RESUMEN
The use of nanomaterials in drug delivery has gained significant attention in recent years. In this project, we developed a novel localized surface plasmon resonance (LSPR) nanoprobe on single gold triangular nanoplates (AuNTs) for dynamic monitoring of the drug carrier release process. Graphene, as the drug carrier, could be immobilized on the AuNT surface through the π-π* stacking effect. Upon loading or releasing the model drug (doxorubicin, DOX), subtle changes in the local microenvironment's dielectric constant around the AuNTs induced notable red-shifts or blue-shifts in the LSPR scattering spectra of single AuNTs. Furthermore, the spectral shifts led to a continuous enhancement in the red channel of the dark field microscopy (DFM) images during the drug release process in vitro, demonstrating that the drug release system is not susceptible to potential confounding factors. These release kinetics results under different conditions could be well-fitted using the Higuchi desorption model, further proving that this nanoprobe could be employed for evaluating the controlled release ability of 2D nanocarriers. These findings are expected to inspire new ideas and technologies in the preparation of more effective drug carriers, making a significant contribution to the development of drug delivery nanosystems and nanomedicine.
Asunto(s)
Portadores de Fármacos , Sistemas de Liberación de Medicamentos , Doxorrubicina , Microscopía/métodos , Resonancia por Plasmón de Superficie/métodosRESUMEN
AIM: The aim of the current study was to characterize the pharmacokinetics (PK) and pharmacodynamics (PD) of cisatracurium in patients with severe mitral valve regurgitation (MR) during the anaesthetic induction period. METHODS: Thirty patients in the clinical trial were divided into two groups: the MR group (n = 15) and the control group (n = 15). Arterial blood samples were obtained before (time 0) and at 1, 2, 4, 6, 8, 10, 15 and 20 min after intravenous injection of 0.15 mg kg-1 cisatracurium. The degree of neuromuscular block was measured by train of four (TOF) testing. The concentration of cisatracurium in the plasma was determined by high-performance liquid chromatography. A conventional two-compartment model and integrated PK/PD model were applied to PK and PD data analysis, respectively. RESULTS: The results of PK model fitting demonstrated that severe MR reduced the distribution rate of cisatracurium from the central to peripheral compartment, resulting in a higher concentration of the drug in the plasma. The time to the maximal neuromuscular blocking effect of cisatracurium was delayed in the MR group (2.08 min in the control group vs. 4.12 min in the MR group). The PK/PD model indicated that the distribution rate of cisatracurium from the blood to the effect compartment was decreased in the MR group. CONCLUSIONS: The present study suggested that the PK and PD of cisatracurium were significantly altered in patients with severe MR. The study has the potential to improve the safety of anaesthetic induction in patients with severe MR through accurate prediction of the PD responses of cisatracurium using the established PK/PD model.
Asunto(s)
Atracurio/análogos & derivados , Insuficiencia de la Válvula Mitral/fisiopatología , Modelos Biológicos , Bloqueantes Neuromusculares/administración & dosificación , Adulto , Atracurio/administración & dosificación , Atracurio/farmacocinética , Atracurio/farmacología , Estudios de Casos y Controles , Cromatografía Líquida de Alta Presión , Femenino , Humanos , Inyecciones Intravenosas , Masculino , Persona de Mediana Edad , Bloqueantes Neuromusculares/farmacocinética , Bloqueantes Neuromusculares/farmacología , Índice de Severidad de la Enfermedad , Factores de TiempoRESUMEN
OBJECTIVE: To compare the pharmacokinetics of cisatracurium between normal weight patients and morbidly obese patients. METHODS: Twelve obese ASA I-II patients (BMI≥35 kg/m2) undergoing laparoscopic Roux-en-Y gastric bypass and 12 normal weight ASA I-II patients (BMI of 18.5-24 kg/m2) undergoing laparoscopic surgery were enrolled. The obese patients were given a cisatracurium dose of 0.15 mg/kg according to the fat-free mass (FFM), and the non-obese patients received a dose of 0.15 mg/kg according to the total body weight. Plasma concentrations of cisatracurium was monitored in the patients with high-performance liquid chromatography (HPLC) before anesthetic induction and at 1, 2, 4, 6, 8, 10, 12, 15, and 20 min after cisatracurium administration and the pharmacokinetic parameters were computed. SBP, DBP, HR, MAP, SpO2 and PetCO2 were recorded before anesthetic induction (T0) and at 1 min (T1), 2 min (T2), 4 min (T3) after cisatracurium administration. RESULTS: Compared with those measured at T0, SBP, DBP and MAP in the 2 groups were significantly decreased at the time points of T1-3 (P<0.05). Compared with the non-obese patients, the obese patients showed significantly increased Hct level (P<0.05). The total clearance, apparent volume of distribution, and distribution and elimination half-life of the drug were similar between the 2 groups (P>0.05). The plasma concentration of cisatracurium at T1-2 was significantly decreased in the obese patients compared with that in the non-obese patients (P<0.05). CONCLUSION: Cisatracurium doses according to fat-free mass is clinically reasonable for inducing anesthesia in morbidly obese patients, but due to a prolonged muscle relax onset time, the timing of tracheal intubation should be delayed by 1-2 min.
Asunto(s)
Anestesia , Atracurio/análogos & derivados , Derivación Gástrica , Obesidad Mórbida/sangre , Atracurio/farmacocinética , Semivida , Humanos , Laparoscopía , Factores de TiempoRESUMEN
OBJECTIVE: To investigate the correlation between arterial partial pressure of CO2 (PaCO2) and end expiratory tidal partial pressure of CO2 (Pet-CO2) in morbidly obese patients during anesthesia for laparoscopic gastric bypass surgery. METHODS: Forty morbidly obese patients with a body mass index (BMI) between 35 and 50 kg/m(2) underwent laparoscopic gastric bypass surgery under general anesthesia. PaCO2 and Pet-CO2 were measured after intubation and before induction of pneumoperitoneum (T0), at 30 min (T1), 60 min (T2), and 120 min (T3) during pneumoperitoneum, and at 30 min (T4) and 60 min (T5) after deflation. RESULTS: At each time point of measurement, Pet-CO2 was lower than PaCO2 in all the patients. PaCO2 and Pet-CO2 were positively correlated before, during, and after pneumoperitoneum (P<0.05). At a moderate pressure of CO2 pneumoperitoneum (16 mmHg), the level of correlation between PaCO2 and Pet-CO2 at T1, T2, and T3 differed from that before and after post-pneumoperitoneum. CONCLUSIONS: PaCO2 and Pet-CO2 are closely correlated during a moderate CO2 pneumoperitoneum in morbidly obese patients undergoing laparoscopic gastric bypass surgery.