Extended release formulations using silk proteins for controlled delivery of therapeutics

Abstract

Introduction-Silk is a promising biomaterial for controlled delivery of therapeutic molecules. Silk has a unique protein chemistry and structure that can be tuned to form different carrier formats. The protein has been studied for injectable or implantable sustained release depot systems for the targeted or localized delivery of drugs.Areas covered-An overview of natural silk proteins for controlled delivery of therapeutics is provided, with a focus on the features of silk proteins that allow them to be useful tools for controlled delivery. Recent applications of natural silk proteins as controlled delivery systems are also summarized.Expert opinion-The versatility of silk proteins makes them desirable biomaterials for a broad range of applications for controlled delivery of both small and large molecules. Further, the degradation profile leading to peptides and amino acids provides compatibility with pH-sensitive therapeutics like complex proteins in formulation and delivery. While silk sericin and spider silks are under study, silk fibroin extracted from silkworms (e.g., Bombyx mori) dominates pharmaceutical studies with silk. Silk fibroin can be formed into drug delivery tools for systemic or local injections, topical and transdermal applications, and implantation; depending on the target disease and therapeutic molecule. In vitro to in vivo correlations and scale-up needs are the next steps towards clinical applications.

Sericin based nanoformulations: a comprehensive review on molecular mechanisms of interaction with organisms to biological applications

“…This protein biopolymer has been used as inert or non-inert supports to fabricate films, sponges, fibers, patches, scaffolds, hydrogels, micro, and nanostructures [ 75 , 76 ]. Among these materials, nanostructures have been highlighted considering their antibacterial effects, wound healing, artificial skin, articular cartilage, scaffolds for tissue regeneration, and small molecules delivery systems [ 77 ]. Table 1 summarizes the nanoformulations based on SER and their applications.…”

“…Considering the easy functionalization of SER molecule, strategies for producing more specific and environmental-sensitive systems are used especially for tumor targeting. Several production techniques have been described to prepare these types of nanoparticles [ 75 , 77 ], and beyond that, some nanocarriers have smart release capacity, which means that they can release drugs in specific conditions, for example when changing the pH values [ 7 , 40 , 83 , 84 , 88 ]. In particular, Jahanshahi et al [ 89 ], developed a sericin anchored fluorinated graphene oxide (FGO) pH-responsive carrier for a controlled release of curcumin (Fig.…”

The Use of Micro- and Nanocarriers for Resveratrol Delivery into and across the Skin in Different Skin Diseases—A Literature Review

“…Silk proteins are also an interesting biomaterial whose potential is currently being explored for use in controlled drug delivery. Previously, silk proteins, in the form of hydrogels or creams, have been used with positive results in the treatment of burn wounds in regenerative medicine, in scar reduction, and the prevention of infections [ 156 , 157 , 158 , 159 , 160 ]. The lack of disease progression after 4 weeks of treatment was confirmed by the concentration of pro-inflammatory interleukins (IL-1β and TGF-1β) as well as by the following anatomopathological measurements: low level of vessel formation and smaller collagen compaction in the samples tissue gum samples.…”

Silk Particles as Carriers of Therapeutic Molecules for Cancer Treatment

“…Although silk is protein-based material, it is characterized by the exceptional mechanical properties, compatibility with standard sterilization techniques (including high-temperature treatment), and simplicity of preparation methods [22][23][24][25]. Silk can be tailored for size, stability, drug loading/release kinetics by simply changing the process of the particle formation and post-treatment of the material [26]. Moreover, the active-targeting delivery may be achieved upon blending or conjugation of various targeting ligands such as peptides, antibodies, aptamers, etc.…”