Evaluation of lipid metabolism imbalance in HIV-infected patients with metabolic disorders using high-performance liquid chromatography-tandem mass spectrometry.

Human immunodeficiency virus (HIV) infection and highly active antiretroviral therapy use are associated with the disruption of lipid and glucose metabolism. Herein, a sensitive and robust high-performance liquid chromatography-tandem mass spectrometry method for the quantitation of lysophosphatidylcholines (LPCs) and acylcarnitines (ACs) in human blood serum was developed and validated to investigate them as markers of metabolic disorders in HIV-infected patients. Under optimal extraction and detection conditions, the lower limits of quantification reached 5 ng/mL (LPCs) and 0.1 ng/mL (ACs), and precision and accuracy for both intra- and inter-day analyses were generally below 15%. Serum samples were stable for at least six months when stored at - 80 °C and for at least 12 h when stored at 4 °C or 25 °C. We investigated inter-group differences and associations between the biomarkers and observed a particular volatilitytrend of LPCs and ACs for HIV-infected patients with metabolic disorders. Thus, the developed method can be used for the rapid and sensitive quantitation of LPCs and ACs in vivo to further appraise the process of HIV infection, evaluate interveningmeasures, conduct mechanistic investigations, and further study the utility of LPCs and ACs as biomarkers of HIV infection coupled with metabolic disorders.

Determination of photocyanine in human serum by HPLC and application to pharmacokinetic study.

Photocyanine, a novel amphoteric phthalocyanine drug, showed favorable anticancer activity in vivo. Pharmacokinetic study in cancer patients is an important component in dose administration choice. In this study, a rapid, sensitive analytical method based on high-performance liquid chromatography with ultraviolet detection was developed and validated for the determination of four isomers of photocyanine (FD1-4) in cancer patients. Sample preparation involved liquid-liquid extraction with a combination of ultrasound and N,N-dimethyl formamide. Calibration curves (1/x(2)) offered satisfactory linearity for the four isomers of photocyanine. The lower limit of quantification (LLOQ) for FD1-3 isomers was 30 ng/mL, and LLOQ for FD-4 was 5 ng/mL. Inter- and intra-day accuracies for four isomers ranged from 96.6 to 105.5%, and 95.0 to 103.6%, respectively. Inter- and intra-day precision ranged from 4.8 to 8.9%, and 3.6 to 12.2%, respectively. Stability studies showed that photocyanine was stable. This method was successfully used to quantify photocyanine in a pharmacokinetic study in which a single-dose of photocyanine (0.1 mg/kg) was intravenously administered to patients with cancer. On the basis of the discovery that photocyanine has a half-life of 57.5 h in vivo, we suggest that avoiding light for a longer period is essential for patients undergoing photocyanine therapy.