Photosensitive Materials Research Articles

Safety and efficacy of a 3D-printed external cranial protection device in preventing complications after unilateral supratentorial decompressive craniectomy: A retrospective cohort study.

The objective was to clarify the feasibility and clinical effect of 3D-printed external cranial protection devices (ECPD) in preventing complications following unilateral supratentorial decompressive craniectomy (DC). A retrospective cohort study was conducted on post-DC patients meeting inclusion and exclusion criteria. In the experimental group, head computed tomography data were collected after DC, and the ECPD were 3D-printed with photosensitive resin materials, and fixed to the bone window defect for continuous wear. The control group received similar postoperative treatment and procedures but did not place the ECPD. Clinical data were collected and analyzed. Forty-four patients were enrolled, 24 in the experimental and 20 in the control group. The incidence of postoperative complications of DC was 84.09%. The median time to initial use of the 3D-printed ECPD was 13.5 days. No patients had skin pressure ulcers, allergies, or wound infections. There were no statistically significant differences between the groups in pre-DC Glasgow Coma Scale scores, post-DC complication rates, or Glasgow Outcome Scale scores at discharge (P > .05). Whereas, there was a statistically significant difference in pre-cranioplasty DC-related complications (P = .027), with a notable reduction in the incidence of subdural effusion in the experimental group (P = .004). The 2 groups had no significant differences in modified Rankin Scale scores after cranioplasty. The clinical use of the 3D-printed ECPD is safe and reliable, effectively reducing the incidence of complications following DC, particularly in the prevention and treatment of subdural effusion. However, it does not significantly improve the prognosis of patients after DC, warranting further research.

A universal strategy to design recyclable photocrosslinked networks via architecting lignin-derived spiro diacetal trigger

Precise transformation of renewable resources into high-performance photo-crosslinked resins with degradability remains a daunting challenge. In this work, we employed a renewable bioresource, lignin-derived vanillin, to construct a rigid spiro diacetal trigger, which was further coupled with thermosetting epoxy segments to develop three high-performance functionalized polymers. Several high-performance photosensitive materials with alkali-dissolving patterning and recyclable were innovatively engineered based on these polymers. The introduction of rigid spiro diacetal triggers, which function through a unique degradable mechanism under mildly acidic conditions, is expected to address the “seesaw” issue between high performance and degradability in photo-crosslinked networks. More importantly, the effect of spiro diacetal trigger on the thermo-mechanical properties and photopolymerization kinetics of thus-obtained photosensitive resins was systematically investigated. Consequently, the glass transition temperature and mechanical properties of the spiro diacetal-tailored naphthalene-type photosensitive resin (P-VPNE) are comparable to, or even exceed, those of competing materials. This work provides a universal strategy and valuable insights for the design and synthesis of high-performance degradable electronic packaging coatings, which are essential for a wide range of revolutionary technologies based on lignin derivatives.

Application of infrared and near-infrared photosensitive pi-conjugated materials in the diagnosis and rehabilitation of sports injuries in aerobics

According to a survey in 2021, around 12% of people were injured during the exercise, and they require the immediate healing process. Several tissue healing materials are incorporated into the sports rehabilitation process. However, the materials have a high rejection reaction rate, poor effect, and low healing speed, which affects aerobics rehabilitation training. The research difficulties are overcome by applying infrared and near-infrared photosensitive pi-conjugated materials to tissue healing procedures to maximize the result of sports rehabilitation. The research analysis discusses the conjugated materials composition and biocompatibility properties which helps to manage the skin healing drug release rate and durations. In addition, the pi-conjugated materials having a high Nearer-Infrared (NIR) observation rate between 600 nm to 1000nm then the materials are suitable for the photobiomodulation therapy wavelength. Then, NIR triggers the drug release from conjugated materials that are used to locate the injured area for treatment and rehabilitation process. Therefore, infrared and NIR-based conjugated materials effectively support injury rehabilitation and damaged tissue regeneration processes. The system efficiency is evaluated using various skin healing rates with different experiments and experimental groups.

