Honey was used to treat wounds since ancient times till nowadays. The present study aimed at preparing a honey-based hydrogel and assay its antimicrobial properties and wound healing activity; in-vitro and in-vivo. Topical honey hydrogel formulations were prepared using three honey concentrations with gelling agents; chitosan and carbopol 934. The prepared formulae were evaluated for pH, spreadability, swelling index, in-vitro release and antimicrobial activity. The pH and spreadability were in the range of 4.3–6.8 and 5.7–8.6 cm, respectively. Chitosan-based hydrogel showed higher in-vitro honey release with diffusional exponent ‘n ≤ 0.5 indicates Fickian diffusion mechanism. Hydrogel formulae were assessed for in-vitro antimicrobial activity using Disc Diffusion antibiotic sensitivity test against common burn infections bacteria; Pseudomonas aeruginosa, Staphylococcus aureus, Klebsiella pneumonia and Streptococcus pyogenes. The 75% honey-chitosan hydrogel showed highest antimicrobial activity. This formula was tested for in-vivo burn healing using burn-induced wounds in mice. The formula was evaluated for burn healing and antibacterial activities compared to commercial product. 75% honey-chitosan hydrogel was found to possess highest healing rate of burns. The present study concludes that 75% honey-chitosan hydrogel possesses greater wound healing activity compared to commercial preparation and could be safely used as an effective natural topical wound healing treatment.

Thermoresponsive gels containing gold nanoparticles (AuNPs) were prepared using Pluronic®127 alone (F1) and with hydroxypropyl methylcellulose (F2) at ratios of 15% w/w and 15:1% w/w, respectively. AuNPs were evaluated for particle size, zeta-potential, polydispersity index (PDI), morphology and XRD pattern. AuNP-containing thermoresponsive gels were investigated for their gelation temperature, gel strength, bio-adhesive force, viscosity, drug content, in vitro release and ex-vivo permeation, in addition to in vitro antibacterial activity against bacteria found in burn infections, Staphylococcus aureus. In vivo burn healing and antibacterial activities were also investigated and compared with those of a commercial product using burn-induced infected wounds in mice. Spherical AuNPs sized 28.9–37.65 nm displayed a surface plasmon resonance band at 522 nm, a PDI of 0.461, and a zeta potential of 34.8 mV with a negative surface charge. F1 and F2 showed gelation temperatures of 37.2 °C and 32.3 °C, bio-adhesive forces of 2.45 ± 0.52 and 4.76 ± 0.84 dyne/cm2, viscosities of 10,165 ± 1.54 and 14,213 ± 2.31 cP, and gel strengths between 7.4 and 10.3 sec, respectively. The in vitro release values of F1 and F2 were 100% and 98.03% after 6 h, with permeation flux values of (J1) 0.2974 ± 2.85 and (J2) 0.2649 ± 1.43 (µg/cm2·h), respectively. The formulations showed antibacterial activity with the highest values for wound healing properties, as shown in vivo and by histopathological studies. This study demonstrates that a smart AuNPs thermoresponsive gel was successful as an antibacterial and wound healing transdermal drug delivery system.

Mass spectrometric epitope mapping has become a versatile method to precisely determine a soluble antigen's partial structure that directly interacts with an antibody in solution. Typical lengths of investigated antigens have increased up to several 100 amino acids while experimentally determined epitope peptides have decreased in length to on average 10-15 amino acids. Since the early 1990s more and more sophisticated methods have been developed and have forwarded a bouquet of suitable approaches for epitope mapping with immobilized, temporarily immobilized, and free-floating antibodies. While up to now monoclonal antibodies have been mostly used in epitope mapping experiments, the applicability of polyclonal antibodies has been proven. The antibody's resistance towards enzymatic proteolysis has been of key importance for the two mostly applied methods: epitope excision and epitope extraction. Sample consumption has dropped to low pmol amounts on both, the antigen and the antibody. While adequate in-solution sample handling has been most important for successful epitope mapping, mass spectrometric analysis has been found the most suitable read-out method from early on. The rapidity by which mass spectrometric epitope mapping nowadays is executed outperforms all alternative methods. Thus, it can be asserted that mass spectrometric epitope mapping has reached a state of maturity, which allows it to be used in any mass spectrometry laboratory. After 25 years of constant and steady improvements, its application to clinical samples, for example, for patient characterization and stratification, is anticipated in the near future. © 2016 Wiley Periodicals, Inc. Mass Spec Rev 37:229-241, 2018.

Molecular & Cellular Proteomics 18.8 1543 * We acknowledge the German Academic Exchange Service (DAAD) for providing scholarships for BD (No. 91566064). The WATERS Synapt G2S mass spectrometer has been bought through an EU grant [EFRE-UHROM 9] made available to MOG.

The protein termed RA33 was determined to be one major autoantigen in rheumatoid arthritis (RA) patients and antiRA33 auto-antibodies were found to appear shortly after onset of RA. They are often detectable before a final diagnosis can be made in the clinic. The aim of our study is to characterise the epitope of a monoclonal antiRA33 antibody on recombinant RA33 using mass spectrometric epitope mapping. Recombinant RA33 has been subjected to BrCN cleavage and fragments were separated by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE). Subsequent in-gel proteolytic digestion and mass spectrometric analysis determined the partial sequences in the protein bands. Western blotting of SDS-PAGE-separated protein fragments revealed immuno-positive, i.e. epitope-containing bands. BrCN-derived RA33 fragments were also separated by high- performance liquid chromatography (HPLC) and immuno-reactivity of peptides was measured by dot-blot analysis with the individual HPLC fractions after partial amino acid sequences were determined. The epitope region identified herewith was compared to data from peptide chip analysis with 15-meric synthetic peptides attached to a glass surface. Results from all three analyses consistently showed that the epitope of the monoclonal antiRA33 antibody is located in the aa79-84 region on recombinant RA33; the epitope sequence is MAARPHSIDGRVVEP. Sequence comparisons of the 15 best scoring peptides from the peptide chip analysis revealed that the epitope can be separated into two adjacent binding parts. The N-terminal binding parts comprise the amino acid residues "DGR", resembling the general physico-chemical properties "acidic/polar-small-basic". The C-terminal binding parts contain the amino acid residues "VVE", with the motif "hydrophobic-gap-acidic". The matching epitope region that emerged from our analysis on both the full-length protein and the 15-meric surface bound peptides suggests that peptide chips are indeed suitable tools for screening patterns of autoantibodies in patients suffering from autoimmune diseases.