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Based on the self-assembly properties of vapreotide acetate (Vap), one kind of novel vapreotide acetate‑gold nanoflowers (Vap-AuNFs) was fabricated for the first time by biomimetic mineralization method using Vap as a template. The Vap-AuNFs possessed anisotropic structure with a large absorption cross-section, which were face-centered cubic crystalline, exhibiting a remarkable monodisperse, narrow size (154 nm) distribution and good stability in aqueous solution. The apparent anisotropy of the gold nanostructure with high molar extinction coefficient can cause significantly higher plasmon absorption of Vap-AuNFs in the near infrared (NIR) region compared with Au nanoparticles (AuNPs), so the nanocomplex can induce remarkably enhanced photothermal conversion efficiency under NIR light irradiation. Breathtakingly, Vap-AuNFs exhibited superior biocompatibilities compared to AuNPs, as well as enhanced Hela cells lethality under NIR irradiation. This novel method was simple, low cost and green for the design and preparation of anisotropic gold nanoflowers with outstanding NIR laser-induced local hyperthermia, highlighting their potential applications in biomedical fields.

Vapreotide acetate (Vap) was used as a biotemplate to synthesize silver nanocages through direct co-incubation of a AgNO 3 solution, following by reduction using fresh NaBH 4 . The characterized vapreotide-templated silver nanocages (Vap-AgNCs) presented a wide and red shifted absorption band with a maximum between 480 nm and 800 nm and possessed a uniform structure with a face-centered cubic crystal structure. The biocompatibility of Vap-AgNCs was assessed using the MTT method, indicating Vap-AgNCs had better biocompatibility when its concentration was lower than 2.5 × 10 − 4 mmol·L − 1 . The photothermal characteristics of Vap-AgNCs were analyzed with laser irradiation (808 nm, 1.5 W·cm − 2 ) and the results showed that the temperature of the Vap-AgNCs solution reached 45 °C starting from 25 °C within 5 min. Additionally, Vap-AgNCs with a laser led to HeLa cell death. Therefore, the prepared Vap-AgNCs is expected to be an effective photothermal therapy agent.

Palladium nanomaterials have attracted great attention on the development of electrocatalysts for fuel cells. Herein, we depicted a novel strategy in the synthesis of palladium nanoparticles with superior electrocatalytic activity. The new approach, based on the self-assembly of bacitracin biotemplate and palladium salt for the preparation of bacitracin-palladium nanoparticles (Bac-PdNPs), was simple, low-cost, and green. The complex, composed by a series of spherical Bac-PdNPs with a diameter of 70 nm, exhibited a chain-liked morphology in TEM and a face-centered cubic crystal structure in X-Ray diffraction and selected area electron diffraction. The palladium nanoparticles were mono-dispersed and stable in aqueous solution as shown in TEM and zeta potential. Most importantly, compared to the commercial palladium on carbon (Pd/C) catalyst (8.02 m 2 g −1 ), the Bac-PdNPs showed a larger electrochemically active surface area (47.57 m 2 g −1 ), which endowed the products an excellent electrocatalytic activity for ethanol oxidation in alkaline medium. The strategy in synthesis of Bac-PdNPs via biotemplate approach might light up new ideas in anode catalysts for direct ethanol fuel cells.

Gold nanostructures, particularly gold nanocages or nanoshells (AuNCs or AuNSs), exhibit remarkable optical properties due to their excellent surface plasmon resonance, allowing their potential use in biomedical fields. Herein, we report the controlled synthesis of AuNCs and AuNSs simply using lanreotide acetate (Lan) as a biotemplate. Gold nanomaterials were obtained via co-incubation between a HAuCl4 solution and Lan peptide and controlling the reduction reaction process. AuNCs and AuNSs prepared in this method were about 120 nm and 150 nm in diameter, respectively, which have the desired passive targeting to tumor. Surprisingly, both AuNCs and AuNSs showed superior photothermal inhibitory effects for cancer cells with only 0.8 W cm−2 laser power in the in vivo and vitro experiments; moreover, the AuNCs showed better antitumor activity and photothermal conversion efficiency than the AuNSs. In this study, two kinds of gold nanostructures were fabricated using the same template molecule, and AuNCs showed higher photothermal conversion efficiency due to their anisotropic structure.

