On the origin of functionalization in one-pot radiation synthesis of nanogels from aqueous polymer solutions

Abstract

Radiation-engineered poly(N-vinyl pyrrolidone) nanogels are very interesting biocompatible nanocarriers for i.v. administration of therapeutics and contrast agents for bioimaging. The manufacturing process is fast and effective, it grants excellent control of particle size and simultaneous sterilization of the formed nanogels. Interestingly, primary amino groups and carboxyl groups, useful for (bio)conjugation, are also formed in a dose-dependent fashion. In this paper, by means of both numerical simulations and experiments, the origin of nanogel size control and functionalization is investigated. This understanding offers a new dimension for the design and production of radiation-sculptured multifunctional nanocarriers from aqueous solutions of polymers

Synthesis of polymer nanogels by electro-Fenton process: investigation of the effect of main operation parameters

“…The tail from that band overlaps with the CH 2 band (at 2,500 cm −1 ) as a result of hydroxyl-to-carbonyl coupling of COOH groups. The presence of carbonyl/carboxylate groups is supported by the absorption at 1,400 cm −1 (signal c in the inset panel) [26]. In addition, EF caused the increase of absorption at 1,661 cm −1 present in the untreated PVP, which is related to carbonyl stretching of the pyrrolidone ring, along with the formation of a couple of new peaks at 1,695 and 1,765 cm −1 (signals b and a, respectively).…”

“…When experiments of increasing duration (900 to 5,400 s) were made, a significant change of R h and M w was observed, thus confirming that the aforementioned oxidative environment in EF allows the formation of a large number of radical centers on dissolved polymer chains. More dilute PVP solutions (< 0.25 wt.%) did not show significant polymer modification when observed in the same time window, probably because the reaction of the hydroxyl radicals with the polymer were outcompeted by their mutual recombination and other wasting reactions [25,26]. The R h showed a very remarkable decrease from 24 nm for the untreated PVP to 16, 12, 9 and 8 nm at 900, 1,800, 3,600 and 5,400 s, respectively, that was accompanied by an initial decrease of M w from 3.95 × 10 5 g mol −1 to 2.5-3.0 × 10 5 g mol −1 for electrolyses up to 1,800 s, followed by a progressive increase of the weight average molecular weight up to 7.8 × 10 5 g mol −1 at 5,400 s. From the comparison among the GPC traces of electrolyzed polymer and that of the virgin PVP (Fig.…”

“…[19,22,23]. Effective crosslinking of poly(vinylpyrrolidone) (PVP) [22][23][24][25][26], PVP copolymers [9,27,28] and other polymers [29] has been reported. As a major inconvenient, high energy radiation processes are not easily implementable into existing production lines, which limits their large-scale applicability.…”

Facile crosslinking of poly(vinylpyrrolidone) by electro-oxidation with IrO2-based anode under potentiostatic conditions

“…This technique is particularly advantageous because of the minimization of toxic additives [1,17], which is crucial for biomedical purposes, along with the easy control of the reaction heat and the concomitant sterilization of the nanogel dispersion [16,17]. Among the various polymers that may undergo crosslinking upon irradiation, poly(Nvinylpyrrolidone) (PVP) has attracted much attention [1,6,11,[18][19][20]. High hydrophilicity and biocompatibility along with adhesive and bonding ability and low toxicity make PVP nanogels appear as suitable candidates for diverse applications [1,21].…”

Nanogel-antimiR-31 conjugates affect colon cancer cells behaviour

“…130 nm and narrow size distribution (PDI < 0.3). [13][14][15][16][17][18] The radiation chemistry of nanogel formation has been recently discussed in ref. 13.…”