Biological sample pretreatment is an important step in biological sample analysis. Due to the diversity of biological matrices, the analysis of target substances in these samples presents significant challenges to sample processing. To meet these emerging demands on biopharmaceutical analysis, this paper summarizes several new techniques of on-line biological sample processing: solid phase extraction, solid phase micro-extraction, column switching, limited intake filler, molecularly imprinted solid phase extraction, tubular column, and micro-dialysis. We describe new developments, principles, and characteristics of these techniques, and the application of liquid chromatography-mass spectrometry (LC-MS) in biopharmaceutical analysis with these new techniques in on-line biological sample processing.

Zidovudine (AZT), the first drug approved by the US Food and Drug Administration for the treatment of human immunodeficiency virus (HIV) infection, is metabolized in the host cells to 5'-AZT triphosphate (AZT-TP) which inhibits HIV reverse transcriptase. As the pharmacokinetics of AZT and its phosphorylated metabolites in human peripheral blood mononuclear cells (hPBMCs) is limited, the aim of this study was to determine the pharmacokinetic parameters of AZT and its phosphorylated metabolites in hPBMCs from 12 healthy Chinese male subjects after a single oral dose of 600 mg of AZT. Blood samples were collected prior to drug administration, then at 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 5, 6, 8 and 10 h after drug administration. Mononuclear cells collected by Ficoll-Hypaque density gradient centrifugation were used for determination of AZT and metabolites [AZT monophosphate (AZT-MP), AZT diphosphate (AZT-DP) and AZT-TP] and the plasma was used to evaluate the pharmacokinetics of AZT. Plasma concentration of AZT peaked within 0.583 h and intracellular concentrations of AZT, AZT-MP, AZT-DP and AZT-TP peaked within 1.083, 1.500, 1.417 and 1.583 h, respectively. AZT in plasma was eliminated rapidly with t 1/2 of 2.022 h, and AZT-MP, AZT-DP and AZT-TP were eliminated with t 1/2 of 13.428, 8.285 and 4.240 h, respectively. The plasma concentration of the phosphorylated metabolites was not quantifiable.

Objective: To analyze the characteristics of trigeminal event-related potentials (tERPs) in different kinds of olfactory disorders (OD), and to evaluate the importance of tERPs for the patients with olfactory dysfunction. Methods: Clinical data of 314 patients with olfactory dysfunction from the Smell and Taste Clinics in Beijing Anzhen Hospital from 2015 to 2021 were retrospectively reviewed, including 158 males and 156 females, aging from 6 to 78 years. The control group consisted of healthy people from medical examination center, who were gender and age matched. The clinical characteristics of OD were analyzed using Sniffin' Sticks test, olfactory event-related potentials (oERPs), tERPs and acoustic rhinometry test. SPSS 17.0 software was used to compare the difference of tERPs between the two groups, and to analyze the related factors affecting trigeminal function. Results: The ratio of tERPs presence was different in OD caused by different reasons: head traumatic OD (54.9%), post-virus infection OD (63.6%), sinonasal inflammatory OD (68.4%) and OD due to other causes (56.9%). Compared with controls, tERPs signals in OD patients showed a significant lower amplitude in the N₁ wave (all P<0.001), and lower amplitude in the P₂ wave in most OD patients (head trauma t=-4.11, P<0.001; sinonasal inflammation t=-2.04, P=0.046; others t=-2.40, P=0.020) except in OD by post-virus infection (t=-1.98, P=0.052). tERPs signals in OD patients by sinonasal inflammation showed longer latency in the N₁ wave (t=2.15, P=0.036), but this difference was not observed in other OD patients (all P>0.05). tERPs signals were significantly correlated with the Sniffin' Sticks score, deficiency of oERPs and nasal minimum cross-sectional area (all P<0.05). Conclusions: OD patients show neurophysiologic deficits in trigeminal function. The absence of tERPs or lower amplitude in N₁ waves are the important characteristics of patients with OD.
Evoked Potentials/physiology* ; Female ; Humans ; Inflammation ; Male ; Olfaction Disorders/etiology* ; Retrospective Studies ; Smell/physiology* ; Virus Diseases/complications*