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This work aimed at developing a methodology for examining the naturally grown passive layer of a thickness of just a few nanometers of an austenitic CrMnN steel by means of atom probe tomography and gaining knowledge on the structure of this alloy’s passive layer. The sample surface was ground, polished, cleaned, degreased, electrolytically polished, and oxidized in air to produce a reproducible passive layer. The oxide layer was subsequently coated with a silver layer of a thickness of 3 μm. The silver layer protects the oxide layer during the preparation of the atom probe tips in the focused ion beam microscope and the alignment of the tip in the atom probe. The samples were measured in the atom probe’s pulsed-voltage mode. The findings show that an enrichment of oxygen, molybdenum, nitrogen, and chromium and a depletion of manganese, nickel, and iron occur in the area of the passive layer.

For plastic mold steels, secondary hardening as well as hardenable, corrosion-resistant steels are used. Secondary hardening can be achieved through alloying with Ni, Ti, Al and Cu. The precipitation sequence of combined Cu and intermetallic NiAl particles depends on the precise ratio of the alloying contents. In this study, a dual hardening iron-based alloy with a high ratio of Ni/Cu and Al/Cu and low Carbon content is investigated. These dual hardening steels represent alloys that utilize both carbidic and intermetallic secondary hardening precipitates to achieve secondary hardening. The investigations focus on the initial precipitation of intermetallic particles in order to analyze the sequence of precipitate formation for a specific ratio of alloying elements. DSC measurements were used to identify characteristic precipitation temperatures between 360 °C and 600 °C and the corresponding heat treatment conditions were reproduced using a quenching dilatometer. The initial stages of precipitate formation were examined using high-resolution atom probe tomography. C-enrichments in the form of retained austenite films were evident in the examined material. Heterogeneous nucleation of Cu-NiAl precipitates on these retained austenite films was attributed to exothermal reactions at 460 °C.

The primary purpose of the present research was to design a novel lipid-polymer hybrid nanoparticulate system of lonidamine based on the DoE approach for the effective treatment of benign prostatic hyperplasia. Hybrid nanoformulations were prepared through one-step self-assembly approach. The primary core material used PLGA, while DSPE-PEG-COOH and l-α-phosphatidylcholine were employed as lipid-PEG shell layer and lipid monolayer at the interface of the lipid-PEG shell and polymeric core, respectively. The molar ratios of PEG conjugated lipid to polymer and total lipids to l-α-phosphatidylcholine were determined as the investigated independent variables. Nine hybrid formulations were optimized by the application of a 32factorial design to evaluate the major changes on the characteristics of hybrid systems such as entrapment efficiency, mean particle size and surface charge. Shape and morphology characteristics, in vitro release profiles, thermal behavior and interactions, lipid shell thickness, and storage stability were also evaluated. The important outcomes of this research revealed that the hybrid formulations prepared at the center point of the design exhibited an excellent core-shell structure, high entrapment efficiency values, and desired particle sizes. The linearity graphics and the surface response plots demonstrated significant effectiveness between the independent variables and the experimental responses.

Background: Semisolid SLNs are novel strategy for dermal drug administration instead of incorporating the SLN dispersions into conventional semisolids. Etofenamate loaded semisolid SLNs were successfully prepared and in vitro characterization of formulations were performed in our previous study. The present study is an attempt to evaluate the dermal behavior of the semisolid SLNs selected on the basis of previous research and investigate the properties in terms of the convenience for topical applications. Objective: The objective of this study is to evaluate the skin penetration characteristics of semisolid SLN formulations. The occlusive and mechanical properties of semisolid SLNs were also evaluated because of their impression on the dermal behavior of the formulations. Method: The occlusive properties were investigated by in vitro occlusion test. Texture analysis was performed to define the hardness, compressibility, adhesiveness, cohesiveness and elasticity of the formulations. Rat skin was chosen to evaluate the ex vivo penetration of etofenamate loaded semisolid SLNs and commercial gel product. Coumarin-6 was used to visualize the dermal distribution of the semisolid SLN formulations. For monitorizing the penetration of coumarin-6 into the skin samples Confocal Laser Scanning Microscopy was employed. Results: The occlusive and mechanical properties of C1 coded semisolid SLN formulation were found more favorable in comparison with P1. The cumulative etofenamate amount in skin samples was found to be 39.88 ± 1.50 μg/cm2 for C1 and 30.56 ± 2.10 μg/cm2 for P1 coded formulations. According to CLSM images, greater fluorescence intensities and deeper skin penetrations were obtained with both of the semisolid SLNs in comparison to plain Carbopol gel. Conclusion: It can be concluded that the semisolid SLNs are promising alternative dermal drug delivery systems to the conventional dosage forms.

