Materials and methods for the detection of trace amounts of substances in biological and environmental samples
View Patent ↗The subject invention provides chemical compositions and synthesis strategies to create molecularly imprinted polymers (MIPs) via sol-gel processes. In a specific embodiment, the subject invention utilizes a(n) organic, inorganic, or metallic template analyte to create a hybrid organic-inorganic or inorganic three-dimensional network possessing cavities complementary to the shape, size, and functional orientation of the template molecule or ions. The subject invention further pertains to the use of the novel MIPs as selective solid phase extraction (SPE) sorbents for pre-concentration and clean-up of trace substances in biological and environmental samples. Synthesis of other molecularly imprinted polymers with environmental, pharmaceutical, chemical, clinical, toxicological, and national security implications can be conducted in accordance with the teachings of the subject invention.
1. A method of synthesizing a molecularly imprinted polymer (MIP) matrix, comprising:
mixing chloramphenicol (CAP) with more than one sol-gel precursor to form a polymer complex, wherein the sol-gel precursors comprise saline groups;
hydrolyzing the sol-gel precursors and a cross-linking agent with a hydrolytic agent in the presence of a reaction catalyst;
combining the hydrolyzed sol-gel precursors with the polymer complex;
allowing the sol-gel polymer complex to form surrounding the target analyte; and
extracting the target analyte using a solvent, leaving behind molecular cavities in the polymer network that are complementary in size, shape, and functionality to the target analyte.
2. The method according to claim 1 , the sol-gel precursors being 3-aminopropyltriethoxysilane and triethoxyphenylsilane.
3. The method according to claim 1 , the cross-linking agent being tetramethyl orthosilicate.
4. The method according to claim 1 , the reaction catalyst being an acid.
5. The method according to claim 4 , the catalyst being hydrochloric acid.
6. The method according to claim 1 , the hydrolytic agent being water.
7. The method according to claim 1 , the solvent being selected from methanol, ethanol, isopropanol, formic acid, acetonitrile, acetone, and mixtures thereof.
8. A sol-gel MIP sorbent material prepared using the method according to claim 1 .
9. The material according to claim 8 , said material being capable of detecting the target analyte in a sample but being indifferent to other species present in the same sample.
10. A method of detecting CAP in a fluid sample, comprising:
providing a sol-gel polymer sorbent material imprinted molecularly with CAP, the sorbent material being prepared according to claim 1 passing the fluid sample through the sorbent material; and
detecting CAP in the eluent of the sorbent material.
11. The method according to claim 10 , performed in an apparatus selected from a syringe and a solid-phase extraction cartridge.
12. The method according to claim 10 , the sample being selected from physiological fluids, forensic specimens, environmental pollutants, food samples, beverage samples, pharmaceutical samples, chemical samples, drug residues and metabolites thereof, and poison residues and metabolites thereof.
13. The method according to claim 10 , further comprising quantification of the concentration of the CAP in the sample.
14. A method of detecting chloramphenicol (CAP) in a sample, comprising:
providing a molecularly imprinted polymer (MIP) sorbent material, the sorbent material being prepared via a sol-gel process employing CAP as the target analyte, 3-aminopropyltriethoxysilane and triethoxyphenylsilane as sol-gel precursors, tetramethyl orthosilicate as a cross-linking agent, hydrochloric acid as a reaction catalyst, water as a hydrolytic agent, and isopropanol and methanol as solvents;
packaging dried MIP sorbent material in an extraction apparatus selected from a syringe and a solid-phase extraction cartridge;
providing a fluid sample;
passing the fluid sample through the extraction apparatus; and
quantifying the concentration of CAP in the eluent of the MIP sorbent material.
15. The method according to claim 14 , the eluent of the sorbent material being obtained using a solvent selected from methanol, ethanol, isopropanol, formic acid, acetonitrile, acetone, and a mixture thereof.
16. The method according to claim 14 , the sample being selected from physiological fluids, forensic specimens, environmental pollutants, food samples, beverage samples, pharmaceutical samples, chemical samples, drug residues and metabolites thereof, and poison residues and metabolites thereof.