Physiological Solution Research Articles

Assessing the Impact of Pomegranate Juice on Liver Tissue in Male Rats Exposed to a Commercial Energy Drink

The current study was designed to investigate the effect of pomegranate juice on some biochemical and histological variables resulting from dosing male rats with the energy drink Red Bull. In this study, 28 white male rats were used, divided into four groups, each involving seven animals, according to the following: G1 was given a physiological solution (5 ml/kg) and a standard diet for 120 days; G2 was given a dose of the energy drink Red Bull (volume 1 ml per 100 g); G3 was given pomegranate juice (5 ml/kg) first; then Red Bull; and G4 was given Red Bull first; and after six weeks, he was given pomegranate juice. The results showed that Red Bull consumption significantly elevated RBS, AST, ALT, TC, and TG levels. Pomegranate juice has the ability to reduce the concentration of RBS, AST, ALT, TC, and TG. Histological changes in the liver of animals that were given the Red Bull energy drink were represented by congestion of the central vein, degeneration, and necrosis of liver cells, with severe infiltration of inflammatory cells and a thick wall of the central vein (TW), as well as amyloid (AM) deposition, compared to the negative control group. The results of the histological examination showed that pomegranate juice could repair cellular tissue in the liver and make it similar to the tissue of a control normal group, denoting the possibility of using it in the diet and in treating atherosclerosis and heart disease. Keywords: Pomegranate juice, liver, rats, energy drink, rat model, atherosclerosis, heart disease.

The effect of cone beam computerized tomography voxel size and the presence of root filling on the assessment of middle mesial canals in mandibular molar teeth

IntroductionThe study aims to compare the detection of the middle mesial canal (MMC) in mandibular molar teeth using cone beam computed tomography (CBCT) with different voxel sizes when the mesiobuccal (MB) and mesiolingual (ML) canals have three distinct phases (unpreparation, preparation and obturation and the removal of the obturation and repreparation).MethodsTwo hundred forty-two extracted human mandibular molars were collected and kept in a physiological saline solution prior to use. 0.2-, 0.28- and 0.35-mm voxel sizes CBCT (n = 242) were performed in three phases (Ph): Ph1, no MB and ML canal preparation or obturation; Ph2, after MB and ML canals preparation and obturation; and Ph3, after the removal of the obturation of MB and ML canals and canals repreparation. Images were analyzed using OnDemand3D® software. After the CBCT acquisition in Ph3, all the samples were clarified to visualize the presence of the MMC directly. A blinded, previously calibrated examiner analyzed all the images.ResultsThe MMC was detected in 15 of the 242 teeth after the clearing technique. The lowest MMC detection rate was observed at 0.35-mm voxel size regardless of the ML and MB canal condition, while the highest was observed at 0.2-mm voxel size (P < 0.05). There is no statistically significant difference between 0.2-mm and 0.28-mm voxel sizes (P > 0.05). In all voxel sizes, the highest rate of detectability of the MMC was seen in Phase 1, while the lowest was in Phase 2.ConclusionsIt may be appropriate to take a 0.20-mm voxel size CBCT image, especially after the removal of root canal filling.Clinical relevanceAn appropriate CBCT voxel size and the absence of root canal filling in the root canal system help to detect the missing MMC.

STUDY OF SPECTRAL CHARACTERISTICS OF BOVINE SERUM ALBUMIN UNDER THE EFFECT OF MILLIMETER RANGE ELECTROMAGNETIC WAVES

The study of the effect of millimeter range electromagnetic waves (MM EMW) on bovine serum albumin (BSA) structure at the frequencies both resonant (51.8 GHz) and non-resonant (41.8 GHz) for water has been conducted. The absorption and fluorescence spectra of non-irradiated and irradiated samples of physiological solution and BSA with exposition 60 min were obtained. It was revealed that the spectral characteristics of physiological solution did not change under the effect of MM EMW, while the analogous characteristics of BSA change relevantly. It was also shown that the absorption spectra of the irradiated samples significantly differ from those of non-irradiated protein.

