A total of 200 electrode pairs were fabricated and modified to bind to the target molecule replica. The binding replica, acting as the bio-recognizer, was linked to the electrode surface using 3-Aminopropyl triethoxysilane. The sensor exhibited excellent performance, detecting Escherichia coli O157:H7 in a short time frame and demonstrating a wide detection range of 1 fM to 1 nM. Concentrations of Escherichia coli O157:H7 were detected within this range, with a minimum detection limit of 1 fM. This innovative sensor offers simplicity, speed, high sensitivity, selectivity, and the potential for rapid sample processing. The potential of this proposed biosensor is particularly beneficial in applications such as drug screening, environmental monitoring, and disease diagnosis, where real-time information on biomolecular interactions is crucial for timely decision-making and where cross-reactivity or interference may compromise the accuracy of the analysis.

A Review on the Progress of Optoelectronic Devices Based on TiO2 Thin Films and Nanomaterials

Titanium dioxide (TiO₂) is a kind of wide-bandgap semiconductor. Nano-TiO₂ devices exhibit size-dependent and novel photoelectric performance due to their quantum limiting effect, high absorption coefficient, high surface-volume ratio, adjustable band gap, etc. Due to their excellent electronic performance, abundant presence, and high cost performance, they are widely used in various application fields such as memory, sensors, and photodiodes. This article provides an overview of the most recent developments in the application of nanostructured TiO₂-based optoelectronic devices. Various complex devices are considered, such as sensors, photodetectors, light-emitting diodes (LEDs), storage applications, and field-effect transistors (FETs). This review of recent discoveries in TiO₂-based optoelectronic devices, along with summary reviews and predictions, has important implications for the development of transitional metal oxides in optoelectronic applications for researchers.

Surface modification of TiO2 nanoparticles with organic molecules and their biological applications

In recent years, titanium(IV) dioxide nanoparticles (TiO₂NPs) have shown promising potential in various biological applications such as antimicrobials, drug delivery, photodynamic therapy, biosensors, and tissue engineering. For employing TiO₂NPs in these fields, their nanosurface must be coated or conjugated with organic and/or inorganic agents. This modification can improve their stability, photochemical properties, biocompatibility, and even surface area for further conjugation with other molecules such as drugs, targeting molecules, polymers, etc. This review describes the organic-based modification of TiO₂NPs and their potential applications in the mentioned biological fields. In the first part of this review, around 75 recent publications (2017-2022) are mentioned on the common TiO₂NP modifiers including organosilanes, polymers, small molecules, and hydrogels, which improve the photochemical features of TiO₂NPs. In the second part of this review, we presented 149 recent papers (2020-2022) about the use of modified TiO₂NPs in biological applications, in which specific bioactive modifiers are introduced in this part with their advantages. In this review, the following information is presented: (1) the common organic modifiers for TiO₂NPs, (2) biologically important modifiers and their benefits, and (3) recent publications on biological studies on the modified TiO₂NPs with their achievements. This review shows the paramount significance of the organic-based modification of TiO₂NPs to enhance their biological effectiveness, paving the way toward the development of advanced TiO₂-based nanomaterials in nanomedicine.

Type 1 Diabetes Mellitus: A Review on Advances and Challenges in Creating Insulin Producing Devices

Type 1 diabetes mellitus (T1DM) is the most common autoimmune chronic disease in young patients. It is caused by the destruction of pancreatic endocrine β-cells that produce insulin in specific areas of the pancreas, known as islets of Langerhans. As a result, the body becomes insulin deficient and hyperglycemic. Complications associated with diabetes are life-threatening and the current standard of care for T1DM consists still of insulin injections. Lifesaving, exogenous insulin replacement is a chronic and costly burden of care for diabetic patients. Alternative therapeutic options have been the focus in these fields. Advances in molecular biology technologies and in microfabrication have enabled promising new therapeutic options. For example, islet transplantation has emerged as an effective treatment to restore the normal regulation of blood glucose in patients with T1DM. However, this technique has been hampered by obstacles, such as limited islet availability, extensive islet apoptosis, and poor islet vascular engraftment. Many of these unsolved issues need to be addressed before a potential cure for T1DM can be a possibility. New technologies like organ-on-a-chip platforms (OoC), multiplexed assessment tools and emergent stem cell approaches promise to enhance therapeutic outcomes. This review will introduce the disorder of type 1 diabetes mellitus, an overview of advances and challenges in the areas of microfluidic devices, monitoring tools, and prominent use of stem cells, and how they can be linked together to create a viable model for the T1DM treatment. Microfluidic devices like OoC platforms can establish a crucial platform for pathophysiological and pharmacological studies as they recreate the pancreatic environment. Stem cell use opens the possibility to hypothetically generate a limitless number of functional pancreatic cells. Additionally, the integration of stem cells into OoC models may allow personalized or patient-specific therapies.