A Signal‐on Photoelectrochemical Immunosensor Based on Bi2MoO6 Nanosheets for Carcinoembryonic Antigen Analysis

Herein, a Bi <sub>2</sub>MoO <sub>6</sub> nanosheet (BMONS)‐based sensing platform for signal‐on photoelectrochemical (PEC) detection of carcinoembryonic antigen (CEA) was successfully constructed by employing an enzyme‐catalyzed reaction as the signal amplification method. Specifically, as the CEA concentration escalates, a substantial accumulation of immunological complexes was triggered by the interaction between antigens and antibodies, which promptly concentrate glucose oxidase (GOD) within the wells of a 96‐well microplate. These sequestered GOD molecules subsequently catalyze the hydrolysis of glucose to yield H <sub>2</sub>O <sub>2</sub>, an efficient hole scavenger, leading to significant amplification of the PEC response from the photosensitive materials. Under meticulously optimized conditions, a broad linear detection range spanning from 0.05 to 50 ng mL <sup>–1</sup> with a low limit of detection (LOD) of 0.023 ng mL <sup>–1</sup> has been realized for the detection of CEA. This exceptional performance underscores the successful implementation and efficacy of our BMONS‐based PEC sensing platform, which offers promising avenues for sensitive and selective biomarker detection.

Thermal, Optical, and Emission Traits of SM3+-Ion-Doped Fluoride/Chloride/Oxide Glass for Red/Orange Laser Fiber Applications

This study examined spectroscopic, thermal, and other qualities, such as the lasing parameters, of Sm3+-doped glass with the composition 40P2O5–30ZnO–20LiCl–10BaF2. The ellipsometric data were used in a Sellmeier dispersion relation to estimate the refractive index values of the glasses investigated. The measured absorption spectra of the doped glass reveal the presence of various absorption bands assigned to transitions from the 6H5/2 ground state attributed to Sm3+-ion-excited states. We studied the decay of the 4G5/2 level of the Sm3+ ions in the doped glass by analyzing its absorption and emission fluorescence spectra. The Judd–Ofelt hypothesis allowed us to determine that the quantum efficiency of the 4G5/2–6H7/2 transition is high: 96% and 97% for glass doped with 4.05 × 1019 ions/cm−3 and 11 × 1019 ions/cm−3, respectively. Furthermore, this glass exhibits efficient red/orange enhanced spontaneous emission that matches the excitation band of the photosensitizer material used in medical applications.

Fabrication of carbon nanotube neuromorphic thin film transistor arrays and their applications for flexible olfactory-visual multisensory synergy recognition

Abstract Artificial multisensory devices play a key role in human-computer interaction in the field of artificial intelligence (AI). In this work, we have designed and constructed a novel olfactory-visual bimodal neuromorphic carbon nanotube thin film transistor (TFT) arrays for artificial olfactory-visual multisensory synergy recognition with a very low power consumption of 25 aJ for a single pulse, employing semiconducting single-walled carbon nanotubes (sc-SWCNTs) as channel materials and gas sensitive materials, and poly[[4,8-bis[5-(2-ethylhexyl)-2-thienyl]benzo[1,2-b:4,5-b0]dithiophene-2,6-diyl]-2,5-thiophenediyl-[5,7-bis(2-ethylhexyl)-4,8-dioxo-4H,8H-benzo[1,2-c:4,5-c0]dithio-phene-1,3-diyl]] (PBDB-T) as the photosensitive material. It is noted that it is the first time to realize the simulation of olfactory and visual senses (from 280 nm to 650 nm) with the wide operating temperature range (0–150 °C) in a single SWCNT TFT device and successfully simulate the recovery of olfactory senses after COVID-19 by olfactory-visual synergy. Furthermore, our SWCNT neuromorphic TFT devices with a high I On/I Off ratio (up to 106) at a low operating voltage (−2 to 0.5 V) canmimic not only the basic biological synaptic functions of olfaction and vision (such as paired-pulse facilitation, short-term plasticity, and long-term plasticity), but also optical wireless communication by Morse code. The proposed multisensory, broadband light-responsive, low-power synaptic devices provide great potential for developing AI robots to face complex external environments.

