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Advancement of therapeutic protein therapies can be hindered by their poor stability and short in vivo half‐life. There is emerging evidence that biocompatible zwitterionic materials can prevent nonspecific interactions within proteins systems that contribute to protein instability. Here, zwitterionic hydrogel beads are synthesized from poly(sulfobetaine methyl methacrylate), pSB, using an inverse emulsion, free radical polymerization reaction technique. The transport properties within the zwitterionic hydrogels were characterized using 1H NMR diffusometry. Equilibrium water content as high as 0.90 was measured for the synthesized hydrogels. Our study revealed that the pSB hydrogels are nontoxic, ion responsive, and their swelling is temperature dependent. The zwitterionic hydrogel beads were capable of undergoing lyophilization without aggregation. Hydrogel beads were loaded with a model protein, bovine serum albumin (BSA), using a postfabrication loading technique. The protein loading was studied using confocal laser microscopy, indicating homogenous protein dispersion of up to 40 μg BSA/mg hydrogel within the beads. Furthermore, the release rate of the protein from the synthesized hydrogel was studied at different crosslinker to monomer ratios. The protein encapsulated within the zwitterionic hydrogel had slower rates of thermal aggregation compared to nonencapsulated protein in solution. Furthermore, the protein‐loaded inside the zwitterionic hydrogel better maintained its bioactivity. [ABSTRACT FROM AUTHOR]

Therapeutic proteins are utilized in a variety of clinical applications, but side effects and rapid in vivo clearance still present hurdles. An approach that addresses both drawbacks is protein encapsulation within in a polymeric nanoparticle, which is effective but introduces the additional challenge of destabilizing the nanoparticle shell in clinically relevant locations. This study examined the effects of crosslinking self‐assembled poly(l‐lysine)‐grafted‐poly(ethylene glycol) nanoparticles with redox‐responsive 3,3′‐dithiobis(sulfosuccinimidyl propionate) (DTSSP) to achieve nanoparticle destabilization in a reductive environment. The polymer‐protein nanoparticles (DTSSP NPs) were formed through electrostatic self‐assembly and crosslinked with DTSSP, which contains a glutathione‐reducible disulfide. As glutathione is upregulated in various cancers, DTSSP NPs could display destabilization within cancer cells. A library of DTSSP NPs was formed with varying copolymer to protein (C:P) and crosslinker to protein (X:P) mass ratios and characterized by size and encapsulation efficiency. DTSSP NPs with a 7:1 C:P ratio and 2:1 X:P ratio were further characterized by stability in the presence proteases and reducing agents. DTSSP NPs fully encapsulated the model protein and displayed 81% protein release when incubated with 5 mM dithiothreitol for 12 hr. This study contributes to understanding stimulus‐responsive crosslinking of polymeric nanoparticles and could be foundational to clinical administration of therapeutic proteins. [ABSTRACT FROM AUTHOR]

Introduction: Robot‐assisted therapy for the upper limb (RT‐UL) is an emerging form of intervention for stroke survivors with upper limb deficits. However, there is limited knowledge regarding therapists' perceptions of RT‐UL and the factors influencing the implementation of RT‐UL into the clinical setting. This is important when considering that therapists in Australia are primarily responsible for the prescription of RT‐UL in daily practice. This study aimed to explore occupational therapists' and physiotherapists' perceptions of RT‐UL and the perceived barriers and enablers influencing implementation. Methods: Two discipline‐specific focus groups were conducted involving occupational therapists (n = 6) and physiotherapists (n = 6). Participants were members of the same multidisciplinary team working in an Australian public health rehabilitation facility where RT‐UL (i.e. InMotion2) was being introduced for the first time. Focus groups explored therapist perceptions of the new RT‐UL as well as perceived barriers and enablers to implementation. Focus groups were recorded, transcribed and deductively analysed using the Theoretical Domains Framework (TDF). Results: Out of the 14 domains of the TDF, 7 were raised by participants during the focus groups: environmental context and resources, beliefs about consequences, optimism, knowledge, skills, social influences, and social and professional role and identity. Therapists' expressed their optimism towards the introduction of RT‐UL but believed successful implementation would be primarily dependent on the availability of clinical leadership, training and a suitable client mix. Conclusion: Therapists perceived that RT‐UL would provide opportunity for increased upper limb practice particularly for patients with severe upper limb impairment. To facilitate implementation, support of RT‐UL should come from both management and clinical leaders and training include RT‐UL efficacy, device functionality and patient suitability. The availability of a single RT‐UL device in a workplace may create unique interdisciplinary and logistical challenges. [ABSTRACT FROM AUTHOR]