Tag Archives: Fundação de Amparo à Pesquisa do Estado de São Paulo

Brazilian company encapsulates silver nanoparticles in milk packaging for longer product life

They’ve managed to double the shelf life for fresh milk from seven days to 15 be encapsulating silver nanoparticles in ceramic microparticles in packaging for fresh milk. From an Aug. 4, 2015 news item on Nanowerk,

Agrindus, an agribusiness company located in São Carlos, São Paulo state, Brazil, has increased the shelf life of grade A pasteurized fresh whole milk from seven to 15 days.

This feat was achieved by incorporating silver-based microparticles with bactericidal, antimicrobial and self-sterilizing properties into the rigid plastic bottles used as packaging for the milk.

The technology was developed by Nanox, also located in São Carlos. Supported by FAPESP’s Innovative Research in Small Business (PIPE) program, the nanotechnology company is a spinoff from the Center for Research and Development of Functional Materials (CDFM), one of the Research, Innovation and Dissemination Centers (RIDCs) supported by São Paulo Research Foundation (FAPESP).

“We already knew use of our antimicrobial and bactericidal material in rigid or flexible plastic food packaging improves conservation and extends shelf life. So we decided to test it in the polyethylene used to bottle grade A fresh milk in Brazil. The result was that we more than doubled the product’s shelf life solely by adding the material to the packaging, without mixing any additives with the milk”, said the Nanox CEO, Luiz Pagotto Simões.

An Aug. 4, 2015 Fundação de Amparo à Pesquisa do Estado de São Paulo news release on EurekAlert, which originated the news item, expands on the theme,

According to Simões, the microparticles are included as a powder in the polyethylene preform that is used to make plastic bottles by blow or injection molding. The microparticles are inert, so there is no risk of their detaching from the packaging and coming into contact with the milk.

Tests of the material’s effectiveness in extending the shelf life of fresh milk were performed for a year by Agrindus, Nanox and independent laboratories. “Only after shelf life extension had been certified did we decide to bring the material to market,” Simões said.

In addition to Agrindus, the material is also being tested by two other dairies that distribute fresh milk in plastic bottles in São Paulo and Minas Gerais and by dairies in the Brazilian southern region that sell fresh milk in flexible plastic packaging.

“In milk bags, the material is capable of extending shelf life from four to ten days,” he said.

Nanox plans to market the product in Europe and the United States, where much larger volumes of fresh milk are consumed than in Brazil.

The kind of milk most consumed in Brazil is ultra-high temperature (UHT), or “long life” milk, which is sterilized at temperatures ranging from 130°C to 150°C for two to four seconds to kill most of the bacterial spores. Unopened UHT milk has a shelf life of up to four months at room temperature.

Whole milk, known as grade A in Brazil, is pasteurized at much lower temperatures by the farmer and requires refrigeration. “Doubling the shelf life of whole milk translates into significant benefits in terms of logistics, storage, quality and food safety,” Simões said.

Countless applications

The silver-based microparticles developed by Nanox are currently being used in several other products other than packaging for fresh milk, including plastic utensils, PVC film for wrapping food, toilet seats, shoe insoles, hair dryers and flatirons, paints, resins, and ceramics, as well as coatings for medical and dental instruments such as grippers, drills and scalpels.

But the company’s largest markets today are makers of rugs, carpets, and white goods, such as refrigerators, drinking fountains and air conditioners.

“We’ve supplied several products to white goods manufacturers since 2007,” Simões said. “This material is shipped to the leading players in the market.” Nanox currently exports the product to 12 countries via local distributors in Chile, China, Colombia, Italy, Mexico and Japan, among others.

The company now wants to enter the United States, having won approval in 2013 from the Food & Drug Administration (FDA) to market the bactericidal material for use in food packaging.

“We’ve applied for clearance by the EPA [the Environmental Protection Agency] so that we can sell to a larger proportion of the US market,” Simões said.

Neither Brazil nor the US has clear legislation on the use of particles at the nanometer scale [a billionth of a meter] in products that involve contact with food, so the company uses nanotechnology processes that result in silver-based particles at the micrometer scale [a millionth of a meter], he said.

The core of the technology consists of coating ceramic particles made of silica with silver nanoparticles. The silver nanoparticles bond with the ceramic matrix to form a micrometre scale composite with bactericidal properties.

