The Role of Rosmarinic Acid on the Bioproduction of Gold Nanoparticles as Part of a Photothermal Approach for Breast Cancer Treatment

Breast cancer is a high-burden malignancy for society, whose impact boosts a continuous search for novel diagnostic and therapeutic tools. Among the recent therapeutic approaches, photothermal therapy (PTT), which causes tumor cell death by hyperthermia after being irradiated with a light source, represents a high-potential strategy. Furthermore, the effectiveness of PTT can be improved by combining near infrared (NIR) irradiation with gold nanoparticles (AuNPs) as photothermal enhancers. Herein, an alternative synthetic method using rosmarinic acid (RA) for synthesizing AuNPs is reported. The RA concentration was varied and its impact on the AuNPs physicochemical and optical features was assessed. Results showed that RA concentration plays an active role on AuNPs features, allowing the optimization of mean size and maximum absorbance peak. Moreover, the synthetic method explored here allowed us to obtain negatively charged AuNPs with sizes favoring the local particle accumulation at tumor site and maximum absorbance peaks within the NIR region. In addition, AuNPs were safe both in vitro and in vivo. In conclusion, the synthesized AuNPs present favorable properties to be applied as part of a PTT system combining AuNPs with a NIR laser for the treatment of breast cancer.

Color and antibacterial activity of annatto extracts at various pH of distilled water solvent and extraction temperature

Annato (Bixa orrelana L.) has been renowned as a tropical plant rich in carotenoid pigments such as nonpolar bixin and polar norbixin. This study was aimed to obtain natural colorant and antimicrobials from annatto extracts. The extraction was carried out by maceration for 10 mins using distilled water as the extraction solvent at various pH and extraction temperatures. The variations of solvent pH used in this research were 4, 7, and 9, while that of extraction temperatures were 70, 80, and 90oC. The potential of annatto extract as an antimicrobial agent was tested by analyzing the extract's ability to inhibit pathogens and its phytochemical compounds. Escherichia coli and Staphylococcus aureus were used as the pathogenic bacteria by using the agar diffusion method. The color of annatto extracts was measured using Munsel Chard to determine the level of hue (color), value (brightness), and chroma (intensity), as well as maximum absorbance. The results showed that all extracts have the potential to inhibit E. coli and S aureus (weak-moderate). The observed annatto extracts had different color intensities as indicated by the hue, value, and chroma and a maximum absorbance at a wavelength of 400 nm.

Stability of Curcumin Improved in Hydrophobic Based Deep Eutectic Solvents

Turmeric is a commonly known natural spice that contains many phytoconstituents. Among which Curcumin is a polyphenol present in turmeric responsible for many pharmacological actions. Curcumin is still used as a traditional medicine in fields such as Ayurvedic, Siddha, and Unani. Though Curcumin has a large number of activities, it has disadvantages, such as small shelf life due to poor chemical stability, poor absorption results in less bioavailability, less water solubility, rapid metabolism results in quick elimination from the systemic circulation. A Deep eutectic solvent (DES) is a new class of solvents. Hydrophobic DES can be used for dissolving water-insoluble compounds. DES can be prepared when two solid components mixed in a particular proportion are converted into liquid. DES can be used as a solvent for dissolving water-insoluble compounds and to increase the stability. In this work initially, curcumin linearity studies were conducted in different buffers. A buffer showing maximum absorbance was selected from the linearity studies. Then, DES was prepared by combining Camphor:Menthol (1:1) (CM-DES), Camphor:Thymol (1:1) (CT-DES) and, Menthol:Thymol (1:1) (MT-DES). The stability of curcumin in different DES was determined from the stock and working solutions in benchtop condition (room temperature) and, refrigerator condition (5±3°C). Only working solution stability was determined in the in vitro media temperature (37±2°C). From this study, it was concluded that 50 mM Sodium dihydrogen orthophosphate with 0.5% SLS at pH 5.5 showed maximum absorbance value compared with other buffers, so it was selected for further studies. From stability studies, it was found that curcumin in CM-DES was found to be stable in both stock and working solutions compared to the other two CT-DES and MT-DES.

Effect of Different Process Parameters on the formation of Silver Nanoparticles using Crude and Modified Neem (Azadirachta indica) Leaf Extracts

In recent times, the biosynthesis of nanoparticles, which has led to significant growth in the field of nanotechnology. The use of plant extracts has become an impetus in this field as it is a simple and eco-friendly method. This study was an attempt to study different parameters in biosynthesis of silver nanoparticles using Azadirachta indica (Neem) leaf extracts. Four different process parameters such as concentrations of neem leaf extract, types of neem leaf extract, mixing ratios and the reaction time period were investigated on the formation of silver nanoparticles. Initially, the formation of silver nanoparticles was detected by the visual observation. Then, the synthesized silver nanoparticles were characterized using UV-Visible spectroscopy and scanning electron microscopy (SEM). The change of color from yellow to reddish brown color confirmed the formation of silver nanoparticles. The silver surface plasmon resonance (SPR) band obtained in the expected visible range of UV-Visible spectroscopy confirmed the synthesis of the nanoparticles. SEM images showed that silver nanoparticles are roughly spherical and of uniform particle size, and the average particle size is 100 nm. Further, the maximum absorbance of SPR band was considerably varied with different process parameters used in the present study. The UV-Visible spectra of 2.5 g/100 mL of crude neem leaf extract without any dilution showed maximum absorbance in the expected range with the mixing ratio of (Neem and AgNO3) 1:8. However, the maximum absorbance of modified neem leaf extracts (pH 10) resulted lower in value than the crude extracts in the 20 times diluted sample with the mixing ratio of 1:9. Moreover, modified extract with UV radiation exposure increased the absorbance in the expected visible range. It concludes that fine tuning of the bioprocess parameters would enhance nanoparticle synthesis.

