# Top 3 compact HPLC autosamplers in 2026 (and how to choose one)

> Three compact HPLC autosamplers you can buy in 2026, compared on verified size, vials, pressure and control, plus a checklist for choosing one.

Source: https://elutrolab.com/en/blog/compact-hplc-autosamplers
Published: 2026-10-13
Publisher: Elutrolab (https://elutrolab.com)

From the manufacturer datasheets we checked in October 2026, the three compact HPLC autosamplers worth a shortlist are the **SIELC Alltesta Mini** (160 × 145 × 195 mm, 3 kg, 48 vials), the **Axcend AutoFocus** (22.8 × 30.5 × 23.5 cm, 40 vials, made for the Axcend Focus LC) and the **HTA HT1500L** (355 × 380 × 520 mm, 8 kg, 45 vials, sold as compatible with any HPLC). The Alltesta Mini is the smallest and the most open to scripting, the AutoFocus completes a miniature capillary LC, and the HT1500L is a light, simple sampler for an existing HPLC. None of the three publishes a price.

## Key points

- "Compact" here means clearly smaller than a full-size sampler module such as Knauer's AZURA AS 6.1L (377 mm wide, 575 mm deep, 32 kg).
- Of the three, only the Alltesta Mini is a true miniature standalone sampler. Axcend presents the AutoFocus only as a companion to its Focus LC, and the HT1500L is narrow and light rather than small.
- Check pressure rating, injection principle, start signal and software support before size. A small sampler that cannot start your detector run adds work every day.
- Only the AutoFocus lists sample cooling (optional, 8 °C at 24 °C ambient).
- The Elutrolab AS-48, made by the company that publishes this blog, is close in size to the Alltesta Mini but is a prototype, so it is not ranked here.

## How we picked the three

We used four rules and applied them to manufacturer pages and datasheets only:

1. **You can order it new today.** The product page was live in October 2026.
2. **It injects into an LC flow path.** It takes sample from vials and loads it through an injection valve into a pressurised HPLC stream.
3. **The maker publishes outer dimensions, vial capacity and the control interface.** Where any other value is missing from the datasheet, the table says "not published".
4. **It is clearly smaller than a full-size module.** Our reference is the [Knauer AZURA AS 6.1L](https://www3.knauer.net/en/product/autosampler_as_61l-1/) in its preparative, cooled version: 377 × 300 × 575 mm (width × height × depth) and 32 kg.

Within those rules we ranked by footprint and weight, then pressure rating, injection range and control options.

### What we looked at and left out

- **Shimadzu i-Series (LC-2070, LC-2080).** An integrated LC with pump, sampler, oven and detector in one housing of [410 × 500 × 605 mm (W × D × H) and 58-63 kg](https://www.shimadzu.com/an/products/liquid-chromatography/hplcuhplc/i-series/spec.html). Compact for a complete HPLC, but the sampler is built into the housing.
- **Axcend Focus LC.** A complete capillary LC of [22.8 × 35.5 × 20.8 cm and 8.0 kg](https://axcendcorp.com/hubfs/AXCEND%20%28Pre-Transition%29/Rebranded%20Collateral/Axcend%20Focus%20LC%20Specs.pdf), with a pump rated to 689 bar (10,000 psi). Its matching sampler is pick 2 below.
- **Gilson GX-241.** A flexible XYZ liquid handler. Gilson's installation document for the GX-241 ASPEC (solid-phase extraction) configuration lists [39 × 50 × 51.5 cm (W × D × H)](https://digitalassets.avantorsciences.com/adaptivemedia/rendition/id_c127a3553c6974447a81b9956764c042f6a132cb/vid_6631352a3571bc48f0ae7490639ee456e3fa30e7/prid_original/clid_SAPDAM), the size of a full module.
- **Spark Holland Alias and Nexas.** Full-featured samplers rated up to 18,000 psi for the [Alias UHPLC version](https://www.sparkholland.com/wp-content/uploads/2023/03/Productbrochure_Spark_ALIAS.pdf) and 20,000 psi for the [Nexas UHPLC version](https://www.sparkholland.com/wp-content/uploads/2025/09/Productbrochure_Spark_NEXAS_V3.pdf). Spark describes itself as a full-service OEM partner, and the brochures give no outer dimensions.
- **VICI Valco.** VICI's catalogue lists injectors, selector valves and actuators, not a vial autosampler. Its multiposition valves can act as a stream selector under DataApex Clarity with the [AS Control module](https://www.dataapex.com/product/controls-as-multiposition-valve).
- **Teledyne.** We found no current manufacturer datasheet for a Teledyne LC vial autosampler, only resale listings.

