A nanochitosan-D-galactose formulation increases the accumulation of primaquine in the liver

Primaquine is the mainstream antimalarial drug to prevent Plasmodium vivax relapses. However, this drug can induce hemolysis in patients with glucose-6-phosphate dehydrogenase deficiency. Nanostructure formulations of primaquine loaded with D-galactose were used as a strategy to target the drug to the liver and decrease the hemolytic risks. Nanoemulsion (NE-Pq) and nanochitosan (NQ-Pq) formulations of primaquine diphosphate containing D-galactose were prepared and characterized by their physicochemistry properties. Pharmacokinetic and biodistribution studies were conducted using Swiss Webster mice. A single dose of 10 mg/kg of each nanoformulation or free primaquine solution was administered by gavage to the animals, which were killed at 0.5, 1, 2, 4, 8, and 24 hours. Blood samples and tissues were collected, processed, and analyzed by high-performance liquid chromatography. The nanoformulation showed sizes around 200 nm (NE-Pq) and 400 nm (NQ-Pq) and physicochemical stability for over 30 days. Free primaquine solution achieved higher primaquine Cmax in the liver than NE-Pq or NQ-Pq at 0.5 hours. However, the half-life and mean residence time (MRT) of primaquine in the liver were three times higher with the NQ-Pq formulation than with free primaquine, and the volume distribution was four times higher. Conversely, primaquine's half-life, MRT, and volume distribution in the plasma were lower for NQ-Pq than for free primaquine. NE-Pq, on the other hand, accumulated more in the lungs but not in the liver. Galactose-coated primaquine nanochitosan formulation showed increased drug targeting to the liver compared to free primaquine and may represent a promising strategy for a more efficient and safer radical cure for vivax malaria.

Systemic availability of prophylactic cefuroxime in patients submitted to coronary artery bypass grafting with cardiopulmonary bypass

Cardiopulmonary bypass and hypothermia (HCPB) is a procedure commonly used during heart surgery, representing a risk factor for the patient by promoting extensive haemodilution and profound physiological changes. Cefuroxime is used for the prevention of infection following heart surgery, and several dose schemes have been suggested for prophylaxis with cefuroxime. The objective of the present study was to assess, in a comparative manner, the systemic availability of cefuroxime administered intravascularly as a bolus dose of 1.5 g to 17 patients having heart surgery with or without HCPB. Plasma cefuroxime concentrations were determined by high-pressure liquid chromatography-UV, and the following values, expressed as medians, were obtained for the study group compared with controls: 69.1 vs. 62.7 mg/L (1st h), 35.8 vs. 26.0mg/L (3rd h), 14.6 vs. 8.7 mg/L (6th h, P<0.05), 6.1 vs. 3.0mg/L (9th h, P<0.05) and 2.6 vs. 1.0mg/L (12th h, P<0.05). Despite the differences recorded during the study period as a consequence of HCPB, low antibiotic concentrations were found as early as 6h post dose for both groups investigated. Thus, the low systemic availability of cefuroxime after the administration of a 1.5-g dose may not protect against postoperative infections. The data obtained permit us to recommend a change in the dose scheme in order to maintain adequate plasma levels of cefuroxime.