Polypyrrole/graphene oxide nanocomposite-coated fiber located in a capillary tube reinforced by a vacuum system for assessment of oxidative stability of edible oils

1. A vacuum-assisted coated fiber located in a capillary tube (VA-CFLCT) system comprising:

a first capillary tube including a first end and a second end;

a second capillary tube disposed adjacent to the first capillary tube;

a stainless-steel fiber disposed in an interior space of the first capillary tube;

an extraction vial including a first opening and a second opening, the extraction vial configured for extraction of an analyte;

a sorbent coated on the stainless-steel fiber, the sorbent being configured to entrap the analyte, the analyte being attached to a sample that is injected into the extraction vial;

a first cover configured to cover the first opening of the extraction vial, the first cover including a first aperture, a second aperture, and a third aperture, the first aperture being configured to receive the first capillary tube within an interior space of the extraction vial, the second aperture being configured to receive the second capillary tube within the interior space of the extraction vial, and the third aperture being configured to receive a hollow needle for injecting the sample into the extraction vial;

a pump including an inlet and an outlet, the inlet coupled to the second end of the first capillary tube, the pump being configured to circulate the extracted analyte though the first capillary tube and the second capillary tube to improve analyte adsorption on the sorbent inside the first capillary tube; and

a vacuum device configured to evacuate the interior space of the extraction vial and improve the efficiency of the analyte extraction process, wherein:

the vacuum device includes a valve and a vacuum pump,

a connection tube is configured to connect the vacuum pump to the second opening of the extraction vial,

the vacuum pump is in fluid communication with the extraction vial and is configured to provide a vacuum within the interior space of the extraction vial, and

the valve being configured to operate between an open position and a closed position, wherein in the closed position the valve disables communication between the vacuum pump and the extraction vial and in the open position the valve enables the communication between the vacuum pump and the extraction vial.

2. The system of claim 1 , wherein the sorbent is polypyrrole and graphene oxide nanocomposite.

3. The system of claim 1 , wherein the sorbent is made by a 2-electrode electrochemical polymerization/electrophoretic deposition technique.

4. The system of claim 1 , wherein the first capillary tube comprises stainless steel.

5. A method for sampling analytes comprising:

synthesizing a nanosorbent;

applying the nanosorbent as a coating on at least a portion of a stainless-steel fiber, thereby producing a nanosorbent-coated stainless-steel fiber;

inserting the nanosorbent-coated stainless-steel fiber into a first capillary tube reinforced by a vacuum system;

inserting a first end of the first capillary tube into a first end of a vacuum flask via a first aperture;

inserting a first end of a second capillary tube into the first end of the vacuum flask via a second aperture;

inserting a hollow needle into the first end of the vacuum flask via a third aperture;

securing a second end of the first capillary tube to a peristaltic pump;

securing a second end of the second capillary tube to the peristaltic pump;

securing a first end of a valve to a second end of the vacuum flask, the being valve configured to control a vacuum process, the valve including an open position and a closed position;

securing a second end of the valve to a vacuum pump;

creating a vacuum inside the vacuum flask by turning on the vacuum pump and switching the valve to the open position;

switching the valve to the closed position and turning the vacuum pump off, thereby maintaining the vacuum inside the vacuum flask;

injecting a sample into the vacuum flask via the hollow needle; and,

circulating the sample inside the first capillary tube and the second capillary tube by use of the peristaltic pump.

6. The method of claim 5 , wherein the nanosorbent is a polypyrrole and graphene oxide nanocomposite.

7. The method of claim 5 , wherein the nanosorbent is made by a 2-electrode electrochemical polymerization/electrophoretic deposition technique.

8. The method of claim 5 , wherein at least the first capillary tube comprises stainless steel.