Electrochemical and Theoretical Investigations on the Binding of Anticancer Drug Olaparib to Human Serum Albumin

Abstract This article explores the interaction between Olaparib (OLA), an anticancer drug, and human serum albumin (HSA) on a glassy carbon electrode using cyclic voltammetry and differential pulse voltammetry methods. The study investigates the alterations in the electrochemical behavior of [Fe(CN)6]3–/4– redox pairs in a physiological pH buffer solution due to the OLA-HSA interaction. The electrochemical and kinetic parameters of the redox probe were calculated in the presence of both the drug and protein. Notable variations in these parameters were observed, which can be attributed to the formation of an electro-inactive complex between the protein and drug. The study determined the parameters describing the OLA-HSA complex, including the binding constant and complex stoichiometry. The results revealed the formation of a strong singular drug-albumin complex with a binding constant of 1.12 × 105 M–1. Molecular docking studies supported the experimental findings and provided insights into the binding interactions of OLA with HSA. This study provides valuable insights for future research aimed at enhancing drug delivery systems.

Corrosion protection and antibacterial performance of a chitosan/salicylate coating electrogenerated on a magnesium alloy

In this work, chitosan and chitosan/salicylate coatings were prepared by EPD on AZ91D Mg alloy to improve the corrosion resistance of the substrate in a simulated physiological solution. The effect of two concentrations of salicylate on the morphology and anticorrosive behaviour of the coatings was evaluated. The results showed that the addition of 0.50 g/L sodium salicylate to the chitosan formulation decreased the corrosion rate of the chitosan coating from 0.0025 ± 0.0003 to 0.0007 ± 0.0004 mA cm−2. From the results of electrochemical impedance spectroscopy (EIS) and Fourier Transform Infrared (FTIR) analysis, it can be concluded that the presence of salicylate in the coating leads to a self-healing effect that contributes to an improved corrosion protection. In addition, the presence of salicylate in the coating has been shown to increase antibacterial activity against both Gram-positive and Gram-negative bacteria. It has been demonstrated that salicylate can be released from the coating, which has an anti-inflammatory effect. In this way, a novel chitosan/salicylate coating was developed for the first time on a Mg alloy for bactericidal effect, release of salicylate and corrosion protection in simulated physiological solution. So far, chitosan and salicylate have not been investigated as a combination for the development of multifunctional coatings on Mg alloys. In addition, the self-healing effect of salicylate ions in a chitosan coating was established for the first time.

Electrolyte‐gated organic field‐effect transistors with high operational stability and lifetime in practical electrolytes

AbstractA key component of organic bioelectronics is electrolyte‐gated organic field‐effect transistors (EG‐OFETs), which have recently been used as sensors to demonstrate label‐free, single‐molecule detection. However, these devices exhibit limited stability when operated in direct contact with aqueous electrolytes. Ultrahigh stability is demonstrated to be achievable through the utilization of a systematic multifactorial approach in this study. EG‐OFETs with operational stability and lifetime several orders of magnitude higher than the state of the art have been fabricated by carefully controlling a set of intricate stability‐limiting factors, including contamination and corrosion. The indacenodithiophene‐co‐benzothiadiazole (IDTBT) EG‐OFETs exhibit operational stability that exceeds 900 min in a variety of widely used electrolytes, with an overall lifetime exceeding 2 months in ultrapure water and 1 month in various electrolytes. The devices were not affected by electrical stress‐induced trap states and can remain stable even in voltage ranges where electrochemical doping occurs. To validate the applicability of our stabilized device for biosensing applications, the reliable detection of the protein lysozyme in ultrapure water and in a physiological sodium phosphate buffer solution for 1500 min was demonstrated. The results show that polymer‐based EG‐OFETs are a viable architecture not only for short‐term but also for long‐term biosensing applications.

Minimizing Contact Resistance and Flicker Noise in Micro Graphene Hall Sensors Using Persistent Carbene Modified Gold Electrodes.

