Endotoxin removal is essential for the safety of biological products. To remove endotoxin efficiently, we used polymyxin B (PMB) affinity adsorbent to remove endotoxin from protein solutions by static adsorption. We studied the effects of spacer length and ligand density of the affinity adsorbent, pH, salt type and concentration, protein type and concentration, endotoxin concentration, and additive on endotoxin removal and protein recovery. Endotoxin content and protein concentration were determined by test and Lowry assay respectively. The results showed that PMB affinity adsorbent had high capacity, high adsorption speed, high removal efficiency and good reusability. In addition, ligand density, pH, salt concentration and the isoelectric point and hydrophobicity of protein all had remarkable influence on the endotoxin removal. Under the optimal conditions, the recoveries of hemoglobin, human serum albumin and lysozyme were 87.2%, 73.4% and 97.3%, respectively, and the corresponding endotoxin removal rates 99.8%, 97.9% and 99.7%, respectively. This study illustrated the effects of solution conditions on the efficiency of endotoxin removal and protein recovery, and would provide useful reference for the efficient removal of endotoxin from biological products.
Adsorption ; Chromatography, Affinity ; methods ; Drug Contamination ; prevention & control ; Endotoxins ; isolation & purification ; Hemoglobins ; isolation & purification ; Polymyxin B ; chemistry ; Proteins ; isolation & purification ; Pyrogens ; isolation & purification ; Serum Albumin ; isolation & purification ; Solutions

Objective:To investigate the current situation and influencing factors of patients′ satisfaction with nursing humanistic care, and to provide reference for improving the quality of such care provided by hospitals.Methods:From July to August 2022, outpatients and inpatients in 30 provinces were selected by multi-stage stratified sampling as the survey objects. A cross-sectional survey was conducted on an online platform, using the general information questionnaire and Chinese version of methodist health care system nurse caring instrument revised by the research group. The latter instrument consists of 12 dimensions. namely care coordination, competence, teaching/learning, emotional support, respect for individuality, physical comfort, availability, helping/trusting relationship, patient/family engagement, physical environment, spiritual environment and outcomes. Descriptive analysis was performed on the data collected by the questionnaires, and independent sample t-test and one-way ANOVA were used to analyze the influencing factors of patient satisfaction. Results:A total of 107 hospitals were selected for questionnaire survey, including 86 tertiary hospitals and 21 secondary hospitals, and 29 108 valid questionnaires were recovered. The patient satisfaction with nursing humanistic care scored (5.40±0.86); the top three dimensions were competence (5.50±0.89), emotional support (5.47±0.88) and helping/trusting relationship (5.46±0.86); the lowest scoring dimensions were teaching/learning (5.38±1.01), spiritual environment (5.36±1.04) and patient/family engagement (5.11±1.28). Differences with gender, age, marital status, child status, educational level, occupation, place of residence, economic region, per capita monthly income of the family, type of medical insurance, medical department visited and surgery or not presented significant differences on the patient satisfaction with nursing humanistic care scores ( P<0.05). Conclusions:The satisfaction of patients with hospital′s nursing humanistic care in China was at the middle to upper level. In the future, health education for patients should be strengthened, and a mode of family-engaged nursing humanistic care should be constructed in line with the Chinese cultural background. In the process of nursing services, the particularity of patient groups should be considered to better meet their needs.