High-throughput screening

high-throughput screening

High-throughput screening (HTS) involves the screening of compound libraries at a single concentration using biochemical or cell-based assays that are directed against a drug target or a desired phenotypic outcome, followed by confirmatory secondary dose response assays.

Automated dispensing reduces the tedium and repetitiveness and potential for error inherent in manual pipetting. This allows the setup and study of large numbers of microplates or microtubes for large-scale screening studies.

find out how we can:





High throughput screens (HTS) routinely require low volume dispensing technologies to reduce assay costs by minimising reagent and sample usage for a wide range of applications within academia and the drug discovery industry.

dragonfly discovery offers positive-displacement, non-contact, liquid handling and eliminates issues with clogging while providing reliable, accurate dispensing, agnostic of liquid class; reducing assay development time and improving robustness in screening.

  • rapid and reliable low volume (200 nL upwards) dispensing from a positive displacement disposable pipette (with 4 mL capacity)
  • 96, 384 & 1,536 well compatibility
  • integration friendly with optional auto-feed reservoirs
  • new software capability and UI to aid the design and development of complex assays, specifically in high density plate formats


A pre-requisite for efficient screening is rapid, automated selection of hits for confirmation and secondary profiling.

mosquito HTS offers an accurate and easy-to-use-solution to miniaturising any assay within an automated, high-throughput setting. Volume range is 25 nL–1.2 μL, which can be expanded to cover 25 nL–5 μL in conjunction with mosquito HV. By using mosquito’s unique positive displacement pipetting technology, dead volumes are minimised to under 0.3 μL.

Application areas include:

  • serial dilutions
  • plate reformatting and replication
  • acoustic plate source creation
  • next generation sequencing
  • genotyping
  • high-throughput MALDI-TOF MS


mirrorball no-wash multiplex immunoassays for biological discovery
With over 40% of therapeutic drugs targets currently being membrane-associated proteins, the study of monoclonal antibodies for both immunodiagnostic biomarkers and therapies is a large growth area in the pharmaceutical industry.

Key applications include:

  • biologics screening:
    hybridoma, phage display, B-cell cloning, antibody fragments, peptides, scFv, Fab
  • binding characterisation:
    Ki determination
  • functional assays:
    ell cycle, cell signalling & proliferation
  • quantification of soluble proteins:
    cytokines, hormones, growth factors


acumen Cellista is unique in providing the value of a medium content approach to multiplexed cell-based assay screening in a format that is manageable and approachable for high throughput screening (HTS).

  • don’t compromise speed for content: acumen Cellista brings biological relevance to your required throughput levels, enabling full library screening to ensure you never miss that potential blockbuster without the infrastructure requirements of high content solutions
  • immediate decision-making data: acumen Cellista’s cytometric approach delivers instant results and small file sizes so you don’t have to spend valuable time validating data, or managing a data mountain
  • be productive straight away: acumen Cellista is simple to operate without the need for specialist users or endless ongoing training


TTP Labtech’s comPOUND sample storage system gives you the ability to:

  • select any library subset quickly to meet the needs of your screening department
  • reduce potential damage to library stocks by only cherry-picking the samples you need
  • ensure sample integrity with temperature controlled, dry, inert, hermetically sealed environment
  • ensure throughput grows with your library by processing samples in parallel
  • easily expand your sample storage capability. Additional modules can be integrated in response to growing library size


arktic automated storage of cell, RNA, siRNA, DNA, native proteins (-80°C)

arktic is a low cost, compact storage unit which provides unrivalled storage density, full sample tracking and rapid retrieval.
To ensure viability and reduce sample degradation it is vital to minimise the risks of thawing, either within the cold zone or during sample selection.
arktic provides:

  • easy sample access and stable temperatures to give you unrivalled robustness and reliability for your -80°C storage requirements

high-throughput screening applications:

Compound Screening

Compound screening is an essential part of the early stage of the drug discovery process, to identify molecules that have activity on specific drug targets. Compounds identified as “hits” are further optimised using traditional medicinal chemistry (combinatorial chemistry) to determine chemical groups responsible for evoking a target biological effect or structure-activity-relationships (SAR). With such large numbers of compounds and chemical entities in compound libraries, the removal and handling of large numbers of samples from stores for assay set up can be a complex and time consuming process.

TTP Labtech’s self-contained biobanking modules, comPOUND and arktic, can be placed in remote locations to maximise valuable laboratory space. Using TTP Labtech’s pneumatic transport technology, sample tubes can be rapidly selected and transported to any laboratory without the need for manual intervention, thus improving the research workflow.

Aliquot transfer from stock plates or vials, serial dilution and plate preparation and replication require accurate but repetitive and time consuming pipetting, as well as meticulous sample labelling, tracking and management. As such, the ability to automate sample dispensing and processing is invaluable, providing reproducible and accurate volumes and significantly decreasing the turn-around time from compound synthesis to assay ready plate production.

TTP Labtech’s mosquito range of liquid handlers allow rapid, accurate, reproducible nanolitre volume compound dispensing for high speed plate set-up, irrespective of viscosity or environmental conditions.

Pharma and biotech companies today perceive they have to compromise between the convenience of target-based screening and the relevance of phenotypic screening. TTP Labtech’s acumen Cellista laser scanning imaging cytometer (LSIC) overcomes the challenges associated with full compound library phenotypic screening, allowing users the flexibility to choose the most appropriate strategy.

acumen Cellista is unique in providing the value of a high content approach in a format that is both manageable and approachable for high throughput screening (HTS).