Direct near-infrared laser ignition of CL-20 by introducing DATNBI as a bi-functional additive: Energetic photosensitizer and self-assembly stimulator

The ignition strategy of energetic materials using low-energy near-infrared (NIR) laser has garnered significant attention due to its enhanced safety and reliability. This study explores the use of a relatively photosensitive but mechanical insensitive energetic material, DATNBI, to facilitate the self-assembly of nano-CL-20 crystals into polycrystalline particles though solvothermal induction, yielding a rough structure conducive to NIR laser ignition. The findings demonstrate that by adjusting the content of DATNBI, it is possible to achieve micro-nano controllable spherical CL-20/DATNBI (C/D) particles, with CL-20 as the primary component and DATNBI as the auxiliary component. The incorporation of DATNBI and the rough surface structure enhance the light absorption of C/D particles in the NIR band. Additionally, the unique synergistic effect between CL-20 and DATNBI during thermal decomposition further promotes NIR laser ignition. As expected, the C/D particles achieved self-sustained combustion and exhibited excellent combustion performance under a 1064 nm laser, which is challenging to be achieved with raw CL-20 or raw DATNBI. Furthermore, the relatively insensitive DATNBI and spherical structure reduced the impact sensitivity of the C/D particles. This multifunctional material strategy, integrating energy, safety environment-friendliness, and laser ignition performance, offers a novel approach for laser ignition of energetic materials.

Recent progress in soft robots: principles, designs, and applications

Abstract With advancements in the manufacturing industry persisting, soft robots have experienced rapid development, progressively emerging as a pivotal focus in the future trajectory of robotic technology. As a new type of robot technology, soft robots have significant differences from traditional robots in terms of principles, driving methods, design control, and other aspects. Here, we sort out and summarize the latest developments in soft robotics. Firstly, typical principles and driving methods were introduced, including rope drive, variable stiffness drive (gas negative pressure, intelligent fluids, etc), electromagnetic drive, and so on. Secondly, the main materials and characteristics of soft robots are analyzed, including hydrogels, shape memory alloys, photosensitive materials, electromagnetic rheological elastomer, biodegradable materials, etc. Then, typical soft robot structures and processing methods were introduced, including fluid static skeleton structures, muscle fluid static skeleton structures, and others. Finally, the problems of soft robots are analyzed, and the future development direction and importance are summarized. This paper highlights the recent progress in smart functional materials, typical biomimetic structures, and assembly methods applicable to soft robots, which is expected to assist the development and advancement of the next generation of soft robots.

Fabrication of bacteriorhodopsin-embedded hydrogel construct for biocompatible photosensitive device

Bacteriorhodopsin (br) is a promising photosensitive material with applications in energy conversion, biosensors, and optoelectronic devices due to its bio-sourced origin and photoelectrical properties. Despite advancements in recent years, the integration of br-based devices necessitates the use of materials with little biocompatibility and fabrication techniques with restricted customizability, limiting potential applications such as optocontrol of cell behavior, implants with 3D patterning for retinal disease treatment, and light-sensitive cell robots. To solve this limitation, this study presents a novel approach by embedding br into a hydrogel matrix. It utilizes an extrusion-based and 3D bioprinting technique, showcasing its light-sensitive characteristics within a fully biocompatible construct. The hydrogel, comprising gelatin and sodium alginate, offers excellent printability for generating structured designs with versatile patterns. Photoelectrical properties of the fabricated br-embedded hydrogel construct, such as differential response, light intensity sensitivity, and br concentration sensitivity, are identified through electrochemical characterization. The temporal and spatial pattern recognition ability, based on the photoelectrical characteristics, is demonstrated through modulated light illumination and different patterns of printed hydrogel construct. Pattern recognition ability was then applied to reconstruct images containing different Latin letters. This research presents a novel method for the fabrication of patterned hydrogel constructs with high biocompatibility and distinctive light-responsive properties, expanding the potential applications of br in bio-related scenarios.  

