A Regenerative Polymer Blend Composed of Glycylglycine Ethyl Ester-Substituted Polyphosphazene and Poly(lactic-co-glycolic acid)

Abstract

In the pursuit of continuous improvement in the area of biomaterial design, blends of mixed-substituent polyphosphazenes and poly(lactic acid−glycolic acid) (PLGA) were prepared, and their morphology of phase distributions for the first time was studied. The degradation mechanism and osteocompatibility of the blends were also evaluated for their use as regenerative materials. Poly-[(ethylphenylalanato) 25 (glycine ethylglycinato) 75 phosphazene] (PNEPAGEG) and poly[(glycine ethylglycinato) 75 (phenylphenoxy) 25 phosphazene] (PNGEGPhPh) were blended with PLGA at various weight ratios to yield different blends, namely

Biomedical applications of polyphosphazenes

“…d, H & E-stained section illustrating the in vivo biocompatibility of the PZ-PLGA. The histological image is also demonstrating the formation of polymer spheres with pore system and collagen tissue infiltration within the pores (Deng, Nair, Nukavarapu, Kumbar, et al, 2010) 2018; Ogueri et al, 2020a;Ogueri et al, 2020b;Zhou et al, 2020).…”

“…It is also worth mentioning that ammonium phosphate from the breakdown of polyphosphazene backbone constitutes a natural buffer due to its amphoteric nature (Allcock, 2016; Allcock & Morozowich, 2012; DeCollibus et al, 2010; Ullah et al, 2017; Wilfert et al, 2014). The self‐neutralizing effect of the polyphosphazenes’ degradation products has become a subject of keen interest in the design of blends composed of polyphosphazenes and clinical polyesters (Ogueri, Ogueri, Allcock, & Laurencin, 2020b). This is crucial to tissue regeneration and drug delivery as the resulting hydrolysis products do not only stabilize the pH of the tissue microenvironment but neutralize the acidic degradation products from the bulk erosion of polyesters in polyphosphazene‐polyester blends (Figure 3b; Z. Huang et al, 2018; Ogueri et al, 2020a; Ogueri et al, 2020b; Zhou et al, 2020).…”

“…The self‐neutralizing effect of the polyphosphazenes’ degradation products has become a subject of keen interest in the design of blends composed of polyphosphazenes and clinical polyesters (Ogueri, Ogueri, Allcock, & Laurencin, 2020b). This is crucial to tissue regeneration and drug delivery as the resulting hydrolysis products do not only stabilize the pH of the tissue microenvironment but neutralize the acidic degradation products from the bulk erosion of polyesters in polyphosphazene‐polyester blends (Figure 3b; Z. Huang et al, 2018; Ogueri et al, 2020a; Ogueri et al, 2020b; Zhou et al, 2020). Besides, the rate at which amino acid ester‐based polyphosphazenes degrade can be influenced by the type of amino acid and the ester function (Allcock, 2016; Khan et al, 2020; Ullah et al, 2017).…”

Thiophene‐based polyphosphazenes with tunable optoelectronic properties

“…2 Polyphosphazenes are of special interest in this regard because they offer a synthetic springboard on which relevant substituent groups can be linked to the polymer chain. [4][5][6] The polyphosphazene backbone confers unique properties that are rare or unusual in thiophene-based backbone polymers. The torsional properties of the P N bond provide high-materials flexibility, which is useful for forming films and fabricating devices.…”

“…The torsional properties of the P N bond provide high-materials flexibility, which is useful for forming films and fabricating devices. 5,[7][8] The optical transparency of polyphosphazene backbone in the visible region of the electromagnetic spectrum ensures that there is no electronic interference between the electroactive side groups and the polymer backbone. Hence, the optoelectronic properties of the polymeric system are manipulated solely by the electronic and chemical structures of the side groups.…”