Scalable micro graphene Hall sensors (μGHSs) hold tremendous potential for highly sensitive and label-free biomagnetic sensing in physiological solutions. To enhance the performance of these devices, it is crucial to optimize frequency-dependent flicker noise to reduce the limit of detection (LOD), but it remains a great challenge due to the large contact resistance at the graphene-metal contact. Here we present a surface modification strategy employing persistent carbene on gold electrodes to reduce the contact resistivity by a factor of 25, greatly diminishing μGHS flicker noise by a factor of 1000 to 3.13 × 10-14 V2/Hz while simultaneously lowering the magnetic LOD SB1/2 to 1440 nT/Hz1/2 at 1 kHz under a 100 μA bias current. To the best of our knowledge, this represents the lowest SB1/2 reported for scalable μGHSs fabricated through wafer-scale photolithography. The reduction in contact noise is attributed to the π-π stacking interaction between the graphene and the benzene rings of persistent carbene, as well as the decrease in the work function of gold as confirmed by Kelvin Probe Force Microscopy. By incorporating a microcoil into the μGHS, we have demonstrated the real-time detection of superparamagnetic nanoparticles (SNPs), achieving a remarkable LOD of ∼528 μg/L. This advancement holds great potential for the label-free detection of magnetic biomarkers, e.g., ferritin, for the early diagnosis of diseases associated with iron overload, such as hereditary hemochromatosis (HHC).

Flavonoid-rich sesame leaf extract-mediated synthesis of nanozymes: Extraction optimization, chemical composition identification and bioactivity evaluation

Sesame leaves contain rich phenolic acids and flavonoids. However, their potential in nanozyme synthesis has not been investigated yet. Herein, we report the preparation of flavonoid-rich sesame leaf extract (SLE), composition identification, and its use in the construction of iron (Fe)-based nanozymes (Fe-SLE CPNs). SLE was obtained with an extraction yield of ∼14.5% with a total flavonoid content (TFC) of ∼850.85 mg RE/g. There were 83 flavonoid compounds in SLE, primarily including scutellarin, apigenin-7-glucuronid, narcissin, and hyperoside. Fe-SLE CPNs exhibited nanodot morphology with a hydrodynamic size of 79.34 nm and good stability in various physiological solutions, pH levels, and temperatures. The Fe-SLE CPNs were more efficient in the scavenging ability of reactive oxygen species (ROS) than SLE alone. Furthermore, a stronger anti-inflammatory effect of the Fe-SLE CPNs was shown by modulating the MyD88-NF-κB-MAPK signaling pathways. These findings imply that SLE-based nanozymes hold great potential for diverse applications.

Morphological state of lungs of rats under the influence of Vipera berus berus venom

About 5.4 million snake bite cases are registered worldwide every year. About half of them cause 81,000-138,000 deaths or disabled 400,000 people. Despite this, this problem is neglected in many countries in Asia, Africa and Latin America. It is believed that death from snakebites is associated with poverty since the lack of proper access to medical facilities in such sections of the population causes the development of fatal complications. The purpose of the study is to study the morphological state of rats' lungs under exposure to Vipera berus berus venom. Experimental studies were carried out on white, non-linear male rats. Animals were conditionally divided into control and experimental groups, ten individuals each. Experimental rats were injected intraperitoneally with a semi-lethal dose (LD50) (1.576 mg/g-1) of Vipera berus berus venom in a physiological solution. Animals of the control group were injected intraperitoneally with only a physiological solution. Rats were removed from the experiment 24 hours after exposure to the poison and anaesthetized by cervical dislocation. Lung tissue samples were taken for microscopic examination. Fixation of the material and preparation of paraffin blocks were carried out according to generally accepted methods. Staining of histological preparations of the lungs was carried out with hematoxylin and eosin, according to Masson, and the PAS+"Hale" reaction was carried out according to the Mowry method. Histological preparations were studied using an SEO SСAN light microscope. The toxic effect of Vipera berus berus venom caused significant changes in the vascular, stromal and parenchymal components, which was confirmed by histological, histochemical and morphometric data. In the lungs of experimental animals, the vascular bed is primarily restructured, forming coagulopathies and thrombosis. The development of DIC syndrome and haemorrhages accompanies an increase in the permeability of the vessel wall. Inflammatory phenomena are found in the bronchi and respiratory departments' walls. There is a remodelling of the respiratory department components, with the formation of significant areas of dis- and atelectasis and zones of emphysema, which is confirmed morphometrically.

