Everything That’s Old is New Again

Introducing HALO-5A Truly “High Performance”

5µ Particle

How Much Does a Theoretical Plate Weigh?

Introduction

HALO core-shell particles are unique high-purity silica particles for stable high efficiency packed columns that are capable of very fast separations with modest back pressures

Original HALO particles are 2.7-microns with 90 Å pores HALO provides the efficiency of sub-2-micron particles at

half the pressure New HALO-5 particles are ~ 5-microns with 90 Å pores HALO-5 provides the efficiency of 3-micron particles with

the pressure of 5-micron particles

0.6 µm

~ 5 µm

SEM of ~ 5 µm HALO Fused-core Graphical representation of ~ 5 µm HALO Fused-core

HALO® -5 Fused-Core Particles

• As predicted by theory, the smaller the particle, the smaller the plate height (e.g., the sharper the peaks)• The 4 µm and 2.2 µm particles are from R&D batches

• The reduced plate height, h (same plate height data divided by the particle size), provides a measure of packed bed quality.

• The larger-particle HALO packings exhibit lower values for h, indicating more homogeneous packed beds. HALO(2.7) h = 1.5, HALO-5 h = 1.2!

• When operated at optimum flow rates, HALO-5 columns provide the highest number of theoretical plates per unit of pressure

More Theoretical Plates at Lower Pressure

So how much does a theoretical plate weigh?

Based on the previous graph, a theoretical plate from a column packed with 1.8µ particles weighs 0.025 bar. A theoretical plate from a column packed with HALO-5 weighs 0.0028 bar.

Practical significance: You get 10X as many HALO-5 plates per pound!

HALO-5 Bonded Phases

C18 (octadecyl)

PFP(pentafluorophenylpropyl)

Available November 2012

- Phenyl-Hexyl

- C8

- ES-CN

Available February 2013

- HILIC

-Penta-HILIC

Who Should Use HALO-5 Columns?

Users who currently use 3- or 5-micron particle columns and want to increase their efficiency and speed

Anyone wanting to transfer a method to a routine laboratory

Users who want more speed or who want more separation power but are owners of pressure-limited HPLC instruments (400 bar max pressure)

ConclusionsRegarding HALO-5 Columns

Produce unusual column efficiency; reduced plate heights h of ~1.2 for small molecules making them the first high-performance 5-micron columns in the world.

Efficiency and separation speed rivals that of 3-μm columns, but with about one-half the pressure.

Thin porous outer shell results in superior mass transfer kinetics and better efficiency at high mobile phase velocities, especially for larger molecules.

2-μm porosity frits allow the convenience and ruggedness of columns with 5 μm particles.

Strong particles allow pressures of at least 600 bar.

The line it is drawn, the curse it is castThe slow one now will later be fastAs the present now will later be pastThe order is rapidly fadin’And the first one now will later be lastFor the times they are a-changin’

Bob Dylan 1964

• HALO-5 Columns Can be Substituted for 5-Micron Totally Porous Columns to Provide Sharper Peaks and Shorter Analysis

Times Under Identical Method Parameters

Easy Transfer from Existing Methods

• HALO-5 Columns Provide the Same Efficiency as 3-Micron Columns at about Half the Pressure

Obtain 5-Micron Benefits for 3-Micron Methods

PEAK IDENTITIES (in order):1. Uracil2. Resorcinol3. Aniline4. 4-Chloroaniline5. Acetoacetanilide6. Dimethylphthalate7. Cinnamyl alcohol8. 2,6-Dinitrotoluene9. Tolbutamide10. 4-Chloro-3-nitroanisole

• Methods are easily transferred from HALO 2.7-micron columns to HALO-5 Columns with only minor adjustment

to mobile phase strength

Comparable Selectivity with 2.7-Micron HALO

5000

10000

15000

20000

25000

30000

35000

0.01 0.1 1 10 100

Plat

e N

umbe

r

µg of 1-Cl-4-Nitrobenzene

2.7 µm Fused-Core, 0.5 µm shell

5 µm Fused-Core, 0.6 µm shell

5 µm Totally porous

HALO-5 Columns Exhibit the Same Sample Loadability as 2.7-Micron HALO Columns and are Similar to 5-Micron Totally Porous Columns

Back Pressure Plots for Columns of Different Particle Sizes

Mobile Phase Flow Rate, mL/min

0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0

Pre

ssu

re,

ba

r

0

100

200

300

400

500

600

2.7 m Halo fused-core3 m totally porous4 m Halo fused-core5 m Halo fused-core5 m totally porousLinear regression

•Columns: 150 x 4.6 mm, C18•Mobile Phase:

50% ACN, 50% Water•Temperature: 30°C•Instruments: Agilent 1100 or Agilent 1200 SL