Novel BUF2-magnetite nanobioconjugates with cell-penetrating abilities

Abstract

IntroductionOne of the major challenges of modern pharmacology is the development of systems for the delivery of therapeutic molecules in a controlled and localized manner. One strategy is to use nanostructured supports, which are well suited to carry a large number of molecules on a per mass basis. A major challenge for these supports is, however, their limited ability to bypass the cell membrane. Recent studies propose that to overcome this issue, potent translocating cell-penetrating peptides (CPPs) can be conjugated to their surfaces.MethodsHere, we conjugated the antimicrobial CPP buforin II (BUF2) to the surface of magnetite nanoparticles to enhance their cell penetration. Conjugates were characterized via Fourier transform infrared spectroscopy, dynamic light scattering, and thermogravimetric analysis, and their biocompatibility was corroborated. The conjugates were delivered in both bacterial and mammalian cells demonstrating the intracellular inclusion in THP-1 cells for the first time.ResultsDespite the promising outcome, our studies showed that the obtained conjugates failed to maintain the native antimicrobial activity of BUF2. We hypothesize that to overcome this issue, a flexible linker can be inserted prior to conjugation.ConclusionOur study highlights the potential of BUF2-magnetite conjugates as cell-penetrating vehicles for the targeted delivery of pharmacological agents. This provides support for the idea of a promising combined drug delivery and antimicrobial peptide therapy.

Tailoring Iron Oxide Nanoparticles for Efficient Cellular Internalization and Endosomal Escape

“…This approach was explored by Song and colleagues through novel PolyMag/DNA/Tat-peptide nanoparticles with endosomal escape abilities and a 4-fold improvement in transfection over the complexes without the peptide [ 253 ]. The same capability has also been shown for ION-PEA-BUF-II nanobioconjugates developed by our group, which were able to efficiently penetrate several mammalian cell lines without significant impact on viability and presented an overall homogeneous cytosolic distribution [ 131 , 254 ]. In addition to agents suitable for protonation, Cristofolini and colleagues developed a novel vehicle that induces the proton-sponge-effect by increasing the luminal concentration of cationic molecules to form an internal hypertonic medium.…”

“…Hybrid ION/UCNP systems have been widely applied in cancer therapy, MRI and diagnosis, gene therapy, and drug delivery [ 308 ]. In general, the most prevalent host matrices for iron oxide core-shell nanoparticles include Y 2 O 3 , Y 2 O 2 S, LaF 3 , BaYF 5 , NaYF 4 , and NaGdF 4 , which have been doped with Yb 3+ /Tm 3+ and Yb 3+ /Er 3+ ions [ 230 , 231 , 232 , 233 , 234 , 235 , 236 , 237 , 238 , 239 , 240 , 241 , 242 , 243 , 244 , 245 , 246 , 247 , 248 , 249 , 250 , 251 , 252 , 253 , 254 , 255 , 256 , 257 , 258 , 259 , 260 , 261 , 262 , 263 , 264 , 265 , 266 , 267 , 268 , 269 , …”

Magnetite Nanoparticles Functionalized with RNases against Intracellular Infection of Pseudomonas aeruginosa

“…Finally, the detachment of the RNases from the magnetite was estimated with a final weight loss step of 5.2% for MNPs-RNase A and close to 8.0% for MNPs-RNase 3/1. These weight losses agree well with those found in our previous works [33,34]. Further evidence of the conjugation efficiencies was provided by a BCA test ( Figure S1), where the weight ratio between the MNPs-RNase bionanoconjugate and the free RNase protein was about 9:2 (2.277 µg per mg of MNP) for the RNase 3/1 and 4:1 (i.e., 2.319 µg per mg of MNP) for RNase A.…”

“…Recently, we prepared bionanoconjugates of MNPs interfaced with antimicrobial and translocating molecules [33,34]. Here, we followed the immobilization protocol that led to superior antibacterial activity for the AMP Buforin II.…”

“…The antibiotic resistance crisis has been attributed to the overuse and misuse of these medications, as well as a lack of new drug development approaches against the emergence of multi-drug resistance (MDR) strains [2]. Over the last decade, studies have focused on the search and evaluation of new high biocompatibility and antimicrobial abilities [33,34,38]. They also have been widely employed to immobilize enzymes, mainly due to the possibility of enhancing their catalytic performance [39], thermal and long term stability [40] and reusability [41][42][43].We recently developed cell-penetrating nanobioconjugates of MNPs by interfacing them with the AMP Buforin II (BUF-II) and the Outer Membrane Protein A (OmpA) of Escherichia coli [33,34].…”