Phosphate/Silicate Ratio Allows for Fine-Tuning of Bioactive Glass Crystallisation and Glass-Ceramic Microstructure

A combination of XRD, solid-state NMR and state-of-the-art imaging techniques were used to investigate how the calcium orthophosphate/calcium silicate ratio affects the crystallisation of bioactive glasses in the system SiO2-P2O5-CaO-CaF2. In the phosphate-free glass, xonotlite, wollastonite and cuspidine crystallised. From 2.4 mol% P2O5, fluorapatite also formed, while the amount of wollastonite decreased. Crystallisation tendency was low for low phosphate contents, while above 3 mol% P2O5 it increased. The phosphate-free glass showed a volume crystallisation mechanism with constant activation energy. By contrast, the glass with the largest phosphate to silicate ratio showed both volume and surface crystallisation, causing a pronounced decrease in activation energy with crystallisation degree. This work shows that by changing the phosphate/silicate ratio we can determine which crystal phases form, obtaining for example fluorapatite-free or wollastonite-free glass-ceramics, depending on the desired application and properties such as mechanical strength or activity in contact with physiological solutions.

ДОСЛІДЖЕННЯ ГІДРОЛІТИЧНОЇ ДЕГРАДАЦІЇ ПОЛІГІДРОКСІАЛКАНОАТІВ І ЇХ СУМІШЕЙ З ПОЛІЛАКТИДАМИ

The hydrolytic degradation of polyhydroxyalkanoates, polylactide and their mixtures in vitro in physiological solution and phosphate-salt buffer as well was researched. The hydrolysis intensity of biopolymers was evaluated via the mass loss, change in molecular weight as well as the water absorption applying the methods of infrared spectroscopy and complex thermal analysis. It was determined that films based on the researched biodegradable polymers thermostated in a phosphate-salt buffer have been degrading faster than in physiological solution.

The Toxic Effects on the Testis of Flutamide vs. Bicalutamide vs. Cyproterone Acetate: An Experimental Rat Study

The aim of this study was to investigate the toxic effects on the rat testis of flutamide, bicalutamide, and cyproterone acetate using histopathological methods. Twenty-four male Sprague-Dawley rats were randomly divided into four groups, control (Group 1), flutamide (Group 2), bicalutamide (Group 3), and cyproterone acetate (Group 4). Physiological saline solution or anti-androgens were administered via oral gavage for 14 days. At the end of the study, the testes were harvested for histological toxic effect scoring. The mean histopathology scores were 0 in Group 1, 0.33 ± 0.81 in Group 2, 1.66 ± 1.36 in Group 3, and 2.93 ± 0.98 in Group 4. The histopathology score in Group 4 was significantly higher than that in Group 1 (p = 0.002), but was not significantly different to those in groups 2 and 3 (p = 0.317 and p = 0.028, respectively). No significant difference was also observed between the other groups. Cyproterone acetate, a steroidal antiandrogen, resulted in significant impairment of testis histology relative to the non-steroidal antiandrogens flutamide and bicalutamide. A non-steroidal agent such as flutamide or bicalutamide should therefore be selected if antiandrogen therapy is to be initiated for reasons such as acne, hirsutism, and paraphilias, particularly in young males.