Localized surface plasmon resonance-enhanced photoelectrochemical immunoassay based on high-entropy yolk-shell Au@(ZnCdMnGaCu)xS

The yolk-shell structure has become a research hotspot in the field of photocatalysis in recent years due to its stability, movable yolk, and internal voids. However, yolk-shell has not been fully explored and applied in photoelectrochemical (PEC) immunoassays. In this work, a smartphone-based portable PEC immunoassay was constructed by using high-entropy yolk-shell Au@(ZnCdMnGaCu)xS as a photosensitive material, showing satisfactory detection with the assistance of localized surface plasmon resonance (LSPR). Specifically, a typical sandwich reaction introduces a detection antibody modified and labeled with gold nanoparticles (Au NPs) of alkaline phosphatase (ALP) into the system with the presence of prostate-specific antigen (PSA). Ascorbic acid (AA) content increased with increasing PSA and showed a linear enhancement of photocurrent at PSA concentrations of 0.01–50 ng mL−1 with a limit of detection of 8.94 pg mL−1. Additionally, the proposed assay technology not only provides a portable detection system for the immediate detection of tumor markers, but also offers a promising paradigm for the development of high-entropy materials.

A novel signal-on photoelectrochemical immunosensor based on anthocyanin-sensitized poly(indole-5-carboxylic acid) for ultrasensitive detection of CEA

A signal-on photoelectrochemical (PEC) immunosensor for carcinoembryonic antigen (CEA) detection was constructed using anthocyanin (ACN)-sensitized poly(indole-5-carboxylic acid) (P5ICA) nanofibers as the photoactive material. P5ICA is a p-π conjugated cathode photosensitive material with excellent optical and film-forming properties. P5ICA sensitized with ACN prevents hydrolysis of P5ICA, ensures the stability and further improves the base signal of the PEC immunosensor. The sensitive detection of CEA was achieved by introducing the signaling probe TiO2/In2S3 through biotin-avidin protein specific recognition. ACN-sensitized P5ICA and TiO2/In2S3 exhibit the effective matching of energy levels, which facilitates the separation and transfer of photogenerated e-/h+ pairs and achieves the amplification of PEC signals and the improvement of sensor sensitivity. Under optimal conditions, the range of detection for CEA was 0.01–500 ng mL−1 with lower detection limit of 3.3 pg mL−1. The PEC immunosensor has good stability and high detection sensitivity to CEA. This work provides a novel PEC assay platform for monitoring CEA in real serum samples, which has a promising application in the sensitive detection of tumor markers.

Advantages of Direct Laser Writing for Enhancing the Resolution of Diffractive Optical Element Fabrication Processes

A technology for direct laser writing of code sequences on modulation disks has been developed and implemented, ensuring high accuracy and reliability in the process of forming structural elements. The main advantages of applying direct laser writing compared to contact lithography for forming submicron-sized elements have been demonstrated. The proposed technology is characterized by high resolution and flexibility in configuring the parameters of the optical recording system, making it suitable for a wide range of applications in micro-optics. Direct optical writing is presented as a promising approach for enhancing the resolution of optical systems used in recording submicron-sized diffractive optical elements, as this technology enables the creation of complex optical structures. Additionally, a detailed classification of current approaches for further increasing the resolution of the optical recording system was conducted, including the application of a saturated absorber layer on the photosensitive surface, the use of a laser beam with intensity modeled by a Bessel function, and the synthesis of photosensitive materials with optimized exposure characteristics, ensuring high efficiency and accuracy in the process of direct laser writing.