“The combination of silver particles with a ceramic matrix produces synergistic effects. Silver has bactericidal properties, and while silica doesn’t, it boosts those of the silver and helps control the release of silver particles to kill bacteria,” he said.

I wonder if they’ve done any ‘life cycle’ analysis. In other words, what happens to the packaging and those encapsulated silver nanoparticles when the milk jugs (and Nanox’s other silver-based products) are recycled or put in the garbage dump?

You can find out more about Nanox (English language version) here and about Agrindus, a division of Letti?, (you will need Portuguese language reading skills) here.

Herbicide nanometric sensor could help diagnose multiple sclerosis

This research into nanometric sensors and multiple sclerosis comes from Brazil. According to a June 23, 2015 news item on Nanowerk (Note: A link has been removed),

The early diagnosis of certain types of cancer, as well as nervous system diseases such as multiple sclerosis and neuromyelitis optica, may soon be facilitated by the use of a nanosensor capable of identifying biomarkers of these pathological conditions (“A Nanobiosensor Based on 4-Hydroxyphenylpyruvate Dioxygenase Enzyme for Mesotrione Detection”).

The nanobiosensor was developed at the Federal University of São Carlos (UFSCar), Sorocaba, in partnership with the São Paulo Federal Institute of Education, Science & Technology (IFSP), Itapetininga, São Paulo State, Brazil. It was originally designed to detect herbicides, heavy metals and other pollutants.

A June 23, 2015 Fundação de Amparo à Pesquisa do Estado de São Paulo news release on EurekAlert, which originated the news item, describes the sensor as it was originally used and explains its new function as a diagnostic tool for multiple sclerosis and other diseases,

“It’s a highly sensitive device, which we developed in collaboration with Alberto Luís Dario Moreau, a professor at IFSP. “We were able to increase sensitivity dramatically by going down to the nanometric scale,” said physicist Fábio de Lima Leite, a professor at UFSCar and the coordinator of the research group.

The nanobiosensor consists of a silicon nitride (Si3N4) or silicon (Si) nanoprobe with a molecular-scale elastic constant and a nanotip coupled to an enzyme, protein or other molecule.

When this molecule touches a target of interest, such as an antibody or antigen, the probe bends as the two molecules adhere. The deflection is detected and measured by the device, enabling scientists to identify the target.

“We started by detecting herbicides and heavy metals. Now we’re testing the device for use in detecting target molecules typical of nervous system diseases, in partnership with colleagues at leading centers of research on demyelinating diseases of the central nervous system”

The migration from herbicide detection to antibody detection was motivated mainly by the difficulty of diagnosing demyelinating diseases, cancer and other chronic diseases before they have advanced beyond an initial stage.

The criteria for establishing a diagnosis of multiple sclerosis or neuromyelitis optica are clinical (supplemented by MRI scans), and patients do not always present with a characteristic clinical picture. More precise diagnosis entails ruling out several other diseases.

The development of nanodevices will be of assistance in identifying these diseases and reducing the chances of false diagnosis.

The procedure can be as simple as placing a drop of the patient’s cerebrospinal fluid on a glass slide and observing its interaction with the nanobiosensor.

“If the interaction is low, we’ll be able to rule out multiple sclerosis with great confidence,” Leite said. “High interaction will indicate that the person is very likely to have the disease.” In this case, further testing would be required to exclude the possibility of a false positive.

“Different nervous system diseases have highly similar symptoms. Multiple sclerosis and neuromyelitis optica are just two examples. Even specialists experience difficulties or take a long time to diagnose them. Our technique would provide a differential diagnostic tool,” Leite said.

The next step for the group is to research biomarkers for these diseases that have not been completely mapped, including antibodies and antigens, among others. The group has begun tests for the detection of head and neck cancer.

Here’s a link to and a citation for the paper,

A Nanobiosensor Based on 4-Hydroxyphenylpyruvate Dioxygenase Enzyme for Mesotrione Detection by P. Soto Garcia, A.L.D Moreau, J.C. Magalhaes Ierich,  A.C Araujo Vig, A.M. Higa, G.S. Oliveira, F. Camargo Abdalla, M. Hausen, & F.L. Leite. Sensors Journal, IEEE  (Volume:15 ,  Issue: 4) pp. 2106 – 2113 Date of Publication: 20 November 2014 Date of Current Version: 27 January 2015 Issue Date: April 2015  DOI 10.1109/JSEN.2014.2371773

This paper is behind a paywall.