Valproate intercalated in layered double hydroxides: Synthesis, characterization, release kinetics and biocompatibility studies

Layered double hydroxides (LDHs) are biocompatible materials with excellent anion exchange properties, making them suitable for use as drug carriers by incorporating the drug in its anionic form within their layered structure. In this study, an LDH was synthetized through ion exchange with valproate (VAL), an anticonvulsant drug, using an LDH with nitrate as the parent material. The resulting LDH-VAL sample underwent a comprehensive multi-technique characterization using XRD, TG-DSC, TEM, SEM, EDS, FTIR, XPS and zeta potential measurements. Dissolution kinetics and VAL release kinetics in an ample range of pH (3–9), along with biological assays to test biocompatibility, were also performed. All techniques confirmed the successful intercalation of the drug into the LDH structure, displacing all the nitrate ions of the parent material and increasing the basal spacing d003 from 8.8 Å to 18.3 Å. VAL release in NaCl and physiological buffer solutions was incongruent with LDH dissolution, clearly indicating that VAL release was controlled by an ion exchange process. In 0.9 % NaCl solutions, 90–100 % of VAL was released with only 15–20 % of LDH dissolution, and in buffer solutions 100 % of VAL was released with, at the most, 30 % of LDH dissolution. Biological assays, including lactate dehydrogenase activity, serum calcium concentration and histological analysis of blood samples, confirmed that the prepared LDH-VAL is a biocompatible material with a potential use as a nanodrug carrier.

Control of artificial membrane fusion in physiological ionic solutions beyond the limits of electroformation

Membrane fusion, merging two lipid bilayers, is crucial for fabricating artificial membrane structures. Over the past 40 years, in contrast to precise and controllable membrane fusion in-vivo through specific molecules such as SNAREs, controlling the fusion in-vitro while fabricating artificial membrane structures in physiological ionic solutions without fusion proteins has been a challenge, becoming a significant obstacle to practical applications. We present an approach consisting of an electric field and a few kPa hydraulic pressure as an additional variable to physically control the fusion, enabling tuning of the shape and size of the 3D freestanding lipid bilayers in physiological ionic solutions. Mechanical model analysis reveals that pressure-induced parallel/normal tensions enhance fusion among membranes in the microwell. In-vitro peptide-membrane assay, mimicking vesicular transport via pressure-assisted fusion, and stability of 38 days with in-chip pressure control via pore size-regulated hydrogel highlight the potential for diverse biological applications.

Simultaneous Injection of Contrast and Saline Using Spiral Flow-Generating Tube for Hepatic Dynamic Computed Tomography: Effect on Enhancement of Liver Parenchyma and Metastases to the Liver.

Recently, there have been a few reports regarding the usefulness of a novel saline injection technique using a spiral flow-generating tube. The purpose of this study was to evaluate whether simultaneous saline injection using a spiral flow-generating tube was able to improve hepatic contrast enhancement and lesion conspicuity of metastatic liver tumors. We randomized a total of 411 patients with various liver diseases including metastases by total body weight (A, n = 204) and contrast dilution protocol (B, n = 207). Group A received 400 mgI/kg of contrast medium alone without a spiral flow-generating tube; group B received contrast medium 400 mgI/kg simultaneous with injection of a 0.57-ml/kg physiologic saline solution through a spiral flow-generating tube. Abdominal aorta computed tomography (CT) number, hepatic enhancement (ΔHU), percentage of tests demonstrating an enhancement effect of the liver parenchyma exceeding Δ50 HU in 3 measured segments (S2, S6, and S8), and the contrast-to-noise ratio of the metastatic liver tumors were measured. The mean aortic CT number of group B (417.0 HU ± 61.7; P < 0.01) was approximately 10% higher than that of group A (384.6 ± 79.1 HU). The average ΔHU was 59.8 ± 11.4 HU for group A and 61.7 ± 11.7 for group B. The ΔHU for group B was significantly higher than that for group A (P = 0.017). The percentage of tests demonstrating with the enhancement effect of group B was more than 80% in all subgroups; however, that of group A was less than 80% in all subgroups. The contrast-to-noise ratio of group B (7.8 ± 3.3 HU) was significantly higher compared to that of group A (6.5 ± 2.8 HU) (P < 0.05). Because of the volume effect, injecting a contrast medium diluted with normal saline improved the degree of hepatic and aortic contrast enhancement and achieved better visualization of liver metastases. The use of spiral flow-generating tube may help diagnostic of hepatic and aortic contrast enhancement and liver metastases. The use of a spiral flow-generating tube improved the degree of hepatic and aortic contrast enhancement and achieve better visualization of liver metastases. The use of low-concentration syringe formulations is limited by body weight. However, the use of spiral flow-generating tube provides low-concentration contrast medium regardless of body weight.