Target-Triggered Multiple-Polarity-Switchable Multiplexed Photoelectrochemical Platform.

Convenient and accurate quantification of disease-relevant multitargets is essential for community disease screening. However, in the field of photoelectrochemical (PEC) sensors for multisubstance detection, research on the continuous detection of multiple targets using a polarity-switching mode is scarce. In this study, a multiplexed PEC bioassay was developed based on a target-triggered "anodic-cathodic-anodic" multiple-polarity-switchable mode. Employing miRNA-21 and miRNA-141 as model analytes, the photosensitive material combinations of Cu2O/gold nanoparticles (AuNPs)/TiO2 and CdS/AuNPs/TiO2 were successively formed through the specific binding of different whisker branches of Whisker-DNA to Cu2O-H1 and the CdS-tripod DNA ring, respectively. This process reverses the photocurrent polarity from anodic to cathodic and then back to anodic upon detecting different targets, resulting in the high-sensitivity quantification of various biological targets with reduced interference. To enhance the device's utility and affordability in community disease screening, integrating a capacitor and a multimeter-smartphone connection simplifies the assembly and reduces costs. In developing the PEC sensor, the device demonstrated linear detection ranges for miRNA-21 and miRNA-141 from 0.01 fM to 10 nM. Detection limits for miRNA-21 and miRNA-141 were established at 3.2 and 4.3 aM, respectively. The innovative target-triggered multiple-polarity-switchable mode offers adaptability for other multitarget detections by simply modifying the structure of the whisker branches and the combination of photosensitive materials.

Photocatalyst Au@Ni-MOFs with Different Plasmonic Coverages for Improved Hydrogen Evolution from Water.

Plasmonic materials are fundamental photosensitizer materials for photocatalytic reactions. Various structures, including core-shell types, satellite types, and distribution types, have been designed and prepared for the optimization of photocatalytic reactions. However, understanding the profound enhancement mechanism of various structures is still challenging. Thus, the plasmonic coverage is considered to be an index for analyzing the influence mechanism. Here, Au@Ni-MOF core-shell flower sphere-like photocatalysts are prepared, and the size of the flower sphere can be precisely regulated by varying the amount of Au. Thus, different plasmonic coverages are realized through the tuning of spheres of different sizes. The high plasmonic coverage of catalysts can enhance visible light absorption, facilitate the generation of photogenerated electron-hole pairs, and shorten the photogenerated carrier transport distance. Moreover, the exponential relationship between the photocatalytic hydrogen production performance and the plasmonic coverage can also be used as a guide for material design. As a result, a photocatalytic hydrogen production rate of 3389 μmol·g-1·h-1 is achieved in the Au@Ni-MOF sample with high plasmonic coverage, which will advance the plasmonic application in photocatalytic reactions.

Revealing Enhanced Optoelectronic Performance of Sb2Se3‐Based Self‐Sustaining Heterostructures with Bi2Se3 and ZnSe: A Dual Polarity Photo Response

AbstractThrough precise band engineering, Van der Waals heterostructures integration holds great promise for advancing high‐performance optoelectronic devices, especially photodetectors. This study presents self‐sustaining, dual‐polarity, high photo‐responsive heterostrutures (HS) photodetectors based on Sb2Se3, specifically Bi2Se3/Sb2Se3 and ZnSe/Sb2Se3. The Bi2Se3 (ZnSe) layer functions as a channel in a reconfigurable HS phototransistor configuration. These HS devices demonstrate a negative photoconductive response with bias‐modulated polarity switching of the photocurrent. The Bi2Se3/Sb2Se3 device exhibits a responsivity switch from −4 mA W−1 to 0.14 A W−1, while the ZnSe/Sb2Se3 device shows a substantially enhanced responsivity switch from ‐400 mA W−1 to 12 A W−1. This negative photo response results from a photoinduced carrier trapping mechanism at the interface of the channel layer and photosensitizer material. The bias modulation enables the switching from negative to positive responsivity. A comprehensive investigation of photoconductivity modulation provides a deeper understanding of the impact of the photogating effect and trap states under applied bias conditions. Ultrafast transient spectroscopy supports these findings, offering insights into the dynamics of charge carrier relaxation mechanisms and the trapping of photoexcited carriers in defect states, crucial for explaining the dual polarity photo response. These devices present significant advantages for switchable light imaging, optical communication, memory devices, convolution processing, and logic circuits.