## Compact HPLC autosamplers compared

Values are as published; the dimension order is copied from each datasheet, because SIELC and HTA do not use W × D × H.

| Specification | SIELC Alltesta Mini | Axcend AutoFocus | HTA HT1500L |
|---|---|---|---|
| Type | Standalone mini sampler | Sampler module for the Axcend Focus LC | Standalone benchtop sampler |
| Published size | 160 × 145 × 195 mm (labelled W × H × L) | 22.8 × 30.5 × 23.5 cm (W × D × H) | 355 × 380 × 520 mm (W × H × D) |
| Weight | 3 kg | 6.6 kg | 8 kg |
| Sample capacity | 48 vials; 54 vials, 96- or 384-well plate as custom options | 40 × 2 mL vials or 96-well plates | 45 × 4 mL vials (HT1501L) or 25 × 40 mL vials (HT1502L) |
| Pressure rating | Up to 5000 psi (345 bar) | Not published for the sampler; Focus LC pump 689 bar | Not published |
| Injection valve | 6-port, 2-position; 7 × 6 and 10 × 9 options | Loads the Focus LC injection valve | 6-port, 2-position |
| Injection range | Not published | 0.1-50 µL (more with multiplex loading) | Full loop only; volume set by the loop |
| Accuracy or precision | Volume accuracy 0.1 µL | Precision < 0.25% | RSD ≤ 0.25% |
| Carryover | Not published | < 0.02% | ≤ 0.01% (excluding transfer line) |
| Cycle time | Not published | < 30 s | ≤ 60 s |
| Sample cooling | Not listed | Optional, 8 °C at 24 °C ambient | Not listed |
| Power | 24 V | 100-240 V AC | 100-240 V AC, 60 W |
| Control | RS-232 virtual COM port over USB; serial protocol on request | USB; Axcend software, Agilent OpenLab, DataApex Clarity | Keypad, USB and TTL; HTA Autosampler Manager |
| Public price | Not published (varies by configuration) | Not published | Not published |

Sources (seen October 2026): [SIELC product page](https://sielc.com/product/alltesta-autosampler), [specification sheet](https://sielc.com/wp-content/uploads/2025/03/Alltesta%E2%84%A2-Mini-Autosampler-Technical-Specifications.pdf), [Axcend AutoFocus specifications](https://axcendcorp.com/hubfs/AXCEND%20%28Pre-Transition%29/Rebranded%20Collateral/Axcend%20AutoFocus%20Specs.pdf), [HTA HT1500L flyer](https://d2f9yq8vfu6hob.cloudfront.net/uploads/Flyer_HT1500L%20leaflet_EN.pdf).

## The three picks in detail

### 1. SIELC Alltesta Mini: smallest footprint and open serial control

SIELC lists the Alltesta Mini at 160 × 145 × 195 mm under the label "WHL". Read literally (width, height, length), it is 160 mm wide, 145 mm high and 195 mm deep, so confirm with SIELC if a few millimetres matter. It weighs 3 kg and runs on 24 V.

The standard build has a 6-port, 2-position valve rated up to 5000 psi (345 bar), a 4000 µL low-pressure syringe, a 36 mm needle and a wash station. The customisable build adds a 120 µL high-pressure syringe, 7 × 6 and 10 × 9 valves and plate formats. Control is through a USB virtual COM port with a serial command set; SIELC supplies the protocol on request and a Windows demo program. The same sampler is the front end of SIELC's [Alltesta Isocratic Automated Analyzer](https://sielc.com/product/alltesta-isocratic-automated-analyzer), which is rated up to 3000 psi (206 bar) with 1-75 µL injections.

**Best for:** portable or OEM analysers, fume hoods, glove boxes and labs that script their instruments. **Check first:** no injection range, carryover or cooling is published, and no data system driver is listed, so plan how your software will start each run.

### 2. Axcend AutoFocus: a miniature LC with its own autosampler

Axcend does not sell the AutoFocus as a general-purpose sampler. It sits on top of the Axcend Focus LC and delivers sample straight to that system's injection valve, which Axcend says minimises extra-column volume. As a pair, the whole LC with autosampler stands on the Focus LC footprint of 22.8 × 35.5 cm, smaller than an A3 sheet (297 × 420 mm).

Axcend publishes a complete datasheet: 40 × 2 mL vials or 96-well plates, 0.1-50 µL, a cycle under 30 s, precision under 0.25%, carryover under 0.02%, optional cooling to 8 °C at 24 °C ambient, and control from Axcend's software, Agilent OpenLab or DataApex Clarity.

**Best for:** labs that want a full LC in a fume hood, on a crowded bench or at line, and are happy with capillary columns (the pump delivers 0.4-10 µL/min). **Check first:** Axcend presents it only as a Focus LC accessory and says nothing about other LCs, so ask before planning to use it with another HPLC.