Comparative Study on Passive Film Formation Mechanism of Cast and PBF-LB/M-TC4 in Simulated Physiological Solution.

Personalized laser powder bed fusion (PBF-LB/M) Ti-6Al-4V (TC4) has a broader application prospect than that of traditional casting. In this paper, the composition and corrosion resistance of the passive film formation mechanism of TC4 prepared by optimization of PBF-LB/M techniques and traditional casting were systematically studied in 0.9 wt.% NaCl at 37 °C by electrochemical technique and surface analysis. The rates of the passive film formation process, corrosion resistance and composition of TC4 show different characteristics for the different preparation processes. Although the rate of passive film formation of cast-TC4 was higher at the initial immersion, the open circuit potential was more positive, and the film thickness was larger after stabilization, those facts show no positive correlation with corrosion resistance. On the contrary, with no obvious defects on the optimized PBF-LB/M-TC4, the passive film resistance is 2.5 times more, the defect concentration is reduced by 30%, and the TiO2 content is higher than that of the cast-TC4, making the martensitic-based PBF-LB/M-TC4 exhibit excellent corrosion resistance. This also provides good technical support for the further clinical application of PBF-LB/M-TC4.

Compatibility of a New Ocular Surface Dye with Disposable and Bi-Weekly Soft Contact Lenses: An Experimental Study.

Ocular surface staining for assessing corneal and conjunctival epithelium integrity is typically conducted using fluorescein, lissamine green, or rose Bengal dyes. Recently, a novel vital dye, REmark®, based on riboflavin, has been proposed for ocular surface examination. In the management of corneal and ocular surface diseases (OSD), the use of contact lenses is integral to therapeutic strategies. This study explores the compatibility of REmark® with four different types of disposable or bi-weekly soft contact lenses. Morphological variations observed under stereomicroscopy and ultraviolet (UV) ray transmittance in the visible spectrum (VIS) were evaluated at 2 and 4 h post-immersion of the contact lenses in both the original fluid and the new dye. The findings indicate no significant differences between the group treated with the original liquid and those immersed in REmark®, except for a yellow hue observed in the latter group, which dissipates after 8 h in physiological solution. This study highlights the potential of utilizing the new vital dye for ophthalmologic examinations even in the presence of applied soft contact lenses, offering a promising avenue for improved diagnostic practices and patient comfort.

The efficacy of lumbar epidural steroid injections in “failed back surgery syndrome” and lumbar radiculopathy

