Dermal patch

Using non-natural methionine analog L-azidohomoalanine (L-Aha) and genetically modified E-Coli cells, self-assembling proteins under the conditions needed to create the filament were produced.

Unfortunately, genetic manipulation is challenging due to the high GC (guanine-cytosine) content of the gene which leads to transcription errors.

The second method, chemical modification of the silk proteins should result in the covalent attachment of several copies of a wide range of organic and organometallic ligands using robust or sensitive linkers depending on the application.

Specific site targeting requires the residues to also be modified to be accessible and chemically bioorthogonal to the rest of the silk protein.

Cytosine residues are commonly used for this type of conjugation through a Michael addition, but they tend to undergo exchange reactions which makes them unstable for long durations in a biological environment.

These two methods are rather outdated but have been useful in validating the fact that 4RepCT can be tuned in the important areas of cellular adhesion, antimicrobial potency, and the type of molecule or drug attached to it.

[3] Later azide functional groups were conjugated to the N-terminal of a dragline silk protein using EDC/NHS coupling, yielding glycopolymer-conjugated films with enhanced cell adhesion and DNA-silk chimeras with controllable micro-architectures.

The azide side chains of L-Aha allow highly specific and efficient site-specific conjugation to a lot different of functional molecules via Staudinger ligation with phosphine reagents, and Copper (I)-catalysed azide-alkyne cycloaddition (CuAAC) or Strain promoted azide-alkyne cycloaddition (SPAAC) in click reactions.

It is well known that intracellular Cu(I) is cytotoxic, which means CuAAC is not as common as SPAAC click reactions for research leading to in-vivo applications.

with two different fluorophores and the antibiotic levofloxacin, showcasing the potential of covalently functionalized recombinant spider silk proteins as biomaterials with enhanced properties.

They conducted an inhibition zone assay with the functionalized silk fibers against E. Coli NCTC 12242 bacteria where each factor level contained LB media.

Primarily used for wound binding, the glycoprotein adhesive found on the capture spiral silk, as well as the protein structure of the fiber itself, has mild antibacterial properties.

The silk's viscoelastic properties and high tensile strength and toughness aided wound healing in a way similar to surgical tape.

Despite its superiority to current methods of large-surface-area wound care—gauze wrapping, honey vinegar treatments, and systemic antibiotics—and popular dermal patch uses, spider silk has not found its way into clinical practice.

The most popular proposed use case for dermal applications are: Research shows silkworm silk does not possess any inherent antibiotic characteristics, bio-mimicking mechanical properties, and can cause fatal respiratory allergic reactions in some people.