Phenotypic Screening

The realisation that more first-in-class drugs have been discovered by phenotypic screening than by target-based screening has led the industry to revise the strategy for identifying new drug candidates. The emergence of novel technologies and advances in cell imaging has made it possible to re-consider phenotypic screening as a serious contender for drug development. Whilst the advantages of this approach are clear, implementation within a HTS setting can be complex as discussed in this white paper. With plate read times as low as 2 and a half minutes per plate regardless of plate format acumen Cellista offers a manageable solution for medium content HTS screens to bring improved physiological relevance over plate reader assays without the burden of a or throughput limitations of a microscope-based high content approach.

Our e-book, put together in collaboration with Genetic Engineering and Biotechnology News is devoted to phenotypic screening. It discusses the use of 3D cell cultures as a more physiologically relevant screening model for evaluating new drug candidates. They more closely resemble the structure, activity and extracellular environment of tissues in-vivo and therefore are more likely to be predictive of how cells will react in-vivo. Our interactive learning tool is available to download anywhere at any time and additional information can be found in the interactive bonus videos and a recent poster of a high throughput screening method to analyse the growth of tumour spheroids and colonies.

Find out more about phenotypic screening with acumen Cellista or, read our e-book here

Biologics Screening

Immunoassays have been, and are still, an essential tool during many stages of the drug discovery process, but these assays can become a bottleneck due to limited throughput and capability. ELISAs are simple and inexpensive but can only detect one target thereby numerous individual assays are required to measure multiple targets. Newer approaches address some of these limitations through multiplexing or homogeneous assay formats; however, these often result in greatly increased reagent and consumable costs. Many are limited in flexibility to just immunoassays, whereas more versatile systems such as flow cytometry are generally less suited to a screening environment. Find out more about how the mirrorball fluorescence cytometer is able to help remove some of these bottlenecks here.

Genomics Screening

RNA interference (RNAi) is a biological process in which RNA molecules inhibit gene expression. Two types of small ribonucleic acid (RNA) molecules, microRNA (miRNA) and small interfering RNA (siRNA) are central to RNA interference. RNAi has become a valuable research tool, both in cell culture and in living organisms, because synthetic dsRNA introduced into cells can selectively induce suppression of specific genes of interest.

By identifying gene products whose knockdown is associated with phenotypic changes, large-scale RNA-mediated interference screens have demonstrated previously unknown components of biological pathways.

The acumen Cellista laser-scanning imaging cytometer is ideal for screening RNAi studies both in cell culture, e.g. cell cycle analysis and toxicity testing, and in whole organisms such as C. elegans or drosophila. acumen Cellista combines whole well scanning with the ability to measure object number as part of the same assay, which gives researchers the capacity to normalise responses. This capability provides an inbuilt indication of cell proliferation,  cell toxicity, or can be used to quality control effects such as patchy cell growth within the well which can be missed when only capturing data from limited fields of view.

acumen Cellista’s high-throughput capability and rapid ‘on the fly’ analysis means it can conduct genome-wide screens in a matter of hours rather than weeks.

Toxicology Screening

Cell health (cytotoxicity) assays play a key role in the early drug discovery process as they study the effect of chemical substances and lead compounds on cells. The early identification of off-target drug effects results in more timely elimination of unsuitable lead compounds, which serves to reduce drug development costs. Not only do cell health assays provide a crucial means of ranking novel compounds during screening but they are also routinely employed to gain a better understanding of changes at the cellular level in disease pathologies.

Cytotoxicity assays commonly employ a multi-parametric approach enabling the capture of both phenotypic and mechanistic information. High content screening of the effect of lead compounds on multiple key cellular parameters such as plasma membrane integrity, DNA damage or synthesis, mitotic arrest, apoptosis, cell growth or motility is achievable through the use of high-throughput in-vitro cell-based assays.

TTP Labtech’s acumen Cellista high content imager is an ideal instrument for performing a wide range of multiplexed cytotoxicity assays. acumen’s laser scanning approach enables scanning of entire wells, cell by cell.

These assays include:

  • live/dead – using standard dyes such as calcein-AM/PI or TOTO-3/TMRMThese combinations provide a more cost-effective approach to bulk read assays, such as CellTitre–Glo®, and offer the benefit of multiplexing with additional phenotypic assays to gain more high content data
  • apoptosis – annexin V, Caspase-3, nuclear condensation
  • genotox – phophohistone H3

With plate read and analysis times as low as 2 ½ minutes, regardless of plate format, acumen Cellista can be used for primary screening in the determination of off-target drug effects in the earliest phases of drug discovery. Fast scan times and easy to use Cellista software mean it is ideal for multi-user environments such as core screening laboratories.

other cell biology applications

Major areas of cell biology research for the elucidation of disease mechanisms and drug discovery are study of cell structure and function, such as cell surface receptors, cell metabolism and homeostasis, and intra-cellular pathways and communication.

It is generally recognized that the study of cellular systems provides superior quality data to biochemical assays. The ability to study the molecular effects of a compound in a specific and relevant cellular context is of great advantage in the drug discovery process.

Cell-based assays have been successfully adapted to the high content screening (HCS) environment of today’s drug discovery industry, using a range of cell reagents (recombinant cells, antibodies, fluorescent probes, siRNA etc) and automated cell-based assay platforms, which employ a range of detection modes such as fluorescence, electrophysiological or imaging readouts.

TTP Labtech’s instrumentation can help automate and take the tedium out of routine plate set-up, assay development and screening in the cell biology application areas. We’re here to help, why not arrange a time to personally review your discovery processes with one of our specialists?