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Various flow sample handling approaches coupled to capillary electrophoresis (CE) are reviewed, covering the research in this field in the 12 years since the milestone year of 1997, when practical interfaces to on-line couple flow injection (FI) and capillary electrophoresis were first developed independently by two research groups. Some previous attempts are also presented. Since 1997 a plethora of ingenious coupled systems have been developed. Although several reviews are available on various aspects of the topic, we have opted for a comprehensive overview of all FI-CE systems, as well as related and similar systems. This coupling has thus also led to the development of systems based on hybrids between the classical and microchip approaches. Truly microchip FI-CE systems are also included in this review. The developed systems have been used for various sample treatments, including on-line membrane-assisted sample treatment, column-based preconcentration, on-line derivatization and monitoring, to name just a few. The utility of coupling flow sampling to CE has been demonstrated in various practical applications that are discussed in detail. The current state-of-the-art and foreseeable future developments are also discussed.

BACKGROUND: Few studies have directly compared the renoprotective effects of angiotensin II-receptor blockers and angiotensin-converting-enzyme (ACE) inhibitors in persons with type 2 diabetes. METHODS: In this prospective, multicenter, double-blind, five-year study, we randomly assigned 250 subjects with type 2 diabetes and early nephropathy to receive either the angiotensin II-receptor blocker telmisartan (80 mg daily, in 120 subjects) or the ACE inhibitor enalapril (20 mg daily, in 130 subjects). The primary end point was the change in the glomerular filtration rate (determined by measuring the plasma clearance of iohexol) between the baseline value and the last available value during the five-year treatment period. Secondary end points included the annual changes in the glomerular filtration rate, serum creatinine level, urinary albumin excretion, and blood pressure, the rates of end-stage renal disease and cardiovascular events, and the rate of death from all causes. RESULTS: After five years, the change in the glomerular filtration rate was -17.9 ml per minute per 1.73 m2 of body-surface area, where the minus sign denotes a decrement, with telmisartan (in 103 subjects), as compared with -14.9 ml per minute per 1.73 m2 with enalapril (in 113 subjects), for a treatment difference of -3.0 ml per minute per 1.73 m2 (95 percent confidence interval, -7.6 to 1.6 ml per minute per 1.73 m2). The lower boundary of the confidence interval, in favor of enalapril, was greater than the pre-defined margin of -10.0 ml per minute per 1.73 m2, indicating that telmisartan was not inferior to enalapril. The effects of the two agents on the secondary end points were not significantly different after five years. CONCLUSIONS: Telmisartan is not inferior to enalapril in providing long-term renoprotection in persons with type 2 diabetes. These findings do not necessarily apply to persons with more advanced nephropathy, but they support the clinical equivalence of angiotensin II-recept

OBJECTIVES: To study the biological effects of nebulized insulin, administered intrapulmonary, to healthy volunteers. DESIGN: A double-blind, randomized, controlled intervention study. SETTING: The department of Internal Medicine, University Hospital, Linköping, Sweden. SUBJECTS: Eight healthy, non-smoking volunteers, with a mean age of 28 (range 22 to 56) years. INTERVENTIONS: Regular human insulin 100 U mL-1 (Actrapid) or 0.9% saline was given randomly as an oral inhalation. Insulin was given in three different doses (40, 80 and 160 U). Aerosol was generated by a new jet nebulizer. MAIN OUTCOME MEASURES: Blood glucose, serum insulin, and serum C-peptide. RESULTS: After the 160 U insulin dose the blood glucose concentration (mean +/- SE) fell from 4.3 +/- 0.2 to 2.8 +/- 0.2 mmol L-1 (P < 0.001), concomitant with an increase in mean serum insulin concentrations, rising from 9.5 +/- 1.5 to 26.1 +/- 2.5 mU L-1 (P < 0.001). Serum C-peptide concentrations simultaneously decreased from 0.48 +/- 0.03 to 0.12 +/- 0.02 mmol L-1 (P < 0.001). All changes were dose dependent. No adverse reactions were noted and no significant changes in lung function tests. CONCLUSIONS: Intrapulmonary insulin administration to healthy subjects can induce a significant hypoglycaemia and cause a clinically relevant increase in serum insulin concentrations. If similar results can be obtained when administering insulin to diabetic subjects, this insulin administration route can be a future complement to certain groups of patients.

We investigated the efficacy of intrapulmonary administration of short-acting porcine insulin in anaesthetized pigs (n = 14) in a randomized intervention study. Insulin was administered by a new jet nebulizer (Maxin) in a random order at different doses, 0 (saline), 10 or 40 U. The hypoglycaemic effect was compared to control (0.9% saline). Blood glucose and serum insulin concentrations were followed at specified time intervals for 90 min. Plasma catecholamine concentrations were measured in order to estimate the concurrent stress. Nebulized insulin caused a significant decrease in blood glucose concentrations (p < 0.0001) (n = 28) at all doses used. The decrease in mean blood glucose concentration from the start of nebulization was 39 +/- 3% (mean +/- SEM), falling from 4.6 +/- 0.1 to 2.8 +/- 0.2 mmol 1(-1), with a nadir at 40 min after the 40 U insulin dose (n = 10). Serum insulin concentration rose from (mean +/- SEM) 5.2 +/- 0.1 to 25 +/- 9 mU 1(-1) after the insulin dose of 40 U (n = 10), the peak value occurred at 30 min. The plasma catecholamine concentrations increased significantly (p < 0.0001) (n = 28) from 0 to 60 min, this increase was similar for control and for different insulin doses. We conclude that intrapulmonary administration of insulin can cause a significant decrease in blood glucose concentrations in anaesthetized and mechanically ventilated pigs and results in clinically relevant serum insulin levels. Similar effects in humans would make inhaled insulin possible for clinical use.

The effects of intrapulmonary insulin administration in non-insulin-dependent diabetes mellitus (NIDDM) were studied in 12 patients in a double-blind randomized placebo-controlled intervention study. Regular human insulin, 100 U ml-1, was given as an aerosol by oral inhalation after a 12-h fasting. A significant decrease in blood glucose concentration, from 10.2 +/- 0.5 to 6.1 +/- 0.5 mmol l-1 (p < 0.0001) and a significant rise in serum insulin concentration, from 11.2 +/- 1.8 to 28.0 +/- 2.6 mU ml-1 (p < 0.0001), was seen. Serum C-peptide levels decreased from 1.6 +/- 0.2 to 1.0 +/- 0.1 nmol l-1 (p < 0.0001). No side-effects were reported following aerosol inhalation. If similar results can be obtained when using this route for insulin administration to insulin-dependent diabetes mellitus patients, this may be a useful complement to traditional subcutaneous insulin injections in these patients.