Electrospinning is a convenient and promising manufacturing method a variety of materials for tissue engineering. 3D matrices fabricated by electrospinning from solutions of polycaprolactone with human serum albumin or gelatin in 1,1,1,3,3,3-hexafluoroisopropanol were studied. The microstructure of the 3D matrices and surface of the fibers were investigated using scanning electron microscopy. Protein distribution in the surface layer was studied by modification of protein amino groups with N-(2-hydroxyethyl)phenazine and X-ray photoelectron spectroscopy. It was shown, that concentration of the proteins in the surface layer of fibers exceeded their concentration in the initial electrospun solution up to 12 times and the surface layer was enriched in the protein inversely to the concentration of the protein in solution. The minor part of the proteins was released from fibers during first 30-60 min after swelling in water. Treatment of matrices with proteinase K hydrolyzed about 1/3 of the surface exposed human serum albumin. Thus, both methods can be used to study the surface content of the materials produced by electrospinning from blends of synthetic and natural polymers, however X-ray photoelectron spectroscopy appears to be more convenient and informative.
Issledovany matriksy, izgotovlennye metodom élektrospinninga iz rastvorov polikaprolaktona s chelovecheskim al'buminom ili zhelatinom v 1,1,1,3,3,3-geksaftorizopropanole. Mikrostruktura poverkhnosti matriksov byla issledovana s pomoshch'iu skaniruiushcheĭ élektronnoĭ mikroskopii, raspredelenie belka v poverkhnostnom sloe – modifikatsieĭ N-(2-gidroksiétil)fenaziniem i rentgenovskoĭ fotoélektronnoĭ spektroskopieĭ. Pokazano, chto kontsentratsiia belka v poverkhnostnom sloe volokna mozhet do 12 raz prevyshat' takovuiu v iskhodnom rastvore, prichem, chem nizhe kontsentratsiia belka v rastvore, tem vyshe ego otnositel'noe soderzhanie na poverkhnosti volokon. Pri inkubatsii matriksov v vodnykh rastvorakh kontsentratsiia belka v poverkhnostnom sloe umen'shaetsia (ne bolee chem na 10%) v techenie pervykh 30-60 min i sokhraniaetsia na étom urovne dlitel'noe vremia (7 sutok). Obrabotka proteinazoĭ K umen'shaet kontsentratsiiu belka v poverkhnostnom sloe v srednem na tret'. Takim obrazom, oba ispol'zovannykh v rabote metoda mogut byt' primeneny dlia issledovaniia poverkhnostnogo sloia materialov, izgotovlennykh metodom élektrospinninga iz smeseĭ sinteticheskikh i prirodnykh polimerov, odnako rentgenovskaia fotoélektronnaia spektroskopiia predstavliaet soboĭ bolee udobnyĭ i informativnyĭ sposob.
Keywords: 3D-matrices; X-ray photoelectron spectroscopy; chemical modification; electrospinning; synthetic and natural polymers.