The main functions of biological adhesives and sealants are to repair injured tissues, reinforce surgical wounds, or even replace common suturing techniques. In general surgery, adhesives must match several requirements taking into account clinical needs, biological effects, and material features; these requirements can be fulfilled by specific polymers. Natural or synthetic polymeric materials can be employed to generate three-dimensional networks that physically or chemically bind to the target tissues and act as hemostats, sealants, or adhesives. Among them, fibrin, gelatin, dextran, chitosan, cyanoacrylates, polyethylene glycol, and polyurethanes are the most important components of these interfaces; various aspects regarding their adhesion mechanisms, mechanical performance, and resistance to body fluids should be taken into account to choose the most suitable formulation for the target application. This review aims to describe the main adhesives and sealant materials for general surgery applications developed in the past decades and to highlight the most important aspects for the development of future formulations.

N-linked or O-linked glycans derived from glycoprotein processing carry, an N-acetylglucosamine or an N-acetylgalactosamine respectively, at their reducing termini. The presence of the N-acetylamino group on C-2 of reducing sugar residues has been reported to hamper the derivatization reaction with a chromophore at the anomeric centre. In this paper N-acetyllactosamine, N-acetylglucosamine, N-acetylgalactosamine and several other neutral monosaccharides are coupled to three different dyes (4-aminobenzonitrile, 2-aminopyridine, 2-aminobenzoic acid (2-AA)) by reductive amination and analysed by CE with UV detection. The 2-AA derivatives showed the lowest concentration detection limits, varying approximately in the 2-3 muM range for the saccharides tested including the N-acetamido ones. The possibility to separate and detect with the same sensitivity ten 2-AA-labelled monosaccharides mainly found in mammalian or plant glycoproteins in a single CE run is highlighted. The analysis has been carried out in less than 25 min using the borate-complexation method in CZE mode. The influence of the strength of the acid used as catalyst in the chemical modification of the sugars with 2-AA is also shortly addressed.

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Capillary electrophoresis (CE) applications to charged polysaccharides are briefly reported. A simple procedure is presented to determine the esterification degree of a hyaluronan derivative. In this case, the degree of substitution was as low as 14%. The molecular weight distribution of mannuronic oligosaccharides mixture produced by hydrolysis of native polymannuronic is readily calculated from peak area of the species resolved by CE on the basis of a specific degree of polymerization. The influence of the applied electric field strength on the free solution mobility of hyaluronan samples is briefly addressed for molar masses of the order of 10(5) and 10(6) g/mol. The data are compared with the results obtained for a 50% galactose-substituted hyaluronic acid (HA). Mobility data obtained as a function of buffer pH for a native HA sample as well as for two galactose-amide HA derivatives, having slightly different degrees of substitution, are presented and discussed in terms of the polymer charge density parameters xi. In most cases, more questions than answers arise from the application of CE to charged polysaccharides. However, perspectives are disclosed for a further understanding of the reliability of CE applied for the structural elucidation of such macromolecules.

CE applications to charged polysaccharides are briefly reported. A simple procedure is presented to determine the esterification degree of a hyaluronan derivative. In this case the degree of substitution was as low as 14 %.The molecular weight distribution of mannuronic oligosaccharides mixture produced by hydrolysis of native polymannuronic is readily calculated from peak area of the species resolved by CE on the basis of a specific degree of polymerization.The influence of the applied electric field strength on the free solution mobility of hyaluronan samples is briefly addressed for molar masses of the order of 10(5) and 10(6) g/mol. The data are compared with the results obtained for a 50 % galactose substituted HA.Mobility data obtained as a function of buffer pH for a native HA sample as well as for two galactose-amide HA derivatives, having slightly different degrees of substitution, are presented and discussed in terms of the polymer charge density parameters ξ.In most cases, more questions than answers arise from the application of CE to charged polysaccharides. However, perspectives are disclosed for a further understanding of the reliability of CE applied for the structural elucidation of such macromolecules.