Pulsed‐Laser Deposition of Ge‐Doped BiTe Nanofilms and Their Application in Room‐Temperature Long‐Wave Infrared Photodetection

AbstractLong‐wave infrared photodetectors play an indispensable role in a variety of fields such as science, technology, engineering, and medicine. However, to date, most conventional long‐wave infrared photodetectors need to be operated under low temperature to meet the performance requirements. This can lead to a series of problems such as large device volume and high operating cost. Therefore, it is urgent to explore novel long‐wave photosensitive materials. In recent years, the development of nanotechnology has opened a new door for long‐wave infrared photodetection. Herein, pulsed‐laser deposition is successfully applied to the preparation of Ge‐doped BiTe (GBT) thin films. Importantly, the corresponding GBT photodetector exhibits excellent long‐wave infrared photosensitivity. Specifically, upon 10.5 µm illumination, the responsivity, external quantum efficiency, and detectivity reach 1.41 mA W−1, 0.017%, and 1.96 × 106 Jones, respectively. Moreover, a fast response rate with the rise/decay time down to 42.5/41.1 µs is realized. On this basis, the GBT photodetector is used as the receiving unit for optical signals to achieve proof‐of‐concept long‐wave optical information transmission application. On the whole, this study provides a new material platform for long‐wave optoelectronic sensing.

Navigating the frontier: Additive Manufacturing’s role in synthesizing piezoelectric materials for flexible electronics

Additive manufacturing (AM) has significantly transformed the fabrication of functional materials, particularly in electronics and biomedical engineering. This study reviews stereolithography (SLA), selective laser sintering (SLS), fused deposition modeling (FDM), direct ink writing (DIW), and inkjet printing for flexible electronic applications. The review highlights SLA-based 3D printing’s better ability to optimize material compositions, printing procedures, and post-processing methods to improve material characteristics. Photosensitive materials and shrinkage-induced internal tensions seems to be its major constraint. Additionally, SLS 3D printing has improved composite materials' electrical, mechanical, and thermal properties. It has drawbacks including permeable structures and internal tensions. In FDM 3D printing, mechanical and electrical qualities are improved for piezoelectric sensor manufacture. Warping and nozzle blockage require additional study. DIW’s versatility in constructing complicated structures with increased features for energy harvesting and sensor development is also mentioned. We identify ink development and printer nozzle clogging issues. The review concludes that inkjet printing can provide a variety of materials for flexible electronics. Since it integrates the latest discoveries with technological developments, this study may help guide future research and promote innovation in the sector. Overall, additive manufacturing methods provide a new era of sensor technology by offering unrivalled flexibility and versatility.

Evaluation of the cumulative effect of photodynamic therapy and local fluoride on the microhardness and topography of demineralized enamel and cementum surfaces