Aims: Lumbago is one of the common conditions in our present community. Definite periods of human’s life people encountered in the form of usually regressing attacks that %10-%15 of this important condition requires surgical therapy. Cause of wrong diagnosis and treatment Spinal surgery may not always give favourable result. Patients undergone one or more back surgery exist back and/or leg pain which does not improve, is called failed back surgery syndrome. Epidural steroid administration is one of the most invasive method which is used in back pain. Effects and application results are controversial. In this study we aimed to compare the effects of steroid and local anesthetic solutions which administered by epidural way on pain controlling between the patients that have chronic back pain because of lomber radiculopathy, undergone surgery and not surgery. Methods: It was evaluated retrospectively pain controlling effect of administered steroid and local anesthetics by interlaminal epidural way to ASA 1-2-3, between 18-80 aged 40 patient which undergone piror one or plural back surgery and have no surgery between May 2009-December 2009 apply with back pain complaint to İstanbul Education and Research Hospital Algology Department. Patient’s visuel analog scala (VAS) and severity of back pains, before procedure, second week after procedure, fourth week after procedure, sixth week after procedure in either two groups out of ten points was estimated. Results: Totally of 7 ml solution which contains 1 ml triamsinolon asetonid 40 mg/ml (Sinakort-A ampul, İ.E. Ulugay), 3 ml levobupivacaine 5mg/ml ( Chirocaine ampul, Abbott) and 3 ml serum phsiyologic ( % 0,9 NaCl ) administered by epidural way into either two group patients. There were no significant difference between two groups by mean of age, weight, height, BMI and back pain durations. Evaluating the groups into themselves, opioid requirements and VAS scores before injection was markedly higher than 2,4 and 6. week scores in either two groups (p&lt;0.05). There was no statistically significant difference when we compare into groups of 2,4 and 6. week opioid requirements and VAS scores in either two groups. All patient manifested their pleasure and there was no complication occured. Conclusion: Consequently; it was thought that epidural administration of steroid (triamsinolon) ,local anesthetics (levobupivacaine) and serum physiologic solution was effective especially on early back pain treatment, also safe method and beneficial to patient satisfaction in the patients who has failed back surgery and chronic back pain.

Zinc-Substituted Hemoglobin-Albumin Cluster as a Porphyrin-Carrier for Enhanced Photodynamic Therapy.

Apohemoprotein is focused on the field of theranostics, serving as a porphyrin carrier. Hemoglobin (Hb) consists of α2β2 tetramer with iron(II)-protoporphyrin IX (heme) bound to each globin. However, heme-removed Hb (apoHb) causes dissociation at αβ interfaces and aggregation under physiological conditions. We synthesized a stable apoHb derivative comprising intramolecular-crosslinked apoHb (apoXHb) and human serum albumin (HSA), apoXHb-HSA3. ApoXHb-HSA3 engendered no aggregates in the physiological solutions. Moreover, apoXHb-HSA3 was reconstituted with zinc(II)-protoporphyrin IX (ZnP), generating ZnXHb-HSA3, a potent photosensitizer for photodynamic therapy (PDT). The photophysical properties of ZnXHb-HSA3 were identical to those of zinc-substituted XHb (ZnXHb). Cellular uptake behavior was evaluated using various cancer cell lines. ZnXHb-HSA3 released ZnP around the cells, and the free ZnP penetrated cell membranes. In contrast, protein units were not observed within the cells. ZnXHb-HSA3 showed no cytotoxicity under dark conditions and demonstrated superior PDT activity in comparison to naked ZnXHb. ZnXHb-HSA3 acts as an innovative porphyrin carrier for enhanced PDT.

Carbon Nanotube-Based Printed All-Organic Microelectrode Arrays for Neural Stimulation and Recording.

In this paper, we report a low-cost printing process of carbon nanotube (CNT)-based, all-organic microelectrode arrays (MEAs) suitable for in vitro neural stimulation and recording. Conventional MEAs have been mainly composed of expensive metals and manufactured through high-cost and complex lithographic processes, which have limited their accessibility for neuroscience experiments and their application in various studies. Here, we demonstrate a printing-based fabrication method for microelectrodes using organic CNT/paraffin ink, coupled with the deposition of an insulating layer featuring single-cell-sized sensing apertures. The simple microfabrication processes utilizing the economic and readily available ink offer potential for cost reduction and improved accessibility of MEAs. Biocompatibility of the fabricated microelectrode was suggested through a live/dead assay of cultured neural cells, and its large electric double layer capacitance was revealed by cyclic voltammetry that was crucial for preventing cytotoxic electrolysis during electric neural stimulation. Furthermore, the electrode exhibited sufficiently low electric impedance of 2.49 Ω·cm2 for high signal-to-noise ratio neural recording, and successfully captured model electric waves in physiological saline solution. These results suggest the easily producible and low-cost printed all-organic microelectrodes are available for neural stimulation and recording, and we believe that they can expand the application of MEA in various neuroscience research.