Food Safety Evaluation of Recombinant Humanized Type III Collagen Produced by Komagataella phaffii SMD1168-2COL3.

Collagens are biofunctional proteins that have been widely used in many fields, including biomedical, cosmetics, and skin care for their value in maintaining the integrity of cellular membranes. Collagens are also commonly consumed in foods and provide a source of protein and amino acids. As part of the safety assessment for this particular recombinant humanized type III (RHTypeIII) collagen produced by Komagataella phaffii SMD1168-2COL3, a series of toxicological tests were conducted.

Discovery of systematic responses and potential biomarkers induced by ochratoxin A using metabolomics.

Ochratoxin A (OTA) is known to be nephrotoxic and hepatotoxic in rodents when exposed orally. To understand the systematic responses to OTA exposure, GC-MS- and (1)H-NMR-based metabolomic techniques together with histopathological assessments were applied to analyse the urine and plasma of OTA-exposed rats. It was found that OTA exposure caused significant elevation of amino acids (alanine, glycine, leucine etc.

MicroRNA profiling of rats with ochratoxin A nephrotoxicity.

Background: Nephrotoxicity is the most prominent one among the various toxicities of ochratoxin A (OTA). MicroRNAs (miRNAs) are small non-coding RNAs that have an impact on a wide range of biological processes by regulating gene expression at post-transcriptional level or protein systhesis level. The objective of this study is to analyze miRNA profiling in the kidneys of rats gavaged with OTA.

Programmable nanoparticle ensembles via high-throughput directed self-assembly.

We present a simple and facile strategy for the directed self-assembly of nanoparticles into complex geometries using a minimal set of post guiding features patterned on a substrate. This understanding is based on extensive studies of nanoparticle self-assembly into linear, dense-packed, circular, and star-shaped ensembles when coated onto patterned substrates of predefined post arrays. We determined the conditions under which nanoparticles assemble and "connect" two adjacent post features, thereby forming the desired shapes.

High-throughput directed self-assembly of core-shell ferrimagnetic nanoparticle arrays.

Magnetic nanoparticles (MNPs) provide a set of building blocks for constructing stimuli-responsive nanoscale materials with properties that are unique to this scale. The size and the composition of MNPs are tunable to meet the requirements for a range of applications including biosensors and data storage. Although many of these technologies would significantly benefit from the organization of nanoparticles into higher-order architectures, the precise placement and arrangement of nanoparticles over large areas of a surface remain a challenge.

Monodisperse cobalt ferrite nanomagnets with uniform silica coatings.

Ferro- and ferrimagnetic nanoparticles are difficult to manipulate in solution as a consequence of the formation of magnetically induced nanoparticle aggregates, which hamper the utility of these particles for applications ranging from data storage to bionanotechnology. Nonmagnetic shells that encapsulate these magnetic particles can reduce the interparticle magnetic interactions and improve the dispersibility of the nanoparticles in solution. A route to create uniform silica shells around individual cobalt ferrite nanoparticles--which uses poly(acrylic acid) to bind to the nanoparticle surface and inhibit nanoparticle aggregation prior to the addition of a silica precursor--was developed.

Self-assembled ferrimagnet--polymer composites for magnetic recording media.

A self-assembled magnetic recording medium was created using colloidal ferrimagnetic building blocks. Monodisperse cobalt ferrite nanoparticles (CoFe(2)O(4)) were synthesized using solution-based methods and then stabilized in solution using the amphiphilic diblock copolymer, poly(acrylic acid)-b-poly(styrene) (PAA-PS). The acid groups of the acrylate block bound the polymer to the nanoparticle surface via multivalent interactions, while the styrene block afforded the magnetic nanoparticle--polymer complex solubility in organic solvents.

Magnetically-responsive self assembled composites.

This tutorial review summarizes the recent advances on the self assembly of magnetic nanoparticles into one-, two-, and three-dimensional architectures using synthetic polymers and biopolymers. The materials have unique stimuli-responsive behavior that emerge in response to internal and external magnetic fields. For example, magnetic fields can be used to elicit a magnetic response from the materials, whether the material rearranges in response to the external field, or provides information regarding the local environment of the nanoparticles.

Surface modification of gold nanorods through a place exchange reaction inside an ionic exchange resin.