### 3. HTA HT1500L: a light universal sampler for an existing HPLC

HTA calls the HT1500L a "no frills" HPLC autosampler. It is a standalone unit sold as compatible with any HPLC system, with a keypad to start runs, USB and TTL connections, 45 × 4 mL vials in five removable racks, full-loop injection, a cycle of 60 s or less, RSD of 0.25% or better and carryover of 0.01% or less. HTA's free Autosampler Manager software sets up methods; a 21 CFR Part 11 version is sold separately.

At 355 mm wide and 8 kg it is narrower and far lighter than a full-size module, but its 520 mm depth needs a normal bench. **Best for:** adding automation to a manual-injection HPLC. **Check first:** HTA does not publish a pressure rating, and full-loop injection uses more sample than the loop volume (a common rule of thumb is 2-3 loop volumes).

## How to choose a compact HPLC autosampler

### How much bench space will it really take?

Compare footprint areas, then add room behind for tubing and cables (allow 50-100 mm as a rule of thumb).

```text
Footprint = width × depth
Alltesta Mini   0.160 m × 0.195 m = 0.031 m²   (reading the label literally)
AutoFocus       stacks on the Focus LC, adds no footprint
HT1500L         0.355 m × 0.520 m = 0.185 m²
AZURA AS 6.1L   0.377 m × 0.575 m = 0.217 m²
```

The Alltesta Mini needs about one seventh of the bench area of the full-size Knauer module. Our guide to [HPLC bench space](/en/blog/hplc-bench-space) compares whole stacks.

### What pressure rating do you need?

The valve rating must exceed the highest pressure your method reaches (in a methanol and water gradient, usually near the most viscous mixture). Keep about 20% headroom as a rule of thumb. Conversions: 1 bar = 14.5 psi, 345 bar = 5000 psi, 689 bar = 10,000 psi.

Worked example: a method peaks at 280 bar. 280 × 1.2 = 336 bar, so a 345 bar (5000 psi) sampler is just enough; a 400 bar method is not. More in [HPLC pressure ratings in psi, bar and MPa](/en/blog/hplc-pressure-psi-bar).

### Which injection principle suits your samples?

Full-loop injection gives the best precision but wastes sample. Partial-loop and needle-in-flow designs waste less sample, but precision then depends on the metering syringe. See [how an HPLC autosampler works](/en/blog/how-an-hplc-autosampler-works) and [full-loop vs partial-loop injection](/en/blog/full-loop-vs-partial-loop-injection).

### Will your data system control it?

There are three routes: a driver in your chromatography data system (the AutoFocus lists OpenLab and Clarity), the maker's own software (HTA Autosampler Manager), or a documented serial protocol that you script yourself (Alltesta Mini). Scripting is flexible, but you validate and maintain the code.

### How does the detector know when the sample was injected?

If the data system does not drive the sampler, the sampler must send a start signal (contact closure or TTL) at the moment the valve switches; otherwise time zero is not tied to the injection and retention times lose precision. The HT1500L lists TTL. The Alltesta Mini datasheet lists only the serial port, so ask SIELC.

### Do you need sample cooling?

Count the queue time. Worked example: 48 vials at 12 minutes per run means the last vial waits more than 9 hours (47 × 12 min = 9.4 h). If your analyte is not stable that long at room temperature, you need cooling (only the AutoFocus offers it here) or shorter queues.

### Who services it, and what do the parts cost?

Ask for prices and lead times on rotor seals, syringe seals and needles, and whether service is by the maker, a local distributor or mail-in. Our [autosampler troubleshooting guide](/en/blog/autosampler-troubleshooting) lists the parts that wear first.

### What will it cost?

No price is published for any of the three; SIELC says the price varies by configuration. Request quotes for the same configuration (vials, valve, software, warranty) and compare them with a [used or refurbished full-size autosampler](/en/blog/used-hplc-autosampler-buying-guide) if bench space is not your main constraint.

## In development: the Elutrolab AS-48

Elutrolab, the company that publishes this blog, makes the AS-48. It is an engineering prototype: not shipping, available for quotation only, with early units possibly going to pilot users. Values marked * are design targets to be confirmed by testing before series production. It is not one of the three above because you cannot buy a production unit today.

It is close in size to the Alltesta Mini and shares several design choices with it:

- 140 × 155 × 168 mm (W × D × H), 174 mm high including feet, about 3.2 kg*, 24 V DC. That is a footprint of 0.140 m × 0.155 m = 0.022 m², about a tenth of the AZURA AS 6.1L reference module (0.217 m²)
- 48 × 2 mL vials (12 × 32 mm) on a removable rack with an SBS footprint
- 6-port, 2-position valve with a 5000 psi (345 bar) design rating*, with an angle sensor that checks every switch
- Fixed loop with backflush to the column and a low-pressure needle; 1-100 µL with the standard 240 µL loop, 1-5 µL with an optional 25 µL loop
- Volume accuracy ±0.1 µL after solvent-specific calibration*, cycle time from 30 s*
- USB-C virtual COM port with a documented plain-text command set

What it does not offer: no drivers for Empower, Chromeleon, OpenLab or other data systems, no sample cooling, and no inject-start or contact-closure output in the current specification (whether one is added is not decided). Full details are on the [AS-48 specifications](/en#specifications).

