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Arg-α,β-dehydrophenylalanine formed self-assembled nanoparticles that could be easily derivatized with folic acid. Folic acid-derivatized nanoparticles showed enhanced cellular uptake and, when loaded with doxorubicin, showed enhanced tumor regression compared with underivatized nanoparticles or native drug, without any adverse side effects, both in vitro and in vivo.

A 99mTc-labelled bis-benzothiazolone-DTPA radio-complex as a SPECT neuroimaging agent.

Synthesis of nanomaterials via 'molecular self-assembly' allows one to define the properties of the nanomaterial by rational design of the individual constituents. Use of peptides for self-assembly offers the ease of design and synthesis, and provides higher biofunctionality and biocompatibility to nanomaterials. Our work focused on the synthesis, characterization and potential biomedical applications of small self-assembled peptide-based nanosystems. We demonstrated that dipeptides containing the conformational restricting residue alpha,beta-dehydrophenylalanine, self-assembled into nanovesicular and nanotubular structures. The nanosystems could encapsulate and release anticancer drugs, showed enhanced stability to proteinase K degradation, a property crucial for them to have a high in vivo half-life, and exhibited no cytotoxicity towards cultured mammalian cells. The dipeptide nanostructures were easily taken up by cells and could evade uptake by reticuloendothelial systems when injected into healthy laboratory animals. Thus, small self-assembling peptides may offer novel scaffolds for the future design of nanostructures with potential applications in the field of drug delivery.

The authors describe a novel multifunctional magneto-fluorescent MFCSNPs-FA-CHI-5FU nanocarrier that consists of magneto-fluorescent nanoparticles (MFCSNPs) targeted with folic acid (FA), modified with chitosan (CHI), and loaded with a 5-flouoruracil (5-FU) in dual mode imaging and targeted drug delivery. Multifunctional magneto-fluorescent nanocarriers show multicolor emission and superparamagnetic behavior which are advantageous for bioimaging and magnetic resonance (MR) imaging, respectively. In-vitro drug release studies show a pH-activated drug release with 92% of loaded 5-FU released in 30 h and MR imaging exhibiting excellent dose-dependent signal enhancement in T 2-weighted images. This suggests that MFCSNPs-FA-CHI-5FU nanocarriers can be used as T 2-weighted negative contrast agents in cancer diagnosis. In-vitro cytotoxicity and anticancer activity of the synthesized MFCSNPs-FA-CHI-5FU nanocarriers were evaluated on three cancer cell lines having different percentages of folate receptors viz. A375, MCF-7, and HeLa cells. The results show a very sensitive drug targeting response. Confocal laser scanning microscopy imaging (CLSM) displays targeted cellular internalization of MFCSNPs-FA-CHI-5FU nanocarriers in cancer cells. The biocompatibility of MFCSNPs-FA-CHI-5FU nanocarriers was ascertained ex-vivo by hemolysis and serum stability studies. The in vivo biodistribution studies were evaluated by radiolabeling MFCSNPs-FA-CHI-5FU nanocarriers with 99m technetium (99mTc). Thus, the synthesized nanocarriers, a dual mode imaging probe, show great potential in targeted drug delivery to improve the existing cancer theranostics.

This kit formulation has the potential for imaging bacterial infections with much higher sensitivity and specificity as compared to other Tc-99m-labeled antibiotics available as convenient ready-to-use kits in routine clinical practice.

aIn the present investigation we have prepared and characterized curcumin (CN)-containing chitosan nanoparticles (CS-NPs) coated with Eudragit FS 30D for colon-specific drug delivery for treatment of ulcerative colitis. Methods: CS-NPs were prepared by ionic gelation using tripolyphosphate. To specify pH sensitive delivery, CS-CN-NPs were coated with Eudragit FS 30D by using a solvent evaporation method. Different process parameters were evaluated, and the optimized formulation was characterized by particle size, size distribution, zeta potential and encapsulation efficiency before lyophilization. The lyophilized product was further subjected to Fourier-transform infrared spectroscopy, and particle morphology and in vitro drug release in different media were studied. Results: the kinetics of in vitro drug release from the CS-CN-NPs revealed sustained release behaviour of the developed carriers. In vivo biodistribution study by gamma-scintigraphy showed good accumulation of the developed nanocarriers in the colonic region. Conclusion: sustained and pH stimulated delivery of CN to the colon was successfully attained via coating of CS-NPs with Eudragit FS 30D to circumvent poor absorption and availability of CN.