Encapsulating gold nanomaterials into size-controlled human serum albumin nanoparticles for cancer therapy platforms.

Progress has been made in using human serum albumin nanoparticles (HSAPs) as promising colloidal carrier systems for early detection and targeted treatment of cancer and other diseases. Despite this success, there is a current lack of multi-functional HSAP hybrids that offer combinational therapies. The size of the HSAPs has crucial importance on drug loading and in vivo performance and has previously been controlled via manipulation of pH and cross-linking parameters.

Physical and photoelectrochemical properties of Zr-doped hematite nanorod arrays.

This work examines the effect of Zr(4+) ions on the physical and photoelectrochemical (PEC) properties of hematite (α-Fe2O3) nanorod arrays grown in an aqueous solution containing zirconyl nitrate (ZrO(NO3)2) as a dopant precursor. The concentration of ZrO(NO3)2 in the precursor solution influenced both the film thickness and the Zr(4+) concentration in the resulting films. Zr doping was found to enhance the photocurrent for water splitting; the highest photocurrent at 1.

Exciton dynamics in semiconductor nanocrystals.

This review article provides an overview of recent advances in the study and understanding of dynamics of excitons in semiconductor nanocrystals (NCs) or quantum dots (QDs). Emphasis is placed on the relationship between exciton dynamics and optical properties, both linear and nonlinear. We also focus on the unique aspects of exciton dynamics in semiconductor NCs as compared to those in bulk crystals.

Ultrafast Exciton Dynamics in Silicon Nanowires.

Ultrafast exciton dynamics in one-dimensional (1D) silicon nanowires (SiNWs) have been investigated using femtosecond transient absorption techniques. A strong transient bleach feature was observed from 500 to 770 nm following excitation at 470 nm. The bleach recovery was dominated by an extremely fast feature that can be fit to a triple exponential with time constants of 0.

Direct molecule-specific glucose detection by Raman spectroscopy based on photonic crystal fiber.

This paper reports the first step toward the development of a glucose biosensor based on Raman spectroscopy and a photonic crystal fiber (PCF) probe. Historically, it has been very challenging to detect glucose directly by Raman spectroscopy due to its inherently small Raman scattering cross-section. In this work, we report the first quantitative glucose Raman detection in the physiological concentration range (0-25 mM) with a low laser power (2 mW), a short integration time (30 s), and an extremely small sampling volume (~50 nL) using the highly sensitive liquid-filled PCF probe.

Electron enrichment in 3d transition metal oxide hetero-nanostructures.

Direct experimental observation of spontaneous electron enrichment of metal d orbitals in a new transition metal oxide heterostructure with nanoscale dimensionality is reported. Aqueous chemical synthesis and vapor phase deposition are combined to fabricate oriented arrays of high-interfacial-area hetero-nanostructures comprised of titanium oxide and iron oxide nanomaterials. Synchrotron-based soft X-ray spectroscopy techniques with high spectral resolution are utilized to directly probe the titanium and oxygen orbital character of the interfacial region's occupied and unoccupied densities of states.

Facile synthesis of highly photoactive α-Fe₂O₃-based films for water oxidation.

This work reports a facile method for preparing highly photoactive α-Fe(2)O(3) films as well as their implementation as photoanodes for water oxidation. Transparent α-Fe(2)O(3) films were prepared by a new deposition-annealing (DA) process using nontoxic iron(III) chloride as the Fe precursor, followed by annealing at 550 °C in air. Ti-doped α-Fe(2)O(3) films were prepared by the same method, with titanium butoxide added as the Ti precursor.

Sn-doped hematite nanostructures for photoelectrochemical water splitting.

We report on the synthesis and characterization of Sn-doped hematite nanowires and nanocorals as well as their implementation as photoanodes for photoelectrochemical water splitting. The hematite nanowires were prepared on a fluorine-doped tin oxide (FTO) substrate by a hydrothermal method, followed by high temperature sintering in air to incorporate Sn, diffused from the FTO substrate, as a dopant. Sn-doped hematite nanocorals were prepared by the same method, by adding tin(IV) chloride as the Sn precursor.

SERS spectroscopy and SERS imaging of Shewanella oneidensis using silver nanoparticles and nanowires.

Facile and reproducible SERS signals from Shewanella oneidensis were obtained utilizing silver nanoparticles (AgNPs) and silver nanowires (AgNWs). Additionally, SERS images identify the distribution of SERS hot-spots. One important observation is the synergistically enhanced SERS signal when AgNPs and AgNWs are used in conjunction, due to constructively enhanced electromagnetic field.