> Note from Elutrolab: The Elutrolab AS-48 is a 140 × 155 × 168 mm autosampler with 48 vials, a 6-port valve rated to 5000 psi* and plain-text serial control over USB. It is an engineering prototype; values marked * are design targets.


## Frequently asked questions

### What is the smallest HPLC autosampler you can buy?

Of the samplers with published dimensions that we checked in October 2026, the SIELC Alltesta Mini is the smallest: 160 × 145 × 195 mm (published as W × H × L) and 3 kg, with 48 vials and a rating of up to 5000 psi (345 bar).

### Can a compact autosampler be used with any HPLC system?

A standalone unit can be plumbed into any flow path whose pressure is within its valve rating, but you also need a way to start each run, either a driver in your data system or a start signal such as TTL. HTA sells the HT1500L as compatible with any HPLC; Axcend describes the AutoFocus only as a companion to its own Focus LC.

### Do compact autosamplers handle UHPLC pressure?

Not as far as published data shows. The Alltesta Mini is rated up to 5000 psi (345 bar), which covers conventional HPLC. HTA does not publish a rating for the HT1500L. The Axcend Focus LC that the AutoFocus feeds has a pump rated to 689 bar (10,000 psi).

### Do compact autosamplers have sample cooling?

Of the three in this comparison, only the Axcend AutoFocus lists cooling, as an option that reaches 8 °C at 24 °C ambient. Neither the Alltesta Mini nor the HT1500L lists cooling in its specifications.

### Is the Elutrolab AS-48 available to buy?

Not yet. It is an engineering prototype made by Elutrolab, offered on request for quotation only, and values marked * in its specification are design targets still to be confirmed by testing.


## Sources

- [SIELC Technologies: Alltesta Mini Autosampler product page](https://sielc.com/product/alltesta-autosampler)
- [SIELC Technologies: Alltesta Mini Autosampler technical specifications (PDF)](https://sielc.com/wp-content/uploads/2025/03/Alltesta%E2%84%A2-Mini-Autosampler-Technical-Specifications.pdf)
- [SIELC Technologies: Alltesta Isocratic Automated Analyzer](https://sielc.com/product/alltesta-isocratic-automated-analyzer)
- [Axcend: AutoFocus autosampler specifications (PDF)](https://axcendcorp.com/hubfs/AXCEND%20%28Pre-Transition%29/Rebranded%20Collateral/Axcend%20AutoFocus%20Specs.pdf)
- [Axcend: AutoFocus product page](https://axcendcorp.com/autofocus)
- [Axcend: Focus LC specifications (PDF)](https://axcendcorp.com/hubfs/AXCEND%20%28Pre-Transition%29/Rebranded%20Collateral/Axcend%20Focus%20LC%20Specs.pdf)
- [HTA: HT1500L HPLC autosampler product page](https://www.hta-it.com/products/ht1500l.html)
- [HTA: HT1500L flyer with technical specifications (PDF)](https://d2f9yq8vfu6hob.cloudfront.net/uploads/Flyer_HT1500L%20leaflet_EN.pdf)
- [Knauer: AZURA Autosampler AS 6.1L, preparative version with cooling (AAA41AA)](https://www3.knauer.net/en/product/autosampler_as_61l-1/)
- [Shimadzu: i-Series integrated HPLC specifications](https://www.shimadzu.com/an/products/liquid-chromatography/hplcuhplc/i-series/spec.html)
- [Gilson: GX-241 ASPEC installation qualification procedures (LT319669-01)](https://digitalassets.avantorsciences.com/adaptivemedia/rendition/id_c127a3553c6974447a81b9956764c042f6a132cb/vid_6631352a3571bc48f0ae7490639ee456e3fa30e7/prid_original/clid_SAPDAM)
- [Spark Holland: Alias autosampler brochure (PDF)](https://www.sparkholland.com/wp-content/uploads/2023/03/Productbrochure_Spark_ALIAS.pdf)
- [Spark Holland: Nexas autosampler brochure (PDF)](https://www.sparkholland.com/wp-content/uploads/2025/09/Productbrochure_Spark_NEXAS_V3.pdf)
- [DataApex: Clarity control module for VICI Valco multiposition valves used as an autosampler](https://www.dataapex.com/product/controls-as-multiposition-valve)