BackgroundThe present study aimed to determine the cumulative effect of two photodynamic therapy methods with methylene blue and indocyanine green and two topical fluoride therapy methods with fluoride varnish and silver diamine fluoride alone and in combination on the microhardness and topography of demineralized enamel and cementum surfaces. Materials and methodsSeventy-two sound human teeth were selected, and their buccal and lingual surfaces were assigned to two main groups of enamel and cementum using simple randomization. The initial surface hardness (SH) of the enamel and cementum in each sample was determined using a micro-Vickers hardness tester using a 200-g force in 10 s. Then artificial caries was induced by immersion in a demineralizing/remineralizing solution (i.e., each tooth provided two samples, one on the buccal aspect and the other on the lingual aspect). Each enamel/cementum main group was divided into two subgroups using simple randomization based on the local fluoride type (fluoride varnish and silver diamine fluoride) and the type of the photosensitizer agent (methylene blue and indocyanine green). Finally, 16 groups were achieved (n = 9). The final surface hardness of the enamel and cementum samples was determined as described above. Finally, the sample surfaces were prepared for the surface topography evaluation under a scanning electron microscope. The baseline microhardness was compared between the 16 study groups in the first step using one-way ANOVA. Then, three-way ANOVA was used to evaluate the effect of fluoride, laser, and surface (enamel and cementum) on microhardness. ResultsAll the groups exhibited decreased microhardness due to the induction of artificial caries. In both main groups of enamel and cementum, the lowest decrease in microhardness was recorded with combined photodynamic therapy and methylene blue photosensitizer material and fluoride varnish (15.1 % for cementum and 16.7 % for enamel), and the highest decrease in microhardness was recorded in the methylene blue group (35.7 % for cementum and 34.9 % for enamel). ConclusionThe combination of photodynamic therapy with the photosensitizer substance methylene blue or indocyanine green together with fluoride varnish or silver diamine fluoride is effective on the remineralization of demineralized enamel and cementum. Although there is no difference between the combination of photodynamic therapy with fluoride varnish compared to fluoride varnish alone, both of these treatments are more effective than using photodynamic therapy alone.

A self-powered photoelectrochemical aptasensor based on target response and Ag-CdIn2S4 photosensitive material for ultrasensitive detection of prostate-specific antigen

In this study, Ag-CdIn2S4 was selected as a photosensitive material and combined with the zeolite imidazole frame-90 encapsulated methylene blue (ZIF-90@MB) to establish a controlled release system. On that basis, a self-powered photoelectrochemical (PEC) aptasensor was constructed based on target responses to realize the highly sensitive detection of prostate-specific antigen (PSA). The self-powered sensing method was employed to effectively avoid interference from other oxidizing/reducing substances in the system and improve the accuracy of the detection method. The band gap of CdIn2S4 was adjusted by Ag doping, and the visible light absorption capacity and photoelectric conversion efficiency of the material were improved by the local surface plasmon resonance (LSPR) effect of metal Ag. The ZIF-90 porous material was used as a carrier, the MB photosensitizer as a signal molecule was loaded in the ZIF-90 pore channel. The PSA aptamer (PApt) was attached to the ZIF-90@MB surface to form a simple biological gate. In the presence of the PSA, the recognition interaction between PApt and PSA made the biological gate open, then many MB molecules were released from ZIF-90 and enhanced the photocurrent signal. Under the optimal experimental conditions, the linear range of the sensor was 0.005 ∼ 50 ng mL−1, and the detection limit was 2.35 pg mL−1. The accurate determination of PSA in human serum was achieved, which provided a novel sensing strategy for the early diagnosis of clinical biomarkers.

Doped Epoxy Resins as an Alternative to Luminescent Optical Sensors

The main objective of the study was to prepare and then subject to thorough analysis photosensitive materials to determine their usability as materials for the production of special polymer optical fibers. A comparison of the physicochemical properties of compositions containing commercially available fluorescein with compositions doped with 2.7-dihydroxy naphthalene with epichlorohydrin (2.7-NAF.EP) was made. The degree of copolymer conversion, which is one of the most important parameters confirming the effectiveness of the curing method, was calculated based on ATR-FT-IR spectra. Additionally, in order to check the processing capabilities of the obtained compositions, a thorough thermal and spectroscopic analysis was performed (the best method used for this purpose is the coupled analysis technique (TG-DSC-MS)). The obtained results indicate that the photoluminescent properties of the dopants used were not suppressed after their introduction into the matrix. Thermal and spectroscopic analysis allowed us to determine the polymerization conditions in which the physicochemical properties of the obtained materials are the best from the optical fiber-technology point of view.