Identifying the chloroperoxyl radical in acidified sodium chlorite solution

The present study identified the active radical species in acidic sodium chlorite and investigated the feasibility of quantifying these species with the diethylphenylenediamine (DPD) method. Electron spin resonance (ESR) spectroscopy was used to identify the active species generated in solutions containing sodium chlorite (NaClO2). The ESR signal was directly observed in an acidified sodium chlorite (ASC) aqueous solution at room temperature. This ESR signal was very long-lived, indicating that the radical was thermodynamically stable. The ESR parameters of this signal did not coincide with previously reported values of the chlorine radical (Cl●) or chlorine dioxide radical (O = Cl●-O and O = Cl-O●). We refer to this signal as being from the chloroperoxyl radical (Cl-O-O●). Quantum chemical calculations revealed that the optimal structure of the chloroperoxyl radical is much more thermodynamically stable than that of the chlorine dioxide radical. The UV-visible spectrum of the chloroperoxyl radical showed maximum absorbance at 354 nm. This absorbance had a linear relationship with the chloroperoxyl radical ESR signal intensity. Quantifying the free chlorine concentration by the DPD method also revealed a linear relationship with the maximum absorbance at 354 nm, which in turn showed a linear relationship with the chloroperoxyl radical ESR signal intensity. These linear relationships suggest that the DPD method can quantify chloroperoxyl radicals, which this study considers to be the active species in ASC aqueous solution.

Construction of metronidazole capped in gold nanoparticles against Helicobacter pylori: antimicrobial activity improvement

Introduction:Helicobacter pylori is considered a major agent causing gastritis and peptic ulcer disease. Unfortunately, the occurrence of increasing drug resistance to this bacterium would result in some difficulties in its treatment. Therefore, the application of nanotechnology has been suggested to resolve such problems. Nanoparticles usage in medical research has been expanded in recent years. Among nanometals, gold nanoparticles have exclusive features that can be used in such applications. Using nanotechnology in medical science could help mankind to solve this problem in the future. Aim: Our aim in this research was to investigate the antimicrobial effect of gold nanoparticles on H. pylori strains. Materials and methods: Gold nanoparticles were synthesized by the Turkevich method. Then, their size and dispersion were investigated using spectrophotometry, DLS, and TEM microscopy. Subsequently, the combination of metronidazole and gold nanoparticles was obtained by mixing method, and then the anti-helicobacter effects of the two were evaluated according to CLSI. Results: The highest size of gold nanoparticles was between 12 and 9 nm, and the maximum absorbance was 522 nm; however, in conjugated state, the maximum absorbance was 540 nm, which indicated the accumulation of drug-conjugated nanoparticles in the conjugate state. Some changes indicated the binding of metronidazole to gold nanoparticles. Antimicrobial testing of gold nanoparticles and metronidazole did not affect the Helicobacter pylori. Therefore, the combination of gold nanoparticles and metronidazole had a 17-mm growth inhibition zone. Conclusions: The anti-helicobacter effects of metronidazole significantly increased in conjugation with gold nanoparticles.

A Modified in vitro Clot Lysis Assay Predicts Outcomes in Non-traumatic Intracerebral Hemorrhage Stroke Patients—The IRONHEART Study

