Nano liquid chromatography uses columns with internal diameters between 20-100 μm and flow rates of nanoliters per minute, providing advantages over traditional HPLC including lower mobile phase and sample consumption, high separation efficiency even with small samples, and easy coupling to mass spectrometry. The document discusses how nano LC is well-suited for pharmaceutical analysis applications requiring detection of drugs and pharmaceuticals at nano or low levels.

1. New Developments in HPLC
Role of Nano liquid chromatography
in Pharmaceutical Analysis

2. Introduction
• The development of miniaturized systems is not a recent event. In the 1950s, the
use of capillary columns for gas chromatography was proposed by Golay and
Horváth.
• Recently, the great increase in miniaturized LC systems has been driven by
biological applications, primarily proteomics research.
• Traditional analyses by high-performance liquid chromatography (HPLC) are
performed using columns with i.d. of 3.5–4.6 mm. These analytical columns have
typical flow rates of 1.0 mL/min.
• Columns with smaller dimensions (internal diameters of 20–100 µm) that use flow
rates of nanoliters per minute are called nano columns and are used in nano-LC.

3. Nano liquid chromatography
• Karlsson and Novotny introduced the concept of NLC in 1988 and since then many
advancements have been reported in the literature.
• NLC may be defined as ‘a modality of chromatography involving samples in nano
gram concentration, mobile phase flow in nanoliter per minutes with detection at
nano gram or pico gram per milliliter.
• True and complete nano-chromatography is only possible on chip, which is also
called as Lab-on-Chip Chromatography.
Advantages :
(i) The large decrease in mobile and stationary phase consumption, including toxic
reagents
(ii) The small sample needed
(iii) The high efficiency separations while maintaining the same retention behavior
(iv) The easy coupling to mass spectrometry (MS).

5. • Pharmaceutical analysis is an integral part in pharmacokinetics and
pharmacodynamics studies, which needs accurate analyses of drugs. The
analytical techniques should be capable to detect drugs and pharmaceutical at
nano or low detection limits.