In recent years, there has been increasing interest in fabricating noble metal nanoparticles using bio-templates for various biomedical applications, with the hope of finding a low cost method for their construction by a fairly simple and environmentally friendly synthetic strategy. In this study, novel self-assembled superstructures, namely, bacitracin–platinum nanoparticles (Bac–PtNPs), were designed and prepared under mild conditions. Bacitracin has two purposes: self-assembly to form a specific structure and the recognition of platinum nanoparticles, providing nucleation sites to form the nanomaterials. The spherical chain-like Bac–PtNPs were synthesized by the incubation of bacitracin and PtCl4 aqueous solutions at pH 2.0 for 24 h. The nanoparticles were face-centered cubic (fcc) crystalline, which were stable in aqueous solution. Functional groups such as –NH and –OH on the bacitracin surface serve as binding moieties and mediated the initial growth of the Pt nanoparticles. Anti-tumor effects exhibiting excellent therapeutic efficacy were confirmed both in vitro and in vivo. This study introduces a simple and effective platform for the design and preparation of the antitumor nanocomplexes, highlighting their potential applications in the biomedical field.

A new type of vapreotide-templated Ag/Au bimetallic nanoshells (Vap@Ag/AuNSs) were successfully designed and fabricated based on polypeptide-directed mineralization and hierarchical self-assembly mechanisms under mild synthetic conditions. The nanoparticles with polypeptides serving as a core and coated Ag/Au bimetallic nanoshells exhibit diverse advantages, such as excellent biocompatibility, tumor targeting and low-cost. The Vap@Ag/AuNSs share excellent dispersibility, uniform size (120 nm) and a positive zeta potential (36.74 ± 4.49 mV), hence they easily accumulate in negatively charged tumor tissue. The results of thermal imaging, temperature variation assays and photothermal conversion efficiency (41.6%) indicated that Vap@Ag/AuNSs have excellent photothermal conversion capability. Based on their photothermal response, as well as biocompatibility determined by MTT assay, the prominent anti-tumor effects of Vap@Ag/AuNSs have been verified by fluorescein diacetate staining. Therefore, Vap@Ag/AuNSs are novel and promising candidates for photothermal tumor therapy.

In this study, the self-assembly of platinum nanoshells (PtNSs) in facile conditions, using the adenovirus shuttle vector-GFP (Adv) as a biotemplate, was achieved. This novel and simple biotemplating method can be summarized as direct co-incubation of the template Adv and PtCl4 solution, followed by the reduction of the co-incubation solution using NaBH4. The prepared Adv–PtNSs were then characterized by TEM, XRD and FTIR. The TEM results indicated that Adv–PtNSs, with good morphologies and monodispersity, can be obtained by controlling the concentration of PtCl4 as 7.5 mM, and the obtained Adv–PtNSs were about 100 nm. The results of XRD and FITR demonstrated that the prepared Adv–PtNSs were in a face-centered cubic structure, and the combination between the Adv and platinum complex ions mainly depended on –NH groups. In addition, the biocompatibilities of the prepared Adv–PtNSs to H9c2 cells were investigated. MTT assay results showed that as-prepared Adv–PtNSs had relatively high biocompatibilities, and caused almost no harm to H9c2 cells. Therefore, Adv–PtNSs have great potential as bioelectrode materials for monitoring the states of organisms.

