Dispersive Micro-Solid Phase Extraction for Sensitive Determination of Methotrexate from Human Saliva Followed by Spectrophotometric Method.

For biological assessing of hospital personnel occupationally exposed to antineoplastic drugs, highly sensitive and accurate methods are required. Methotrexate (MTX) is an anticancer agent that is widely used in a variety of human cancers. For the first time, dispersive-micro solid phase extraction (D-µ-SPE) has been applied for determination of low levels of MTX in saliva samples. The method is based on rapid extraction of MTX using graphene oxide adsorbent. The sample preparation time is decreased by the fact that the adsorbent dispersed in the sample solution and extraction equilibrium can be reached very fast. This significant feature which obtained with this method is of key interest for routine trace laboratory analysis. The influence of different variables on D-µ-SPE was investigated. Under optimum conditions, the calibration graph was linear over the range of 10-1000 ng/ml. The relative standard deviations are better than 9.0%. The proposed method was successfully applied for the determination of MTX in patient samples.

Synthesis and characterization of ionic liquid functionalized polymers for drug delivery of an anti-inflammatory drug.

Polymeric forms of ionic liquids have many potential applications because of their ionic nature. Two ionic liquid monomers, 1-(4-vinylbenzyl)-3-methyl imidazolium hexafluorophosphate (VMIH) and 1-(4-vinylbenzyl)-4-(dimethylamino)-pyridinium hexafluorophosphate (VDPH), were synthesized through the quaternization of N-methylimidazole and 4-(dimethylamino) pyridine with 4-vinylbenzylchloride, respectively, and a subsequent anion exchange reaction with potassium hexafluorophosphate. The homopolymers of VMIH, VDPH, and its copolymers with methyl styrene (in various mole ratios) were synthesized by free radical polymerizations at 70 °C using α,α'-azobis(isobutyronitrile) as an initiator. Anionic drug molecule, naproxen (an anti-inflammatory drug), was effectively loaded into these positive charges polymers (PCP) and remained inside of the PCP under acidic environment (pH 2-6.5). The amount of loading of drug was increased with increasing positive charge densities resulting from the increasing number of ionic liquids groups. PCP as a controllable release of anionic drug molecules can be used as an oral delivery drug systems targeting at intestine. This drug can be remained trapped in the polymers when passing through the acidic and neutral environment and be released in intestine, where the environmental pH is close to basic.