TiO2-DNA Nanosensor In Situ for Quick Detection of Nasal Flora in Allergic Rhinitis Patients

Background

A relevant study found that allergic rhinitis (AR) may be related to the imbalance of nasal flora. Therefore, if the nasal flora of AR patients can be detected quickly, it is of great significance to study the distribution law of nasal flora in AR patients and explore its correlation with AR.

Objective

To design a new and convenient nano-DNA sensor for quick screening of nasal flora in allergic rhinitis (AR) patients, so as to provide experimental basis for the prevention and treatment of AR.

Methods

We create a synthesized nanostructured DNA biosensor called Nano-TiO₂-DNA sensor which can be combined with samples from nasal mucosa or secretion with high efficiency and detect certain flora in situ without DNA extraction or RNA sequencing. In a physical property test, firstly, we tested the permeability, solubility, and storage temperature of nano-TiO₂, so as to provide experimental basis for the synthesis of Nano-TiO₂-DNA sensor. Subsequently, the permeability of Nano-TiO₂-DNA sensor in Staphylococcus aureus was further tested. In a clinical experiment, we selected 60 AR patients treated in our hospital from September 2020 to September 2021 as the AR group and 60 healthy people who underwent physical examination at the same time as the control group. The Nano-TiO₂-DNA sensor was used to detect typical nasal flora in AR patients, and Pearson's correlation analysis was used to explore the correlation between nasal flora with serum IgE and eosinophils.

Results

As for physicochemical characteristics, this sensor can permeate into certain bacteria directly and specifically. It has high affinity ability with a target, and the combination can be detected by evaluating the released fluorescence qualitatively and quantitatively. It can be stored at −20°C in ethyl alcohol stably. By this sensor, we have successfully detected Staphylococcus aureus, Klebsiella pneumoniae, and viridans streptococci in AR patients compared with healthy people, which will help these patients in the prevention of acute sinusitis and acute or subacute pneumonia. Furthermore, we found Proteus had the strongest positive correlation with AR while Actinomyces had the biggest negative correlation.

Conclusion

The Nano-TiO₂-DNA sensor will help an outpatient doctor more for quick screening certain nasal flora in AR patients and improve the prevention of AR-related complications.

Broad-Spectrum Theranostics and Biomedical Application of Functionalized Nanomaterials

Nanotechnology is an important branch of science in therapies known as “nanomedicine” and is the junction of various fields such as material science, chemistry, biology, physics, and optics. Nanomaterials are in the range between 1 and 100 nm in size and provide a large surface area to volume ratio; thus, they can be used for various diseases, including cardiovascular diseases, cancer, bacterial infections, and diabetes. Nanoparticles play a crucial role in therapy as they can enhance the accumulation and release of pharmacological agents, improve targeted delivery and ultimately decrease the intensity of drug side effects. In this review, we discussthe types of nanomaterials that have various biomedical applications. Biomolecules that are often conjugated with nanoparticles are proteins, peptides, DNA, and lipids, which can enhance biocompatibility, stability, and solubility. In this review, we focus on bioconjugation and nanoparticles and also discuss different types of nanoparticles including micelles, liposomes, carbon nanotubes, nanospheres, dendrimers, quantum dots, and metallic nanoparticles and their crucial role in various diseases and clinical applications. Additionally, we review the use of nanomaterials for bio-imaging, drug delivery, biosensing tissue engineering, medical devices, and immunoassays. Understandingthe characteristics and properties of nanoparticles and their interactions with the biological system can help us to develop novel strategies for the treatment, prevention, and diagnosis of many diseases including cancer, pulmonary diseases, etc. In this present review, the importance of various kinds of nanoparticles and their biomedical applications are discussed in much detail.