AuCu and AuAg alloys (30 at. % Au) have been immersed in aqueous solutions of chloride and sulphide with additions of protein (mucin). The surfaces of the alloys were subsequently analysed by means of ESCA and compared with previous and similar tests without addition of mucin. No noticeable effect of the mucin addition was observed on the surface composition of the alloys after exposure to the various solutions. Cu in contrast to Ag was found to be selectively dissolved from the 2 or 3 uppermost atomic layers in chloride as well as sulphide solutions (pS greater than 4), both with and without additions of mucin, leaving behind a surface enriched from 10 to 25 at. % in Au. Testing of the same alloys in vivo for 8 d revealed the same tendencies to selective dissolution of Cu. The AuAg alloy was tarnished in the sulphide solutions and in vivo.

Download full-text PDF

Source
http://dx.doi.org/10.1016/0142-9612(85)90099-7DOI Listing

Publication Analysis

Top Keywords

selective dissolution
8
aucu auag
8
auag alloys
8
sulphide solutions
8
alloys
5
dissolution aucu
4
alloys vitro
4
vitro vivo
4
vivo aucu
4
alloys immersed
4

Similar Publications

This study evaluates the efficacy of twin screw melt granulation (TSMG), and hot-melt extrusion (HME) techniques in enhancing the solubility and dissolution of simvastatin (SIM), a poorly water-soluble drug with low bioavailability. Additionally, the study explores the impact of binary polymer blends on the drug's miscibility, solubility, and in vitro release profile. SIM was processed with various polymeric combinations at a 30% / drug load, and a 1:1 ratio of binary polymer blends, including Soluplus (SOP), Kollidon K12 (K12), Kollidon VA64 (KVA), and Kollicoat IR (KIR).

View Article and Find Full Text PDF

Background/objectives: A sustained-release formulation of fenofibrate while enhancing drug dissolution with minimal food effect is critical for maximizing the therapeutic benefits of fenofibrate. Therefore, this study aimed to develop an effective solid dispersion formulation of fenofibrate for simultaneous enhancement in the extent and duration of drug exposure.

Methods: Fenofibrate-loaded solid dispersions (FNSDs) were prepared using poloxamer 407 and Eudragit RSPO at varied ratios via solvent evaporation.

View Article and Find Full Text PDF

Drug-Phospholipid Co-Amorphous Formulations: The Role of Preparation Methods and Phospholipid Selection.

Pharmaceutics

December 2024

Department of Pharmacy, Faculty of Health and Medical Science, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark.

: This study aims to broaden the knowledge on co-amorphous phospholipid systems (CAPSs) by exploring the formation of CAPSs with a broader range of poorly water-soluble drugs, celecoxib (CCX), furosemide (FUR), nilotinib (NIL), and ritonavir (RIT), combined with amphiphilic phospholipids (PLs), including soybean phosphatidylcholine (SPC), hydrogenated phosphatidylcholine (HPC), and mono-acyl phosphatidylcholine (MAPC). : The CAPSs were initially prepared at equimolar drug-to-phospholipid (PL) ratios by mechano-chemical activation-based, melt-based, and solvent-based preparation methods, i.e.

View Article and Find Full Text PDF

This study reports the development of highly conductive and stretchable fibrous membranes based on PVDF/PAN conjugate electrospinning with embedded silver nanoparticles (AgNPs) for wearable sensing applications. The fabrication process integrated conjugate electrospinning of PVDF/PAN, selective dissolution of polyvinylpyrrolidone (PVP) to create porous networks, and uniform AgNP incorporation via adsorption-reduction. Systematic optimization revealed that 10 wt.

View Article and Find Full Text PDF

The aim of this study was to develop and optimize polymeric films based on cellulose derivatives-hydroxypropylmethylcellulose (HPMC), methylcellulose (MC), and sodium carboxymethylcellulose (NaCMC)-as well as pullulan, polyvinyl alcohol (PVA), polyvinylpyrrolidone (PVP), and glycerol (GLY) as plasticizer incorporating extract for potential use in periodontal and gum disease treatment. Over 80 formulations were fabricated using the solvent-casting method, 6 of which were selected for further investigation based on their mechanical properties, mucoadhesion, and disintegration profiles, including three placebo films (OP1 (PVA/PVP/MC400CP/NaCMC/GLY), OP2 (PVA/PVP/MCA15C/NaCMC/GLY), and OP3 (PVA/PVP/HPMC/NaCMC/GLY)) and three films containing extract (OW1, OW2, and OW3). The films demonstrated uniform structural characteristics, with the formulations containing PVA with a high hydrolysis degree (98-99%) and methylcellulose derivatives showing prolonged dissolution times due to physical cross-linking, while the inclusion of NaCMC reduced dissolution time without compromising mucoadhesiveness.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!