A novel biotemplating method for fabricating gold nanoshells (AuNSs) through direct co-incubation of AuCl3 solution and an adenovirus shuttle vector-GFP (Adv) template in water, followed by the reduction of the mixture using fresh NaBH4, has been investigated in this paper. For comparison, different adenovirus-templated gold nanoshells (Adv-AuNSs) were prepared by modifying Adv with chitosan or changing the ionic conditions of the reaction system. The morphology and structure of the prepared AuNSs were characterized using transmission electron microscopy (TEM) and X-ray diffraction (XRD). The result indicated that Adv-AuNSs prepared by co-incubation of naked Adv and 7.5 mM AuCl3 solution had a uniform structure of approximately 120 nm diameter and face-centered cubic (fcc) crystal structure in the XRD pattern. A study of the biocompatibility of the prepared Adv-AuNSs demonstrated that there was no significant cytotoxicity. In addition, the photothermal therapy efficacy of the Adv-AuNSs on tumor cells was investigated in detail, revealing that all tumor cells could be killed when the power of near-infrared light irradiation was 4 W cm−2. Therefore, the prepared Adv-AuNSs will have very promising applications in the photothermal therapy of tumors.

A facile method was reported for preparing self-assembly Pt nanochains (PtNCs) by using octreotide acetate (AOC) as template in aqueous environment at room temperature. The influence of pH values on the reaction system was examined, and other synthesis parameters were optimized in order to prepare AOC-templated Pt nanoparticle arrays with high electrocatalytic activities. AOC was found with diameters in the range of 50±5 nm at pH 2.0/9.0, while the diameter of AOC was in the range of 20±5 nm under the condition of pH 4.0. Catalytic activities of the PtNCs prepared with different conditions were investigated, and the results demonstrated that the PtNCs catalyst prepared at pH 4 had higher catalytic activities in relative to those prepared at other conditions. Hence, the PtNCs will be a good anode catalyst candidate for direct methanol fuel cells.

As the widely use of gold nanoparticles (AuNPs) in drug delivery, the precise control on the size and morphology of the AuNPs is urgently required. In this scenario, traditional synthesis methods cannot meet current requirement because of their inherent defects. We have depicted here a novel method for fabricating monodispersed large size gold nanoparticles, based on the self-assembly of bacitracin. The AuNPs could be facilely, low-cost, and green synthesized with repeatability and controllability in this method. The Bac gold nanoparticles (Bac-AuNPs), composed by bacitracin core and gold shell, exhibited a spherical morphology in TEM and a face-centered cubic crystal structure in X-Ray diffraction and selected area electron diffraction. The mean diameter of the Bac-AuNPs was 89nm. The nanoparticles were mono-dispersed and the zeta potential of the nanoparticles was 4.1±0.64mV. Notably, in cell viability assay, the Bac-AuNPs showed less toxicity to HepG2 cells and HEK293 cells compared to small size AuNPs. Collectively, the size, rheological characteristic and the biocompatibility supported the use of the gold nanoparticles as intracellular delivery vehicles for drug delivery, especially for tumor therapy. And this study could provide a maneuverable, controllable and green strategy for the synthesis of AuNPs, which would be applied in disease diagnosis and therapy with biosafety.

Due to the dependence on the morphology, size and composition of Pt-based nanomaterials on their catalytic properties, rational design can improve the utilization efficiency and catalytic performance of Pt. As inspired by this, the ultralong Pt nanowires (ULPtNWs) with a diameter of 25 nm were prepared by a mild, green and direct peptide mediated biological template method. Impressively, ULPtNWs with a large electrochemical active surface area (57.2 m2 g-1) were obtained, exhibiting that the peak current density for the methanol oxidation was approximately three-fold better than commercial Pt/C catalyst owing to the high aspect ratio (1.6 × 103 or more). Additionally, the excellent poison resistance of the product was demonstrated, which can be attributed to the high (111) plane. These enhancements indicate that ULPtNWs as a promising catalyst have broad application prospects in the field of direct methanol fuel cells or other electrocatalysis.