Mesh implantation for hernia repair is one of the common surgical techniques. The goal of this review is to highlight the basic requirements of mesh in order to select the most appropriate hernia mesh considering mesh type, physical properties and mechanical properties. Textile warp-knitted synthetic meshes have significantly decreased recurrence rate of hernia. Polypropylene light weight mesh with antimicrobial coating is taking attention of researchers due to its improved compliance, infection resistance, hydrophobicity, inert nature and strong material. Composite meshes have better tissue incorporation, reduced shrinkage and improved mechanical properties. The mesh porosity is an important factor to predict the biocompatibility of all meshes. Usually, large pore size meshes are better than small pore size meshes because of their flexibility, decreased shrinkage, reduced scar bridging and increased tissue ingrowth. All synthetic and composite meshes have higher strength than the human abdominal wall. Mesh type, mesh structure, mechanical properties and mesh implantation techniques are important factors for hernia repair. It is critical to understand the physical structure and mechanical properties of mesh material in relation to human abdominal wall. Moreover, mesh surface functionalization and grafting with plasma is a new development technique to enhance the loading of antimicrobial agent for the prevention of mesh infection.

No abstract

Polypropylene (PP) large pore size nets have been most widely used implants for hernia repair. Nevertheless, the growth of bacteria within PP mesh pores after operation is a major reason of hernia recurrence. Secondly, pre-operative prophylaxis during mesh implantation has failed due to the hydrophobic nature of PP meshes. Herein, chitosan cross-linked and levofloxacin HCl incorporated, antimicrobial PP mesh devices were prepared using citric acid as a bio-based and green cross-linking agent. The inert PP mesh fibers were surface activated using O2 plasma treatment at low pressure. Then, chitosan of different molecular weights (low and medium weight) were cross-linked with O2 plasma activated surfaces using citric acid. Scanning electron microscopy (SEM), energy dispersive X-ray (EDX) spectroscopy, and Fourier transform infrared (FTIR) spectroscopy confirmed that chitosan was cross-linked with O2 plasma-treated PP mesh surfaces and formed a thin layer of chitosan and levofloxacin HCl on the PP mesh surfaces. Moreover, antimicrobial properties of chitosan and levofloxacin HCl-coated PP meshes were investigated using an agar plate release method. The coated PP meshes demonstrated excellent antimicrobial inhibition zone up to 10 mm. Thus, modified PP meshes demonstrated sustained antimicrobial properties for six continuous days against Staphylococcus aureus (SA) and Escherichia coli (EC) bacteria.

Mesh infection is a major complication of hernia surgery after polypropylene (PP) mesh implantation. Modifying the PP mesh with antibacterial drugs is an effective way to reduce the chance of infection, but the hydrophobic characteristic of PP fibers has obstructed the drug adhesion. Therefore, to prepare antimicrobial PP mesh with a stable drug coating layer and to slow the drug release property during the hernia repair process has a great practical meaning. In this work, PP meshes were coated by bio-inspired polydopamine (PDA), which can load and release levofloxacin. PP meshes were activated with cold oxygen plasma and then plasma activated PP fibers were coated with PDA. The PDA coated meshes were further soaked in levofloxacin. The levofloxacin loaded PP meshes demonstrate excellent antimicrobial properties for 6 days and the drug release has lasted for at least 24 h. Moreover, a control PP mesh sample without plasma treatment was also prepared, after coating with PDA and loading levofloxacin. The antimicrobial property was sustained only for two days. The maximum inhibition zone of PDA coated meshes with and without plasma treatment was 12.5 and 9 mm, respectively. On all accounts, the modification strategy can facilely lead to long-term property of infection prevention.

Polypropylene (PP) light weight meshes are commonly used as hernioplasty implants. Nevertheless, the growth of bacteria within textile knitted mesh intersections can occur after surgical mesh implantation, causing infections. Thus, bacterial reproduction has to be stopped in the very early stage of mesh implantation. Herein, novel antimicrobial PP meshes grafted with β-CD and complexes with triclosan were prepared for mesh infection prevention. Initially, PP mesh surfaces were functionalized with suitable cold oxygen plasma. Then, hexamethylene diisocyanate (HDI) was successfully grafted on the plasma-activated PP surfaces. Afterwards, β-CD was connected with the already HDI reacted PP meshes and triclosan, serving as a model antimicrobial agent, was loaded into the cyclodextrin (CD) cavity for desired antibacterial functions. The hydrophobic interior and hydrophilic exterior of β-CD are well suited to form complexes with hydrophobic host guest molecules. Thus, the prepared PP mesh samples, CD-TCL-2 and CD-TCL-6 demonstrated excellent antibacterial properties against Staphylococcus aureus and Escherichia coli that were sustained up to 11 and 13 days, respectively. The surfaces of chemically modified PP meshes showed dramatically reduced water contact angles. Moreover, X-ray diffractometer (XRD), differential scanning calorimeter (DSC), and Thermogravimetric (TGA) evidenced that there was no significant effect of grafted hexamethylene diisocyanate (HDI) and CD on the structural and thermal properties of the PP meshes.

No abstract

No abstract

The authors describe colorimetric test strips by using electrospun nanofiber membranes (NFMs) carrying gold/silver core/shell nanoparticles (Au/Ag NPs). The Au/Ag NPs were immobilized on aminated porous polyacrylonitrile NFMs to obtain test strips with a tortuous porous structure and a large surface area (38.6 m g). The color of the resultant NFMs, measured at a wavelength of 420 nm, is red-shifted when exposed to copper ions (Cu) with a color change from yellow to pink to colorless. The effect is due to leaching Au/Ag NPs from the NFMs in the presence of ammonium chloride, thiosulfate and Cu upon which soluble thiosulfate complexes of Ag, Au and Cu are formed. The effect can be readily seen with bare eyes. Under optimized conditions, this method has a low limit of detection (50 nM at S/N = 3), a fast assay time (3 min), good specificity, and excellent reversibility. The colorimetric test strip was successfully applied to the analysis of Cu in drinking water sample. Graphical abstract Schematic of the preparation of test strips for Cu by immobilizing Au/Ag core-shell nanoparticles on aminated polyacrylonitrile nanofibers.