A place exchange reaction between 11-mercaptoundecanoic acids (MUA) and cetyltrimethylammonium bromide (CTAB)-protected gold nanorods (GNRs) was conducted inside an ionic exchange resin; this modification resulted in functional gold nanorods soluble in both polar and nonpolar organic solvents.

A one-step highly sensitive method for DNA detection using dynamic light scattering.

A one-step homogeneous DNA detection method with high sensitivity was developed using gold nanoparticles (AuNPs) coupled with dynamic light scattering (DLS) measurement. Citrate-protected AuNPs with a diameter of 30 nm were first functionalized with two sets of single-stranded DNA probes and then used as optical probes for DNA detection. In the presence of target DNA, the hybridization between target DNA and the two nanoparticle probes caused the formation of nanoparticle dimers, trimers, and oligomers.

Photothermal ablation of amyloid aggregates by gold nanoparticles.

Amyloid peptide (Abeta) is found in the brain and blood of both healthy and diseased individuals alike. However, upon secondary structure transformation to a beta-sheet dominated conformation, the protein aggregates. These aggregates accumulate to form neuritic plaques that are implicated in the pathogenesis of Alzheimer's disease.

A one-step homogeneous immunoassay for cancer biomarker detection using gold nanoparticle probes coupled with dynamic light scattering.

A one-step homogeneous immunoassay for the detection of a prostate cancer biomarker, free-PSA (prostate specific antigen), was developed using gold nanoparticle probes coupled with dynamic light scattering (DLS) measurements. A spherical gold nanoparticle with a core diameter around 37 nm and a gold nanorod with a dimension of 40 by 10 nm were first conjugated with two different primary anti-PSA antibodies and then used as optical probes for the immunoassay. In the presence of antigen f-PSA in solution, the nanoparticles and nanorods aggregate together into pairs and oligomers through the formation of a sandwich type antibody-antigen-antibody linkage.

A study on gold nanoparticle synthesis using oleylamine as both reducing agent and protecting ligand.

The growth kinetics and mechanism of a gold nanoparticle synthesis using water as a single phase solvent and oleylamine as both reducing agent and monolayer protection agent were studied. FT-IR and 1H NMR spectroscopic analysis revealed a conversion of oleylamine ligands to oleylamides when gold(III) was reduced to gold(I) and gold atoms. During the reaction, it was found by UV-Vis absorption spectroscopy and transmission electron microscopic study that oleylamine ligands formed large complex aggregates with gold salt instantly upon mixing these two agents together.

Solid phase monofunctionalization of gold nanoparticles using ionic exchange resin as polymer support.

A solid phase modification method using anionic exchange resin as polymer support was developed for the synthesis of monofunctional gold nanoparticles. Based on a "catch and release" mechanism to control the number of functional groups attached to the nanoparticle surface, bifunctional thiol ligands with a carboxylic acid end group were first immobilized at a controlled density on anionic exchange resin through electrostatic interactions. Gold nanoparticles were then immobilized to the anionic exchange resin by a one-to-one place exchange reaction between resin-bound thiol ligands and butanethiol-protected gold nanoparticles in solution.

Optical limiting of a covalently bonded gold nanoparticle/polylysine hybrid material.

The optical limiting performance of a covalently bonded gold nanoparticle (approximately 2 nm)/polylysine hybrid material (AuNP-PLL) was investigated using 4.1 ns laser pulses at 532 nm. The hybrid material exhibits enhanced optical limiting in comparison to individual nanoparticles, presumably due to the interparticle electromagnetic interactions between particles in close proximity.

A nanoparticle-dendrimer conjugate prepared from a one-step chemical coupling of monofunctional nanoparticles with a dendrimer.

Gold nanoparticle-dendrimer conjugate clusters were prepared by a covalent coupling of monofunctional gold nanoparticles with a generation 5 PAMAM dendrimer.

A "nanonecklace" synthesized from monofunctionalized gold nanoparticles.

Gold nanoparticles with a single carboxylic acid group on the surface were prepared from a solid phase place exchange reaction and then coupled to polylysine using an in situ activation agent, diisopropylcarbodiimide (DIPCDI). The covalent amide bond linkage between the nanoparticles and polylysine and the ring closure of the polylysine chain have led to the formation of a nanoparticle/polymer hybrid material with "nanonecklace" structures.