Real‐Time Detection of Fibrinogen via Imprinted Recognition Sites

Nanoparticle-assisted plasmonic sensors: Recent developments in clinical applications

Nanotechnology is an important science that finds a wide range of applications from energy production to industrial production processes and biomedical applications. Nanoparti-cles, which are the most frequently preferred nanomaterials that form the basis of nanotechnolo-gy, are prepared with different composition, size, shape and surface chemistry to provide new techniques in applications in many different fields. The use of nanoparticles in the preparation of plasmonic sensors has increased the interest in plasmonic sensors such as surface plasmon resonance, electrochemical sensors, surface enhanced raman scattering and colorimetric sensors due to their increased sensing capacity on sensor surfaces. Plasmonic sensors are an important option in many different fields, such as medicine, environmental agriculture and food safety, thanks to their ability to solve a multitude of challenges. Because, plasmonic sensors are defined as sensing devices with important features such as sensitive and fast detection, no need for labels, real-time analysis, portability. In this review, the information about nanoparticles and their types and working principles of plasmonic sensors is given. Then, examples in clinical applications using different plasmonic sensors prepared with plasmonic nanoparticles are discussed in detail.

Advancements in biosensor technologies for fibrinogen detection in cardiovascular disorders

Rapid and accurate identification of cardiovascular diseases (CVDs) are crucial for timely medical interventions and improved patient outcomes. Fibrinogen (Fib) has emerged as a valuable biomarker for CVDs, playing a significant role in their early detection. Elevated levels of Fib are associated with an increased risk of developing CVD, highlighting its importance for more precise diagnosis and effective treatment strategies. In recent years, significant advancements have been made in developing biosensor-based approaches for detecting Fib, offering high sensitivity and specificity. This review aims to explore the impact of Fib on cardiovascular conditions, assess the current advancements, and discuss the future potential of biosensors in Fib research for diagnosing cardiovascular disorders. Furthermore, we evaluate various biosensor techniques, including optical, electrochemical, electronic, and gravimetric methods, in terms of their utility for measuring Fib in clinical samples such as serum, plasma, whole blood, and other body fluids. A comparative analysis of these techniques is conducted based on their performance characteristics. By providing a comprehensive overview of the relationship between Fib and cardiovascular ailments, this review aims to clarify the advancements in biosensor technology for Fib detection. The comparison of different biosensor techniques will aid researchers and clinicians in selecting the most suitable approach for their specific diagnostic needs. Ultimately, integrating biosensors into clinical practice has the potential to revolutionize the detection and management of CVDs, leading to improved patient care and outcomes.

Development of Optical-Based Molecularly Imprinted Nanosensors for Adenosine Detection

Adenosine nucleoside is an important molecule in human physiology. The levels of adenosine nucleoside in urine and plasma are directly or indirectly related to diseases such as neurodegenerative diseases and cancer. In the present study, adenosine-imprinted and non-imprinted poly(2-hydroxyethyl methacrylate-methacrylic acid) (poly(HEMA-MAA)) surface plasmon resonance (SPR) nanosensors were prepared for the determination of adenosine nucleoside. First, MAA/adenosine pre-polymerization complexes were prepared at different molar ratios using adenosine as a template molecule and methacrylic acid (MAA) as a monomer, and SPR nanosensor surfaces were optimized by determining the highest imprinting factor of the chip surfaces. The surfaces of adenosine-imprinted and non-imprinted SPR nanosensors were characterized by using atomic force microscopy, ellipsometry, and contact angle measurements. Kinetic analyses were made with different concentrations in the range of 0.5-400.0 nM for the detection range with a pH 7.4 phosphate buffer solution. The limit of detection in adenosine aqueous solutions, artificial plasma, and artificial urine was determined to be 0.018, 0.015, and 0.013 nM, respectively. In the selectivity analysis of the developed nanosensors, the selectivity of adenosine SPR nanosensors in solutions at different concentrations was determined by using guanosine and cytidine nucleosides. The relative selectivity coefficients of adenosine-imprinted SPR nanosensors for adenosine/cytidine and adenosine/guanosine are 3.836 and 3.427, respectively. Since adenosine-imprinted SPR nanosensors are intended to be used in medical analysis and research, adenosine analysis has also been studied in artificial urine and artificial plasma samples.

Tunable surface plasmon resonance enhanced fluorescence via the stretching of a gold quantum dot-coated aluminum-coated elastomeric grating substrate

In this study, the surface plasmon resonance (SPR)-enhanced fluorescence properties of gold quantum dots (AuQDs) on an aluminum (Al)-coated polydimethylsiloxane (PDMS) grating substrate were investigated by changing the grating pitch via mechanical stretching. The SPR-excitation wavelength of the AuQDs/Al-coated PDMS-grating substrate was tuned by changing the incident light angle from 5° to 60° and stretching it from 0 to 1.0 mm. In addition, the SPR-enhanced fluorescence tuning ability was studied using an AuQD/Al-coated PDMS-grating film by stretching the substrate. The SPR-enhanced fluorescence (SPF) of the AuQDs on the Al-grating was observed using a violet laser as the excitation source at 405 nm with p-polarization. The wavelengths of the SPR excitation, corresponding to the SP-dispersion mode of +1, were shifted to a longer wavelength upon stretching the grating substrate from 0 to 1.0 mm. By stretching the AuQDs/Al-grating PDMS substrate, the SPR-enhanced fluorescence intensity increased at fixed incident angles of 15° and 35°, whereas the SPR-enhanced fluorescence intensity decreased at 40°. Moreover, the SPF could be tuned to exhibit different properties in tunable optical sensors.