Background: Non-traumatic intracerebral hemorrhage (ICH) accounts for 10–15% of all strokes and results in a higher rate of mortality as compared to ischemic strokes. In the IRONHEART study, we aimed to find out whether a modified in vitro clot lysis assay method, that includes the effect of neutrophil extracellular traps (NETs) might predict ICH outcomes.Patients and Methods: In this prospective, observational study, 89 consecutive non-traumatic ICH patients were enrolled. Exclusion criteria included aneurysm rupture, cancer, liver- or kidney failure or hemorrhagic diathesis. On admission, detailed clinical and laboratory investigations were performed. ICH volume was estimated based on CT performed on admission, day 14 and 90. A conventional in vitro clot lysis assay (CLA) and a modified CLA (mCLA) including cell-free-DNA and histones were performed from stored platelet-free plasma taken on admission. Clot formation and lysis in case of both assays were defined using the following variables calculated from the turbidimetric curves: maximum absorbance, time to maximum absorbance, clot lysis times (CLT) and area under the curve (CLA AUC). Long-term ICH outcomes were defined 90 days post-event by the modified Rankin Scale (mRS). All patients or relatives provided written informed consent.Results: Patients with more severe stroke (NIHSS>10) presented significantly shorter clot lysis times of the mCLA in the presence of DNA and histone as compared to patients with milder stroke [10%CLT: NIHSS 0–10: median 31.5 (IQR: 21.0–40.0) min vs. NIHSS>10: 24 (18–31.0) min, p = 0.032]. Shorter clot lysis times of the mCLA showed significant association with non-survival by day 14 and with unfavorable long-term outcomes [mRS 0–1: 36.0 (22.5.0–51.0) min; mRS 2–5: 23.5 (18.0–36.0) min and mRS 6: 22.5 (18.0–30.5) min, p = 0.027]. Estimated ICH volume showed significant negative correlation with mCLA parameters, including 10%CLT (r = −0.3050, p = 0.009). ROC analysis proved good diagnostic performance of mCLA for predicting poor long-term outcomes [AUC: 0.73 (0.57–0.89)]. In a Kaplan-Meier survival analysis, those patients who presented with an mCLA 10%CLT result of >38.5 min on admission showed significantly better survival as compared to those with shorter clot lysis results (p=0.010).Conclusion: Parameters of mCLA correlate with ICH bleeding volume and might be useful to predict ICH outcomes.

Bio-Active Free Direct Optical Sensing of Aflatoxin B1 and Ochratoxin A Using a Manganese Oxide Nano-System

Aflatoxins-B1 (AFB1) and Ochratoxin-A (OchA) are the two types of major mycotoxin produced by Aspergillus flavus, Aspergillus parasiticus fungi, Aspergillus carbonarius, Aspergillus niger, and Penicillium verrocusumv. These toxins are mainly found in metabolite cereals, corn, coffee beans, and other oil-containing food items. Excessive consumption of these toxins can be carcinogenic and lead to cancer. Thus, their rapid testing became essential for food quality control. Herein, manganese oxide nanoparticles (MnO2 nps) have been proposed to explore the interaction with AFB1 and OchA using UV-visible spectroscopy. MnO2 nps were synthesized using the co-precipitation method. They were pure and crystalline with an average crystallite size of 5–6 nm. In the UV-vis study, the maximum absorbance for MnO2 nps was observed around 260 nm. The maximum absorbance for AFB1 and OchA was observed at 365 and 380 nm, respectively, and its intensity enhanced with the addition of MnO2 nps. Sequential changes were observed with varying the concentration of AFB1 and OchA with a fixed concentration of MnO2 nps, resulting in proper interaction. The binding constant (kb) and Gibbs free energy for MnO2 nps-AFB1 and OchA were observed as 1.62 × 104 L g−1 and 2.67 × 104 L g−1, and −24.002 and −25.256 kJ/mol, respectively. The limit of detection for AFB1 and OchA was measured as 4.08 and 10.84 ng/ml, respectively. This bio‐active free direct sensing approach of AFB1 and OchA sensing can be promoted as a potential analytical tool to estimate food quality rapidly and affordable manner at the point of use.

Spectrophotometric Quantification of Iron in Different Pharmaceuticals

Quantification of iron in different pharmaceuticals can be performed by different analytical methods. In this study, a rapid, sensitive and simple spectrophotometric method was used for the determination of iron (II) in different iron tablets. A spectrophotometric method is based on the reaction of iron (II) with 1,10-phenanthroline to form an orange-red chelating complex in an acidic medium. The maximum absorbance of the chelating complex was measured at 510 nm. The Beer Lambert’s law was found to be obeyed in the range of 0.4-4.0 mg/L of iron (II). Out of ten samples analyzed, the observed amount of iron (II) in nine samples were range from 105 to 96 mg whereas in one sample it was observed only 81 mg per 100 mg of the labeled amount of iron(II) by the manufacturer. Thus the results obtained by the spectrophotometric method using 1,10-phenanthroline as a color developing agent were nearly equal to the claimed values of iron (II) in different iron tablets from manufacturing companies.

Assessment of Fenvalerate in Water, Soil and Vegetable Samples

Simple and sensitive spectrophotometric scheme was described for the determination of fenvalerate in environmental samples. The scheme was based on the hydrolysis of 1 N of 5 mL NaOH to form cyanohydrin. The cyanohydrin is reacted with bromine and pyridine to form glutaconic aldehyde, which is then coupled with p-Dimethylaminobenzaldehyde to give yellow dye having maximum absorbance at 440 nm. Beer’s law is obeyed over the concentration range of 0.6- 6.2 µg in a nal solution volume of 25 mL. The molar absorptivity of the colored system is 3.84×104 L mol-1cm-1 and Sandell’s sensitivity is 2.4×10-3 µg cm-2. The reproducibility assessed by carrying out seven days replicate analysis of a solution containing 0.6 µg of fenvalerate in a nal solution volume of 25 mL. The standard deviation and relative standard deviation for the absorbance value were found to be ± 3.4×10-3 and 1.5% respectively. The proposed scheme is sensitive and free from the interference of other toxicants. The analytical parameters were optimized and the scheme was applied to the determination of fenvalerate in environmental samples.