Etofenamate (2-(2-hydroxyethoxy) ethyl 2-[[3-(trifluoromethyl)phenyl]amino]benzoate) (ETO) is a yellowish viscous liquid which is a nonsteroidal anti-inflammatory drug (NSAID) that has been applied topically for joint and muscular pain and soft tissue disorders. Solid lipid nanoparticles (SLNs) are colloidal drug delivery systems prepared by non-irritant and nontoxic lipids that attract great interest because of their unique features. Semisolid SLNs are novel approach for dermal application of SLNs. The aim of this study was to show the development, validation, and application of a simple, selective and reliable RP-LC method that was extensively validated for its specificity and stability-indicating properties from its forced hydrolytic, oxidative, photolytic and thermal degradation products. In addition, the proposed method presented to application of ETO from rat skin extract in according to the United States Pharmacopeia and International Council on Harmonization Guidelines. For this reason, XSelect HSS T3 XP (150 x 4.6 mm ID x 2.5μm) (Waters Corp. Milford, MA, USA) analytical column was chosen for the best resolution. Mobile phase consisted of 0.1 % H3PO4 in bidistilled water (pH adjusted to 7.0 with 5M NaOH) and acetonitrile in the ratio of (40:60, v/v) with the flow rate of 1 mL.min-1. The volume of the sample solutions was injected at 10μL and the detector was set up at 285 nm. The analysis was carried out at a temperature of 45°C. The developed stability indicating method presented low limit of detection, low limit of quantitation and good resolution between any of interferences from both commercial formulation and developed SLN formulation from rat skin, with symmetric, pure and perfect peak homogeneity. High percentage of recovery results shows that the proposed method is free from the interferences of the commonly used excipients and additives in the formulations of the commercial product or semisolid SLN formulations and also biological derivatives.

The powder metallurgically processed carbon-free alloy Fe-25Co-15Mo (in m.-%) can be hardened via the precipitation of an intermetallic µ phase (Fe, Co)7Mo6by solution annealing, quenching and subsequent aging. Solution annealing is carried out in the austenite region which leads to a supersaturation of the matrix with molybdenum and the precipitation of nm sized µ phase particles during subsequent aging. “Primary” µ phase particles that are 1–2 µm in diameter formed during prior hot isostatic pressing are the source of molybdenum for aging. However, during solution annealing, these “primary” µ phase particles also impede grain growth. Therefore, the solution annealing process should be optimized to avoid extensive grain growth while still obtaining sufficient molybdenum contents in the matrix. In order to characterize the solution annealing process as a function of time and temperature, dilatometer experiments were performed to monitor the dissolution kinetics of the µ phase. The remaining µ phase fraction was determined in a complementary way by applying two characterization methods: Quantitative analysis of scanning electron microscope images and X-ray diffraction.

Zofenopril calcium (one-half calcium salt) is a prodrug ester analog of captopril whose biological effects are manifested by its active component, SQ 26,333. Because of the relative insolubilities of both zofenopril calcium and SQ 26,333, zofenopril potassium salt and SQ 26,703, the arginine salt of the active ACE (angiotensin I converting enzyme) inhibitory moiety of zofenopril, were employed in many of the following studies. The in vitro and in vivo pharmacological effects of zofenopril have been evaluated and comparisons have been made to captopril. In vitro, SQ 26,703 was more potent than captopril as an inhibitor of rabbit lung ACE (IC508 vs. 23 nM). SQ 26,703 was also a potent inhibitor of angiotensin I (AI)-induced contractions (EC503 nM) and a potentiator of bradykinin-induced contractions (EC501 nM) of isolated guinea pig ileum, while it had no effect on the inotropic effects of angiotensin II, BaCl2, PGE1, histamine, serotonin, or acetycholine in the same tissue, signifying that zofenopril is a specific inhibitor of ACE. In vivo, the potency of SQ 26,703 was equal to or greater than that of captopril as an inhibitor of an AI pressor response when given intravenously to rats, dogs, and monkeys. After oral administration of equimolar doses, zofenopril was the more effective and longer lasting ACE inhibitor in all three species. In SHR, doses of 6.6 and 22.0 mg/kg, p.o. lowered pressure by 20 and 33 mm Hg, respectively, while 30 mg/kg of captopril lowered pressure by 25 mm Hg. Zofenopril's effects were longer lasting. A combination of zofenopril and hydrochlorothiazide lowered pressure more (34 mm Hg) than zofenopril alone (20 mm Hg) in SHR. In two-kidney, one-clip renal hypertensive rats, zofenopril was more effective than captopril as an antihypertensive and again zofenopril's effects lasted longer. In anesthetized dogs, zofenopril had no effect on catecholamine-induced pressor responses or reflex changes in blood pressure and heart rate during head-up tilting or bilateral carotid artery occlusion. It is concluded that zofenopril is an effective and long lasting inhibitor of ACE in rats, dogs, and monkeys and an effective antihypertensive agent in rats.

Reaction of 5,5-dimethyl-3-pyrazolidinone (1) with 2-indanone (2) gave 5,5-dimethyl-2-(1H-indenyl-2)-3-pyrazolidinone (3) instead of the expected azomethine imine 4. Although reaction of 2-substituted 3-pyrazolidinones with acetylenedicarboxylates usually gives ring expansion products, such as 1,2-diazepines, treatment of 3 with dialkyl acetylenedicarboxylates (5, R = Me; 6 R = Et) resulted in the formation of rel-(7aR,12aS)-6,7-bis(alkoxycarbonyl)-3,4-dihydro-4,4-dimethyl-7aH-indano[1,2-b]pyrrolo[1,2-a]pyrimidin-2-ones (7, R = Me; 9, R = Et) as major products and 3,4-bis(alkoxycarbonyl)-7,7-dimethyl-2-(indenyl-2)-6,7-dihydro-2H,6H-1,2-diazepin-5-ones (8, R = Me:  10, R = Et) as minor products.

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Tetrahydroaminonaphthols such as (I) ‐ (III) are synthesized and biologically tested.